AR 5 ATTACHMENT A — Pasadena City Council, July 8, 2024 (part 1 of 2)

Attachment A - Initial Study and Mitigated Negative Declaration, Mitigation Monitoring and Reporting Program,
Public Comment Letters and Corresponding City Responses fMSMW^iiiSKS
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Final Initial Study andMitigated Negative Declaration
Explorer Well Project
Prepared forPrepared by
City of Pasadena
Water and Power Department
150 South Los Rabies Avenue, #200
Pasadena, California 91101
Psomas
225 South Lake Avenue, Suite 1000
Pasadena, California 91101
April 2024
Explorer Well Project
Final IS/MND

TABLE OF CONTENTS
Section Page
Section 1.0 Responses to Comments on the Initial Study/Mitigated Negative Declaration for the Explorer Well Project........................................................ 1 Section 2.0 Errata (Clarifications and Revisions)................................................................ 10

APPENDICES
AppendixA- Draft Initial Study/Mitigated Negative Declaration B - Mitigation Monitoring and Report Program (MMRP)
Table of Contents
Explorer Well Project
Final IS/MND
SECTION 1.0

RESPONSES TO COMMENTS ON THE

INITIAL STUDY/MITIGATED NEGATIVE DECLARATION FOR THE

EXPLORER WELL PROJECT
Pursuant to the California Environmental Quality Act (CEQA), the potential environmental effects of the proposed Explorer Well Project (Project) have been analyzed in an Initial Study/MitigatedNegative Declaration (IS/MND), dated February 2024, which is provided as Appendix A. The Draft IS/MND was subject to a 30-day public review period, which began on February 5, 2024, and ended on March 4, 2024. The City distributed a Notice of Intent (N01) to adopt an MND along with the IS.

During the public review period, three emails from two individuals were received including:

Two emails from Lori Schmitz, a staff member with the State Water Resources Control Board; and
One email from Darren Dowell, a resident.

The comments are provided below along with the City's responses to comments.The State CEQA Guidelines Section 15074(b) states that prior to approving a project, the leadagency must consider the IS/MND together with any comments received during the public review process. Written responses to comments on an IS/MND are not required by CEQA; however, the City of Pasadena, as lead agency, has prepared written responses to the comments received.The comment email, followed by the City's responses, are attached. The number provided in the right margin of the comment letters corresponds to the response to the comment.Based on the evaluation in the IS/MND, the City has determined that all potential impacts associated with the Project are less than significant with incorporation of identified mitigationmeasures. A Mitigation Monitoring and Reporting Program (MMRP) has been prepared for the Project, which will be used to track and implement these mitigation measures. The MMRP is provided as Appendix B of this Final IS/MNDIn conclusion, based on the rationale presented above, the City of Pasadena has determined that an MND in accordance with CEQA is the appropriate environmental document for the Project. 1 Responses to Comments
Explorer Well Project
Final IS/MND
Comment I.etter
From:

Stnt:

To:

Cc:

Subject:

Schmitz, ton
Wednesday. February 28, 2024 8:52 AM
Giang. JohnathanGallon, Celine
City of Pasadena. Explorer Well. CEQA/NEPA Coordination IIAl CAUTION: This email was delivered from the Inlerntl Do not click linki or op«n anachments unless you know Ihe content is[safe Report phish using the Phish Alert Button.

Johnathan,
Thanks for the discussion on the City o( Pasadena Explorer Welt Project on Monday and for following up with NASA to find out if they need to do a joint document or if they will be doing a separate document (and ifthey are doing a separate document, that there is not conflicting information on the Project).

I also noticed it was unclear if the Project falls within an active wash so maybe NASA has a delineated study they may have done in the past that clarifies this because of the Project work they have done in the area wherethey would have needed/or need to identify impacts on waters. as the document didn't really reference anystudy when talking about what qualified tor Waters of the US and Waters o( State. but the geology sectionmentioned it fell in an alluvial wash and/or alluvial valley. If it is an active alluvial wash area then the RegionalBoard would need to issue a permit for the Project.

Thanks for following up on these issues!
Please let us know what you find out after talking with NASA! tori Schmitz
Lori SchmteState Water Resources Control Board
Division of Financial AssistanceSpecial Project Review Unit 2 Responses to Comments
Explorer Well Project
Final IS/MND
Response to Comment Letter 1:Response 1-1: The commenter asks if NASA is preparing a joint document, or if NASA will bepreparing a separate document.

The only environmental document that is being prepared for the proposed project is the subject IS/MND. The project does not involve any federal permitting, federal funding, or federal lands.

Therefore, the National Environmental Policy Act (NEPA) does not apply to the project.

Response 1-2: The commenter asks if the project would be located within an active wash. In July2023, the City's consulting biologist conducted a general biological resources survey and habitatassessment for the project, during which the biologist confirmed that the project site contained no jurisdictional waters. Furthermore, the Jurisdictional Delineation Report that was prepared for the Arroyo Seco Canyon Project, which includes the project site, did not identify any jurisdictionalwaters within the project site. Therefore, no permitting pursuant to Sections 401 or 404 of the Clean Water Act would be required for the project and NEPA does not apply. 3 Responses to Comments
Explorer Well Project
Final IS/MND
Comment Letter 2
From:

Sent:

To:

Cc:Subject:

Attachments:

Darrcn Dowcll
Monday, March 4. 2024 8:38 PMGiang, Johnathan
Morales, MargoRe: comment on Explorer Well Project
trail_crossing.explorer.road,202')0303.jpeg
You don't often 9&t ernait from [email protected]> t.ft^rQ ^'t)yth,fijAJirr'P<:ilTW!t |(Al CAUTION: This email was delivered from the Internet Do not click linki or open attachments unless you know the content is[safe Report phish using tht Phish Alert Button Lwtn mqt? This message contains the attachment for the prior comment. Thank you for including with the comment.Darren DowellOn Monday. March 4. 2024 at 07:38:38 PM PST. Darren Dowell <dowell [email protected]> wrote:
to: Johnathan Giang. Case Manager. Explorer Well Projectfrom: C. Darren Dowell. resident of Pasadena (district 5)Johnathan:Thank you for the opportunity to comment on the Explorer Well Project. I found some errors and mischaracterizations in the IS/MND that should be corrected prior to review and implementation of the project.

The project design, exhibit 3-2, correctly notes a trail ("horse trail") through the proposed project area.but the IS/MND completely fails to note other aspects of the trait. As shown in the attachedphoto, the trail after crossing Explorer Road is lined with native plants, likely from an earlier parkproject intended to preserve the natural character as the trail from uphill traverses this area andconnects with the trail system in the park. The plants were severely damaged by a landscape crewaround the last year JPL used this area for parking, but they have partially grown back. The trail isused by hikers and runners more than horses, and, as an important connector, appears on theHahamongna Watershed Park Master Plan The well project would be removing some of the native plantings permanently due to the roadrealignment and may have a temporary impact on them elsewhere. but this is not mentioned in theIS/MND The project should consult with Pasadena Parks staff with knowledge of the intent of thepast planting project and implement some compensation for the loss of these plantings — forexample, restoring the native plantings further to the west of the well project area to their former,intended condition and/or adding someplantinc|stQtheeastolfthe_roa(i_Appallingly, the IS/MND characterizes the site only as lacking "vegetation other than scatterednon-native weeds". The native plantings mentioned above — visible on a satellite photo, andnoticeable in even the must cursory glance at the project site — clearly refute the claim. Some of thenative plants were placed on the proposed project site in the past park project, but others haveappeared on their own as a result of the pavement removal several years ago toward the long-term 1 4 Responses to Comments
Explorer Well Project
Final IS/MND
Comment Letter 2 - continued
goal of recovering the natural state of the area. In a quick look around on March 3, 2024,1 was ableto find the following 9 native plant species present on the proposed project site (photos available onrequest):- Acmispon glaber, mature plants- Artemisia californica, mature plants- Baccharis salicifolia, 5+ feet high- Camissonia sp.- Datura wrightii, mature plants- Eriogonum fasciculatum, mature plants- Hesperoyucca whipplei (probable; seedling)- Heterotheca grandiflora, mature plants, some in bloom- Phacelia distans, mature plants, some in bloom 2-3|cont.

I don't dispute the need for the well project, but it will clearly be an eyesore and sound annoyance forthe long term, as the existing wells demonstrate. Given the park setting, with natural areas verynearby, the proposed project needs to be more respectful of its location. It can start by appropriatelypreserving the native plants bordering the connector trail, as I outlined above.

Sincerely,C. Darren DowellPasadena resident
2 5 Responses to Comments
Explorer Well Project
Final IS/MND
Response to Comment Letter 2:Response 2-1: The commenter states that the Draft IS/MND does not discuss some aspects of the existing horse trail that traverses the northern portion of the project site. The commenter adds that the trail is used by hikers and runners more than horses and that it is lined by strips of native plants that may have been previously planted there. The commenter notes that these plants were recently damaged. This comment is acknowledged, including the fact that the existing horse trailis used by additional users, that it is part of a network of trails that traverses the hlahamongna Watershed Park, and that there is a small patch of disturbed native plants in the northern portionof the project site along the trail that would be removed by the project. No further action required per this comment.Response 2-2: The commenter states that the project would remove some of the native plantings at this location and requests that coordination occur with Pasadena Parks staff to decide upon compensatory mitigation. This comment is acknowledged; however, it has been determined thatthese limited vegetation removal activities would not result in a significant impact pursuant to CEQA given this vegetation does not contain habitat for species identified as sensitive or specialstatus. Therefore, no mitigation is required for the limited vegetation removal that is proposed(less than a tenth of an acre). It is worth noting that the Explorer Well Project site also lies within the larger boundaries of Pasadena's Arroyo Seco Canyon Project which will require demolition and clearing of this area for the expansion of spreading basins, and that there will be landscapingimprovements implemented as part of that project..

Response 2-3: The commenter states that the Draft IS/MND did not describe the existence of native plantings within the project site and that these plants would need to be removed by theproject. This comment is acknowledged, and minor clarifications have been made to the IS/MND to further amplify this information. See Section 2.0 for these clarifications.Response 2-4: The commenter concludes the email expressing support for the project. Thiscomment is acknowledged, and no further response is required. 6 Responses to Comments
Explorer Well Project
Final IS/MND
Comment Letter 3
From: Schmiti, Lori
Sent: Wednesday, February 21, 2024 12:58 PM
To: Boman, Brad
Cc: Wong. Karen@Waterboards Diep, Chi
Subject: City of Pasadena, Explorer Well Project , Behner Treatment Plant Changes? |[A1 CAUTION: This email was delrvered from the Intefntt Do not clkk Bnks or open attachments unless you <rnoi» the content is|safe Report phish using the Phish Alert Bunon. ^;' I_'^_L>— Brad,
I help out the State Water Resources Control Board, Division of Drinking Water with their CEQA for water supply permits. I recently noticed your agency was circulating an initial study/mitigated negative declaration for a new well here: h'ttos ,' ceijar.et opr.c.'i ciov 20?40?()158 or by searching the CEQANet State Clearinghouse website for State Clearinghouse number 2024020158.

The Project involves construction of a new groundwater production well and its connection to the Monk Hill Water Treatment Plant (MHWTP) to optimize removal of perchlorate and VOCs from what is referred to as the "mid-plume' area of contamination in the underlying aquifer. The Projectcomponents include a new well, an 800-foot segment of raw water pipeline, and outlet pipes toexisting basins.While reviewing the document I also noticed the Geotechnical Report from 2018 included plans forchanges to a Behner Treatment Plant:
• To install new vessels on the south end of the plant on an existing reinforced concrete mat that supports existing vessels, which are to be removed (PDF page 223). "The current Behner chemical storage area will be modified to house new ion-exchange and liquid-phase granular activated carbon (LGAC) treatment vessels. These vessels are expected to have an 8-foot-diameter footprint, weighing 10-kips or less. One possibility will be to installboth vessels atop an existing mat foundation, which is currently supporting 8-foot-high, 12-footdiameter "caustic soda" and "alum" storage tanks. Grade changes are not expected to berequired at this plant, and the intent is to salvage the existing reportedly 8-inch-thickelongated-octagonal mat supporting these existing tanks. December 7, 1971 "As Built" plansby James M. Montgomery show that this 8-inch-thick mat foundation is reinforced with No. 4 bars spaced 12-inches on center "both ways.' (PDF page 223-224) I noticed in our records that the Behner Treatment Plant is inactive and also noticed this report wasfrom 2018.1 just wanted to check in to see if the City of Pasadena have current plans to make updates to the Behner Treatment Plant? These or others? 7 Responses to Comments
Explorer Well Project
Final IS/MND
Comment Letter 3 - Continued
Thanks for your response on this!Lori SchmitzLori Schmitz State Water Resources Control BoardDivision of Financial AssistanceSpecial Project Review Unit 2 8 Responses to Comments
Explorer Well Project
Final IS/MND
Response to Comment Letter 3:Response 3-1: The commenter asks if there are current plans to update the Behner Water Treatment Plant. This comment is acknowledged. It is not within the scope of the proposed projectto make any upgrades or modifications to the Behner Water Treatment Plant.. No further response is required.
9 Responses to Comments
Explorer Well Project
Final IS/MND
SECTION 2.0

ERRATA (CLARIFICATIONS AND REVISIONS)
Any corrections to the IS/MND text, tables, and figures generated either from responses tocomments or independently by the City of Pasadena, are stated in this section of the Final IS/MND. These revisions to the Draft IS/MND are provided to clarify, refine, and provide supplemental information for the Draft IS/MND. Changes may be corrections or clarifications to the text and tables of the original Draft IS/MND. Other changes to the Draft IS/MND clarify the analysis in the Draft IS/MND based upon the information and concerns raised by comments during the public review period. None of the information contained in these revisions constitutessignificant new information or changes to the analysis or conclusions of the Draft IS/MND.The information included in these revisions to the Draft IS/MND that resulted from the publiccomment process does not constitute substantial new information that requires recirculation of the Draft IS/MND pursuant to Section 15088.5 of the State CEQA Guidelines.

The modifications contained in the following pages are in the same order as the informationappears in the Draft IS/MND. Deleted text is shown as strikeout and new text is underlined. Theapplicable page numbers from the Draft IS/MND are also provided where necessary for ease of reference.Section 4.4- Biological Resources.Page 4-20 - under threshold (a) - revised as follows:

As depicted in Exhibit 2b, the Project site is located within a formerly paved parking lot and is partially located within currently paved roadways (Explorer Road and Karl Johnson Parkway). TheProject site lacks vegetation other than a minor patch of disturbed native plants in the northernportion of the site. scattered non-native weeds, and minimal overhanging canopy from adjacent vegetated natural areas. A review of all special status species potentially occurring in the Project region, as reported in the California Natural Diversity Data Base, indicates there is no suitablehabitat to support special status plant or wildlife species within the Project site (Appendix E; Special Status Species Potentially Occurring in the Region). There is limited potential for specialstatus bird species to fly over the Project site, but they would not be expected to utilize the Projectsite for foraging or breeding or any other activity that would result in them using or inhabiting theProject site for extended time.

Page 4 ends

As described above, the Project site surface is generally paved and was formerly a parking area.The site fleneraljy_lacks vegetation other than a minor patch of disturbed native plants in the northern portion of the site, scattered individual weeds, and minimal overhanging canopy from adjacent vegetated natural areas (See Exhibit 2b). Due to the lack of vegetation on the site, noriparian habitat or other sensitive natural community would be impacted by the Project. Although trimming of a few branches overhanging the site and removal of a small patch of disturbed native )Iants may occur as needed, these individual plants do not constitute a community and disturbance would be extremely limited and would not have a measurable effect on any habitat or community. Therefore, the Project would have no impact related to this threshold, and no mitigation is required.
10 Responses to Comments
Explorer Well Project
Final IS/MND

Page 4 ends

The Project site is not expected to support regional wildlife movement due to the Project Site's limited size and location outside of recognized regional wildlife movement corridors. The Arroyo Seco and Hahamongna Watershed Park do provide for local wildlife movement, especially for urban-adapted wildlife such as coyotes, foxes, raccoons, and opossums through the area.However, considering the Project site is a former parking lot, lacks substantial vegetation coverage, and is located outside of recognized regional wildlife movement corridors, it does notsupport regional wildlife movement. As a result, the Project site would not be considered a vitalcomponent to the function of this area for regional wildlife movement. There may be indirecteffects on wildlife movement (e.g., increased noise or dust), but these would be considered negligible and unlikely to affect existing wildlife movement in the watershed. 11 Responses to Comments

APPENDIX A

DRAFT INITIAL STUDY/MITIGATED NEGATIVE DECLARATION
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Initial Study andMitigated Negative Declaration
Explorer Well Project
Prepared for City of Pasadena
Water and Power Department
150 South Los Robles Avenue, #200
Pasadena, California 91101
Prepared by Psomas
225 South Lake Avenue, Suite 1000
Pasadena, California 91101
February 2024
Explorer Well Project
Initial Study/Mitigated Negative Declaration

TABLE OF CONTENTS
Section Page
Section 1.0 Introduction ......................................................................................................1-1

1.1 Purpose of Initial Study/Mitigated Negative Declaration.........................1-11.2 Project Summary.................................................................................... 1-2

1.3 Summary of Environmental Impacts.......................................................1-2 Section 2.0 Environmental Setting .....................................................................................2-1

2.1 Project Location......................................................................................2-1

2.2 Project Background and Need................................................................2-1

2.3 Existing Conditions.................................................................................2-22.4 CEQA Review Process...........................................................................2-4 Section 3.0 Project Description ..........................................................................................3-1

3.1 Project Components...............................................................................3-13.2 Project Demolition and Construction ......................................................3-23.3 Long-Term Operations............................................................................3-5

3.4 Agency Approvals and Permits...............................................................3-5 Section 4.0 Environmental Assessment ............................................................................4-1

4.1 Aesthetics...............................................................................................4-44.2 Agriculture and Forest Resources ..........................................................4-8

4.3 Air Quality.............................................................................................4-10

4.4 Biological Resources............................................................................4-194.5 Cultural Resources...............................................................................4-24

4.6 Energy..................................................................................................4-27

4.7 Geology and Soils.................................................................................4-304.8 Greenhouse Gas Emissions.................................................................4-364.9 Hazards and Hazardous Materials .......................................................4-43

4.10 Hydrology and Water Quality................................................................4-49

4.11 Land Use and Planning ........................................................................4-554.12 Mineral Resources................................................................................4-57

4.13 Noise ....................................................................................................4-59

4.14 Population and Housing........................................................................4-694.15 Public Services.....................................................................................4-71

4.16 Recreation ............................................................................................4-74

4.17 Transportation.......................................................................................4-75 Table of Contents
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.18 Tribal Cultural Resources.....................................................................4-78

4.19 Utilities and Service Systems ...............................................................4-81

4.20 Wildfire..................................................................................................4-84

4.21 Mandatory Findings of Significance......................................................4-86 Section 5.0 Document Preparers and Contributors..........................................................5-1Section 6.0 References........................................................................................................6-1 Page
TABLES
Table
1 Construction Activity Assumptions .................................................................................3-3 2 Agency Approvals and Requirements............................................................................3-53 California and National Ambient Air Quality Standards................................................ 4-114 Designations of Criteria Pollutants in the South CoastAir Basin .................................4-125 SCAQMD Regional Pollutant Significance Thresholds (Ibs/day) .................................4-146 Estimated Maximum Daily Construction Emissions (Ibs/day) ......................................4-15 7 Construction-Phase Localized Significance Threshold Emissions...............................4-16 8 Energy Use During Construction..................................................................................4-289 Global Warming Potentials and Atmospheric Lifetimes................................................4-37 10 City of Pasadena ClimateAction Plan Efficiency Thresholds.......................................4-3911 Estimated GreenHouse Gas Emissions from Construction..........................................4-3912 Estimated Annual GreenHouse Gas Emissions from Project Operation......................4-4013 Estimated Total ProjectAnnual GreenHouse Gas Emissions......................................4-4114 Ambient Noise Level Measurements ...........................................................................4-6015 Construction Noise Levels at Noise-Sensitive Land Uses ...........................................4-6316 Vibration Criteria at Nearest Sensitive Uses................................................................4-66

EXHIBITS
Exhibit Follows Page
2-1 Regional Location Map ..................................................................................................2-12-2 Aerial Photograph ..........................................................................................................2-13-1 General Site Plan...........................................................................................................3-1 3-2 Explorer Well Site Plan...................................................................................................3-1 3-3 Explorer Road Realignment...........................................................................................3-1 3-4 Building Elevations.........................................................................................................3-1 3-5 General Slide and Gate Details......................................................................................3-1 3-6 Well Sections ................................................................................................................3-2 4-1 Noise Monitoring Locations..........................................................................................4-604-2 Noise Modeling Results for Nighttime Drilling with No Noise Protection......................4-644-3 Noise Modeling Levels for Nighttime Drilling with No Noise Protection .......................4-644-4 Noise Modeling Results for Nighttime Drilling with Noise Protection ...........................4-644-5 Noise Modeling Levels for Nighttime Drilling with Noise Protection.............................4-64 Table of Contents
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Appendix

APPENDICES
A Air Quality Calculations
B Energy Calculations
C Geotechnical Report
D Noise CalculationsE Special Status Species Potentially Occurring in the Region iii Table of Contents
Explorer Well Project
Initial Study/Mitigated Negative Declaration
SECTION 1.0 INTRODUCTION

1.1 PURPOSE OF INITIAL STUDY/MITIGATED NEGATIVE DECLARATION The California Environmental Quality Act (CEQA) (California Public Resources Code §21000 etseq.) and the State CEQA Guidelines (California Code of Regulations, Title 14, §15000 et seq.) require that local government agencies, prior to taking action on projects requiring discretionary approval, consider the environmental consequences of such projects. In accordance with CEQA,this Initial Study (IS) has been prepared as documentation to support a Mitigated Negative Declaration (MND) for the Explorer Well Project (hereinafter referred to as the "Project") proposed by the City of Pasadena (City). This IS/MND includes a description of the Project; the location of the Project site; an evaluation of the potential environmental impacts of Project implementation; and recommended mitigation measures to lessen or avoid impacts on the environment.

Pursuant to Section 15367 of the State CEQA Guidelines, the City is the Lead Agency for theProject. This Project is being implemented under a partnership between the City and the National Aeronautics and Space Administration's (NASA) Jet Propulsion Laboratory (JPL) campus.

However, the City is the Lead Agency, as it has the principal responsibility for carrying out theProject and has the authority for approving the Project and its accompanying environmental documentation.

In addition to addressing the potential environmental impacts that would result from the Project, this IS/MND serves as the primary environmental document for future activities associated withthe Project, including discretionary approvals requested or required for Project implementation.The Project proposes to install a new extraction well to enhance the removal of contaminantsfrom the groundwater. Pasadena Water and Power (PWP) operates four existing water productionwells associated with a contaminant plume cleanup as part of the Monk Hill Treatment System (MHTS). Adding a fifth well will further reduce levels of perchlorate and volatile organic compounds (VOCs) in the groundwater plume that originated from historic operations at JPL.As part of the evaluation of potential environmental impacts associated with Project implementation, the IS/MND identifies regulatory requirements (RR) applicable to the Project and sets forth mitigation measures (MM) that would lessen or avoid significant impacts on theenvironment. The IS/MND concludes that, while implementation of the Project would haveenvironmental impacts, MMs have been incorporated that would reduce all identified impacts tolevels considered less than significant (Section 15070 of the State CEQA Guidelines). Therefore,an MND is the appropriate CEQA documentation. The reader is referred to the full text of this IS/MND and the technical appendices for a complete discussion and analysis of the Project's potential environmental effects.

As the Lead Agency, the City has commissioned the preparation of this IS/MND and has reviewed and revised, as necessary, all submitted drafts and technical studies to reflect its independent judgment, including reliance on City staff for the review of all technical subconsultant reports. Data for this IS/MND was obtained from on-site field observations; discussions with affected agencies; review of available technical studies, reports, guidelines, and data; and review of specialized environmental assessments prepared for the Project.
1-1 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration

1.2 PROJECT SUMMARY
The Project proposes the construction and operation of two primary components as noted below.

1. Explorer Well: The Explorer Well would be constructed to draw groundwater that is contaminated with perchlorate and VOCs from the aquifer. The water would be pumped from the Explorer Well to the Monk Hill Water Treatment Plant (MHWTP) for treatment.

2. Pipeline: A 12-inch raw water pipeline would be constructed that would connect the Explorer Well to the MHTS. The Project would also include a tee on the pipeline that would outlet water that is produced during the well startup process into an existingspreading basin to the west ofArroyo Well.

1.3 SUMMARY OF ENVIRONMENTAL IMPACTSThe Project would have no impacts related to agriculture and forest resources.

The Project would have less than significant impacts related to aesthetics; air quality; energy;greenhouse gas emissions; hydrology and water quality; land use and planning; mineralresources; population and housing; public services; recreation; transportation; utilities and servicesystems; and wildfire.

The Project would have less than significant impacts with implementation of mitigation measures related to biological resources; cultural resources; geology and soils; hazards and hazardous materials; noise; and tribal cultural resources.The following regulatory requirements and mitigation measures would be implemented by the Project.

Air QualityRRAQ-1RRAQ-2
Construction activities must be conducted in compliance with the South Coast Air Quality Management District's (SCAQMD's) Rule 403, Fugitive Dust, which requires the implementation of best available control measures (BACM) for anyactivity or man-made condition capable of generating fugitive dust including, butnot limited to, earth-moving activities, construction/demolition activities, disturbedsurface area, or heavy- and light-duty vehicular movement. The BACMs includestabilizing soil; watering surface soils and crushed materials; covering hauls orproviding freeboard; preventing track-out; and limiting vehicle speeds and windbarriers, among others.In accordance with the City's Climate Action Plan, construction equipment and vehicles are required to limit idling times to no more than three consecutive minutes.

Biological ResourcesMM BIO-1 Prior to the start of construction of the Explorer Well portion of the Project, an exclusionary fence shall be installed to prevent coastal whiptail from entering thework area. The fence shall be installed along the eastern edge of the projectdisturbance limits at the Explorer Well, which is located at the toe of the vegetatedslope. The exclusionary fencing shall consist of silt fencing, buried six inches deepwhere feasible and installed with no gaps in the fencing. Fencing shall be installed 1-2 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration
under the supervision of a qualified Biologist to ensure that wildlife are notimpacted during installation of the fence. Exclusionary fencing shall be maintained throughout construction of the Explorer Well and shall be removed upon completion of the Explorer Well construction activities.

BIO-2 If feasible, project construction shall be conducted between September 16 and January 31, which is outside the bird nesting season. Construction conductedwithin this period shall be considered in compliance with the conditions set forth inthe Migratory Bird Treaty Act (MBTA) and California Fish and Game Code with methods approved by the U.S. Fish and Wildlife Service (USFWS) and CaliforniaDepartment of Fish and Wildlife (CDFW) to protect active bird and raptor nests. If the nature of the proposed construction activities requires that work be conductedduring the breeding season for nesting birds (March 15-September 15) or nesting raptors (February 1-June 30), to avoid direct impacts on active nests, apre-construction survey shall be conducted by a qualified Biologist for nesting birds and/or raptors within 3 days prior to any construction or disturbance activities (i.e., within 300 feet for nesting birds and within 500 feet for nesting raptors). If the Biologist does not find any active nests within or immediately adjacent to the impact area, the construction work shall be allowed to proceed. If a lapse of morethan three days occurs between outdoor disturbance activities, the nesting bird survey will need to be repeated as nesting activities may potentially occur in that time frame. Results of the surveys will be provided to the City and to CDFW.

If the Biologist finds an active nest within or immediately adjacent to the construction area and determines that the nest may be impacted or breedingactivities substantially disrupted, the Biologist shall delineate an appropriate buffer zone (at a minimum of 25 feet) around the nest depending on the sensitivity of the species and the nature of the construction activity. Any nest found during surveyefforts shall be mapped on the construction plans. The active nest shall be protected until nesting activity has ended. To protect any nest site, the following restrictions to construction activities shall be required until nests are no longeractive, as determined by a qualified Biologist: (1) clearing limits shall beestablished within a buffer around any occupied nest (the buffer shall be 25-100 feet for nesting birds and 300-500 feet for nesting raptors), unless otherwisedetermined by a qualified Biologist and (2) access and surveying shall be restrictedwithin the buffer of any occupied nest, unless otherwise determined by a qualified Biologist. Encroachment into the buffer area around a known nest shall only be allowed if the Biologist determines that the proposed activity would not disturb the nest occupants. Construction can proceed when the qualified Biologist has determined that fledglings have left the nest or the nest has failed.

Cultural Resources
RR CUL-1 If human remains are encountered during excavation activities, all work is required to halt in the immediate vicinity of the discovery and the County Coroner must be notified (California Public Resources Code §5097.98). The Coroner is required to determine whether the remains are of forensic interest. If the Coroner, with the aidof an archaeologist, determines that the remains are prehistoric, they are required to contact the Native American Heritage Commission (NAHC). The NAHC is responsible for designating the most likely descendant (MLD), who is responsible for the ultimate disposition of the remains, as required by Section 7050.5 of the California Health and Safety Code. The MLD is required to make their recommendation within 48 hours of being granted access to the site. The MLD's 1 -3 Environmental Setting
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Initial Study/Mitigated Negative Declaration
recommendation is required to be followed, if determined by the landowner to be feasible, and may include scientific removal and non-destructive analysis of thehuman remains and any items associated with Native American burials (California Health and Safety Code §7050.5). If the landowner rejects the MLD's recommendations, at a minimum the landowner is required to rebury the remains with appropriate dignity on the property in a location that will not be subject tofurther subsurface disturbance (California Public Resources Code §5097.98).

MM CUL-1 Prior to commencement of earthmoving activities, the City shall retain a qualified Archaeologist meeting the Secretary of the Interior's Professional Qualification Standards for Archaeology. The Archaeologist shall be present at the pre-gradeconference; shall establish procedures for archaeological resource surveillance;and shall establish, in cooperation with the Contractor, procedures for temporarily halting or redirecting work to permit the sampling, identification, and evaluation of the artifacts, as appropriate. At a minimum, in the event archaeological resources are exposed during construction activities, all construction work occurring within 100 feet of the find shall immediately stop until a qualified archaeologist can evaluate the significance of the find and determine whether additional study iswarranted. The Archaeologist shall first determine whether it is a "uniquearchaeological resource" pursuant to the California Environmental Quality Act(CEQA, i.e., Section 21083.2[g] of the California Public Resources Code) or a"historical resource" pursuant to Section 15064.5(a) of the State CEQA Guidelines.

If the archaeological resource is determined to be a "unique archaeologicalresource" or a "historical resource", the Archaeologist shall formulate a mitigation plan in consultation with the City of Pasadena that satisfies the requirements of the above-referenced sections. The Archaeologist shall prepare a report of the resultsof any study prepared as part of a testing or mitigation plan, following guidelines of the California Office of Historic Preservation, and they shall record the site andsubmit the recordation form to the City of Pasadena and the California HistoricResources Information System (ChlRIS) at the South Central Coastal InformationCenter (SCCIC) at California State University, Fullerton. Work may proceed inother areas of the site, subject to the direction of the Archaeologist.

Geoloav and Soils
RR GEO-1 Grading, excavation, and construction is required to comply with the City's Building Code (Title 14 of the Pasadena Municipal Code, which incorporates the California Building Code), as they relate to site preparation and construction; alteration; moving; demolition; repair; use and occupancy of buildings; structures and building service equipment within the City. The California Building Code requires the preparation of engineering geologic reports, supplemental ground-responsereports, and/or geotechnical reports for all new construction; new structures on existing sites; and alterations to existing buildings. It also includes seismic design criteria and requirements for use in the structural design of buildings (i.e., based on seismic hazard maps and the seismic design category) and specifies buildingcomponents that require special seismic certification.

GEO-1 Prior to commencement of earthmoving activities, the City shall retain a qualified Paleontologist, for on-call services in the event of a discovery of paleontologicallysensitive rock formations (i.e., Quaternary older alluvial sediments) during ground disturbance activities. The Paleontologist shall be present at the pre-grade conference; and shall establish, in cooperation with the Contractor, procedures for temporarily halting or redirecting work to permit the sampling, identification, and 1-4 Environmental Setting
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Initial Study/Mitigated Negative Declaration
evaluation of any discovered paleontological resources. Should these resources be found during ground-disturbing activities for the Project, the Paleontologist shall first determine whether it is a significant paleontologically sensitive fossil locality or rock formation. If the above-mentioned resources are found during earthmovingactivities, the Paleontologist shall formulate a report and a mitigation plan in consultation with the City of Pasadena. For paleontological resources, thedisposition of the resources shall be subject to approval by the City. All recovered paleontologically sensitive fossils and rock formations shall be deposited in an accredited institution or museum, such as the Natural History Museum of LosAngeles County. If resources are discovered, work may proceed in other areas ofthe Project site, subject to the direction of the Paleontologist.

Hazards and Hazardous Materials
RR HAZ-1 Construction activities are required to comply with existing federal, State, and local regulations regarding hazardous material use, storage, disposal, and transport toprevent risks to public health and safety, including but not limited to regulations set forth by the U.S. Environmental Protection Agency; U.S. Department ofTransportation (CFR Title 49, Hazardous Materials Transportation Act; and Title 40 261.31, 261.21, and 261.24); Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) (40 CFR parts 300, 311, 355, 370,and373); Resource Conservation and Recovery Act (RCRA) (40 CFR parts 240-299); Toxic Substances Control Act (40 CFR parts 745, 761 and 763); California Department of Toxic Substances Control (DTSC); California Department of Transportation (Caltrans); California Division of Drinking Water; and the California Occupational Safety and Health Administration (CalOSHA). All onsite generated waste during both construction and operation that meets hazardous waste criteriawill be stored, manifested, transported, and disposed of in accordance withapplicable regulations and in a manner to the satisfaction of the local Certified Unified Program Agency (CUPA).

HAZ-1 During the drilling of the Explorer Well, the drill cuttings and mud shall be placed directly into California Department of Transportation-approved soil bins and the bins would be temporarily stored on site. Waste samples from these containers shall be analyzed for the "medium-specific parameters" presented in the Samplingand Analysis Plan in NASA'S 2009 Final Remedial Design/Remedial Action(RD/RA) Work Plan, prepared in accordance with CERCLA requirements. Basedon the laboratory results, the waste shall be classified as hazardous ornon-hazardous and waste profiles and manifests for the waste shall be prepared.

The City shall coordinate with NASA to ensure the selection of a U.S.

Environmental Protection Agency (EPA)-certified waste disposal facility and a licensed transporter to haul off the waste.

HAZ-2 During all earthmoving and construction activities, the City shall require the Contractors to implement the following measures:

Trucks and equipment entering the site shall be inspected to be free from oil,gasoline, or other vehicle fluid leaks.

Equipment fueling areas shall be located outside of the spreading basins and any jurisdictional waters as identified by the United States Army Corps of Engineers (USAGE) and the California Department of Fish and Wildlife (CDFW).
1-5 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration
• Any hazardous material spills and/or contaminated soils shall be excavated immediately upon discovery and tested prior to disposal to ensure proper handling and transport in compliance with applicable federal, State, and local regulations governing the handling of hazardous materials.

The Contractor shall maintain hazardous materials spill control, containment, and cleanup kits of adequate size and materials for potential accidental spillsand releases.

Hydroloav and Water Quality
RR HYD-1 The Explorer Well would be operated in compliance with Section 64560 of the California Code of Regulations, which provides requirements associated withinstallation of new drinking water production wells and is administered by theCalifornia Division of Drinking Water (DDW). The new well must also comply with DDW-specified minimum horizontal distances to sanitary hazards. Additionally, the proposed well is required to comply with the community water system wellrequirements in the California Department of Water Resources Bulletins 74-81 and 74-90 and the American Water Works Associated Standard A100-06 (Water Wells).

NoiseRR N01-1 In accordance with Section 9.36.080 of the City of Pasadena Municipal Code, it is unlawful for any person to operate any powered construction equipment if theoperation of such equipment emits noise at a level in excess of 85 A-weighteddecibels (dBA) when measured within a radius of 100 feet from such equipment.

N01-1 The Construction Contractor shall implement the following noise reduction measures during all construction activities:
a. All stationary or mobile construction equipment shall be equipped with properly operating and maintained mufflers and engine enclosures, compliant with or exceeding manufacturers' standards.
b. All construction equipment engine enclosures and covers, as provided by manufacturers, shall be in place during construction activities. c. All construction equipment shall be shut down when not in use.

Construction equipment shall not be allowed to idle for more than 3minutes. d. During Project construction, export of drill cuttings via trucks shall be limited to the hours of 7 AM through 7 PM.
e. For nighttime activities, construction-standard high-pitch backup alarms for construction equipment and vehicles shall not be used during constructionof the Project. Construction equipment and vehicles shall use low-impactbackup alarms, including, but not limited to, the following: manuallyadjustable alarms, self-adjusting alarms, and broadband (white noise) 1-6 Environmental Setting
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Initial Study/Mitigated Negative Declaration
alarms. These alarms shall conform to the safety requirements establishedby the Occupational Safety and Health Administration (OShfA).

N01-2 During nighttime construction activity (i.e., from 7 PM to 7 AM), the Construction Contractor shall ensure that the following best management practices for sound barriers are implemented:
a. Sound barrier enclosures of a minimum height of 12 feet shall enclose all stationary equipment sources of noise on four sides. These enclosuresshall be constructed of either 3/4-inch plywood or greater thickness or soundblankets with a minimum sound transmission class (STC) rating of 25 andcover all sides as well as the top of the equipment. Minimal gaps in theenclosure are acceptable to ensure adequate air intake, exhaust ventilation, and heat dissipation for proper equipment functioning. b. Temporary sediment settling tanks (i.e., Baker tanks) shall be strategically placed between the circulation tank motor and the nearest residential use.

MM N01-3 Prior to commencement of nighttime Project construction, the City of Pasadena shall establish a designated phone hotline and email address for Project-related information and complaints from the surrounding neighborhood. The City shall designate a Noise Complaint Manager to monitor this phone hotline and email.

Fliers or posters must be posted and visible at the Project boundary at least one week prior to commencement of nighttime construction activity and continue throughout the nighttime construction duration. These posters must provide thefollowing information: nighttime construction duration and other related details and contact information for the phone hotline and email address.

MM N01-4 Prior to commencement of nighttime construction activities, the City shall retain a Noise Monitor to monitor noise levels during nighttime construction activities (i.e., from 7 PM to 7 AM). The Noise Monitor shall monitor and record noise at the property line for the nearest residential uses (west and east of the Project site) toensure that noise levels from the Project construction site do not exceed 50 A-weighted decibels (dBA) at night. If Project-related noise levels exceed 50 dBAduring nighttime activities, additional noise reduction measures shall be implemented to further reduce construction noise at the Project site to a level at orbelow 50 dBA, such as additional vertical and horizontal sound barriers.

Public ServicesRR PS-1 The Project shall be designed and constructed in accordance with the Pasadena Fire Prevention Code (Chapter 14.28 of the City's Municipal Code), which adopts the California Fire Code with changes and additions to the adopted code.

Transportatio n
RRTRA-1 Construction activities will be conducted in accordance with the Standard Specifications for Public Works Construction (Greenback) and the City'sSupplements and Modifications to the Greenbook to maintain access to all parcels in and near the construction sites. This includes notification of residents and 1 -7 Environmental Setting
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Initial Study/Mitigated Negative Declaration
businesses affected by the road work; utility agencies with facilities in the area; thePasadena Fire and Police Departments; and other emergency service providers.

The Greenbook also requires that access be made available at the end of eachworkday.

RRTRA-2 Temporary traffic control devices and methods used during construction are required to conform to the requirements of the latest edition of the Manual on Uniform Traffic Control Devices (MUTCD) and the California Supplement to theMUTCD. The contractor shall provide traffic tapers, traffic control devices,barricading, and signs necessary to ensure driver awareness and safety in construction areas and to assist fire and law enforcement personnel.

Tribal Cultural Resources
MM TCR-1 Retain a Native American Monitor Prior to Commencement of Ground Disturbing Activities: Prior to commencement of ground-disturbing activities, theCity of Pasadena (City) shall retain a Native American Monitor (NAM) from orapproved by the Gabrieleno Band of Mission Indians - Kizh Nation (the "Tribe" or"Kizh") to observe ground-disturbing activities, which may include, but are notlimited to, pavement removal, pot-holing or augering, grubbing, tree removals,boring, grading, excavation, drilling, and trenching, within the Project site.Monitoring by the NAM is only to occur onsite when well drilling is scheduled within50 feet below the ground surface (bgs) and is not to exceed five consecutive working days. The NAM shall complete daily monitoring logs providing descriptions of the day's activities including construction activities, locations, soil, and anycultural materials identified. All discovered tribal cultural resources found duringground-disturbing activities for the Project within 50 feet bgs, shall be temporarilycurated in a secure location on site by the Project Archaeologist (refer to MM-CUL1). If removal of artifacts from the Project site is necessary, each artifact shall becatalogued by the Project Archaeologist, and an inventory will be provided to the NAM upon each addition.

Additionally, a tribal cultural specialist from the Kizh Nation will assess the significance of any Tribal Cultural Resource (TCR) under Assembly Bill 52 of theCalifornia Environmental Quality Act (CEQA). While there is significant overlap between archaeological resources and Tribal Cultural Resource, they are differentprotected resources under CEQA. Provenience is important for determining "significance" for an archaeological resource in order to establish whether it meets the California Register of Historical Resources eligibility criteria, however the same is not true for TCRs. The objects, features, sites, sacred spaces, and landscapesare cosmologically considered living things and are considered significant to thedescendants of those People that left them behind. Therefore, both levels ofsignificance assessments shall be made by both an archaeologist and the Kizh tribal monitor.

Following the completion of the Project, all tribal cultural resources shall bereturned to the Tribe. Following a discovery, at the completion of all grounddisturbing activities, the Project Archaeologist shall formulate a Monitoring Report (refer to MM CUL-1) and submit said report to the City of Pasadena and the SouthCentral Coastal Information Center (SCCIC) located at California State University, Fullerton and the Gabrieleno Band of Mission Indians-Kizh Nation Tribal Government. The report will document all monitoring efforts and involvement of the NAM. The report shall be completed within 60 days of conclusion of all Project 1-8 Environmental Setting
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Initial Study/Mit/gated Negative Declaration
ground-disturbing activities. The disposition of the resources shall be subject to review and approval by the City. If tribal cultural resources are discovered, workmay proceed in other areas of the site, subject to the direction of the Project Archaeologist or NAM.

MM TCR-2 Unanticipated Discovery of Tribal Cultural Resource Objects (NonFunerary/Non-Ceremonial): Upon discovery of a tribal cultural resource within the Project site during Project construction, all construction activities shall cease in the immediate vicinity of the discovery (not less than the surrounding 50 feet)and shall not resume until the find can be assessed. All tribal cultural resourcesunearthed by Project activities shall be evaluated by the Project Archaeologist and the NAM. If the resources are Native American in origin, the consulting tribe will retain it/them in the form and/or manner the tribe deems appropriate, for educational, cultural, and/or historic purposes.

MM TCR-3 Unanticipated Discovery of Native American Human Remains and Associated Funerary or Ceremonial Objects: If human remains and/or grave goods are discovered or recognized at the project sites, all ground disturbanceshall immediately cease, and the county coroner shall be notified per PublicResources Code Section 5097.98, and Health & Safety Code Section 7050.5.

Human remains and grave/burial goods shall be treated alike per California PublicResources Code section 5097.98(d)(1) and (2). Work may continue in other parts of the project sites while evaluation and, if necessary, mitigation takes place (CEQAGuidelines Section 15064.5[f]). Preservation in place (i.e., avoidance) is thepreferred manner of treatment for human remains and/or burial goods. Ifpreservation in place is not feasible, treatment may include implementation ofarchaeological data reqovery excavations to remove the resource along withsubsequent laboratory processing and analysis. Any discovery of humanremains/burial goods that are Native American in origin shall be kept confidential to prevent further disturbance.

Utjlitle^and Service Systems
RR UTIL-1 The Contractor is required to comply with the City's Construction and Demolition Waste Management Ordinance (Chapter 8.62 of the Pasadena Municipal Code), which requires preparation and implementation of a Waste Management Plan that shows how at least 75 percent of construction and demolition debris would bediverted away from landfills. The Waste Management Plan is subject to Cityapproval prior to the start of construction activities, and the Contractor shall providemonthly reports to demonstrate compliance during the construction phase. 1-9 Environmental Setting
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1-10 Environmental Setting
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SECTION 2.0 ENVIRONMENTAL SETTING

2.1 PROJECT LOCATION
The Project site is in the City of Pasadena on land owned by the City in the HahamongnaWatershed of the Arroyo Seco, a 24.9-mile-long tributary to the Los Angeles River. The Project site is located approximately 200 feet east of the Arroyo Seco, approximately 215 feet west ofproperties that are within unincorporated Los Angeles County, and approximately 520 feet east of the JPL property, which is located at 4800 Oak Grove Drive in Pasadena. The Project site is located on and near the former JPL East Parking Lot, which was removed by NASA in 2015 as part of a separate project. The Project site's location is depicted on Exhibit 2-1, Regional LocationMap and Exhibit 2-2, Aerial Photograph.

The Project site can be accessed via Interstate 210 freeway (1-210) by exiting Windsor Avenue and traveling northward for approximately 0.9 miles to its intersection with Ventura Street. From this intersection, the Project site is accessed by traveling approximately 0.5 miles along the northbound Explorer Road, which then continues to the east entrance of the JPL campus. Aportion of the Project is also located along Explorer Road and its intersection with Karl Johnson Parkway, a gated access road, approximately a quarter of a mile north of the Windsor Avenue and Ventura Street intersection.

2.2 PROJECT BACKGROUND AND NEED
Since the mid-1980s, NASA has investigated and subsequently taken action to clean upgroundwater contamination associated with historic waste management practices at the JPL, which was listed by the United States Environmental Protection Agency (USEPA) on the National Priority List of the Comprehensive Environmental Response and Liability Act (CERCLA). The groundwater beneath the JPL and surrounding areas is known to contain contaminants, primarilyperchlorate and carbon tetrachloride (CTC), a VOC.

In 2010, the City amended its existing water supply permit with the California Department of Water Resources, Division of Drinking Water (DDW) to include the Monk Hill Treatment System (MHTS) to provide for the treatment of contaminated groundwater from the Monk Hill subbasin of the Raymond Groundwater Basin and the distribution of the treated water for domestic purposes (Pasadena 2011b). The MHTS includes the MHWTP, which can treat up to 7,000 gallons per minute (gpm) of contaminated water.

Currently, groundwater from the Arroyo Well, Well 52, and Ventura Well is pumped to theequalization sump in the Ventura Booster Station at the site of the Ventura Well. From there, the water is boosted to the MHWTP for treatment. Windsor Well is also connected to the MHTS but is currently non-operational. After treatment, the water flows into the adjacent Windsor Reservoir, which is where the City conducts blending of water supplies in compliance with the City's drinkingwater permit, prior to its distribution to PWP's customers. Water leaving the MHTS cannot exceed any maximum contaminant levels (MCLs) or Notification Levels (NLs) established by the StateWater Resources Control Board (SWRCB) and the MHTS must achieve the treatment goal of non-detect for perchlorate and VOCs (Pasadena 2011 b).In 2014, NASA estimated that the MHTS would need to operate for a minimum of 18 years at an annual cost of approximately 3.5 million dollars to reduce the concentration of contaminants in the aquifer to below then current MCLs. Based on NASA'S Final Optimization Work Plan, dated May 2014 (Optimization Plan), a 40 percent increase in perchlorate and VOC removal is projected with the addition of the proposed Project when including Arroyo, Well 52, and Ventura wells. The 2-1 Environmental Setting
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Initial Study/Mitigated Negative Declaration
objectives of the Optimization Plan, which included both the Project and a new well by Lincoln Avenue Water Company (LAWC) (since completed), include:

Reduce life-cycle costs associated with the MHTS and LAWC system; Optimize system operations and increase mass removal;
Provide flexibility to treatment system operations;Improve system reliability and operability; andEnsure three-dimensional capture and containment of the plume (NASA 2014).

2.3 EXISTING CONDITIONS

GROUNDWATER BASIN
The Raymond Basin is a groundwater aquifer situated on an alluvial valley that coversapproximately 40 square miles and that is bordered by the San Gabriel Mountains on the north;the San Rafael Hills on the west; and the Raymond Fault on the south and east. The Raymond Basin is divided into the Monk Hill subbasin to the west (beneath the Project site), the Santa Anita Subbasin to the east, and the Pasadena subbasin in the central portion. These designations are based on differences in elevation and groundwater flow.

The City's water supplies consist of local groundwater pumped from the Raymond Basin and purchases of imported water. Allocations for the extraction of groundwater supplies are detailed in the Raymond Basin Judgment and include Pasadena's decreed rights to the Monk Hill subbasin and the Pasadena subbasin of the Raymond Basin. The Raymond Basin Management Boardadministers the provisions of the adjudication decree.

In addition to its decreed groundwater pumping rights, the City owns the right to divert surface water, which is currently used for groundwater recharge allowing for pumping credits. PWP diverts its water right from the Arroyo Seco to recharge the underlying Monk Hill subbasin throughspreading basins. These basins are located along the east side of the Devil's Gate Reservoir,upstream of Devil's Gate Dam. PWP may then pump a portion of the recharged volume throughspreading credits, in addition to its decreed groundwater pumping rights. The Project site islocated to the east of the northernmost of these basins.

In the Monk Hill subbasin, concentrations of perchlorate, CTC, and several other contaminants resulted in shutdown of four of PWP's wells between 1997 and 2002: theArroyo Well, Well 52, Ventura Well, and Windsor Well, operated by PWP (Pasadena 2016). In 2011, the MHTS was constructed to treat groundwater from these four wells. The PWP wells, Wells #3, #5 (operatedby LAWC), Wells #4 and #7 (operated by Rubio Canon Land and Water Association) and Well #2 (operated by the Las Flores Water Company), are all within the Monk Hill subbasin, and this source water meets the criteria of an "extremely impaired source", as defined in Process Memo 97-005-R2020 (State Water Board 2020).

The Arroyo Seco Canyon Project is a separate project (also to be completed by PWP) with proposed components near the Project site. The Project is designed to be compatible with the Arroyo Seco Canyon Project in both the short-term and the long-term. However, the Project has independent utility and is not reliant on the future spreading basins or other aspects oftheArroyoSeco Canyon Project to function or operate. 2-2 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration

LAND USE
The Project site is surrounded by theArroyo Seco Canyon and Angeles National Forest (ANF) to the north, which are heavily used passive recreation resources; primarily residential uses, with some commercial and public-serving uses, to the east and south; and the spreading basins, Arroyo Seco drainage, and NASA JPL campus, respectively, to the west. The trailhead for the Gabrielino Trail is located at the Explorer Road/WindsorAvenueA/entura Street intersection; this trail begins as a paved fire road and extends northward for approximately 1.5 miles into theArroyo Seco Canyon and theANF.

The Project site is also located within the Hahamongna Watershed Park. This 300 acres of land is designated as open space and extends from Devil's Gate Dam north into the Arroyo SecoCanyon.

The Explorer Well is located on the former JPL Parking Lot, which was removed by NASA afterthe construction of their parking structure within the JPL campus. The location where the ExplorerWell would be built is previously graded and currently unpaved land except for the paving remaining for the two-lane Explorer Road. An approximate 400-foot segment of the Explorer Road would be relocated around the Explorer Well site as part of the Project to maintain access to the JPL east entrance. The pipeline component of the Project is located primarily in paved sectionsof the Explorer Road and Karl Johnson Parkway.

The Project site is located on a parcel of land that has several existing utilities and other infrastructure related to PWP's water system. These include existing subterranean pipelineslocated primarily in the roadways, groundwater production wells (Arroyo Well, Well 52, and the Ventura Well), booster stations (Arroyo Booster Station and Ventura Booster Station), spreading basins for groundwater infiltration, and the currently non-operational Behner Water Treatment Plant.

Applicable Land Use Plans
City of Pasadena General Plan and Zoning Code
The Project site is on land designated and zoned as Open Space (OS) on the City's Land UsePlan and Zoning Map (Pasadena 2019,2023a).Hahamongna Watershed Park Master Plan The Project site is located within the Hahamongna Watershed Park (HWP), which encompasses approximately 1,300 acres in the Arroyo Seco and extends from Devil's Gate Dam north to the San Gabriel Mountains. The Hahamongna Watershed Park Master Plan (HWPMP) provides a framework for managing the recreation, surface water, habitat resources, and cultural resources in the 300 acres of the HWP extending north from Devil's Gate Dam and into the Arroyo Seco Canyon for the use and enjoyment of the public. Because the Project consists solely of public works infrastructure facilities and does not affect the public parkland within the HWP or develop any structures/facilities that would be publicly accessible, the requirements of the HWPMP arenot applicable to the Project. 2-3 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration

2.4 CEQA REVIEW PROCESS
This IS/MND has been prepared to analyze the impacts associated with construction andoperation of the Project. As the CEQA Lead Agency, the City of Pasadena sent a Notice of Intent to Adopt an MND (N01) to responsible and trustee agencies, interested organizations and individuals, as well as to the State Clearinghouse and the Los Angeles CountyRegistrar-Recorder/County Clerk. The IS/MND and associated technical reports can be viewedonline at the City's website at https://ww5.cityofpasadena.net/ptanning/category/environmentalnotices/. Notices were also posted at the site and in the surrounding neighborhood.

The public review period for this IS/MND has been set from Monday, February 5, 2024 toMonday, March 4, 2024. 2-4 Environmental Setting
Explorer Well Project
Initial Study/Mitigated Negative Declaration
SECTION 3.0 PROJECT DESCRIPTION
The Project involves construction of a new groundwater production well, herein referred to as the Explorer Well, and its connection to the MHTS to optimize removal of perchlorate and VOCs from what is referred to as the "mid-plume" area of contamination in the underlying aquifer. The Project includes a new well, an 800-foot segment of raw water pipeline, and outlet pipes to existing basins.The Project site and its location relative to the MHTS is depicted in Exhibit 3-1 , General Site Plan.

3.1 PROJECT COMPONENTSEXPLORER WELL
Contamination of groundwater in the Monk Hill subbasin is the result of JPL's past practice ofdisposing chemicals into on-site pits. In 2011, the MHWTP was constructed and began treatingcontaminated groundwater pumped from four rehabilitated wells operated by PWP (Pasadena 2011b). In 2014, the NASA Optimization Plan recommended construction of two additional groundwater wells to better intercept the perchlorate and VOCs in the groundwater contaminationplume. Since then, one of these wells has been constructed at the LAWC property. The other well is the Explorer Well. The Explorer Well would provide mid-plume treatment by withdrawinggroundwater from the aquifer and sending it to the existing MHWTP for the removal ofcontaminants. Treated water is then distributed to PWP's water system for potable use.

The proposed Explorer Well is shown in detail in Exhibit 3-2, Explorer Well Site Plan. A chain-linkfence would be constructed around the well site enclosing the well building and transformer.

Because the proposed welt site would be situated within the current alignment of Explorer Road,an approximate 400-foot segment of the road would be realigned as part of the Project and would tie into the existing road so that access to the JPL east gate is maintained. The portion of Explorer Road that would be realigned by the Project is depicted in Exhibit 3-3, Explorer Road Realignment.

The proposed well head, pump and motor, electrical equipment, above-ground piping, fittings, and instruments would be housed in an approximately 36-foot by 16-foot (or approximately 600-square-foot) building as shown in Exhibit 3-4, Building Elevations. The well building and pad-mounted transformer would be enclosed within chain-link fencing. The enclosed area wouldbe approximately 70 feet by 96 feet in size. The enclosed area would be paved and would have gates for entry/exit. Access to the Explorer Well would be provided from Explorer Road via new all-weather driveways that would provide access to the two proposed access gates. The gates and fencing proposed for the Project are depicted in Exhibit 3-5, General Slide and Gate Details.Utilities for the Project would include both water and power service. A new water service will connect to an existing potable water line that traverses the site and will include the installation ofa meter and backftow prevention device to protect the potable water supply. Power will beextended from an approved underground power line to a transformer proposed within the Project site.

The preliminary design for the Explorer Well was recommended in the NASA Optimization Plan and includes a well depth of 675 feet, a casing diameter of 16 inches within a 26-inch borehole, and an estimated pumping capacity of 1,600 gpm. Final well design would occur after the well has been drilled and lithologic logging, geophysical logging, and formation sieve analysis have been completed by a qualified hydrogeologist. The well would be constructed of steel casing; a well motor, pump, and pump assembly; a gravel feed tube, sounding tube (for water level measurement), and air vent; and materials placed in layers within the annular space between the 3-1 Project Description
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Explorer Well Site Plan Exhibit 3-2
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Initial Study/Mitigated Negative Declaration
casing and the borehole wall. The estimated pumping water level for the proposed well is 425 feet below ground surface, and the estimated static water level is 257 feet below ground surface.

These depths would be verified upon welt drilling and used to size the well pump and motor. The Project's well design is depicted in Exhibit 3-6, Well Sections.

Also, temporary piping would be installed for use during well development. Pipes would be installed above ground during construction extending from temporary sediment settling (TSS) tanks to two spreading basins nearby to the west. Temporarily during well development, the drillingwater would be directed to TSS tanks where solids would settle out. Then, the water would either be recirculated back to the well for drilling or would be discharged to a basin using the temporary,at-grade pipes described above.Once the well has been equipped and the raw water pipeline component of the Project is completed, as described in more detail below, water that is produced by the Explorer Well would either be discharged to an existing spreading basin to the west during well startup or to the MHTS for treatment. Under a Statewide NPDES permit (Order WQ 2014-0194-DWQ), flows from community drinking water systems are allowed to be discharged to surface waters subject towaste discharge requirements in the permit. Authorized discharges include groundwater supplywell flushing or pump-to-waste and groundwater well development and testing. As defined in the permit, discharges contained in PWP's spreading basins for groundwater recharge fall under thecategory of beneficial reuse and are not required to be monitored.

PIPELINE
The Project includes the installation of approximately 800-feet of raw water pipeline that wouldconnect the Explorer Well to the MHTS. Raw water is defined as natural water found in theenvironment that has not been treated, and in this case refers to the groundwater withdrawn viathe production wells. The new approximately 800-foot segment of 12-inch diameter raw water pipeline would be constructed from just north of the existing Arroyo Well to Well 52 as part of completing the circuit of water flowing from the wells to the Ventura Booster Station where it would then be pumped to the MHWTP. The 12-inch diameter pipe would be installed within trenches that are dug within the existing paved surfaces and/or shoulders of existing access roads (Explorer Road and Karl Johnson Parkway).

The Project would also include a tee in the design of the new 12-inch raw water pipeline, mentioned above, which would be installed north of the Arroyo Well. This tee would lead to a 12-inch pipe that would outlet into an existing basin to the west. The tee and 12-inch pipe would be installed below ground within a trench. This tee and outlet are being installed to outlet water during the well startup process. Well startup typically involves turning on a well pump and runningthe discharge to waste until the water clears, typically about 30 minutes, before redirecting thewater to the treatment and distribution systems. This improvement would include an air gap, which is a physical separation in the piping to protect the potable water system from backflow/potentiatcontamination.

3.2 PROJECT DEMOLITION AND CONSTRUCTION
Construction of the Project is anticipated to take approximately 21 months, beginning in April 2024and ending in December 2025. Construction hours would comply with Pasadena Municipal CodeChapter 9.36, except for the well drilling activities, which requires an exemption from theconstruction hour limitations for around-the-clock drilling. Continuous drilling and maintenance of the drilling fluid pressure is necessary to avoid collapse of the borehole. Designated staging areaswould be fenced to prevent safety hazards, as well as to deter vandalism and theft. Table 1, 3-2 Project Description
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Explorer Well Project
(06C1/20C3 SAK)R:V;lu)tCtstPASUnikS013201 rap>tiC5tForPNEK_tAlellSecIh>nspdt Explorer Well Project
Initial Study/Mitigated Negative Declaration
Construction Activity Assumptions, summarizes the anticipated construction activities for eachphase of the Project.

TABLE 1

CONSTRUCTION ACTIVITY ASSUMPTIONS
Project Phase
Start/End
Month and
Year
Length of
Activity
Equipment in
Use
Number of
Truckloads
Per Phase
Import
or
Export
Volumes
Explorer Well ConstructionSite Preparation and Mobilization April 2024 - April 2024
8 hours/day; 5days/week
Backhoe,semi-truckwith trailers,drill rigmobilization,crane orgradall,worker trucks 15 250 CY
Noise Barriers April 2024 - July
2024
8 hours/day; 5days/week; 3-week duration
Front endloader,Backhoe, Drillrig, Wellcasing flatbed
0 0
Well Drilling (pilot borehole drilling,temporary zone construction and sampling)
May 2024 -June 2024
24 hours/day;7days/week;
4-weekduration
Drilling rig, aircompressor,
trash pumps,vacuumtrucks, gradall
12 150CY
Water Quality Analysis and FinalWell Design
June 2024 -June 2024
2-weekduration
None 0 0
Well Drilling (continued) (boreholereaming, casing installation) andWell Development June 2024 -July 2024
Well Drilling: 7days/week(24 hours aday) 2.5-weekdurationWellDevelopment:7 days/week(24 hours aday) 1.5weekduration Front endloader,Backhoe, Drillrig, Wellcasingflatbed,Temporarypump andgenerator,Baker tanks(waterstorage) 20 300 CY
Install Test Pump, Well Testing andSampling
August 2024 -September 2024
8 hours/day; 5days/week;4weekduration
Pump rig withtrailer, dieselengine tooperate testpump
0 0
Equipment Installation December 2024
- March 2025
8 hours/day; 5
days/week
Front end
loader,Backhoe, Drillrig, Wellcasing flatbed
0 0
3-3 Project Description
Explorer Well Project
Initial Study/Mitigated Negative Declaration
TABLE 1

CONSTRUCTION ACTIVITY ASSUMPTIONS
Project Phase
Start/End
Month and
Year
Length of
Activity
Equipment in
Use
Number of
Truckloads
Per Phase
Import
or
Export
Volumes
Site Development December 2024
- December2025
8 hours/day; 5days/week
Front endloader,Backhoe,Dump truck,Work trucks
20 300 CY
Pave Site/Asphalt for DrivewayConnections
July 2024-October 2025
8 hours/day; 5days/week
Front endloader,
Backhoe,Dump truck,Work trucks
14 212 CY
Building Construction February 2025 -
April 2025
8 hours/day; 5days/week
Front endloader,Backhoe,Dump truck,Work trucks
3 1.300SF
CMU
Architectural Coatings (painting ofthe building)
May 2025-July2025
8 hours/day; 5days/week
Front endloader,Backhoe,Dump truck,Work trucks
3 1.144SF
Well Discharge PipelineExcavation/Trenching April 2024 - September 2024
8 hours/day; 5days/week
Front endloader, dumptruck,backhoe,work trucks
1 and
16 6CY
and
230 CY
Piping Construction April 2024 -
September 2024
8 hours/day; 5days/week
Front endloader, dumptruck,backhoe,work trucks
1 1 CY
Paving April 2024 -
September 2024
8 hours/day; 5days/week
Front endloader, dumptruck,backhoe,work trucks
4 50 CY
CY: cubic yards; SF: square feet; CMU: concrete-masonry units.

All clean demolition debris and excess soil would be exported to the Scholl Canyon Landfill or to other landfills in the County.Construction workers, equipment delivery vehicles, and haul trucks (to and from Scholl Canyon Landfill) are expected to come to the site from the 1-210 at the WindsorAvenue off-ramp and headnorth on Windsor Avenue to Explorer Road and into the Project site. From 1-210, trucks wouldhead west on State Route (SR) 134; exit at the Figueroa Street/SchoII Canyon Road off-ramp; and head north-northeast toward the landfill. Trucks would come back from the landfill entering the eastbound on-ramp on the SR-134 at Figueroa Street and head east; trucks would then gowest on 1-210 to Windsor Avenue to Explorer Road and, ultimately, to the site. 3-4 Project Description
Explorer Well Project
Initial Study/Mitigated Negative Declaration

3.3 LONG-TERM OPERATIONS
The Explorer Well would be operated continuously and in accordance with the requirements of Pasadena's domestic water supply permit. Future operations would require routine maintenance including daily monitoring by PWP's drinking water system operators, monthly water levelmeasurements, and bi-annual flow meter accuracy tests.

3.4 AGENCY APPROVALS AND PERMITS
This IS/MND is intended to serve as the primary environmental document pursuant to CEQA forthe Explorer Well Project, including all discretionary approvals requested or required to implementthe Project. In addition, this is the primary reference document for the formulation and implementation of a mitigation monitoring program for the Project.

Table 2, Agency Approvals and Requirements, lists all the agencies that are known or expectedto have permit or approval authority over the Project.

TABLE 2

AGENCY APPROVALS AND REQUIREMENTS
Agency Approval/Permit Required Purpose
City of Pasadena
Pasadena Municipal Code(PMC) Exemption1
Allow for round-the-clock constructionactivity during well drilling.

Well Permit Allow for well construction.

State Water Resources Control
Board, Division of Drinking Water
(DDW)
Amendment to Domestic WaterSupply Permit
Allow for operation of a new well inPasadena's drinking water system. 1 A waiver from City construction hour limits was issued by the City Manager for the Project on December 5, 2023.

The City Manager is authorized to exempt construction from those limits imposed by PMC Section 9.36.070,Construction Projects, if the construction serves the best interest of the public and protects the public health, safety,and welfare pursuant to PMC Section 9.36.170, Exemptions. 3-5 Project Description
Explorer Well Project
Initial Study/Mitigated Negative Declaration
This page intentionally left blank
3-6 Project Description
Explorer Well Project
Initial Study/Mitigated Negative Declaration
SECTION 4.0 ENVIRONMENTAL ASSESSMENT
This section includes the completed CEQA environmental checklist form, as provided in AppendixG of the State CEQA Guidelines, as welt as substantiation and clarification for each checklist response. The checklist form is used to assist in evaluating the potential environmental impacts of the Explorer Well Project and identifies whether the Project is expected to have potentiallysignificant adverse impacts.

1. Project Title: Explorer Well Project

2. Lead Agency Name and Address:

3. Contact Person and Phone Number:

4. Project Location:

5. Project Sponsor's Name
and Address:

6. General Plan Designation:

7. Zoning:

City of Pasadena
Department of Water and Power150 South Los Robles Avenue, Suite 200 Pasadena, California 91101Johnathan Giang
626.744.8423
At the former JPL East Parking Lot and north of the
intersection of Windsor Avenue and Ventura Street,in Pasadena, Los Angeles County, California City of Pasadena
Department of Water and Power150 South Los Robles Avenue, Suite 200 Pasadena, California 91101
Open Space, InstitutionalOS (Open Space) and PS (Public, Semi-Public)

8. Description of Project: The Project includes construction of a new well in the Hahamongna Watershed of the Arroyo Seco (in an area that was formerly the JPL East Parking Lot), installed to intercept a groundwater contamination plume (perchlorate and volatile organiccompounds) and a new segment of pipeline to connect the well to the existing Monk Hilt Treatment System (MHTS). See Section 3 for additional details.

9. Surrounding land uses and setting: The areas included in the Project are bound by residential uses in Pasadena and the community of Altadena to the east and south; openspaces in the ANF to the north; Devil's Gate Dam and Reservoir to the southwest; and the Arroyo Seco stream corridor, Oak Grove Park, and other recreational areas, and the JPL campus on the west. See Section 2 for additional details.

10. Other public agencies whose approval is required: State Water Resources Control Board, California Department of Water Resources, Division of Drinking Water (DDW).

11. Have California Native American tribes traditionally and culturally affiliated with the project area requested consultation pursuant to Public Resources Code section 21080.3.1? If so, hasconsultation begun? Tribal consultation has occurred consistent with Assembly Bill 52(AB 52). More information is provided in Section 4.16 of this IS/MND, which addresses tribalcultural resources. 4-1 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED:

The environmental factors checked below would be potentially affected by this Project, involving at least one impact that requires mitigation, as indicated on the following pages.

D Agriculture and Forest Resources
Biological Resources
Energy
D Greenhouse Gas EmissionsD Hydrology and Water Quality Mineral ResourcesPopulation and hlousing
D Recreation
Tribal Cultural Resources
Mandatory Findings of Significance
Aesthetics
a Air Quality
Cultural Resources
IE] Geology and Soils
Hazards and Hazardous MaterialsLand Use and Planning
^ Noise
D Public ServicesD Transportation/Traffic
Utilities and Service Systems
DETERMINATION:

On the basis of this initial evaluation:

I find that the proposed project COULD NOT have a significant effect on the environment, and a NEGATIVE DECLARATION will be prepared.
^] I find that although the proposed project could have a significant effect on the environment, there will not be a significant effect in this case because revisions in the project have been made by or agreed to by the project proponent. A MITIGATED NEGATIVE DECLARATION willbe prepared.

D I find that the proposed project MAY have a significant effect on the environment, and an ENVIRONMENTAL IMPACT REPORT is required.

D I find that the proposed project MAY have a "potentially significant impact" or "potentially significant unless mitigated" impact on the environment, but at least one effect (1) has beenadequately analyzed in an earlier document pursuant to applicable legal standards, and (2) has been addressed by mitigation measures based on the earlier analysis as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the effects that remain to be addressed.

D I find that although the proposed project could have a significant effect on the environment, because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or mitigation measures that are imposed upon the proposed project, nothing further is required.

Signature of Lead Agency Representative Date
City of Pasadena
Printed name AgencyNegative Declaration/Mitigated Negative Declaration adopted on:

Adoption attested to by:

Printed name/Signature Date
4-2 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
EVALUATION OF ENVIRONMENTAL IMPACTS:
1)
2)3)
4)
5)
6)
A brief explanation is required for all answers except "No Impact" answers that are adequately supported by the information sources a lead agency cites in the parentheses following each question. A "No Impact" answer is adequately supported if the referenced information sourcesshow that the impact simply does not apply to projects like the one involved (e.g., the projectfalls outside a fault rupture zone). A "No Impact" answer should be explained where it is basedon project-specific factors as well as general standards (e.g., the project will not exposesensitive receptors to pollutants, based on a project-specific screening analysis).

All answers must take account of the whole action involved, including off-site as well as on-site, cumulative as well as project-level, indirect as well as direct, and construction as wellas operational impacts.Once the lead agency has determined that a particular physical impact may occur, then thechecklist answers must indicate whether the impact is potentially significant, less thansignificant with mitigation, or less than significant. "Potentially Significant Impact' isappropriate if there is substantial evidence that an effect is significant. If there are one or more"Potentially Significant Impact" entries when the determination is made, an EIR is required."Negative Declaration: Less Than Significant With Mitigation Incorporated" applies where the incorporation of mitigation measures has reduced an effect from "Potentially SignificantUnless Mitigation Incorporated" applies where the incorporation of mitigation measures hasreduced an effect from "Potentially Significant Impact" to a "Less Than Significant Impact." The Lead Agency must describe the mitigation measures and briefly explain how they reduce the effect to a less than significant level (mitigation measures from Section 21, "EarlierAnalysis," may be cross-referenced).

Earlier analysis may be used where, pursuant to the tiering, program EIR, or other CEQAprocess, an effect has been adequately analyzed in an earlier EIR or negative declaration.See State CEQA Guidelines Section 15063(c)(3)(D). Earlier analyses are discussed inSection 21 at the end of the checklist.a) Earlier Analysis Used. Identify and state where they are available for review.b) Impacts Adequately Addressed. Identify which effects from the above checklist were within the scope of and adequately analyzed in an earlier document pursuant to applicable legal standards, and state whether such effects were addressed by mitigation measures basedon the earlier analysis. c) Mitigation Measures. For effects that are "Less than Significant with Mitigation Measures Incorporated," describe the mitigation measures which were incorporated or refined from the earlier documents and the extent to which address site-specific conditions for the project.

Lead agencies are encouraged to incorporate into the checklist references to information sources for potential impacts (e.g., general plans, zoning ordinances). Reference to a previously prepared or outside document should, where appropriate, include a reference to the page or pages where the statement is substantiated. 7) Supporting Information Sources: A source list should be attached, and other sources used or individuals contacted should be cited in the discussion. 8) The explanation of each issue should identify:
a) The significance criteria or threshold, if any, used to evaluate each question; andb) The mitigation measure identified, if any, to reduce the impact to less than significant. 4-3 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.1 AESTHETICS
Less Than
Potentially Significant Less Than
Significant with Significant No
Impact Mitigation Impact Impact
Would the project:
a) Have a substantial adverse effect on a scenic vista? Db) Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic Dbuildings within a state scenic highway? c) In non-urbanized areas, would the Project substantially degrade the existing visual character or quality of publicviews of the site and its surroundings (Public views arethose that are experienced from publicly accessible dvantage point)? If the Project is in an urbanized area, would the Project conflict with applicable zoning and
other regulations governing scenic quality?
d) Create a new source of substantial light or glare which would adversely affect day or nighttime views in the D
area?
DD
sD
Ds
D s D
D s D

IMPACT ANALYSIS
Reg u latorv Requirements
There are no regulatory requirements applicable to aesthetics.

Impact Discussion
a) Would the project have a substantial adverse effect on a scenic vista? Less Than Significant Impact. A scenic vista is generally defined as a viewpoint that providesexpansive views of a highly valued landscape for the benefit of the public.

The City's General Plan EIR provides the following description of the existing scenic features andvisual resources in the City: "The City of Pasadena affords a variety of views of scenic landscapes and built environments. The San Gabriel Mountains, near the north City boundary, dominate theskyline from most of the City. The San Rafael hlills are along the western City boundary, and the Verdugo Mountains are further to the west. In addition, the Arroyo Seco corridor and Eaton Canyon traverse the western and eastern portions of the City, respectively. The City also offersscenic views of distinct architecture in the built environment, such as the Old Pasadena HistoricDistrict, Pasadena City Hall, Castle Green, St. Andrew Catholic Church bell tower, and Bungalow Heaven" (City of Pasadena 2015a). The Project site is located near scenic vistas, including viewsof the reservoir behind Devil's Gate, the Arroyo Seco, and the foothills of the San GabrielMountains.

The Project site is visible to trail users of the Gabrielino Trail looking west to the bottom of anapproximate 50-foot embankment. The Project site is also visible from vehicles traveling Explorer Road with the embankment in the background. There are also limited, distant views of the Project site for park users from portions of Hahamongna Watershed Park to the southwest of the Project site, and for trail users on the Fern Truck, Mountain View, and El Prieto Trail Loop. Due to 4-4 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
intermittent topography and development, the Project site is not visible from the Sunset Ridge Trail or the Altadena Crest Trail.

During construction, views of the welt-drilling rig would be present for 24 hours per day for a period of approximately eight weeks. Viewers that would be temporarily affected would include trail andpark users noted above, The well-drilling rig used during construction would be approximately 40 feet tail. The well-drilling rig and other construction equipment would temporarily alter views of vegetation and theArroyo Seco to the west of the Project site for the users of the Gabrielino Trail.

The rig would also alter views to the north and south from Explorer Road. Trail and park userswould temporarily view an active construction site that interrupts and detracts from the natural scenic views as they pass the Project site. However, for these users the temporary altered views would be a minor change given that construction routinely occurs within an urbanized area. From other viewpoints including, Hahamongna Watershed Park and the Fern Truck, Mountain View,and El Prieto Trail Loop, the Project site is further in the distance and views of constructionactivities would be obscured and minimally visible. Therefore, Project construction activities wouldminimally alter these views.Similarly, the temporary at-grade pipes that would be required during construction would not substantially alter views of scenic vistas as these temporary pipes would not require anyvegetation removal. Therefore, given their limited height and because no vegetation would needto be removed, the proposed temporary at-grade pipes would not result in impacts related to scenic vistas.

The Explorer Well and associated well enclosure would be the primary visible aspects of the Project. The new well would include a 10-foot-high chain-link fence that would be installed around the well site. The fence would enclose the new well building and transformer. The new buildingwould be a maximum of 16 feet tall. The Project site is located at the toe of an approximate 50-footembankment with the Gabrielino Trail along the top. Due to this difference in elevation, the Projectwill be minimally noticeable from users of the Gabrielino Trail looking west towards the Arroyo Seco and the JPL campus beyond. For recreators in the open spaces of the Hahamongna Watershed Park, the Project will be viewed from the west and will therefore have the 50-footembankment in the background. For viewers from Explorer Road, views of the embankment andsome of the higher elevations beyond would be partially blocked by the new building, but viewsof the San Gabriel Mountains to the north would not be impacted. Therefore, views of theproposed building from these scenic vantage points would be minimal and fleeting for thosepassing through the Project site as the building would appear to blend in with the landscape andadjacent scattered development.

Therefore, the Project's proposed building to enclose the Explorer Well would result in a less than significant impact related to scenic vistas.

The Project would require the realignment of a 400-foot segment of Explorer Road to accommodate the Explorer Well. These improvements would have minimal visual effects as this work would all occur at- or below-ground level and, thus, would not obstruct any views. The below-grade pipeline installation would not affect scenic vistas since the pipeline improvements would be underground and would not change the visual quality of the Project site as these areas would be backfilled and re-paved prior to the completion of construction.

Therefore, the Project would result in a less than significant impact related to this threshold, andno mitigation is required. 4-5 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
b) Would the project substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway? No Impact. Based on a review of the California Department of Transportation, California ScenicHighway Mapping System, the Project site is not near a designated or eligible State scenichighway (Caltrans 2023). Specifically, the Project site is not visible from SR-2 (an OfficiallyDesignated Scenic Highway) or 1-210 (an Eligible Scenic Highway) due to intervening topography and development. Further, the Project would not require the removal of any trees, rock outcroppings, or historic buildings.

Therefore, the Project would result in no impact related to this threshold, and no mitigation is required.c) In non-urbanized areas, would the Project substantially degrade the existing visual character or quality of public views of the site and its surroundings (Public viewsare those that are experienced from publicly accessible vantage point)? If the Project is in an urbanized area, would the Project conflict with applicable zoning and other regulations governing scenic quality?
Less Than Significant Impact. The Project site is in an urbanized area of the City pursuant toSection 21071 of the State CEQA Guidelines. Given that the Project site is in an urbanized area, the analysis for this threshold focuses on whether the Project would conflict with applicable zoning and other regulations governing scenic quality. The Project site is on land designated and zoned as Open Space (OS) on the City's Land Use Plan and Zoning Map. (Pasadena 2019, 2023a, 2023b).

The proposed Project has been planned in compliance with applicable City regulations related toscenic quality, including maximum building heights. More information related to Projectconsistency with plans, policies, and regulations is provided in Section 4.10, Land Use and Planning. As described in more detail in Section 4.10, the Project would not conflict with the applicable zoning and other regulations governing scenic quality established in the City of Pasadena.Given that the Project would not conflict with applicable zoning and other regulations governingscenic quality, the Project would result in a less than significant impact related to this threshold,and no mitigation is required.d) Would the project create a new source of substantial light or glare which would adversely affect day or nighttime views in the area?
Less Than Significant Impact. During well drilling activities of the Explorer Well, there would bea period of 8 weeks during which drilling activities would occur for 24 hours a day. Lighting wouldbe necessary at this location during nighttime activities. The Gabrielino Trail, Explorer Road, hlahamongna Watershed Park, and Fern Truck, Mountain View and El Prieto Trail Loop, which have views of the Project site, are closed during the evening hours. As such, in the absence of viewers at the said parks and trails, new impacts pertaining to nighttime views would not occur.

During construction, the Project site would be lit more during nighttime hours than in existingconditions, which would be most noticeable for nearby residents. From a distance, the additionallighting would appear similar to the exterior lighting that already exists along nearby roads and at nearby residences in proximity to the Project site. Also, all construction lighting to be used forevening work would be hooded and oriented towards active work areas within the Project site andaway from nearby and adjoining properties and streets. Therefore, nighttime lighting as part of 4-6 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
construction activities would be temporary and result in a less than significant impact, and no mitigation is required.Upon completion, the building containing the Explorer Well would have two exterior lights that would be located above the doors on the east and south sides of the building at a height ofapproximately eight feet above ground. Nighttime views of the Project site from nearby residencesand public roads to the east of the Project site would have views of the new lighting. This new lighting would appear as an extension of the existing lighting within the Project vicinity. The twoproposed exterior lights would be photo controlled exterior LED light fixtures and would be down-cast. The exterior lights that are proposed on the Explorer Well building are similar to theexterior light that already exists in the vicinity of the Project site at the Behner Water Treatment Plant and the Arroyo Well and Booster Station. Therefore, operational lighting would result in aless than significant impact related to this threshold, and no mitigation is required.

Furthermore, as shown on Exhibit 3-4, the Project design does not include any highly reflectivebuilding materials or paints that would result in day-time glare that would be atypical of uses in the Project vicinity. Therefore, the Project would result in a less than significant impact pertainingto glare, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to aesthetics were identified; therefore, no mitigation measures are required.
4-7 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.2 AGRICULTURE AND FOREST

RESOURCES
Less Than
Potentially Significant Less Than
Significant with Significant No
Impact Mitigation Impact Impact
Would the project:
a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on themaps prepared pursuant to the Farmland Mapping andMonitoring Program of the California Resources Agency,to non-agricultural use? b) Conflict with existing zoning for agricultural use, or a Williamson Act contract?
c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code section 12220[g]), timberland (as defined by Public Resources
Code section 4526), or timberland zoned Timberland
Production (as defined by Government Code section
51104[g])?
d) Result in the loss of forest land or conversion of forest land to non-forest use?
e) Involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland, to non-agricultural use or conversion of
forest land to non-forest use?
DD
aDa
D
D
DDa
DD
DDa
^s
sss

IMPACT ANALYSIS
Regulatory RequirementsThere are no regulatory requirements applicable to agriculture and forest resources.

Impact Discussion
a) Would the project convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to theFarmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use?
b) Would the project conflict with existing zoning for agricultural use, or a Williamson Act contract?
e) Would the project involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland to non-agricultural use or conversion of forest land to non-forest use?
No Impact. There are no parcels within the Project site that are currently utilized for agriculture or forestry purposes. According to the California Important Farmland Finder maintained by theCalifornia Depari:ment of Conservation (DOC), the Project site is mapped as Urban and Built-Up Land (DOC 2023a). Therefore, the Project would not result in the conversion of any lands 4-8 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
identified by the DOC as Prime Farmland, Unique Farmland, or Farmland of StatewideImportance Farmland.

The City has no land zoned for agricultural use other than commercial growing areas and land withincertain specific plan areas. The Project site is within the OS, which is not one of the zones that permitscommercial growing areas (Pasadena 2019). Accordingly, there is no agricultural zoning, and no Williamson Act contracts within the City (Pasadena 2015a).

Therefore, the Project would result in no impacts related to these thresholds, and no mitigation is required.c) Would the project conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code, Section 12220[g]), timberland (as defined by Public Resources Code, Section 4526), ortimberland zoned Timberland Production (as defined by Government Code, Section 51104[g])?
d) Would the project result in the loss of forest land or conversion of forest land to non-forest use?
e) Would the project involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland to non-agricultural use or conversion of forest land to non-forest use?
No Impact. There is no timberland, Timberland Production Zones, forest land, or farmland located within the City of Pasadena (Pasadena 2015a). Furthermore, the Project site does not currently contain any forested areas, with only limited tree coverage along its boundaries. As such, the Project would not conflict with the existing zoning for, or cause rezoning of, forest land, timberland, or timberland zoned Timberland Production.Therefore, the Project would result in no impacts related to these thresholds, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to agriculture and forest resources were identified; therefore, nomitigation measures are required. 4-9 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.3 AIR QUALITY Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Where available, the significance criteria established by the applicable air quality management district or air pollutioncontrol district may be relied upon to make the following determinations. Would the project:a) Conflict with or obstruct implementation of the applicable air quality plan?
b) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is in nonattainment under an applicable federal or state ambient air quality standard?
c) Expose sensitive receptors to substantial pollutant
concentrations?
d) Result in other emissions (such as those leading to
odors) adversely affecting a substantial number ofpeople? DD
Da
DD
aD
sss^
DDDa

IMPACT ANALYSIS
Reaulatorv Requirements
RR AQ-1 Construction activities must be conducted in compliance with the South Coast Air Quality Management District's (SCAQMD's) Rule 403, Fugitive Dust, which requires the implementation of best available control measures (BACM) for anyactivity or man-made condition capable of generating fugitive dust including, butnot limited to, earth-moving activities, construction/demolition activities, disturbedsurface area, or heavy- and light-duty vehicular movement. The BACMs includestabilizing soil; watering surface soils and crushed materials; covering hauls or providing freeboard; preventing track-out; and limiting vehicle speeds and windbarriers, among others.

RRAQ-2 In accordance with the City's Climate Action Plan, construction equipment and vehicles are required to limit idling times to no more than three consecutive minutes.

Im pact Discussiona) Would the project conflict with or obstruct implementation of the applicable air quality plan?
Less Than Significant Impact. The Project site is located in the Los Angeles County portion of the South Coast Air Basin (SoCAB) and, for air quality regulation and permitting, is under the jurisdiction of the South Coast Air Quality Management District (SCAQMD). Both the State of California (State) and the U.S. Environmental Protection Agency (USEPA) have established health-based Ambient Air Quality Standards (AAQS) for air pollutants, which are known as "criteriapollutants". The AAQS are designed to protect the health and welfare of the populace within areasonable margin of safety. TheAAQS for ozone (Os), carbon monoxide (CO), nitrogen dioxide(N02), sulfur dioxide (802), inhalable particulate matter with a diameter of 10 microns or less 4-10 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
(PM10), fine particulate matter with a diameter of 2.5 microns or less (PM2.5), and lead are shownin Table 3, California and National Ambient Air Quality Standards.

TABLE 3

CALIFORNIA AND NATIONAL AMBIENT AIR QUALITY STANDARDS
Pollutant Averaging Time
California
Standards
Federal Standards
Primary' Secondary"
03 1 Hour
8 Hour

0.09ppm(180 |jg/m3)

0.070ppm (137 pg/m3) | 0.070 ppm (137 pg/m3) | Same as Primary PM10 24 Hour AAM 50 pg/m3 20 |jg/m3 150 pg/m3 Same as Primary Same as Primary PM2.5 24 Hour
AAM 12 |jg/m3
35 pg/m3 Same as Primary

12.0 Mg/m;,3 15.0 |jg/m3
co
1 Hour8 Hour
20 ppm (23 mg/m3)

9.0ppm (10mg/m3)
35 ppm (40 mg/m3)
9 ppm (10 mg/m3)
8 Hour
(Lake Tahoe) 6 ppm (7 mg/m3)
N02 AAM 1 Hour 0.030 ppm (57 |jg/m3) | 0.053 ppm (100 |jg/m3) | Same as Primary 0.18 ppm (339 |J9/m3) | 0.100 ppm (1 88 pg/m3)S02 24 Hour 0.04ppm (105 pg/m3) 0.14 ppm (for certain areas)0 3 Hour 0.5 ppm (1,300tjg/m3)
1 Hour 0.25 ppm (655 pg/m3) | 0.075 ppm (196 pg/m3)
Lead
30-dayAvg. 1.5 pg/m,3
Calendar Quarter
Rolling
3-month Avg.

1.5 pg/m3

0.15 |jg/m3 Same as Primary
Visibility
Reducing
Particles
Sulfates
Hydrogen
Sulfide
Vinyl
Chloride
8 hour
Extinction coefficient of

0.23 per km - visibility s
10 miles
(0.07 per km-S30 miles
for Lake Tahoe)
24 Hour 25 |jg/m3
1 Hour 0.03 ppm (42 MS/rn3)
24 Hour 0.01 ppm (26 |jg/m3)
No
Federal
Standards
Os: ozone; ppm: parts per million; M9/m3: micrograms per cubic meter; PM10: large particulate matter; AAM: Annual ArithmeticMean; PM2.5: fine particulate matter; CO: carbon monoxide; mg/m3: milligrams per cubic meter; N02: nitrogen dioxide; SO;:sulfur dioxide; km: kilometer; -: No Standard.

National Primary Standards: The levels of air quality necessary, within an adequate margin of safety, to protect the public health.
b National Secondary Standards: The levels of air quality necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.

On June 2, 2010, a new 1-hour SO; standard was established and the existing 24-hourand annual primary standards were revoked. To attain the 1-hour national standard, the 3-year average of the annual 99th percentile of the 1-hour daily maximum concentrations at each site must not exceed 75 ppb. The 1971 S02 national standards (24-hour and annual) remain in effect until one year after an area is designated for the 2010 standard, except that in areas designated nonattainment for the 1971 standards, the 1971 standards remain in effect until implementation plans to attain or maintain the 2010 standards are approved.

Note: More detailed information in the data presented in this table can be found at the CARB website (www.arb.ca.gov).Source: CARB 2016. 4-11 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Regional air quality is defined by whether the area has attained State and federal air quality standards, as determined by air quality data from various monitoring stations. Areas that areconsidered in "nonattainment" are required to prepare plans and implement measures that willbring the region into "attainment". When an area has been reclassified from nonattainment toattainment for a federal standard, the status is identified as "maintenance", and there must be aplan and measures established that will keep the region in attainment for the next ten years.

For the California Air Resources Board (CARB), an "unclassified" designation indicates that the air quality data for the area are incomplete and there are no standards to support a designationof attainment or nonattainment. Table 4, Designations of Criteria Pollutants in the South Coast Air Basin, summarizes the attainment status of the SoCAB for the criteria pollutants.

TABLE 4

DESIGNATIONS OF CRITERIA POLLUTANTS

IN THE SOUTH COAST AIR BASIN
Pollutant State Federal
Os (1 hour) Nonattainment No StandardsOs (8 hour) Nonattainment Extreme Nonattainment PM10 Nonattainment AttainmenVMaintenance
PM2.5 Nonattainment Serious Nonattainment
co Attainment AttainmenVMaintenance
N02 Attainment AttainmentS02 Attainment Attainment
Lead No Standard Attainment/Nonattainment*
All others AttainmenVUnclassified No Standards
Os: ozone; PM10: particulate matter 10 microns or less in diameter; PM2.5: particulate matter 2.5 microns or less indiameter; CO: carbon monoxide; N€2: nitrogen dioxide; S02: sulfur dioxide.

The Los Angeles County portion of the SoCAB is designated nonattainment for lead; the remainder of the SoCAB is designated attainment.

Source: SCAQMD 2017; USEPA2022.

Sensitive Air Quality ReceptorsSensitive receptors include, but are not limited to, children, the elderly, persons with preexisting respiratory or cardiovascular illness, and athletes and others who engage in frequent exercise.

The nearest sensitive receptors to the Project site are single-family residential land uses, whichare located approximately 195 feet to the east of the Project site.Project Effects The SCAQMD develops rules and regulations, establishes permitting requirements for stationary sources, inspects emissions sources, and enforces such measures through educational programsor fines, when necessary. It is directly responsible for reducing emissions from stationary (areaand point), mobile, and indirect sources and has prepared an Air Quality Management Plan(AQMP) that establishes a program of rules and regulations directed at attaining the National Ambient Air Quality Standards (NAAQS) and California Ambient Air Quality Standards (CAAQS). 4-12 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
The 2022 AQMP was adopted on December 2, 2022, by the SCAQMD Governing Board. The 2022 AQMP evaluates integrated strategies and measures to meet the following NAAQS (SCAQMD 2022):
• 8-hour Os target of 80 parts per billion (ppb) by 2024, 75 ppb by 2032, 70 ppb by 2038; Annual PM2.5 target of 12 micrograms per cubic meter [pg/m3] by 2025; 1-hour Os target of 120 ppb by 2023; and
24-hour PM2.5 target of 35 pg/m3 by 2023.

Pursuant to the SCAQMD's CEQAAir Quality Handbook, a project would be inconsistent with the AQMP if it would (SCAQMD 1993):

Create an increase in the frequency or severity of air quality violations; cause or contributeto new violations; delay attainment of air quality standards; or Exceed the assumptions of the AQMP.

For the first criterion, the main purpose of an AQMP is to bring an area into compliance with the requirements of federal and State air quality standards. For a project to be consistent with the AQMP, the pollutants emitted from the project should not exceed the SCAQMD CEQA air quality significance thresholds. A project with daily emission rates below the SCAQMD's established airquality significance thresholds (shown above in Table 3) would have a less than significant effect on regional air quality. As shown in response to Threshold 5.2(b) below, pollutant emissions from the Project would be less than the SCAQMD thresholds; therefore, the Project meets the first criterion.

With respect to the second criterion, the Project was evaluated to determine whether it would exceed the assumptions in the 2022 AQMP. The 2022 AQMP is a regional and multi-agency effortamong the SCAQMD, CARB, Southern California Association of Governments (SCAG), and theUSEPA. The purpose of the 2022 AQMP is to set forth a comprehensive program to promotereductions in criteria pollutants, greenhouse gases, and toxic risk and improve efficiencies in energy use, transportation, and goods movement. The 2022 AQMP incorporates the latestscientific and technical information and planning assumptions, including the 2020-2045 RegionalTransportation Plan/Sustainable Communities Strategy; updated emission inventory methods for various source categories; and SCAG's latest growth forecasts (SCAQMD 2022). The 2022AQMP includes strategies and measures necessary to meet the NAAQS. The AQMP is based on projections of energy usage and vehicle trips from land uses within the SoCAB.

The Project site has a General Plan land use designation of S and zoning designation of OS. The Project would develop a well, pipeline, and related improvements that the City has determined would be consistent with the OS land use designation and zoning classification. Moreover, the Project would not directly result in population growth or development, or new land uses that have not been anticipated in the 2022 AQMP and the Project does not involve land uses that wouldincrease the frequency or severity of air quality violations; cause or contribute to new violations; or delay attainment of air quality standards or exceed the assumptions of the AQMP. Therefore, the Project would not conflict with or obstruct implementation of the AQMP. The Project would also involve development of local water supplies which is less energy and pollution intensive thanimporting water.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
4-13 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
b) Would the project result in a cumulatively considerable net increase of any criteria pollutant for which the project region is in non-attainment under an applicable federal or state ambient air quality standard.

Less Than Significant Impact. The SCAQMD has adopted significance thresholds to assess theregional impact of air pollutant emissions in the SoCAB. Table 5, SCAQMD Regional EmissionsSignificance Thresholds, summarizes the SCAQMD's mass emissions thresholds, which arepresented for both short-term construction and long-term operational emissions. A project withemissions rates below these thresholds is considered to have a less than significant impact on airquality.

TABLE 5

SCAQMD REGIONAL POLLUTANT SIGNIFICANCE THRESHOLDS
(LBS/DAY)
Mass Daily Thresholds (Ibs/day)
Pollutant
voc
Construction
75 Operation
55 NOx
co
100
550
55 550
PM10
PM2.5
150
55 150
55 SOx
Lead
150
3 150
3 Ibs/day: pounds per day; VOC: volatile organic compound; NOx: nitrogen oxides;CO; carbon monoxide; PM10: respirable particulate matter 10 microns or less indiameter; PM2.5: fine particulate matter 2.5 microns or less in diameter; SOx:sulfur oxides.Source:SCAQMD2019 Regional Construction Impacts
The SCAQMD has established methodologies to quantify air pollutant emissions associated with construction activities, such as air pollutant emissions generated by operation of on-siteconstruction equipment; fugitive dust emissions related to trenching and earthwork activities; and mobile (tailpipe) emissions from construction worker vehicles and haul/delivery truck trips.Emissions would vary from day to day, depending on the level of activity; the specific type of construction activity occurring; and, for fugitive dust, prevailing weather conditions.

A construction-period mass emissions inventory was compiled for the Project based on anestimate of construction equipment as well as scheduling and Project phasing assumptions thatwere developed by Psomas in consultation with the City. More specifically, the mass emissions analysis considers the following:

Combustion emissions from operating on-site stationary and mobile constructionequipment; Fugitive dust emissions from demolition, site preparation, and grading phases; andMobile-source combustion emissions and fugitive dust from worker commute and truck travel.
4-14 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Emissions were calculated using the California Emissions Estimator Model Version 2022.1.1.17(CalEEMod) emissions inventory model (CAPCOA 2022). CalEEMod is a computer programaccepted by the SCAQMD that can be used to estimate anticipated emissions associated with land development projects in California. CalEEMod has separate databases for specific counties and airdistricts, and the Los Angeles County database was used for the Project. Consistent with the requirements of SCAQMD Rule 403 (RR AQ-1), watering for dust control is included in the emissions calculations.The regional emissions thresholds that are presented above within Table 5 are based on the rate of emissions (i.e., pounds of pollutants emitted per day). Therefore, the quantity, duration, and theintensity of construction activities are important in ensuring analysis ofworst-case (i.e., maximum daily emissions) scenarios. Project activities (e.g., demolition, grading, building construction) are identified by start date and duration, as described in Table 1. Each activity has associated off-road equipment (e.g., backhoes, loaders, cranes) and on-road vehicles (e.g., haul trucks, concretetrucks, worker commute vehicles). Detailed construction assumptions and CalEEMod inputs and outputs can be found in Appendix A.Maximum daily construction emissions during the peak workday are shown in Table 6, EstimatedMaximum Daily Construction Emissions. If construction is delayed or occurs over a longer timeperiod, emissions could be reduced because of (1) a more modern and cleaner-burningconstruction equipment fleet mix and/or (2) a less intensive buildout schedule (i.e., fewer daily emissions occurring over a longer time interval). As shown, all criteria pollutant emissions from Project construction would be less than their respective thresholds.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.

TABLE 6

ESTIMATED MAXIMUM DAILY CONSTRUCTION EMISSIONS
(LBS/DAY)
Construction Year voc NOx co SOx PM10 PM2.5
2024
3 31 47 <1
2 1
2025
2 14 23 <1 1 1
Maximum Construction Emissions
3 31 47 <1
2 1
SCAQMD Daily Thresholds 75 100 550 150 150 55
Exceeds SCAQMD Thresholds? No No No No No No
Ibs/day: pounds per day; VOC: volatile organic compound(s); NOx: nitrogen oxides; CO: carbon monoxide; SOx: sulfur oxides;PM10: respirableparticulate matter with a diameter of 10 microns or less; PM2.5: fine particulate matter with a diameter of 2.5microns or less; SCAQMD: South Coast Air Quality Management District.Source: SCAQMD 2015 (thresholds). Emissions calculated by Psomas using CalEEMod 2022.1.1.17 Localized Construction Impacts
In addition to the mass daily emissions thresholds established by the SCAQMD, short-term localimpacts to nearby sensitive receptors from on-site emissions of N02, CO, PM10, and PM2.5 are examined based on SCAQMD's localized significance threshold (LST) methodology. To assess local air quality impacts for development projects without complex dispersion modeling, the SCAQMD has developed screening (lookup) tables that assist lead agencies in evaluatingimpacts. The LST method was developed to provide a conservative estimate of the level ofproject-generated air pollutants that have the potential to exceed the NAAQS or CAAQS, whichcould consequently result in adverse health impacts. Exceedance of the LST does not describe 4-15 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
the prevalence or magnitude of health effects, but rather assesses the potential for a project-related health effect to occur. The LST method cannot provide an estimate of health effects related to criteria pollutants or ozone. Reactive organic gases and NOx are pollutants thatcontribute to the formation of ozone, otherwise known as ozone precursors. It would be too speculative to determine how an individual project could affect the formation of ozone, and how itcould affect the health for a specific receptor because ozone does not fully form within theproximity of a Project site, and the formation of ozone is affected by solar irradiance, meteorological conditions, presence of ozone precursors from other sources, and other factors.

As such, modeling of ozone concentrations is conducted on the "macro" scale of an air basin for all pollutant sources within the basin, and not for an individual project.The LST method is recommended to be limited to projects that are five acres or less. For the purposes of an LST analysis, the SCAQMD considers receptors where it is possible that anindividual could remain for 1 hour for N02 and CO exposure and 24 hours for PM10 and PM2.5 exposure. The emissions limits in the lookup tables are based on the SCAQMD's Ambient Air Quality Standards (SCAQMD 2022). The closest receptors that may remain for 1 hour areresidential uses located approximately 195 feet to the east of the Project's boundaries.

Table 7, Construction-Phase Localized Significance Threshold Emissions, shows the maximumdaily on-site emissions for construction activities compared with the SCAQMD LST screeningcriteria. The Project's maximum daily on-site emissions would occur during the demolition phase (for NOx and CO), and during the grading/excavation phase (for PM10 and PM2.5). As shown in Table 7, localized emissions for all criteria pollutants would be less than their respective screening criteria. Therefore, localized air quality impacts at receptors proximate to construction activities would be exposed to less than significant air quality impacts.

TABLE 7

CONSTRUCTION-PHASE

LOCALIZED SIGNIFICANCE THRESHOLD EMISSIONS
Emissions and Thresholds
Emissions (Ibs/day)
NOx co PM10 PM2.5
Project maximum daily on-site emissions 16 22 1 1
Localized Significance Threshold screeningcriteria* 71 858 14 5Exceed screening criteria? No No No NoIbs/day: pounds per day; NOx: nitrogen oxides; CO: carbon monoxide; PM10: respirable particulate matter 10 microns orless in diameter; PM2.5: fine particulate matter 2.5 microns or less in diameter.Note: Data is for SCAQMD Source Receptor Area 8, West San Gabriel Valley* NOx, CO, PM10 and PM2.5 thresholds are based on a distance of 60 meters (197 feet) of the Project site.Source: SCAQMD 2009 (thresholds); see Appendix A for CalEEMod model outputs.

Toxic Air Contaminants Impacts
Construction activities would result in short-term, Project-generated emissions of diesel particulate matter (DPM) from the exhaust of off-road, heavy-duty diesel equipment used for sitepreparation (e.g., demolition, excavation, and grading); paving; building construction; and othermiscellaneous activities. CARB identified DPM as a Toxic Air Contaminant (TAC) in 1998. The dose to which receptors are exposed is the primary factor used to determine health risk. Dose isa function of the concentration of a substance or substances in the environment and the durationof exposure to the substance. Thus, the risks estimated for a maximally exposed individual are higher if a fixed exposure occurs over a longer time period. According to the California EPA's 4-16 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Office of Environmental Health Hazard Assessment, health risk assessments—which determine the exposure of sensitive receptors to TAG emissions—should be based on a 30-year exposure period; however, such assessments should be limited to the period/duration of activities associated with the Project.There would be relatively few pieces of off-road, heavy-duty diesel equipment in operation during Project construction, and the total construction period would be relatively short when compared to a 30-year exposure period. Combined with the highly dispersive properties of DPM and additional reductions in particulate emissions from newer construction equipment, as required by USEPA and CARB regulations as well as the relatively large distance between the Project site and the nearest sensitive land uses, construction emissions ofTACs would not expose sensitivereceptors to substantial emissions of TACs. Therefore, the Project would have a less thansignificant impacted related to TACs, and no mitigation is required.Long-Term Operational ImpactsOnce the Project is built, the primary usage of energy would be related to electricity consumed for the well operations. Sources of new energy demand resulting from Project implementation include the pump at the proposed Explorer Well. The Project is estimated to use approximately

1.4 million kilowatt hours per year. Electricity use would not result in direct air quality related emissions but would result in greenhouse gas emissions. Also, there would be a minor increase in trips to the Project site for inspection and maintenance of the proposed well and ancillary facilities. With implementation of the Project, there would be one monitoring and maintenance round trip per day, including Saturdays, for an increase in six round trips per week compared to existing trips. Emissions associated with the operations phase of the Project would be negligiblegiven the nominal increase in trips. Based on the results of the CalEEMod modeling found in Appendix A of this IS/MND, the Project's operations phase would result in less than 1 pound per day of all analyzed criteria pollutants, which is substantially less than the SCAQMD's operationsphase significance thresholds. Therefore, there would be less than significant operationalimpacts, and no mitigation is required.Cumulative Basis The SCAQMD in their White Paper on Regulatory Options for Addressing Cumulative Impacts from Air Pollution Emissions (presented to the Board on September 5, 2003), identifies that impacts that are less than significant on a Project level are also considered to be less than significant on a cumulative basis. The AQMD uses the same significance thresholds forproject-specific and cumulative impacts for all environmental topics analyzed in an Environmental Assessment or EIR, except for the Hazard Index for TAG emissions (SCAQMD 2003). Any projects that are found to result in less than significant impacts on a project level are not considered to be cumulatively considerable and consequently would not result in a considerablecontribution to cumulative impacts. Using this rationale, since the Project impacts were identifiedas less than significant, the Project's contribution to cumulative impacts would also be less than significant.Overall, the Project would have a less than significant impact related to this threshold, and nomitigation is required. 4-17 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
c) Would the project expose sensitive receptors to substantial pollutant concentrations?
Less Than Significant Impact. As described in Threshold 4.3(b), the Project would not result in any significant TAC air pollution impacts, and construction criteria pollutant emissions would be less than the conservative LSTs. Therefore, Project construction would not expose any nearby sensitive receptors to substantial pollutant concentrations.A CO hotspot is an area of elevated CO concentrations that is caused by severe vehicle congestion on major roadways, typically near intersections. If a project substantially increasesaverage delay at signalized intersections that are operating at Level of Service (LOS) E or F or causes an intersection that would operate at LOS D or better without the project to operate at LOS E or F with the project, there is a potential for a CO hotspot.

The Project would generate vehicle traffic from additional maintenance trips to the Project sitethat would not have occurred without implementation of the Project. Due to the low quantity oftrips (i.e., one or two trips per day), and that vehicles are already nearby for maintenance of other existing facilities, this volume and duration of Project-related vehicle trips would not have thepotential to substantially add to the average LOS at nearby intersections and consequently wouldnot contribute to the potential for the formation of a CO hotspot.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
d) Would the project result in other emissions (such as those leading to odors adversely affecting a substantial number of people?
Less Than Significant Impact. According to the SCAQMD's CEQAAir Quality Handbook, land uses associated with odor complaints typically include agricultural uses, wastewater treatmentplants, food processing plants, chemical plants, composting, refineries, landfills, dairies, and fiberglass molding (SCAQMD 1993). The Project does not propose any of these land uses andwould not otherwise produce objectionable long-term operational odors. Additionally, the Explorer Well would be enclosed within a building and would not result in any airborne emissions or anysubstances that have odors that rise to a level of a public nuisance.

Odors would be generated from short-term construction equipment and activities such as diesel exhaust emissions from construction equipment and paving activities. There may be situations where construction activity odors would have an olfactory presence, but these odors would not be unfamiliar or necessarily objectionable. Furthermore, the odors would be temporary and would dissipate rapidly from the source with an increase in distance. All Project-related odors areconstruction related and short term in nature and would not rise to the level of a public nuisance; therefore, the Project would not result in odors or other emissions adversely affecting a substantial number of people.

As such, the Project would have a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to air quality were identified; therefore, no mitigation measuresare required. 4-18 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.4 BIOLOGICAL RESOURCES
Less Than
Potentially Significant Less Than
Significant With Significant No
Impact Mitigation Impact Impact
Would the project:a) Have a substantial adverse effect, either directly or through habitat modification, on any species identifiedas a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by theCalifornia Department of Fish and Wildlife or U.S. Fishand Wildlife Service? b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local orregional plans, policies, regulations, or by the California Department of Fish and Wildlife or U.S. Fish and
Wildlife Service?
c) Have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the Clean WaterAct (including, but not limited to, marsh, vernal pool,coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with
established native resident or migratory wildlifecorridors, or impede the use of native wildlife nurserysites? e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
f) Conflict with the provisions of an adopted Habitat
Conservation Plan, Natural Community Conservation
Plan, or other approved local, regional, or state habitat conservation plan?
D s D DD a a s
D a a ^DD
D
sDa
asa
DDs

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to biological resources.

Impact Discussion
a) Would the project have a substantial adverse effect, either directly or through habitat modification, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service? Less Than Significant With Mitigation. A general biological resources survey and habitat assessment was conducted on the Project site by Psomas Senior Biologist Marc Blain on July28, 2023. All areas within the Project's proposed disturbance limits were assessed to documentexisting biological resources and determine suitability to support other resources including specialstatus plant and wildlife species. 4-19 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
As depicted in Exhibit 2b, the Project site is located within a formerly paved parking lot and is partially located within currently paved roadways (Explorer Road and Karl Johnson Parkway). TheProject site lacks vegetation other than scattered non-native weeds and minimal overhanging canopy from adjacent vegetated natural areas. A review of all special status species potentially occurring in the Project region, as reported in the California Natural Diversity Data Base, indicates there is no suitable habitat to support special status plant or wildlife species within the Project site (Appendix E; Special Status Species Potentially Occurring in the Region). There is limitedpotential for special status bird species to fly over the Project site, but they would not be expected to utilize the Project site for foraging or breeding or any other activity that would result in them using or inhabiting the Project site for extended time.One special status wildlife species, the coastal whiptail (Aspidoscelis tigris stejnegeri), a Californiaspecies of special concern, may potentially occuroff-sitewithin adjacent upland vegetated naturalareas. This reptile may occur but would likely be limited in numbers due to prior disturbance of the Project site and fragmented suitable habitat due to paved roadways and parking lots, residential development, and infrastructure facilities in the Project vicinity. Due to the Project site'sproximity to potentially occupied habitat, coastal whiptail individuals have potential to be harmed during Project activities. Due to the status as a species of special concern, these impacts would be considered significant unless mitigated. Potential impacts on coastal whiptail would be reduced to a less than significant level with implementation of MM BIO-1, which requires the installation of exclusionary fencing between adjacent habitat and Project work areas.The Project would result in indirect impacts resulting from increases in noise level, dust, nightlighting during both construction and operation. However, due to the existing levels of indirect disturbances in the area from surrounding roadways, pedestrian trails, equestrian trails, water infrastructure facilities, JPL, residential communities, the Project's impact would be considerednegligible and unlikely to have a measurable effect on special status species. Therefore, theindirect impacts of the Project would be considered less than significant.

With implementation of
to this threshold.

BIO-1, the Project would have a less than significant impact related b) Would the project have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
No Impact. As described above, the Project site surface is paved and was formerly a parkingarea. The site lacks vegetation other than scattered individual weeds and minimal overhanging canopy from adjacent vegetated natural areas (See Exhibit 2b). Due to the lack of vegetation on the site, no riparian habitat or other sensitive natural community would be impacted by the Project.Although trimming of a few branches overhanging the site may occur as needed, these individual plants do not constitute a community and disturbance would be extremely limited and would nothave a measurable effect on any habitat or community. Therefore, the Project would have no impact related to this threshold, and no mitigation is required. c) Would the project have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling,hydrological interruption, or other means? No Impact. No riparian habitat, wetlands, or watercourses occur within the Project site orimmediately adjacent areas. The nearest natural jurisdictional drainage with riparian habitat, the 4-20 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Arroyo Seco channel, is located approximately 500 feet to the west. The nearest potentially protected riparian habitat is located on the margin of an infiltration basin approximately 200 feetnorthwest of the Project well site and further from the pipeline portions of the site. Therefore, the Project would have no impact related to this threshold, and no mitigation is required. d) Would the project interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites? Less Than Significant With Mitigation. The Project site is not expected to support regional wildlife movement due to the Project Site's limited size and location outside of recognized regionalwildlife movement corridors. The Arroyo Seco and Hahamongna Watershed Park do provide for local wildlife movement, especially for urban-adapted wildlife such as coyotes, foxes, raccoons, and opossums through the area. However, considering the Project site is a former parking lot,lacks vegetation, and is located outside of recognized regional wildlife movement corridors, itdoes not support regional wildlife movement. As a result, the Project site would not be considereda vital component to the function of this area for regional wildlife movement. There may be indirecteffects on wildlife movement (e.g., increased noise or dust), but these would be considerednegligible and unlikely to affect existing wildlife movement in the watershed.

Nesting birds are protected under the provisions of the Migratory Bird Treaty Act and CaliforniaFish and Game Code. The U.S. Fish and Wildlife Service periodically publishes the list ofmigratory birds covered by the provisions of this statute, but essentially all naturally occurring bird species in North America would be migratory and are included on the list. The Project site providesvery limited potential for nesting birds; however, adjacent areas support potentially suitable nesting habitat for migratory birds, which could be adversely impacted indirectly by construction of the Project. The loss of an active nest may be considered potentially significant; therefore,MM BIO-2 would be implemented requiring that all construction activities occur outside the birdnesting season. If construction must occur between February 1 and September 15, which is within the bird nesting season, a pre-construction survey for nesting birds (including raptors), is required and any active nests must be protected to reduce potentially significant impacts to a level of less than significant.

With implementation of MM BIO-2, the Project would result in a less than significant impact related to this threshold.
e) Would the project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance? Less Than Significant Impact. The City of Pasadena tree protection ordinance, codified as Chapter 8.52 of the City's Code of Ordinances, provides protections for all public trees and it is aviolation to prune, remove, injure, or plant a public tree without a City permit. Disturbance in the root zone of a protected tree may be considered a potential injury. A survey of the Project site was conducted by Psomas, as noted above, which determined that there are no trees within the Project site. However, regulated trees are present within areas adjacent to the Project site. The root zone of a tree under normal conditions is typically considered to match the drip line. Althoughunlikely, it is possible that trenching activities for new pipeline construction that would occur on the roadway between theArroyo Well and the Ventura Well (Karl Johnson Roadway) could injuretree roots.Therefore, trees regulated by the City of Pasadena tree ordinance may be impacted by trenching and/or other Project activities. The project will comply with the City ordinance and will obtainauthorization from the City Manager prior to any potential impact on a regulated tree. Therefore, 4-21 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
such impacts would not result in a conflict with a local ordinance protecting biological resources, and no mitigation is required.f) Would the project conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?
No Impact. There is no adopted Habitat Conservation Plan (HCP); Natural CommunityConservation Plan; or other approved State, regional, or local HCP that applies to the Project site.

Therefore, the Project would result in no impact related to this threshold, and no mitigation is required.Mitigation Measures
BIO-1 Prior to the start of construction of the Explorer Well portion of the Project, an exclusionary fence shall be installed to prevent coastal whiptail from entering the work area. The fence shall be installed along the eastern edge of the project disturbance limits at the Explorer Well, which is located at the toe of the vegetatedslope. The exclusionary fencing shall consist of silt fencing, buried six inches deep where feasible and installed with no gaps in the fencing. Fencing shall be installed under the supervision of a qualified Biologist to ensure that wildlife are notimpacted during installation of the fence. Exclusionary fencing shall be maintained throughout construction of the Explorer Well and shall be removed uponcompletion of the Explorer Well construction activities.

MM BIO-2 If feasible, project construction shall be conducted between September 16 and January 31, which is outside the bird nesting season. Construction conducted within this period shall be considered in compliance with the conditions set forth inthe Migratory Bird Treaty Act (MBTA) and California Fish and Game Code with methods approved by the U.S. Fish and Wildlife Sen/ice (USFWS) and CaliforniaDepartment of Fish and Wildlife (CDFW) to protect active bird and raptor nests. If the nature of the proposed construction activities requires that work be conductedduring the breeding season for nesting birds (March 15-September 15) or nesting raptors (February 1-June 30), to avoid direct impacts on active nests, apre-construction survey shall be conducted by a qualified Biologist for nesting birdsand/or raptors within 3 days prior to any construction or disturbance activities (i.e., within 300 feet for nesting birds and within 500 feet for nesting raptors). If the Biologist does not find any active nests within or immediately adjacent to theimpact area, the construction work shall be allowed to proceed. If a lapse of more than three days occurs between outdoor disturbance activities, the nesting birdsurvey will need to be repeated as nesting activities may potentially occur in that time frame. Results of the surveys will be provided to the City and to CDFW.

If the Biologist finds an active nest within or immediately adjacent to the construction area and determines that the nest may be impacted or breedingactivities substantially disrupted, the Biologist shall delineate an appropriate buffer zone (at a minimum of 25 feet) around the nest depending on the sensitivity of the species and the nature of the construction activity. Any nest found during survey efforts shall be mapped on the construction plans. The active nest shall be protected until nesting activity has ended. To protect any nest site, the followingrestrictions to construction activities shall be required until nests are no longer active, as determined by a qualified Biologist: (1) clearing limits shall beestablished within a buffer around any occupied nest (the buffer shall be 25-100 4-22 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
feet for nesting birds and 300-500 feet for nesting raptors), unless otherwisedetermined by a qualified Biologist and (2) access and surveying shall be restricted within the buffer of any occupied nest, unless otherwise determined by a qualified Biologist. Encroachment into the buffer area around a known nest shall only be allowed if the Biologist determines that the proposed activity would not disturb the nest occupants. Construction can proceed when the qualified Biologist has determined that fledglings have left the nest or the nest has failed. 4-23 Environmental Assessment
Explorer Well Project
Initial Study/M/tigated Negative Declaration

4.5 CULTURAJLRESOURCES
Less Than
Potentially Significant Less Than
Significant with Significant No
Impact Mitigation Impact Impact
Would the project:a) Cause a substantial adverse change in the significance of a historical resource pursuant to § 15064.5?
b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to § 15064.5?
c) Disturb any human remains, including those interred
outside of dedicated cemeteries?
aa
D
D
D
aD
s
sD
D

IMPACT ANALYSIS
Regulatory Requirements
RR CUL-1 If human remains are encountered during excavation activities, all work is required to halt in the immediate vicinity of the discovery and the County Coroner must be notified (California Public Resources Code §5097.98). The Coroner is required to determine whether the remains are of forensic interest. If the Coroner, with the aidof an archaeologist, determines that the remains are prehistoric, they are required to contact the Native American Heritage Commission (NAHC). The NAHC is responsible for designating the most likely descendant (MLD), who is responsible for the ultimate disposition of the remains, as required by Section 7050.5 of the California Health and Safety Code. The MLD is required to make their recommendation within 48 hours of being granted access to the site. The MLD's recommendation is required to be followed, if determined by the landowner to be feasible, and may include scientific removal and non-destructive analysis of the human remains and any items associated with Native American burials (California Health and Safety Code §7050.5). If the landowner rejects the MLD's recommendations, at a minimum the landowner is required to rebury the remains with appropriate dignity on the property in a location that will not be subject tofurther subsurface disturbance (California Public Resources Code §5097.98).

Impact Discussion
a) Would the project cause a substantial adverse change in the significance of a historical resource pursuant to § 15064.5?
No Impact. A cultural resources records search and literature review for the Project was conducted at the South-Central Coastal Information Center (SCCIC) in July 2023. The records search included a 1/2-mile radius around the Project site and was conducted by Psomas cultural resource staff. The purpose of the SCCIC search was to identify precontact2 or historicarchaeological sites or historic buildings and structures previously recorded within and around theProject site. The results revealed that 20 cultural resource studies have been conducted within the ^-mile radius of the Project site. Of the 20 studies, one study (LA-6948) from 2002 covered (e.g., previously studied) a portion of the Project site. The remaining studies range in date from 1965 to 2012 and did not overlap with the Project site. The types of studies identified from the literature review include archaeological resource surveys and assessments, and literature and2 Precontact refers to a period of time before contact of an indigenous people with European culture. 4-24 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
background research for the region. These studies are evidence of the cultural resource sensitivityof the region, including the Project site. However, even though the region is sensitive for culturalresources (Walker 1951), the SCCIC records search identified no previously recorded culturalresources within or adjacent to the Project site.

The California Historic Resources Information System (CHRIS) records indicate that the Angeles National Forest (Resource P-19-186535) is a registered California Historical Landmark; however, the Project is not anticipated to impact this resource.

The cultural studies for the Arroyo Seco Canyon Project identified that there are eight builtenvironment resources near the Project site (City of Pasadena 2020a, 2020b). These resources include the Jet Propulsion Laboratory campus, the registered National Historic Landmark SpaceFlight Operations Facility and the National Register of Historic Places (NRhlP) eligible Space Simulator, which are both within the Jet Propulsion Laboratory campus; the United States Department of Agriculture (USDA) Forest Service Oak Grove administrative site; two individualbuildings within the Arroyo Seco Ranger Station administration site; a USDA Forest Service Road; and the California Register of Historical Resources (CRHR) listed single-family property built in 1924 known as the Buffum House. TheArroyo Seco Canyon Project's EIR also determined that there were an additional three built resources near the Project site, including the Behner WaterTreatment Plant, Bridge No. 2, and Bridge No. 3, that were found to be eligible for NRHP, CRHR, and local designation. The Project would not affect any of the aforementioned cultural or historical resources.

Given that there are no known historical resources located on or adjacent to the Project site, thatare listed or eligible for listing under the NRHP or the CRHR, the Project would not result inimpacts related to this threshold, and no mitigation is required. b) Would the project cause a substantial adverse change in the significance of an archaeological resource pursuant to § 15064.5?
Less Than Significant With Mitigation. As discussed above, there is one documented culturalresource study that covered a portion of Project site, but no cultural resources have been recorded within or adjacent to the Project site itself.

However, because the region is sensitive for precontact cultural resources (Walker 1951), it islikely that indigenous Californians traversed the Project site and surrounding area in precontact times. Nevertheless, the surrounding floodplain has likely washed away archaeological resourcesor buried them by alluvial and colluvial processes, thus impacting the integrity of thearchaeological resource(s). While unlikely, buried intact cultural resources with integrity couldexist on the Project site in previously undisturbed soils that could be damaged by grounddisturbing activities for Project construction. hlowever, much of the Project's grading, excavation, trenching, and construction of building foundations would involve disturbance of previously disturbed areas, which reduces the likelihood of encountering cultural resources. Nonetheless, if intact archaeological resources were to be encountered, that would represent a significant impact to an archaeological resource.To avoid impacts to archaeological resources potentially discovered during Project grounddisturbance activities, MM CUL-1 would be implemented, which requires that a qualifiedarchaeologist be retained for on-call services in the event of the discovery of archaeological resources during ground disturbing activities. Any discovered resources would be evaluated for significance by a qualified archaeologist and a mitigation plan would be developed in consultation with the City and the local Native American community (if resources are precontact in origin). With 4-25 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
implementation of MM CUL-1, the Project would have a less than significant impact related to this threshold.
c) Would the project disturb any human remains, including those interred outside of formal cemeteries?
Less Than Significant Impact. While human remains from the Precontact period have been found elsewhere in the City of Pasadena, the SCCIC records search did not identify documented evidence of any known human remains on or near the Project site. In the unlikely event of an unanticipated encounter with human remains, the California Health and Safety Code and the California Public Resources Code require that any activity near a potential find be halted, and the Los Angeles County Coroner be notified, as described in RR CUL-1. With implementation ofRR CUL-1, the Project would result in a less than significant impact related to this threshold, andno mitigation is required.

MITIGATION MEASURES
MM CUL-1 Prior to commencement of earthmoving activities, the City shall retain a qualified Archaeologist meeting the Secretary of the Interior's Professional QualificationStandards for Archaeology. The Archaeologist shall be present at the pre-gradeconference; shall establish procedures for archaeological resource surveillance;and shall establish, in cooperation with the Contractor, procedures for temporarily halting or redirecting work to permit the sampling, identification, and evaluation of the artifacts, as appropriate. At a minimum, in the event archaeological resources are exposed during construction activities, all construction work occurring within 100 feet of the find shall immediately stop until a qualified archaeologist can evaluate the significance of the find and determine whether additional study iswarranted. The Archaeologist shall first determine whether it is a "uniquearchaeological resource" pursuant to the California Environmental Quality Act(CEQA, i.e., Section 21083.2[g] of the California Public Resources Code) or a"historical resource" pursuant to Section 15064.5(a) of the State CEQA Guidelines.

If the archaeological resource is determined to be a "unique archaeological resource" or a "historical resource", the Archaeologist shall formulate a mitigationplan in consultation with the City of Pasadena that satisfies the requirements of theabove-referenced sections. The Archaeologist shall prepare a report of the resultsof any study prepared as part of a testing or mitigation plan, following guidelinesof the California Office of Historic Preservation, and they shall record the site andsubmit the recordation form to the City of Pasadena and the California HistoricResources Information System (CHRIS) at the South-Central Coastal Information Center (SCCIC) at California State University, Fullerton. Work may proceed inother areas of the site, subject to the direction of the Archaeologist. 4-26 Environmental Assessment
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Initial Study/Mitigated Negative Declaration

4.6 ENERGY Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:a) Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction oroperation? a D s a
b) Conflict with or obstruct a state or local plan for
renewable energy or energy efficiency? D a

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to energy.

Impact Discussion
a) Would the project result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation?
Less Than Significant Impact. Related to existing demands for energy, the existing wells,booster stations and treatment facility that are a part of the MHTS currently use energy for their operation. There is an existing Southern California Edison high-voltage overhead power line thatcrosses the Arroyo Seco in an east-west direction to the north of the Project. The Project site is within the PWP service area and there are PWP overhead power lines along North WindsorAvenue adjacent to the MHWTP, along North Arroyo Boulevard/Gabrielino Trail for service to the Behner Water Treatment Plant and other facilities to the north, and along other paths to service other facilities in the extended Project area.

Project construction would require the use of construction equipment for well drilling, vehicles of construction workers and vendors traveling to and from the Project site, on-road haul trucks for the export of materials from site clearing and the export of sediment from excavation, and semi-trailer trucks for the delivery of equipment and materials.Off-road construction equipment use was calculated from the equipment data (vehicle types,hours per day, horsepower, load factor) provided in the CalEEMod construction output files thatare included in Appendix A. The total horsepower hours for construction equipment used for theProject was then multiplied by fuel usage rates to obtain the total fuel usage for off-roadequipment.Fuel consumption from construction worker, vendor, and delivery/haul trucks was calculated using the trip rates and distances provided in the CalEEMod construction output files. Total vehicle milestraveled (VMT) was then calculated for each type of construction-related trip and divided by thefuel consumption factor from CARB's Emission FACtors (EMFAC) 2021 model. EMFAC providesthe total annual VMT and fuel consumed for each vehicle type. Construction vendor anddelivery/haul trucks were assumed to be heavy-duty diesel trucks. As shown in Table 8, Energy 4-27 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Use During Construction, the Project is estimated to consume a total of 12,657 gallons of gasolineand 25,857 gallons ofdiesel fuel during construction.

TABLE 8

ENERGY USE DURING CONSTRUCTION
Source
Gasoline Fuel
(gallons)
Diesel Fuel -
(gallons)
Off-road Construction EquipmentWorker commute
4,969
7,659
25,486
19 VendorsOn-road haul and delivery
Total
28 0
12,657
0 352
25,857
Sources: Psomas 2020 based on data from CalEEMod (Appendix A), Offroad, and EMFAC2021(Appendix B).

Fuel energy consumed during construction would be temporary in nature and would not represent a significant demand on energy resources. Furthermore, there are no unusual Projectcharacteristics that would necessitate the use of construction equipment that would be lessenergy-efficient than comparable equipment at construction sites in other parts of the State.

Therefore, construction of the Project would not result in inefficient, wasteful, or unnecessary fuel consumption.Sources of new energy demand resulting from Project implementation include the pump at the proposed Explorer Well. The Project is estimated to use approximately 1.4 million kilowatt hoursper year. This new demand for energy is not enough to require the development of new energy sources. No demand for natural gas would be created by the Project. Energy used in the operationof the Project allows for improved resiliency of the water system and reliability of PWP's local water supply, thereby lessening dependence on more energy-intensive imported water.

Also, a minimal amount (1-2 trips/day) of maintenance and inspection activities would generatevehicle trips that would utilize fossil fuels.

Due to the relatively small amount of energy used for operation and because the Project haspublic utility through the treatment of groundwater, the Project's energy use would not beconsidered wasteful or inefficient.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.b) Would the project conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
Less Than Significant Impact. Operation of the Explorer Well's pump would require use of electricity. Electricity would be provided by tying into existing PWP infrastructure. Specifically,there are existing PWP overhead power lines and power poles in and near the site that would be used for the Project. Therefore, although the Project would result in a slight increase in overall electrical usage, no new major infrastructure (i.e., new energy sources) would be required tosupport the Project, and any new electrical connections would be constructed in accordance with the City's Building Code.

The City's Energy Element of the 1983 General Plan was replaced by the City's Open Space andConservation Element in 2012 (City of Pasadena 2012). The purpose of the Open Space and 4-28 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Conservation Element is to develop policies that promote the conservation of energy, air, water,and natural resources to enhance the overall quality of life in Pasadena. In terms of energy, theCity seeks to improve energy conservation, expand renewable energy production, and promote sustainability. As discussed in the "Existing Utility Conditions and Urban Planning" Section of this Element, the City has goals of increasing conservation, efficiency, and sustainability. The Project is consistent with these goals since the Project would extract and clean local groundwater, whichcan help the City to have less dependence on imported water Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to energy were identified; therefore, no mitigation measures arerequired. 4-29 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.7 GEOLOGY AND SOILS Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:a) Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or deathinvolving:
i) Rupture of a known earthquake fault, as delineated
on the most recent Alquist-Priolo Earthquake Fault
Zoning Map issued by the State Geologist for the
area or based on other substantial evidence of aknown fault? Refer to Division of Mines andGeology Special Publication 42. ii) Strong seismic ground shaking?iii) Seismic-related ground failure, including liquefaction?
iv) Landslides?
b) Result in substantial soil erosion or the loss of topsail?c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project,
and potentially result in onsite or offsite landslide, lateral spreading, subsidence, liquefaction, or collapse?
d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating
substantial direct or indirect risks to life or property? e) Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposalsystems where sewers are not available for the disposal of waste water?
f) Directly or indirectly destroy a unique paleontological resource or site or unique geological feature?
D
DDDaDa
DD
D s D
DDDaDa
Ds
sssss^
Da
DDnDDD
sa

IMPACT ANALYSIS
Regulatory RequirementsRR GEO-1 Grading, excavation, and construction is required to comply with the City's Building Code (Title 14 of the Pasadena Municipal Code, which incorporates the California Building Code), as they relate to site preparation and construction; alteration;moving; demolition; repair; use and occupancy of buildings; structures and building service equipment within the City. The California Building Code requires the preparation of engineering geologic reports, supplemental ground-responsereports, and/or geotechnical reports for all new construction; new structures on existing sites; and alterations to existing buildings. It also includes seismic designcriteria and requirements for use in the structural design of buildings (i.e., basedon seismic hazard maps and the seismic design category) and specifies building components that require special seismic certification.
4-30 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
Impact Discussion
a) Would the project expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:i) Rupture of a known earthquake fault, as delineated on the most recent AlquistPriolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Refer to Division ofMines and Geology Special Publication 42.

Less Than Significant Impact. According to the Geotechnical Report prepared for the Project,included as Appendix C, there is no presence of active faulting within the Project site (LeightonConsulting Inc. 2018). Furthermore, the Project site does not occur within an "Earthquake Fault Zone," as defined by the State of California in the Alquist-Priolo Earthquake Fault Zoning Act (DOC 2023b). There are no known faults that underlie the Project site, but the Sierra Madre Fault Zone is located approximately 0.25-mile north of the Project site (DOC 2023b; Leighton Consulting Inc. 2018). Therefore, the Project would not expose people or structures to potentialsubstantial adverse effects, including the risk of loss, injury, or death involving rupture of a known earthquake fault. The Project would result in less than significant impacts related to this threshold, and no mitigation is required.
ii) Strong seismic ground shaking?
Less Than Significant Impact. The Project site, as with the entire Southern California region, issubject to secondary effects from earthquakes. There are no known faults that underlie the Projectsite, but the Sierra Madre Fault Zone is located approximately 0.25-mile north of the Project site (DOC 2023b; Leighton Consulting Inc. 2018).

Implementation of the Project would not change the intensity of ground shaking that would occur on the Project site during a seismic event, but it would result in the exposure of a new structure to seismic activity. The proposed building and other improvements would be designed in accordance with the 2022 California Building Code (CBC; CBSC 2022). The CBC contains minimum standards regulating the design and construction of excavations, foundations, retaining walls, and other building elementsto control the effects of seismic ground shaking and adverse soil conditions. The CBC also includes provisions for earthquake safety based on factors such as occupancy type, the types of soil and rock on-site, and the strength of ground motion that may occur at the Project site. Project implementation would also occur consistent with the recommendations outlined in the Geotechnical Report preparedfor the Project.

Compliance with the applicable regulations would reduce potentially significant impacts that mayresult from strong seismic ground shaking at the Project site to less than significant levels.

Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
iii) Seismic-related ground failure, including liquefaction? Less Than Significant Impact. Liquefaction is the loss of soil shear strength due to a buildup ofpore-water pressure during severe and sustained ground shaking. Liquefaction is associated primarily with loose (low density), saturated, fine-to-medium grained, cohesionless soils. As shaking action of an earthquake progresses, soil grains are rearranged and density within a short period of time. Rapid densification of soil results in a buildup of pore-water pressure within saturated soils. When the pore-water pressure approaches the total overburden pressure, then soil shear strength reduces 4-31 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
greatly, and the soil temporarily behaves similarly to a fluid. Effects of liquefaction can include sand boils, settlement, and bearing capacity failures below structural foundations.

According to the Geotechnical Report, the Project site is located within a potential liquefaction hazardzone (Leighton Consulting Inc. 2018). However, groundwaterwas not encountered in the test pits excavated to a maximum depth of 8 feet at the Project site. Historical high groundwater levels were mapped at 20 feet below the ground surface at the site and potential for liquefaction occurring at the Explorer Well Project site is low due to the coarse and well graded alluvium withcobbles and boulders. In addition, the Project would be required to be built in accordance with recommendations in the NASA Optimization Plan and in compliance with applicable building coderegulations (RR GEO-1), which would ensure that the structural integrity of the proposed improvements can withstand hazards, such as liquefaction. Moreover, the Project would notexacerbate liquefaction hazards within the Project site or in the vicinity of the Project site.

As such, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
iv) Landslides?
Less Than Significant Impact. Seismic hazards, such as landslides, would have the potential to damage the proposed infrastructure. However, the Project does not propose any habitablestructures or structures whose height, mass, or materials would pose a hazard in the event of anearthquake. The Project site is considered generally level without significant slopes. As such, the Project site is not considered susceptible to either static or seismically-induced slope instability (Leighton Consulting Inc. 2018, DOC 2023c). Additionally, the Project would be required to be built in accordance with applicable building code regulations (RR GEO-1), which would ensure that the structural integrity of the proposed improvements can withstand seismic hazards.

Through compliance with RR GEO-1, the Project would result in a less than significant impact related to this threshold, and no mitigation is required. b) Would the project result in substantial soil erosion or the loss of topsail? Less Than Significant Impact. The largest source of erosion and topsail loss, particularly in a developed environment, is uncontrolled drainage during construction. Since the Project site would have more than one acre of ground disturbance, compliance with the SWRCB's National PollutantDischarge Elimination System (NPDES) Construction General Permit3 would be required. This would require preparation of a project-specific Storm Water Pollution Prevention Plan (SWPPP),which describes practices to reduce pollutants in stormwater discharges from the construction site by implementing best management practices (BMPs), such as sandbags and detention basins. The Project's potential construction and operational stormwater impacts, and applicable regulatory requirements are addressed further in Section 4.10, Hydrology and Water Quality.

The Project would include asphalt paving of a small area (i.e., 250 square feet) that is not currently paved. However, this area is within the footprint of the former JPL East Parking Lot, so a largerimpervious area existed previously and drained to surrounding pervious areas without issues of soil erosion. Similar to previous drainage patterns for the parking lot, stormwater generated onthe Project site would be conveyed downslope to offsite pervious surfaces as either sheet flow runoff or directed via an existing drainage ditch to an existing spreading basin. Soils in the former JPL East Parking Lot have been classified as "stream deposits" from theArroyo Seco and consist 3 Order No. 2009-0009-DWQ, NPDES No. CAS000002, adopted by the SWRCB on September 2, 2009 (effective for all project sites on July 1, 2010) and most recently amended by Order No. 2012-0006-DWQ on July 17, 2012. 4-32 Environmental Assessment
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primarily of gravelly sands with cobbles and boulders, which are excellent permeable materials(Converse Consultants 2013). Furthermore, the Hahamongna Watershed Park is an area that isdesigned to receive stormwater flows with the downstream Devil's Gate Reservoir serving toretain excess flows. Therefore, the stormwater generated by the Project's minor addition ofapproximately 250 square feet of impervious surface would likely percolate in the surroundingpervious area in a manner that would not substantially increase soil erosion or loss of topsail.

In conclusion, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.c) Would the project be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in onsite oroffsitelandslide, lateral spreading, subsidence, liquefaction, or collapse? Less Than Significant Impact. Secondary seismic hazards related to the underlying geologicunit include several types of ground failure that can occur due to severe ground shaking. Theprobability for each type of ground failure depends on the severity of the earthquake, the site's distance from the fault, the local topography, and subsoil and groundwater conditions, among other factors. In addition, there can be soil engineering characteristics inherent in the underlyingsediments on a site that can adversely affect structures if not appropriately managed duringconstruction, including expansive soils. Liquefaction and landslides are addressed under Thresholds 4.7(a)(iii) and 4.7(a)(iv) above, and there would be a less than significant impact associated with these conditions. Lateral spreading is a liquefaction-related phenomenon; therefore, the above analysis in Threshold 5.7(a)(iii) would also apply to this secondary seismic hazard. Subsidence occurs when a large portion of land is displaced vertically, usually due to the withdrawal of groundwater, oil, or natural gas. Soils that are particularly subject to subsidence include those with high silt or clay content. The Project site is not underlain by clay, and primarilyunderlain by fill and medium dense to very dense subsurface granular soils (Leighton ConsultingInc. 2018). The Project would include groundwater extraction; however, this would not increase the susceptibility of areas near the Project site to subsidence or collapsible soils given that the underlying groundwater basin is adjudicated and parties subject to the Raymond Basin Judgment,including PWP, are limited in the amount of groundwater that can be extracted based on thebasin's safe yield. Safe yield of a groundwater basin is defined as the supply which can continuously be withdrawn without permanent and progressive lowering of the water table.Without lowering of the groundwater table, the Project would not result in subsidence impacts.

Furthermore, the proposed building that would contain the Explorer Well would be built in compliance with applicable building code regulations (RR GEO-1), which would ensure that thestructural integrity of the proposed improvements can withstand seismic hazards. Additionally, theProject would comply with all recommendations as set forth in the Geotechnical Report, which would minimize adverse safety effects associated with unstable geologic units or soils to the maximum extent practicable. As such, the Project would result in a less than significant impactrelated to this threshold, and no mitigation is required.d) Would the project be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial risks to life or property? Less Than Significant Impact. Expansive soils are soils that swell when they absorb water and shrink as they dry, such as pure clay soils and claystone. The hazard associated with expansivesoils is that they can overstress and cause damage to the foundation of buildings set on top ofthem. As stated under Threshold 4.71, the Project site is not underlain by clay, and expansive native soils were not encountered or expected within this portion of the City (Leighton ConsultingInc. 2018). Additionally, the Project would be built in compliance with applicable building code 4-33 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
regulations (RR GEO-1), which would ensure that the structural integrity of the proposedimprovements can withstand seismic hazards. Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.e) Would the project have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not availablefor the disposal of waste water? No Impact. There are no proposed sanitary facilities associated with the Project. Therefore, theProject would result in no impact related to this threshold, and no mitigation is required. f) Would the project directly or indirectly destroy a unique paleontological resource or site or unique geological feature?
Less Than Significant With Mitigation. A paleontological resources records search andliterature review for the Project was conducted at the Vertebrate Paleontology Section of theNatural History Museum (NHM), Los Angeles County in July 2023. The records search includeda 1^-mile radius around the Project site and was conducted by NhlM staff. The purpose of thesearch was to identify paleontological resources or unique geological features previouslyrecorded within and around the Project site and to assess the overall paleontological sensitivity for the Project site. The records search conducted at the NhlM did not identify any previously recorded paleontological resources or unique geological features that lie directly within the Projectsite. However, several fossil localities have been documented nearby from the same sedimentary deposits that occur in the Project site, either at the surface or a depth. These paleontological resources include mammoth (Mammuthus), horse (Equus), sabertooth cat (Smilodon), turkey(Meleagris), and several uncatalogued invertebrates.Only one of the geologic units underlying the Project site, Quaternary older alluvial sediments(Qoa), has as much as a moderate potential to yield paleontological resources. Therefore,excavations less than approximately five feet in depth, within the geologic materials overlying theQoa deposits, are not likely to encounter paleontological resources. Deeper excavations that areover five feet in depth could expose paleontological resources. If paleontological resources wereencountered and damaged by heavy equipment, a significant impact related to this thresholdcould result.

Therefore, to avoid impacts to paleontological resources, the Project would implement MM GEO-1, which requires that a qualified Paleontologist be retained for on-call services in theevent of the discovery ofpaleontologically sensitive rock formations (i.e., Quaternary older alluvialsediments) during ground disturbance activities. Any discovered resources would be evaluated for significance by the paleontologist and appropriate exploration, salvage, and curation of significant paleontological resources, if necessary, would also be conducted, and a mitigation plan would be developed. With implementation of MM GEO-1, impacts related to this threshold would be less than significant.

MITIGATION MEASURES
MM GEO-1 Prior to commencement of earthmoving activities, the City shall retain a qualified Paleontologist, for on-call services in the event of a discovery of paleontologically sensitive rock formations (i.e., Quaternary older alluvial sediments) during grounddisturbance activities. The Paleontologist shall be present at the pre-gradeconference; and shall establish, in cooperation with the Contractor, procedures fortemporarily halting or redirecting work to permit the sampling, identification, andevaluation of any discovered paleontological resources. Should these resources 4-34 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
be found during ground-disturbing activities for the Project, the Paleontologist shall first determine whether it is a significant paleontologically sensitive fossil locality or rock formation. If the above-mentioned resources are found during earthmoving activities, the Paleontologist shall formulate a report and a mitigation plan inconsultation with the City of Pasadena. For paleontological resources, thedisposition of the resources shall be subject to approval by the City. All recovered paleontologically sensitive fossils and rock formations shall be deposited in an accredited institution or museum, such as the Natural History Museum of Los Angeles County. If resources are discovered, work may proceed in other areas ofthe Project site, subject to the direction of the Paleontologist. 4-35 Environmental Assessment
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Initial Study/Mitigated Negative Declaration

4.8 GREENHOUSE GAS EMISSIONS
Potentially
Significant
Impact
Less Than
Significant
With
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the Denvironment? b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of D
greenhouse gases?
D
D
^
^
D
D

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to greenhouse gas emissions.

Impact Discussion
a) Would the project generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
Less Than Significant Impact. Climate change refers to any significant change in temperature,precipitation, or wind patterns over a period of time. Climate change may result from natural factors, natural processes, and human activities that change the composition of the atmosphere and alter the surface and features of the land. Significant changes in global climate patterns haverecently been associated with global warming, which is an average increase in the temperature of the atmosphere near the Earth's surface; this is attributed to an accumulation of greenhouse gas (GhlG) emissions in the atmosphere. GHGs trap heat in the atmosphere which, in turn, increases the Earth's surface temperature. Some GHGs occur naturally and are emitted to theatmosphere through natural processes, while others are created and emitted solely throughhuman activities. The emission of GHGs through fossil fuel combustion in conjunction with other human activities are closely associated with global warming.

GHGs, as defined under California's Assembly Bill (AB) 32, include carbon dioxide (002),methane (€N4), nitrous oxide (N20), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), andsulfur hexafluoride (SFe). General discussions on climate change often include water vapor, ozone, and aerosols in the GHG category. Water vapor and atmospheric ozone are not gases that are formed directly in the construction or operation of development projects, nor can they be controlled in these projects. Aerosols are not gases. While these elements have a role in climatechange, they are not considered by either regulatory bodies, such as CARB, or climate changegroups, such as the Climate Registry, as gases to be reported or analyzed for control. Therefore, no further discussion of water vapor, ozone, or aerosols is provided.

GHGs vary widely in the power of their climatic effects; therefore, climate scientists haveestablished a unit called Global Warming Potential (GWP). The GWP of a gas is a measure ofboth potency and lifespan in the atmosphere as compared to C02. For example, since €N4 and N20 are approximately 28 and 265 times more powerful than C02, respectively, in their ability to trap heat in the atmosphere, they have GWPs of 28 and 265, respectively (C02 has a GWP of 1).

Carbon dioxide equivalent (C02e) is a quantity that enables all GHG emissions to be consideredas a group despite their varying GWPs. The GWP of each GHG is multiplied by the prevalence of 4-36 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
that gas to produce C02e. The atmospheric lifetime and GWP of selected G\-\Gs are summarized in Table 9, Global Warming Potentials and Atmospheric Lifetimes.

TABLE 9

GLOBAL WARMING POTENTIALS AND ATMOSPHERIC LIFETIMES
Greenhouse Gas (ppt)
Atmospheric Lifetime
(years)
Global Warming
Potential
(100-yeartime horizon)
Carbon Dioxide (C02) 50.0-200.0 1Methane (CH4) (ppb)Nitrous Oxide (N20) (ppb)

12.4 121.0
28 265
HFC-134a
PFC-14 Tetrafluoromethane (CF4)

13.4 50,000.0
1,300
6,630
PFC-116 Hexafluoroethane (C2Fe)Sulfur Hexafluoride (SFe) 10,000.0
3,200.0
11,100
23,500
ppt: parts per trillion; ppb: parts per billion; MFC: hydrofluorocarbons; PFC: perfluorocarbons.Source: IPCC 2013.

State of California Regulations and Legislation
Assembly Bill 32 - the California Global Warming Solutions Act of 2006 AB 32, the California Global Warming Solutions Act of 2006, recognizes that California is the source of substantial amounts of GHG emissions. The statute states that:

Global warming poses a serious threat to the economic wellbeing, public health,natural resources, and the environment of California. The potential adverseimpacts of global warming include the exacerbation of air quality problems, areduction in the quality and supply of water to the State from the Sierra snowpack,a rise in sea levels resulting in the displacement of thousands of coastalbusinesses and residences, damage to marine ecosystems and the naturalenvironment, and an increase in the incidences of infectious diseases, asthma,and other human health-related problems.

To avert these consequences, AB 32 established a State goal of reducing GHG emissions to 1990 levels by the year 2020, which is a reduction of approximately 15 percent from forecasted emission levels, with further reductions to follow (CARB 2011). Further reductions have been setby subsequent legislation. Executive Order (EO) B-30-15 establishes a GHG reduction goal of 40percent less than 1990 levels by the year 2030, with the ultimate goal to reduce GHG emissions by 80 percent of 1990 levels by the year 2050 (Executive Order S-3-05) On September 8, 2016,the Governor signed Senate Bill 32 (SB 32) to codify the GHG reduction goals of Executive Order B-30-15 and requiring the State to reduce GHG emissions by 40 percent below 1990 levels by2030 (Health and Safety Code Section 38566). This goal is expected to keep the State on track to meeting the goal set by EO S-3-05 of reducing GHG emissions by 80 percent below 1990 levels by 2050. SB 32's findings state that CARB will "achieve the state's more stringent greenhousegas emission reductions in a manner that benefits the State's most disadvantaged communitiesand is transparent and accountable to the public and the Legislature." 4-37 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
There are also several regulations and legislation that cover a broad variety of emission sources, which include:
• Cap & Trade - These involve market-based compliance mechanisms which include five protocols for offset compliance projects.Building Energy Efficiency Standards -The Energy Commission's 2013 Building EnergyEfficiency Standards are 25% more efficient than previous standards for residentialconstruction and 30% better for nonresidential construction.

Advanced Clean Cars Standards - GHG reductions from passenger vehicles for modelyears 2017-2025 under the Low Emission Vehicle standards.Water Appliance Standards-The Energy Commission's 2015 Water Appliance Standards are projected to save 10 billion gallons in the first year and increases to 100 billion gallonsof water per year. These standards apply to toilets and urinals; residential lavatory faucets; kitchen faucets; and public lavatory faucets.Low Carbon Fuel Standards -10% reduction in carbon intensity of transportation fuels.Renewable Portfolio Standard - Mandates that energy production in California from renewable energy sources is phased-in from 20 percent in 2010, 33 percent by 2020, 60percent by 2030, and 100 percent carbon-free by 2045.

Mandatory Commercial Recycling - Establishes recycling requirements for businesses that generate 4 or more cubic yards of commercial solid waste per week and multifamily residential dwellings with 5 or more units.

Local
The City of Pasadena has prepared and adopted a Climate Action Plan (CAP) (City of Pasadena 2018). The City's CAP includes the following components: a summary of existing state and localinitiatives addressing climate change; community wide GHG inventory and emissions forecasts;GHG reduction goals, measures, and actions; plans of implementation and monitoring of the plan;and adaptation strategies and climate change preparedness. The City's CAP builds upon theCity's prior sustainability efforts, such as the Green City Action Plan and provides a framework to further reduce GHG emissions throughout the City.

The CAP Consistency Checklist (Checklist) is intended to be a tool for new development projects to demonstrate consistency with Pasadena's CAP, which is a qualified GHG emissions reduction plan in accordance with CEQA Guidelines Section 15183.5. Projects that meet the requirements of the Consistency Checklist would be deemed to be consistent with the City's CAP. The followingoptions are provided by the City for new development projects to establish consistency with the CAP.

Option A requires that the new development project apply sustainable developmentactions, as deemed appropriate by the CAP, which would become conditions of the entitlement for approval of the Project.Option B requires that the Project demonstrate consistency with the applicable Pasadena's per service population GHG efficiency threshold.

Option C requires that the Project achieve Net Zero GHG Emissions, which requiresquantifying the project's GHG emission levels and demonstrating that the Project would not result in a net increase in GHG emissions.
4-38 Environmental Assessment
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A consistency analysis for Option B is detailed below. The following analysis used CalEEMod to quantify GHG emissions associated with the Project, per the recommendation of the CAPConsistency Checklist. The formula to calculate the proposed Project's emissions is as follows:

Proposed Project's GHG Efficiency=Annual GHG Emissions/Service Population Annual GHG Emissions: construction emissions (amortized over 30 years) + operational emissions for the Proposed ProjectService Population: Residents + Full-time employees The CAP details that the proposed Project must be able to demonstrate a GHG efficiency, whichis less than or equal to the threshold listed below for the Project's first operational year in order to be considered consistent with the CAP and State targets. Table 10 contains the efficiency thresholds from the City of Pasadena's CAP.

TABLE 10

CITY OF PASADENA CLIMATE ACTION PLAN

EFFICIENCY THRESHOLDS
Project's First Operational Year
2017-2020
Threshold

5.63 MTC02e/SP
2021 - 2025
2026 - 2030
2031 - 2035

4.56 MTC02e/SP

3.57 MTC02e/SP

2.73 MTC02e/SP
MTC02e: metric tons of carbon dioxide equivalent; SP: service person.Source: City of Pasadena 2018.

The Project's first operational year would likely occur between 2026. Therefore, the 3.57 metrictons of carbon dioxide equivalent (MTC02e)/service person (SP) threshold is appropriate for this analysis.Based on the proposed construction activities, the principal source of construction GHG emissions would be internal combustion engines of construction equipment, on-road constructionvehicles, and workers' commuting vehicles. GHG emissions from construction activities were obtained from the CalEEMod model, described above. The estimated construction GHG emissions for the Project would be 700 MTC02e, as shown in Table 11.

TABLE 11

ESTIMATED GREENHOUSE GAS EMISSIONS

FROM CONSTRUCTION
Source
Emissions
(MTCOze)
2024 3052025 395
Total 700
MTCOze: metric tons of carbon dioxide equivalent.Notes:

Totals may not add due to rounding variances.

Detailed calculations in Attachment A.
4-39 Environmental Assessment
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Operational GHG emissions would come primarily from electricity and mobile trips. Estimated Project operational GHG emissions are shown in Table 12.

TABLE 12

ESTIMATED ANNUAL GREENHOUSE GAS

EMISSIONS FROM PROJECT OPERATION
Source
Emissions
(MTC02e/yr.)
Area <1EnergyMobile
45 3
WasteWater
Total
<1<1
48 MTC02e/yr.: metric tons of carbon dioxide equivalent per year.Notes:

Totals may not add due to Founding variances.
• Detailed calculations in Attachment A.

Because impacts from construction activities occur over a relatively short period of time, they contribute a relatively small portion of the overall lifetime project GHG emissions. In addition, GHGemission reduction measures for construction equipment are relatively limited. The City's ClimateAction Plan and subsequent guidance recommend that construction emissions be amortized over a 30-year project lifetime so that GHG reduction measures address construction GHG emissionsas part of the operational GHG reduction strategies (City of Pasadena 2018). Therefore,construction and operational emissions are combined by amortizing the construction emissionsover an assumed 30-year project lifetime and adding the annualized construction emissions to the annual operational emissions. The total GHG emissions attributable to the Project is shown in Table 13 and evaluated against the Option B efficiency threshold. 4-40 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
TABLE 13

ESTIMATED TOTAL PROJECT ANNUAL

GREENHOUSE GAS EMISSIONS
Source
Emissions
(MTC02e/yr.a)
Construction AmortizedOperations (see Table 12)
23a
48 Total Annual Project GHG emissions"
Service Population"
71 16,080
Project-level GHG efficiency
(MTC02e/SP/year) 0.004
City of Pasadena GHG Efficiency Threshold
(MTC02e/SP/year)
Exceed Threshold?

3.57 No
MTCOze/yr.: metric tons of carbon dioxide equivalent per year; GHG:greenhouse gas; SP: service person.bc Total derived by dividing construction emissions (see Table 11) by 30.

Total annual emissions are the sum of amortized constructionemissions and operational emissions.

The service population was determined based on the followingassumptions, which were developed in coordination with PWP staff using the latest information available to PWP:
• The projected production of the Explorer Well is 1,600 gallons per minute, or approximately 2,581 acre-feet per year.

Residential water use was approximately 96 gallons per capitaper day in 2019, which adds up to 35,040 gallons per capita peryear.Residential use accounted for approximately 67 percent ofPWP's overall water use in 2019.
• To determine the amount of water that would go to residential use in the average year, 67 percent of the Explorer Well's production was calculated, which is 1 ,729-acre feet per year (or 563,443,200 gallons per year).
• Dividing the average production of the Explorer Well that will go to residential use (563,443,200 gallons per year) by the 35,040gallons per capita per year of average residential demand, aservice population of 16,080 PWP residential customers was determined.

Based on Census data for the City of Pasadena, the Project would serve an estimated 16,080residents (Census 2022). As shown in Table 13, the Project's GHG efficiency is 0.004MTC02e/SP/year due to the large number of residents it would serve and the very low amount of GHG emissions associated with the development of the Project. Therefore, the Project wouldresult in GHG emissions that do not exceed the City's applicable GHG efficiency threshold, andconsequently the Project demonstrates consistency with the City's CAP via Option B. Aspreviously noted, this report only evaluates the project against Option B criteria.Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.b) Would the project conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases? Less Than Significant Impact. The quantitative goal ofAB 32 was to reduce GHG emissions to 1990 levels by 2020, and the goal of SB 32 is to continue with the timeline by reducing emissions 40 percent below 1990 levels by 2030. Plans and regulations (e.g., Regional Transportation Plan/Sustainable Community Strategy, GHG emissions standards for vehicles, and the 4-41 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Low Carbon Fuel Standard) are being implemented at the statewide level and are aimed at reducing GHG emissions from major sources, such as transportation exhaust and building energyconsumption, rather than replacement of small utility infrastructure elements. Since the Project would not result in a substantial increase in vehicle trips related to inspection and maintenance activities, the Project would not conflict with plans to reduce motor vehicle trips. The Project wouldimprove the resiliency of the local water supply system and consequently lessen dependence onimported water. Local water supplies require less energy to transport and can result in less GHGemissions when compared to imported water, which utilizes a significant amount of energy topump and transport water from Northern California and the Colorado River. As such, the Project would not conflict with or obstruct implementation ofAB 32 or SB 32.

The City's Water Integrated Resources Plan (WIRP) adopted in 2011, identifies a preferred water resource portfolio with emphasis on water conservation and local water supply. The CAP states, "The WIRP, adopted in 2011, calls for a long-term water resource strategy through 2035 andcontains information on PWP's water demands, water supply, and conservation options. The plan identifies a preferred water resource portfolio that includes aggressive water conservation andincreasing local water supplies. These actions will reduce GHG emissions by reducing demand for imported water which utilize significant energy to pump water from Northern California and the Colorado River" (City of Pasadena 2018).

The Project would increase the resiliency of local water supplies which is consistent with theCAP'S GHG reduction measure of increasing access to local water supplies. Groundwater in the Raymond Groundwater Basin is mainly replenished from rainfall in the area, thereby providing alocal sustainable water source. Implementation of the Project would reduce dependence on imported water. Because the CAP has identified development of local water supplies as part of the CAP'S actions to reduce GHG emissions, the Project would be consistent with the CAP and would help the City in meeting its GHG reduction targets. Therefore, implementation of the Project would not conflict with an applicable plan, policy, or regulation adopted for the purpose of reducingGHG emissions.The Project would result in a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to GHG emissions were identified; therefore, no mitigation measures are required.
4-42 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.9 HAZARDS AND HAZARDOUS

MATERIALS
Less Than
Potentially Significant Less Than
Significant with Significant No
Impact Mitigation Impact Impact
Would the project:
a) Create a significant hazard to the public or the
environment through the routine transport, use,ordisposal of hazardous materials? b) Create a significant hazard to the public or the
environment through reasonably foreseeable upset andaccident conditions involving the release of hazardousmaterials into the environment? c) Emit hazardous emissions or handle hazardous or
acutely hazardous materials, substances, or wastewithin one-quari:er-mile of an existing or proposedschool? d) Be located on a site which is included on a list of
hazardous materials sites compiled pursuant to
Government Code Section 65962.5 and, as a result,would it create a significant hazard to the public or theenvironment? e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two
miles of a public airport or public use airport, would theproject result in a safety hazard or excessive noise forpeople residing or working in the project area? f) Impair implementation of or physically interfere with an adopted emergency response plan or emergencyevacuation plan? g) Expose people or structures to a significant risk of loss, injury, or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where
residences are intermixed with wildlands?
D
a
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a
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aa
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IMPACT ANALYSIS
Regulatory RequirementsRR HAZ-1 Construction activities are required to comply with existing federal, State, and local regulations regarding hazardous material use, storage, disposal, and transport toprevent risks to public health and safety, including but not limited to regulations set forth by the U.S. Environmental Protection Agency; U.S. Department of Transportation (CFR Title 49, Hazardous Materials Transportation Act; and Title 40261.31, 261.21, and 261.24); Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) (40 CFR parts 300, 311, 355, 370, and 373); Resource Conservation and Recovery Act (RCRA) (40 CFR parts 240-299); Toxic Substances Control Act (40 CFR parts 745, 761 and 763); California Department of Toxic Substances Control (DTSC); California Department of Transportation (Caltrans); California Division of Drinking Water; and the CaliforniaOccupational Safety and Health Administration (CalOSHA). All onsite generated waste during both construction and operation that meets hazardous waste criteria 4-43 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
will be stored, manifested, transported, and disposed of in accordance with applicable regulations and in a manner to the satisfaction of the local Certified Unified Program Agency (CUPA).

Additionally, RRs TRA-1 and TRA-2 from Section 4.17, Traffic and Transportation, related to construction site access and temporary traffic control would be applicable to the analysis ofemergency response and evacuation plans.

Impact Discussion
a) Would the project create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials? b) Would the project create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
Less Than Significant With Mitigation. The Project would draw contaminated groundwaterfrom the Monk Hill subbasin for treatment, which would involve the routine transport (via pipeline) and disposal ofgroundwater containing trace levels of chemicals (volatile organic compounds [VOCs]and perchlorate) that exceed State and Federal MCLs for drinking water.

During installation of the Explorer Well, cuttings would be generated during the borehole drilling and drilling fluids (mud) would be used to cool and lubricate the drill bit. In reverse rotary welldrilling, the method proposed for the Project, the cuttings and drilling fluid move upward inside the drill pipe and the cuttings are discharged by pump. The drilling fluid returns into the borehole via the annular space between the drill pipe and the borehole wall. Drill cuttings and mud couldcontain contaminants from contact with the groundwater.

As such, the Project would implement MM HAZ-1 during the drilling phase of the Explorer Well, where the drill cuttings and mud shall be placed directly into California Department ofTransportation-approved soil bins that would be temporarily stored at the Project site. Wastesamples from these containers shall be analyzed for the "medium-specific parameters" presented in the Sampling and Analysis Plan in NASA'S 2009 Final Remedial Design/RemediaI Action WorkPlan, prepared in accordance with CERCLA requirements. Based on the laboratory results, the waste shall be classified as hazardous or non-hazardous and waste profiles and manifests for thewaste shall be prepared.

During well development, the drilling water would be directed to TSS tanks where solids would settle out. Clarified water would either be recirculated back to the well for drilling or would bedischarged for beneficial reuse to existing spreading basins through temporary at-grade piping.

During Project operation, groundwater will be conveyed to the MHWTP via buried pipelines.Should there be a main break, or other upset condition, the potential release of groundwater to the surface would not present a significant hazard to the public or environment due to the very low levels of contaminants present within the groundwater.

The construction of the Explorer Well would require earthmoving in the area of the former JPL Parking Lot. To determine whether the soils beneath the former parking lot were contaminated, the City contracted with Converse Consultants (Converse) to conduct a Limited Phase II Environmental Site Assessment Report for the adjacent Arroyo Seco Canyon Project, which included the Project site. In September 2015, Converse advanced five soil borings to depths of up to 15-feet below ground surface. Based on soil samples collected, it appears that the former 4-44 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
JPL parking lot has not been significantly impacted by past waste handling activities at JPL. The Converse report concluded that no additional assessment is necessary, and no remediation isrequired (Converse 2016).

Installation of the Project's pipelines would involve trenching excavations. While there is no known contamination of shallow soils along the pipeline alignments, unanticipated contaminants,particularly hydrocarbon-based, is not uncommon in urban areas. However, excavated soils wouldbe managed in compliance with Title 40 of the Code of Federal Regulations and Title 22 of theCalifornia Code of Regulations (RR HAZ-1) and as required by MM HAZ-2, if contaminated soilsare discovered, they would be excavated immediately upon discovery and tested prior to disposal to ensure proper handling and transport in compliance with applicable federal, State, and local regulations governing the handling of hazardous materials.

Construction of the Project would involve the limited transport, storage, use, and/or disposal ofcommon construction-related hazardous materials, including oil and grease, solvents, diesel fuel,and other chemicals in vehicles, trucks, and heavy equipment. These materials could be releasedinto the environment in small amounts in the event of an accident. To prevent environmentalhazards, the handling of hazardous materials used in construction equipment would be conductedin accordance with existing regulations (RR HAZ-1).

In addition to the requirements of regulations set forth in RR HAZ-1, MM HAZ-2 also includesProject-specific measures to avoid impacts associated with hazardous material spills and accidents in and near the Arroyo Seco during construction activities. These include inspecting trucks for oil, gasoline, or other vehicle fluid leaks; locating fueling areas and storage of hazardous materials away from water bodies and drainages; creating a plan for refueling; removinghazardous material spills and contaminated soils; controlling and containing hazardous materialsspills; and ensuring cleanup kits are available.

In summary, all soil and other wastes generated by the Project that require disposal would be subject to laboratory testing; appropriate characterization, classification, and manifestpreparation; and licensed transport as described in RR HAZ-1 and required by MM HAZ-1 andMM HAZ-2. Construction and operation of the Project would not result in a significant hazard to the public or the environment through implementation of RR HAZ-1 and MM HAZ-2 (construction-period only). With mitigation, the Project would result in a less than significantimpact related to this threshold. c) Would the project emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter-mile of an existing orproposed school? Less Than Significant With Mitigation. Schools or similar facilities located within approximately1/4-mile of the Project site include:

Odyssey Charter School located at 725 Altadena Drive, Altadena approximately 0.25 mileeast-of the Project site.

Little Finch Forest School located at the JPL Parking Lot Entrance, La Canadaapproximately 0.15 mile north of the Project site.

As discussed under Thresholds 4.9(a) and (b), construction and operation of the Project would involve the handling of potentially hazardous materials/wastes, which would be conducted inaccordance with all applicable local, State, and federal laws. As described above, construction 4-45 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
and operation of the Project would not result in a significant hazard to the public or the environment through implementation of RR HAZ-1 and MM HAZ-2.

In summary, with compliance with RR HAZ-1 and implementation of MM HAZ-2, the Project would have a less than significant impact related to this threshold.d) Would the project be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as aresult, would it create a significant hazard to the public or the environment? Less Than Significant With Mitigation. The JPL campus and off-site areas encompassed by the groundwater plume, have been designated as a Superfund site (i.e., pursuant to CERCLA).

Since the mid-1980s, NASA has investigated and subsequently taken action to clean up groundwater contamination associated with historic waste management practices at the JPL.The groundwater beneath the JPL and surrounding areas is known to contain contaminants, primarily perchlorate, and CTC, a VOC. The analysis of construction and operation of the Project, includingmanagement of drilling wastes and contaminated groundwater associated with the Superfundsite, is addressed under Thresholds 4.8(a) and (b). As discussed, the Project would not result ina significant hazard to the public or the environment through implementation of RR HAZ-1 andMM HAZ-1 (construction-period only).

In summary, with compliance with RR HAZ-1 and implementation of MM HAZ-1, the Project would have a less than significant impact related to this threshold.e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would theproject result in a safety hazard or excessive noise for people residing or workingin the project area? No Impact. There are no airports or airstrips within two miles of the Arroyo Seco Canyon. Thenearest airports are the Burbank Bob Hope Airport and the San Gabriel Valley Airport, which areboth approximately 11 miles from the Project site. The Project would not involve the construction of high-rise structures or involve activities that could pose a safety hazard to helicopter or aircraftoperations or airport activities, nor would it conflict with an airport land use plan. Therefore, the Project would have no impact related to this threshold, and no mitigation is required. f) Would the project impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
Less Than Significant Impact. The City of Pasadena Emergency Operations Plan addresses the City's planned response to emergencies associated with natural disasters and technological incidents. It provides an overview of operational concepts, identifies components of the City's emergency management organization within the Standardized Emergency Management System (SEMS) and the National Incident Management System (NIMS), and describes the overall responsibilities of the federal, State, county entities, and the City for protecting life and propertyand ensuring the overall well-being of the population (Pasadena 2011 a). Further, the Citymaintains a SEMS/NIMS Emergency Response Plan, which addresses planned responses toemergency/disaster situations associated with natural disasters, technological incidents, andnational security emergencies. In case of a disaster, the Pasadena Fire Department is responsible for implementing the plan, and the Pasadena Police Department devises evacuation routes based on the specific circumstance of the emergency.
4-46 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
The Project site Is not located on public-access roads such that emergency vehicle access orevacuation through the site is considered foreseeable. Construction worker vehicles, trucks, delivery vehicles and haul trucks would access the site via 1-210 at the Windsor Avenue off-ramp and head north on Explorer Road to reach the Project site. All construction staging and parking would occur on the Project site, and construction would not require staging along adjacent public roadways or other areas that would disrupt existing traffic patterns. Construction activities associated with the Project would not substantially obstruct Explorer Road, which providesemergency access to the Project area. A400-foot segment of Explorer Road would be realignedas part of the Project. Access to JPL's east gate would be restricted for approximately one week while a section of Explorer Road is realigned. Any closures would be coordinated with JPL priorto implementation. The road realignment would allow for through traffic to continue to utilize Explorer Road while the well is constructed.

Once the Project is built, access to the Explorer Well would be provided from Explorer Road vianew all-weather driveways that would provide access to the two proposed access gates.

Additionally, compliance with the Standard Specifications for Public Works Construction (Greenbook) and the City's Supplements and Modifications to the Greenbook (RR TRA-1)regarding maintenance of emergency access at all times; the use of a flagperson to direct traffic,as necessary; and allowing for the continued public use of the Explorer Road at times whenconstruction is not ongoing, would ensure that access impacts relative to this roadway would be less than significant. Temporary traffic control devices are also required to be provided in conformance with the Manual on Uniform Traffic Control Devices (MUTCD)and the CaliforniaSupplement to the MUTCD (RR TRA-2). As such, the Project would not obstruct any emergency response plan or emergency evacuation plan. Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.g) Would the project expose people or structures to a significant risk of loss, injury, or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands? Less Than Significant Impact. The Project site is located within a Fire Hazard Severity Zone ina Local Responsibility Area (LRA) (CAL FIRE 2023). According to mapping prepared by thePasadena Fire Department, the northern portion of the Project site is within an area that is designated as a Very High Fire Hazard Severity Zone (VHFHSZ) (City of Pasadena 2023b).

The Project involves the construction and operation of a new building containing a well. Although the Project site is designated as a VHFHSZ, the Project site does not currently contain large number of trees or other vegetation with potential to burn during a wildfire event. Further, the Explorer Well building would be designed and constructed in accordance with the Pasadena FirePrevention Code (Chapter 14.28 of the City's Municipal Code), which adopts the California Fire Code with changes and additions to the adopted code.The Project would not involve construction or operation of habitable structures that may expose people to wildfire hazards in the area. Maintenance workers that would come to the area wouldbe in the area for limited time periods and could readily avoid or evacuate from the Project site in the event of a wildfire.Also, Project construction would temporarily increase the risk of wildfire due to use of constructionequipment. The City's Fire Prevention Code includes fire safety measures that would be followedduring construction as specified in RR PS-1. With adherence to RR PS-1, the Project would result in a less than significant impact related to this threshold, and no mitigation is required. 4-47 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

MITIGATION MEASURES
MM HAZ-1 During the drilling of the Explorer Well, the drill cuttings and mud shall be placed directly into California Department of Transportation-approved soil bins and the bins would be temporarily stored on site. Waste samples from these containersshall be analyzed for the "medium-specific parameters" presented in the Samplingand Analysis Plan in NASA'S 2009 Final Remedial Design/Remedial Action(RD/RA) Work Plan, prepared in accordance with CERCLA requirements. Basedon the laboratory results, the waste shall be classified as hazardous ornon-hazardous and waste profiles and manifests for the waste shall be prepared.

The City shall coordinate with NASA to ensure the selection of a U.S.

Environmental Protection Agency (EPA)-certified waste disposal facility and a licensed transporter to haul off the waste.

MM HAZ-2 During all earthmoving and construction activities, the City shall require the Contractors to implement the following measures:

Trucks and equipment entering the site shall be inspected to be free from oil, gasoline, or other vehicle fluid leaks.Equipment fueling areas shall be located outside of the spreading basins andany jurisdictional waters as identified by the United States Army Corps ofEngineers (USAGE) and the California Department of Fish and Wildlife (CDFW).

Hazardous materials shall not be stored on the site. Any hazardous material spills and/or contaminated soils shall be excavated immediately upondiscovery and tested prior to disposal to ensure proper handling and transportin compliance with applicable federal, State, and local regulations governing the handling of hazardous materials.The Contractor shall maintain hazardous materials spill control, containment, and cleanup kits of adequate size and materials for potential accidental spillsand releases. 4-48 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.10 HYDROLOGY AND WATER QUALITY Potentially Significant Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surfaceor ground water quality? b) Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that theproject may impede sustainable groundwatermanagement of the basin? c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of astream or river or through the addition of impervioussurfaces, in a manner which would:
i) result in a substantial erosion or siltation on- or off-site;ii) substantially increase the rate or amount of surface runoff in a manner which would result in flooding onor offsite; iii) create or contribute runoff water which would exceed the capacity of existing or planned stormwaterdrainage systems or provide substantial additionalsources of polluted runoff; or iv) impede or redirect flood flows?
d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management
plan?
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IMPACT ANALYSIS
Regulatory ReciyirementsRR HYD-1 The Explorer Well would be operated in compliance with Section 64560 of the California Code of Regulations, which provides requirements associated withinstallation of new drinking water production wells and is administered by theCalifornia Division of Drinking Water (DDW). The new well must also comply withDDW-specified minimum horizontal distances to sanitary hazards. Additionally, theproposed well is required to comply with the community water system wellrequirements in the California Department of Water Resources Bulletins 74-81 and 74-90 and the American Water Works Associated Standard A100-06 (Water Wells).

RR HYD-2 The Project is required to comply with the Statewide National Pollutant Discharge Elimination System (NPDES) Permit for Drinking Water System Discharges to Waters of the United States (Order WQ 2014-0194-DWQ, General Order No.CAG14001). 4-49 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
Impact Discussion
a) Would the project violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or ground water quality? Less Than Significant Impact. Since the Project site would have more than one acre of ground disturbance, compliance with the SWRCB's NPDES Construction General Permit would be required. This would require preparation of a project-specific SWPPP, which describes practices to reduce pollutants in stormwater discharges from the construction site by implementing BMPs,such as sandbags and detention basins. As such, there would not be substantial pollutants introduced into storm water runoff, including sediment, during construction of the Project.Handling of hazardous materials and wastes during construction would occur in compliance with federal, State, and local requirements (RR HAZ-1), as discussed in Section 4.8, Hazards and Hazardous Materials.

Per RR HYD-1, construction and operation of the Explorer Well would require an amended domestic water supply permit pursuant to Section 64560 of Title 22 of the California Code of Regulations. This would require submittal of a permit amendment application and technical report to the DDW that would include a source water assessment; documentation demonstrating that awell site control zone with a 50-foot-radius around the site can be established for protecting the source from vandalism, tampering, or other threats; design and specifications; and CEQA documentation (i.e., this IS/MND, if adopted). These regulations also require that after DDW has provided written or oral approval of the amendment application and the well has been constructed, the water agency (in this case Pasadena Water and Power) would be required to submit a copy of the well permit from the City, California Department of Water Resources (DWR) well completionreport, a copy of any pump tests required by DDW, results of all required water quality analyses,and as-built plans. Finally, the new well must also comply with DDW-specified minimum horizontaldistances to sanitary hazards (e.g., manholes, storage tanks, septic tanks). In addition to DDWrequirements pursuant to Title 22, the new well must be constructed in compliance with thecommunity water system well requirements in the DWR Bulletins 74-81 and 74-90 and the American Water Works Association Standard A100-06 (Water Wells (NASA 2014). Through compliance with applicable permitting and other regulatory requirements (RR HYD-1), the Explorer Well would not violate water quality standards/waste discharge requirements or otherwise degrade water quality. On the contrary, installation of the proposed well wouldcontribute to the cleanup of the JPL Superfund site in a shorter timeframe than the existingremedial infrastructure.

As per RR HYD-2, the Project would continue to comply with SWRCB Order WQ 2014-0194-DWQ, "Statewide NPDES Permit for Drinking Water System Discharges to Waters ofthe United States" that currently applies to the existing facilities. The Order provides regulatory coverage for discharges a water purveyor may undertake to comply with the federal Safe Drinking WaterAct, the California Health and Safety Code, and the State Water Board's Division of DrinkingWater permitting requirements for providing reliable delivery of safe drinking water. Among the authorized discharges included in the Order are those due to groundwater supply well flushing orpump-to-waste; groundwater well development, rehabilitation, and testing; and groundwatermonitoring for purpose of supply well development, rehabilitation, and testing. Furthermore, discharges authorized under this Order that are put to multiple use or beneficial reuse are not required to be monitored and generally not required to obtain any other waste dischargerequirements. The Project complies with the provisions in the order and its discharges to spreading basins allowing for groundwater recharge is considered a beneficial reuse. Therefore,discharges into surface waters from the Project would not violate waste discharge requirementsor otherwise violate water quality. 4-50 Environmental Assessment
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Initial Study/Mitigated Negative Declaration
With adherence to RR HYD-1, RR HYD-2, and RR HAZ-1, the Project would result in a less than significant impact related to this threshold, and no mitigation is required. b) Would the project substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project may impedesustainable groundwater management of the basin? Less Than Significant Impact. The Sustainable Groundwater Management Act of 2014 (SGMA)requires the designation of groundwater sustainabitity agencies (GSA's) by one or more local agencies and the adoption of groundwater sustainability plans (GSPs) for basins designated as medium- or high-priority by the DWR. SGMA applies to all California groundwater basins andrequires the DWR to prioritize California's 517 groundwater basins and subbasins as either high,medium, low, or very low (DWR 2023). The Raymond Basin, which underlies the City ofPasadena, was determined by DWR to be "Very Low" priority and is already a fully adjudicatedbasin, therefore, not subject to the requirements to form a GSA or to develop a GSP.

The Raymond Basin Judgment adjudicates the groundwater rights in the Raymond Basin. Parties to the Judgment (pumpers) are decreed pumping rights based on the safe yield of the aquifer.The City's decreed groundwater pumping rights include 4,464 acre feet per year in the Monk Hill subbasin. The addition of the proposed Explorer Well would increase the City's capacity forpumping by 1,600 gpm, but the amount of water that is pumped from the underlying Monk Hill subbasin will remain limited by the Judgment. This includes pumping as it relates to the operationof the Project as well as the construction of the Project. During construction, groundwater would be extracted during development of the Explorer Well and directed to TSS tanks. From these tanks the water would either be recirculated back to the well for drilling, off-loaded for disposal, or discharged to PWP's spreading basins which would allow for much of the water to percolate back into the groundwater aquifer. Temporary piping would be used to direct the discharge from the TSS tanks near Explorer Well to the spreading basins to the west and would consist of aboveground pipes. During both the well development stage and during operation, the Project would not decrease groundwater supplies because more water cannot be pumped from the basin than is allowed pursuant to the Raymond Basin Judgement.

The Project also would not substantially decrease groundwater supplies through its use of water.

Historically, about 40% of PWP's water supplies have come from groundwater. However, therelatively minor water use anticipated for the Project during both construction and operation wouldnot have a substantial impact on groundwater supplies given the relatively small amount of waterrelative to the overall City water supply.For example, construction of the Project would involve earthwork/grading that would require water for dust suppression to comply with SCAQMD Rule 403. Also, operation of the Project would involve minor use of water for general facility maintenance, including for potential landscaping.

The water for these uses would be provided from the municipal water system. The quantity ofwater that would be used during construction and operation would have a negligible effect on the City's overall water demand. Moreover, such additional water demand would have no effect on the amount of water withdrawn from groundwater supplies, as such withdrawal is controlled by the adjudication.

The Project also would not substantially interfere with groundwater recharge. The Project would include asphalt paving of a small area (i.e., 250 square feet) that would drain to surrounding pervious areas, as either sheet flow runoff or directed via an existing drainage ditch to an existingspreading basin. Soils in the former JPL East Parking Lot have been classified as "streamdeposits" from the Arroyo Seco and consist primarily of gravelly sands with cobbles and boulders which are excellent permeable materials that would allow percolation into the ground. Similarly, 4-51 Environmental Assessment
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drainage directed to the spreading basins would percolate and contribute to groundwater recharge. Therefore, the Project's minor addition of approximately 250 square feet of impervious surface would not have a substantial effect on recharge of the underlying groundwater basin.

In conclusion, the Project would result in a less than significant related to this threshold, and nomitigation is required.c) Would the project substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through theaddition of impervious surfaces, in a manner which would:i) result in a substantial erosion or siltation on- or off-site? Less Than Significant Impact. The Project has the potential to result in erosion and siltation during construction. Development and implementation of a SWPPPforthe Project, as required incompliance with the SWRCB's General Construction Permit, would ensure potential effects related to erosion and siltation are reduced to less than significant levels during construction.

The Project would result in a minor increase in impervious surfaces compared to the existingcondition once built. However, the areas where impervious surfaces would be added are withinthe footprint of the former JPL East Parking Lot. Soils in the former JPL East Parking Lot have been classified as "stream deposits" from theArroyo Seco and consist primarily of gravelly sands with cobbles and boulders, which are excellent permeable materials that would allow drainagefrom the Project's paved area to percolate into the ground. Therefore, operation of the Project would result in less than significant impacts related to erosion and siltation.

Overall, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
ii) substantially increase the rate or amount of surface runoff in would result in flooding on- or offsite;
manner which
iii) create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff; or
Less Than Significant Impact. The rate of stormwater runofffrom the Project site would increaseminimally from pre-Project conditions since there would be a small amount of additionalimpervious surface area that would occur with the Project. Stormwater generated on the Projectsite would be conveyed downslope to offsite pervious surfaces as either sheet flow runoff or directed via an existing drainage ditch to one of the existing spreading basins. In either case, drainage would primarily percolate into the ground. Stormwater that does not locally percolatewould flow into the Devil's Gate Reservoir, which is an area that is designed to receive and retain excess flows for flood protection. Therefore, the Project would not result in flooding on- or off-site,nor would the Project contribute runoff water that would exceed the capacity of the stormwaterdrainage system. Thus, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
iv) impede or redirect flood flows?
No Impact. The Project would result in no changes to the flow of the Arroyo Seco. As discussed under Threshold 2.101(1) above, the Project would not substantially alter the existing drainagepattern of the site. The Federal Emergency Management Agency (FEMA) prepares Flood 4-52 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Insurance Rate Maps for 100-year floods, meaning an area has a one percent chance of being inundated during a 12-month period, and 500-year floods, which means that in any given year, the risk of flooding in a designated area is 0.2 percent. As demarcated by FEMA, the Project is not within a flood hazard zone and is determined as "Zone X," meaning areas determined to beoutside the 0.2 percent annual chance floodplain (FEMA 2008). Therefore, the Project would notimpede or redirect flood flows. The Project would have no impact related to this threshold, and nomitigation is required.d) Would the project, in flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
Less Than Significant Impact. Seiches are large waves generated in enclosed bodies of waterin response to ground shaking. Tsunamis are predominately ocean waves generated by undersealarge magnitude fault displacement or major ground movement. Based on separation of the site from any body of water, seiche impact at this site is highly unlikely. Also, due to the inland locationof this site and finish floor elevation at 1,108 feet above mean sea level, relative to the PacificOcean no tsunami risk exists at this site (Leighton Consulting Inc. 2018).

Earthquake-induced flooding can be caused by failure of dams or other water-retaining structuresbecause of earthquakes. This portion of the Arroyo Seco (upstream of Devil's Gate Dam) is notlocated within a dam failure inundation zone (although various upstream and uphill water tanksand relatively small, enclosed reservoirs could fail and flood the low-lying Arroyo Seco area on the order of a foot deep). Furthermore, substantial amounts of pollutants would not be stored or otherwise occur onsite that could be at risk of release.

Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
e) Would the project conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
No Impact. The Project site is located within an area that is covered by the Hahamongna Watershed Park Master Plan (HWPMP), which governs an area of approximately 300 acres within the Upper Arroyo Seco. The HWPMP provides a framework for managing the recreation, surfacewater, habitat resources, and cultural resources in the HWPMP area for the use and enjoyment of the public. An objective of the HWPMP is to "Maximize groundwater recharge to minimize theamount of water purchased from outside sources." The HWPMP does not specifically address groundwater pumping but recognizes that the City relies on the basin for water supply. Beyondthat, the document lacks detail in this area to be considered a groundwater management plan.The Raymond Basin Judgment adjudicates the groundwater rights in the Raymond Basin. Partiesto the Judgment (pumpers) are decreed pumping rights based on the safe yield of the aquifer.The City's decreed groundwater pumping rights include 4,464 acre feet per year in the Monk Hill subbasin. The addition of the proposed Explorer Well would increase the City's capacity forpumping by 1,600 gpm, but the amount of water that is pumped from the underlying Monk Hillsubbasin will remain limited by the Judgment. This includes pumping as it relates to the operationof the Project as well as the construction of the Project. Therefore, the Project would beimplemented compliant with the Raymond Basin Judgement.Responsibility for the protection of surface and groundwater quality in California lies with the SWRCB and nine RWQCBs. The RWQCB, Los Angeles Region (LARWQCB), has jurisdiction over the drainage area that includes the Project site, and the Los Angeles Regional Board's Basin Plan is the applicable water quality control plan. The Basin Plan designates beneficial uses for 4-53 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
surface and groundwaters, sets objectives to protect the designated beneficial uses, anddescribes implementation programs to protect waters in the region. The SWRCB has stipulated that the City's discharge of pumped groundwater to the spreading basins is considered "beneficial reuse" and is distinguished from other non-storm water discharges. However, the discharges mustbe fully contained within the spreading basins. By meeting these conditions, the Project wouldneither conflict with nor obstruct implementation of the LARWQCB's Basin PlanIn conclusion, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to hydrology and water quality were identified; therefore, nomitigation measures are required. 4-54 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.11 LAND USE AND PLANNING Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Physically divide an established community?b) Cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted forthe purpose of avoiding or mitigating an environmental effect?
Da
DD
as
sD

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to land use and planning.

Impact Discussion
a) Would the project physically divide an established community? No Impact. The Project does not involve the displacement of existing residences or the construction of barriers through the developed areas surrounding the Project area. Therefore, the Project would not divide an established community. There would be no impact, and no mitigationis required.b) Would the project cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect?
Less Than Significant Impact. The primary land use planning documents that govern the Projectsite are the City's General Plan and the Pasadena Zoning Code. The Project site's General Planland use designation is Open Space, and zoning designation is OS (Open Space).

The Project would develop a well and associated pipeline, which would be consistent with the Open Space land use designation and zoning. Given that the Project would qualify as a Utility, Minor (defined by the Pasadena Zoning Code as "a utility facility that is necessary to support a legally established use and involves only minor structures...") land use, the Project would notrequire a Conditional Use Permit. Therefore, the Project would be consistent with the land useand zoning designation.

Additionally, the Project site is located within the HWPMP area, which includes approximately 300 acres and is part of the Upper Arroyo Seco. The HWPMP provides a framework for managing therecreation, surface water, habitat resources, and cultural resources in the HWPMP area for theuse and enjoyment of the public. Because the Project consists solely of public works infrastructure facilities and does not affect the public parkland within the HWP or develop any structures/facilitiesthat would be publicly accessible, the requirements of the HWPMP are not applicable to the Project.

Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
4-55 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

MITIGATION MEASURES
No significant impacts pertaining to land use and planning were identified; therefore, no mitigation measures are required.
4-56 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.12 MINERAL RESOURCES Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Result in the loss of availability of a known mineral resource that would be of value to the region and theresidents of the state? b) Result in the loss of availability of a locally-important mineral resource recovery site delineated on a local
general plan, specific plan, or other land use plan?
Da
Da
ss
aD

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to mineral resources.

Impact Discussiona) Would the project result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state? Less Than Significant Impact. According to the City's General Plan, no active mining operationsexist in the City and mining is not a permitted use in the City's Zoning Code. There are two areasin Pasadena that have been identified by the California Geological Society (CGS) as MineralResource Zone (MRZ)-2, which is defined as areas where geologic data indicate that significantPortland Cement Concrete-Grade aggregate resources are present. These two areas are Eaton Wash and Devil's Gate Reservoir, which were both formerly mined for aggregate but are no longer utilized for these purposes (CGS 1982, 2010). The Project site is located within the Devil's GateReservoir area and is identified within the MRZ-2 area. CGS has identified sand and gravel deposits to a depth of 100 feet below the present-day channel surface in the Project site andvicinity (CGS 2010). The construction of the Explorer Well would result in the extraction of some underlying sand, gravel, or arroyo stone resources during drilling activities and may expose theseresources during pipeline excavation and as part of grading activities for Explorer Well andpipeline installations. However, the amounts of materials extracted would be minor and these areas could not reasonably be mined given that they are zoned as OS.Therefore, the Project would result a less than significant impact related to this threshold, and no mitigation is required.b) Would the project result in the loss of availability of a locally-important mineral resource recovery site delineated on a local general plan, specific plan, or otherland use plan? Less Than Significant Impact. There are no identified oil, gas, or geothermal resources orongoing mining/extraction activities at the Project site. As stated above, no active miningoperations exist in the City, as mining is not a permitted use in the City's Zoning Code. The Project would not require mineral resources, nor would it significantly alter the availability of resourceswithin Devil's Gate Reservoir. The removal of perchlorate and VOC from the mid-plume would not significantly impact sand and gravel resources in the reservoir. Additionally, no new structures or facilities would be constructed as part of the Project that could potentially restrict or obstruct future 4-57 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
mineral resource recovery activities within the Project site. Long-term operation and maintenanceactivities for the proposed well and pipeline would not require mineral resources.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to mineral resources were identified; therefore, no mitigation measures are required.
4-58 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.13 NOISE Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project result in:
a) Generation of a substantial temporary or permanent
increase in ambient noise levels in the vicinity of theproject in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies?
b) Generation of excessive groundborne vibration or
groundborne noise levels?
c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has notbeen adopted, within two miles of a public airport or publicuse airport, would the project expose people residing or working in the project area to excessive noise levels?
D
DD
s
nD
D
aD
Dss

IMPACT ANALYSIS
Regulatory RequirementsRR N01-1 In accordance with Section 9.36.080 of the City of Pasadena Municipal Code, it is unlawful for any person to operate any powered construction equipment if theoperation of such equipment emits noise at a level in excess of 85 dBA whenmeasured within a radius of 100 feet from such equipment.

Impact Discussiona) Would the project result in generation of a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance, or applicable standards ofother agencies? Less Than Significant With Mitigation.

Noise-Sensitive ReceptorsNoise-sensitive receptors include land uses where an excessive amount of noise would interfere with normal operations or activities and where a high degree of noise control may be necessary.

Examples include schools, hospitals, and residential areas. Noise sensitive uses proximate to theProject site include residential uses located approximately 195 feet to the east, a church located approximately 2,130 feet to the southeast, and a school located approximately 1,230 feet to theeast.

Existing Noise Levels
An ambient noise monitoring program was conducted to characterize the ambient noise levels at sensitive locations near the Project site. The 24-hour ambient noise level measurements were taken from July 26-28, 2023. Based on observations during the noise monitoring, primary noise sources are due to residential traffic, industrial uses from the JPL facility, pedestrian hiking,off-road motorized vehicles, and native wildlife. 4-59 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
The monitoring was conducted using Larson Davis Laboratories Model 831 and LxT integrating sound level meters (LD 831/LD LxT) which are characterized as Class 1 sound level metersaccording to International Electrotechnical Commission (IEC) 61260 and American NationalStandards Institute (ANSI) S1.11. The LD sound level meters were calibrated before and afteruse.

In addition to the 24-hour monitoring, a short-term ambient noise level measurement for 30 minutes was made, utilizing a Bruel & Kjaer type 2270 sound level meter (also Class 1). All themonitored locations are shown in Exhibit 4-1, Noise Monitoring Locations. The average,maximum, and minimum (Leq, Lmax, and Lmin) values, taken at the short-term location, and the Community Noise Equivalent Level values taken at the 24-hour noise monitoring locations, areshown in Table 14, Ambient Noise Level Measurements. The complete noise monitoring results are included in Appendix D.

TABLE 14

AMBIENT NOISE LEVEL MEASUREMENTS
Location
No. Location
Start Time(Duration)
Noise Levels (dBA)
CNEL | Leq I Lmax | Lmin
Primary
Noise Source(s) Notes
1 Gabrielino Trail - West of 3085 Ridgeview Drive 1:00 PM (24 Hours) 61 55 80 48 Hum and materialhandlingequipment at JPL.Occasional traffic.

Occasional hikers.Native wildlife.Vehicular traffic and off- road motor bikes. 2 Gabrielino Trail - West of 898 Altadena Drive 1:00 PM (24 Hours) 61 54 78 48 Hum and materialhandlingequipment at JPL
Occasional hikers.Native wildlife.Vehicular traffic and off- road motor bikes. 3 Arroyo Seco Basin 2:00 PM (24 Hours) 60 53 66 48
Hum and materialhandlingequipment at JPL.

Occasional hikers.Native wildlife.Vehicular traffic and off- road motor bikes. 4 WestendofAltadena Drive 2:00 PM (24 Hours) 62 52 77 49 Hum and materialhandlingequipment at JPL.

Occasional hikers.Native wildlife.Vehicular traffic and off- road motor bikes. 5 Gabrielino Trail-West of 2923 Crestford Drive 2:27 PM (30 min) 47 56 44 Hum and materialhandlingequipment at JPL.

Occasional hikers.Native wildlife.Vehicular traffic and off- road motor bikes. dBA: A-weighted decibel; CNEL: Community Noise Equivalent Level is a 24-hour average sound level with a penalty for noise occurring at night; Leq:average noise level over a period of minutes or hours expressed as the equivalent noise level for that time period; Lm,x and Lmin: the highest and lowest(respectively) A-weighted sound level that occurs during that noise event; JPL-Jet Propulsion Laboratory; min: minutes.Source: Psomas July 2023.

City of Pasadena
The City of Pasadena has established guidelines and standards in its General Plan and MunicipalCode. The Noise Element recognizes that construction activity is a source of occasional temporary nuisance noise throughout the City and that these and other such nuisance noises are common to cities and, because of their unpredictable nature, must be addressed on a caseby-case basis. 4-60 Environmental Assessment
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PSO M A S
(Rev: 11-06-2023 PLO)R:\Projects\PAS_Pasaden\3PAS013201 - Explorer Well\Graphics\NM\ex_Noise_Monitoring.pdf Explorer Well Project
Initial Study/Mitigated Negative Declaration
The following policies are applicable to the Project:

Policy 7b: The City will encourage limitations on construction activities adjacent to sensitive noise receptors.

Policy 7c: The City will encourage construction and landscaping activities that employ techniques to minimize noise.

The City Municipal Code (Title 9, article IV, Chapter 9.36, Noise Restrictions) is the City's Noise Ordinance. It is the City's policy"... to prohibit unnecessary, excessive and annoying noises fromall sources. Noise at certain levels is detrimental to the health and welfare of the general public".The following sections of the Noise Ordinance are applicable to the Project:Section 9.36.050 -General Noise Sources This is applicable for long-term, operational noise and states "It is unlawful for any person tocreate, cause, make, or continue to make or permit to be made or continued any noise or soundwhich exceeds the ambient noise level at the property line of any property by more than 5 decibels". In accordance with Section 9.36.040, adjustments are made to the allowable noiselevel for steady audible tones, repeated impulsive noise, and noise occurring for limited timeperiods.

Section 9.36.070 - Construction ProjectsThis section is applicable for Construction Projects and states:

A. No person shall operate any pile driver, power shovel, pneumatic hammer, derrick power hoist, forklift, cement mixer, or any other similar construction equipment within a residential district or within a radius of 500 feet therefrom at any time otherthan as listed below:

1. From 7:00 AM to 7:00 PM Monday through Friday;

2. From 8:00 AM to 5:00 PM on Saturday; and

3. Operation of any of the listed construction equipment is prohibited on Sundays and holidays.

B. No person shall perform any construction or repair work on buildings, structures, or projects within a residential district or within a radius of 500 feet therefrom insuch a manner that a reasonable person of normal sensitiveness residing in thearea is caused discomfort or annoyance at any time other than as listed below:

1. From 7:00 AM to 7:00 PM Monday through Friday;

2. From 8:00 AM to 5:00 PM on Saturday; and

3. Performance of construction or repair work is prohibited on Sundays and holidays.

C. For purposes of this section, holidays are New Year's Day, Martin Luther King Jr.

Day, Lincoln's Birthday, Washington's Birthday, Memorial Day, Independence Day,Labor Day, Veterans Day, Thanksgiving Day, Day after Thanksgiving, and Christmas.
4-61 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Section 9.36.080 - Construction EquipmentThis section states that "It is unlawful for any person to operate any powered construction equipment if the operation of such equipment emits noise at a level in excess of 85 dBA when measured within a radius of 100 feet from such equipment".

9.36.170-Exemptions.This section provides the following exemptions to the City's Noise Ordinance:

A. This chapter is not intended to regulate construction or maintenance and repair activities conducted by public agencies or their contractors necessitated byemergency conditions or deemed necessary by the city to serve the best interestsof the public and to protect the public health, safety, and welfare. These operationsmay include, but are not limited to, street sweeping, debris and limb removal,removal of downed wires, restoring electrical service, repairing traffic lights,unplugging sewers, vacuuming catch basins, repairing water hydrants and mains,gas lines, oil lines, storm drains, roads, sidewalks, etc.

B. Notwithstanding the ordinance codified in this chapter, the city manager is authorized to permit special events to generate noise levels up to the limitsspecified in the noise element of the city's general plan.

C. Notwithstanding the ordinance codified in this chapter, the general manager of the Rose Bowl is authorized to permit events licensed by the Rose Bowl Operating Company to generate noise levels up to the limits specified in the noise elementof the city's general plan.

D. Provisions in the permit or license agreement shall specify the specific hour limitations imposed, and the set decibel level delineated in the noise element which would apply.

Applicable Vibration StandardsThe City of Pasadena does not have vibration standards. To assess the potential for vibration impacts, vibration thresholds found within the Federal Transit Administration's Transit (FTA) Noiseand Vibration Impact Assessment Manual (FTA 2018) were used in the assessment of potentialproject related vibration impacts.Noise Effects Noise impacts associated with the proposed Project would be largely limited to the construction phase. Construction equipment can be considered to operate in two modes: stationary andmobile. Stationary equipment operates in one location for one or more days at a time, with either a fixed-power operation (such as pumps, generators, and compressors) or a variable noiseoperation (such as rock drills and pavement breakers). For well drilling, stationary equipment(such as an auger, compressor, and circulation tank motors) would be used. Mobile equipment ismoved around the construction site and includes equipment (such as material delivery trucks, a gradall, and a backhoe). The primary noise sources during construction are the diesel engines ofconstruction equipment (such as drill auger motor, compressor, circulation tank motor, backhoe loader, gradall, and delivery trucks). No pile driving or blasting activities are proposed; however, well development requires a continuous process of drilling to prevent well collapse. As such, well drilling would occur for 24 hours per day/7 days per week for four (4) weeks with a pause of two(2) weeks for water quality analyses and final well design, and a continuation of well drilling for two and half (2.5) weeks. Well construction and development would continue for one and half 4-62 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
(1.5) weeks following well drilling activities and would also occur for 24 hours/7 days. As such,24 hour/7 day construction activities are anticipated to last for a total of approximately eight (8) weeks, as detailed in Table 15.

Explorer Well. The degree to which noise-sensitive receptors are affected by constructionactivities depends heavily on their proximity as well as the time of day or night. As stated above, per Section 9.36.080, Construction Equipment, of the City's Municipal Code, it is unlawful for any person to operate any powered construction equipment if the operation of such equipmentemits noise at a level in excess of 85 dBA when measured within a radius of 100 feet from suchequipment. Therefore, estimated noise levels attributable to the development of the proposed Project is evaluated at 100 feet from the equipment, as shown in Table 15, Construction NoiseLevels at Noise-Sensitive Land Uses. Noise calculations are included in Appendix D. As shownin Table 15, noise levels from construction equipment would be less than the 85 dBA noise limitas measured at 100 feet from the equipment, per the City's Municipal Code Section 9.36.080 -Construction Equipment.

TABLE 15

CONSTRUCTION NOISE LEVELS AT NOISE-SENSITIVE LAND USES
Construction Phase
Noise Level at 100
ft (Leq dBA)
City of Pasadena
Noise Limit Exceeds Limit?
Ground Clearing/Demolition 78 85 NoExcavation 83 85 No
Foundation Construction 72 85 NoBuilding Construction 81 85 NoPaving and Site Cleanup 83 85 NoL,q dBA: Average noise energy level; ft: feet.Note: Noise levels from construction activities do not take into account attenuation provided by intervening structures or soundbarriers.Source: USEPA 1971 a.

Noise from on-site construction activities would be audible above the existing ambient noise environment but would generally occur during the least noise-sensitive portions of the day as per Pasadena Municipal Code Section 9.36.070 - Construction Projects. As mentioned previously,nighttime drilling is necessary for well development. To quantify noise emission levels from the Project site due to nighttime well drilling activities, SoundPlan, a three-dimensional computational noise model, was used. This model considers topographical elevations and noise attenuationprovided by ground cover and structures. Noise data acquired from a similar well project4 wasutilized as the input dataset for the construction sources to the SoundPlan modeling for the well drilling activities of the Project. Well drilling noise is associated with the operation ofdiesel fueled motor for the auger, auger drilling activities, circulation tank motor for the drilled sediment,compressor, gradall used for carrying auger bit extensions, and a backhoe for the removal ofexcavated sediment. The Project site and nearby structures were modeled in three dimensions to allow for the heights of sound barriers used for noise attenuation to be considered.

Noise levels from Project-related nighttime well drilling activities at the nearest noise sensitive residential uses (i.e., residences located 195 feet east of the Project's site boundary) areestimated to be 54-56 dBA Leq without noise reducing mitigation measures. This noise exposure level was modeled at the property line of the nearest residential uses located up the hill to the east of the Project site. Building structures generally attenuate exterior noise levels by 20 to 254 Garfield Replacement Well Project, July 2021 4-63 Environmental Assessment
Explorer Well Project
Initial Study/M/t/gated Negative Declaration
dBA under a "windows-closed" condition (FHWA 2011). Without noise reducing mitigationmeasures, the noise reduction provided by the residential building structures, interior noise levelsare anticipated to be up to 34-36 dBA Leq at the nearest residential structures. The United States Environmental Protection Agency (USEPA) has referenced a sleep disturbance study that provides context on the levels of sleep disturbance expected from noise levels. This study states that there is a correlation between ranges of A-weighted sound level results and frequency of complaints by those who experience these sound levels. The study found the following: belowabout 33 decibels, no complaints; 33-38 decibels, occasional complaints; 38-48 decibels, frequent complaints; and over 48 decibels, unlimited complaints" (USEPA 1971 b). This level of noise that would result in sleep disturbance is also consistent with the recommendation from the World Health Organization (WHO) which states that "If negative effects on sleep are to be avoided the equivalent sound pressure level should not exceed 30 dBA indoors for continuous noise.

As mentioned previously, well drilling activities would result in an interior noise exposure level of up to 34-36 dBA Leq without noise reduction mitigation measures. This level of noise would exceed the 30 dBA Leq recommended interior noise exposure threshold for sleep disturbance at nearby residential uses. To minimize the potential for sleep disturbance from nighttime well drilling activities, the noise reduction measures detailed under MM N01-1 through MM NOI-4 are required to reduce noise to levels that are below the above-mentioned sleep disturbance thresholds.

MM N01-1 requires the Construction Contractor to implement best management practices for construction equipment during construction activities, including, but not limited to, ensuring thatall stationary and mobile construction equipment be equipped with properly operating and maintained mufflers (MM N01-1 a) and backup alarms for construction equipment be low-impact (MM NOI-1e).

MM N01-2 details sound barrier requirements for nighttime construction activity, such as 12-footsound enclosures on stationary equipment (MM N01-2a), and strategic placing of constructionequipment onsite (IV1M N01-2c). To assess noise levels from nighttime well drilling activities with MM N01-2a and MM N01-2b, an engine enclosure for the circulation tank motor was modeled within SoundPlan, respectively. As shown in Exhibits 4-2 through 4-5, well drilling activities with noise-reducing mitigation measures would result in a noise exposure level of up to 44-49 dBA Leqat the nearest residential facades. With the exterior to interior noise reduction provided byresidential building structures, interior noise levels is anticipated to be 20 to 25 dBA less and would result in an interior noise level of up to 24-29 dBA Leq. It should be noted that not all mitigation measures required for this Project were quantified in the SoundPlan analysis, thusproviding a conservative estimate of proposed noise levels. Based on the beforementioned guidance provided by the USEPA and WHO, interior noise levels of less than 30 dBA Leq are notanticipated to result in sleep disturbance at nearby residential uses. Additionally, MM N01-3 requires that an opportunity for communication between City staff and the surrounding communities regarding nighttime construction activities is provided.

Per MM N01-3, prior to commencement of nighttime Project construction, the City of Pasadena shall establish a designated phone hotline and email address for Project-related information andcomplaints from the surrounding neighborhood. Fliers and posters shall be posted and visible at the Project boundary at least one week prior to commencement of nighttime construction activity and be visible throughout the nighttime construction duration. Also, MM N01-4 requires that theCity retain a Noise Monitor for on-call services to ensure that nighttime construction noise does not exceed 50 dBA Leq at the nearest residential fa?ade proximate to the site during nighttime construction activities. A 50 dBA Leq exterior exposure level would be reduced by at least 20-25dBA due to the building facade and result in interior noise levels of 30 dBA or less which is below the USEPA's sleep disturbance level. As such, most people with typical noise sensitivities at nearby residential uses closest to the Project site are not anticipated to experience sleep 4-64 Environmental Assessment
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Source: Psomas, 2023
Noise Modeling Results for Nighttime Drilling with No Noise Protection Exhibit 4-2 Explorer Well Project
N -^.

Map not to scale (11/07/2023 PLO)R:\Projects\PAS_Pasaden\3PAS013201" Explorer Wel)\Graphics\HM\ex_NoProtection.pctf i
II
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s ^ •.- av Nighttime Drilling Noise
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Source: Psomas, 2023
Noise Modeling Levels for Nighttime Drilling with No Noise Protection Exhibit 4-3Explorer Well Project -^
Map not to scale (11/07/2023 PLO) R:\ProJects\PAS_Pasaden\3PAS013201 - Exp<orer We))\Graphics\NM\ex_NoProtection_Contours.pdf II
IIfl
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1:.;*,.-'-/'' <>.';-.^¥.^' <!:-', 1"'^':-.'^^^ .'•.•Lfc';-.,' v^ 31 9 Nighttime Drilling Noise With Noise Protection .•• c 40.4 V ? K •^
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Source; Psomas, 2023
Noise Modeling Results for Nighttime Drilling with Noise Protection Exhibit 4-4 Explorer Well Project
-^
Map not to scale (11/07/2023 PLO)R:\ProJects\PAS_Pasaden\3PAS013201 - Explorer Well\Graphics\NM\ex^WithProtection.pdf II
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Source: Psomas, 2023
Noise Modeling Levels for Nighttime Drilling with Noise Protection Exhibit 4-5 Explorer Well Project
Map not to scale (11/07/2023 PLO)R:\Projects\PAS_Pasaden\3PAS013201-Explorer WellVGraphics\NM\ex_WithProtection_Contours.pdf Explorer Well Project
Initial Study/Mitigated Negative Declaration
disturbance from on-site Project-related construction activities under mitigated conditions.

Residential uses located further from the Project site are exposed to less noise and would likewise not experience sleep disturbance from the Project's mitigated construction activities. Impacts fromon-site construction during nights and early mornings would thereby be less than significant with mitigation.

The Project would generate construction traffic noise from vehicle traffic, including workerscommuting to and from the Project site, vendors delivering materials, and haul trucks exportingwell drilling spoils and liquid storage tanks. Truck (i.e., heavy truck) pass-by trips would be heard at residences adjacent to the roads used, which would include WindsorAvenue, from the l-210toExplorer Road and into the Project site. The maximum number of heavy truck trips is anticipated to be thirty truck trips over a one-month period. This quantity amounts to approximately 1-2 truck trips per day. Additionally, MM N01-1 d limits truck trips to export drill cuttings to the daytime when people are less sensitive to noise. It is anticipated that an average of approximately three workers would be onsite at the same time, which would generate an average of approximately six construction-related worker commute trips per day. Due to the infrequency of Project-related truckand worker commute trips, the increase in traffic noise would be less than the 3 dBA significance threshold for noise (Caltrans 201 3). A 3 dBA increase is the minimum change in noise levels that is audible in outdoor environments. A doubling of traffic along local roadways is necessary for a 3dBA change in noise levels. Consequently, construction-related traffic noise impacts would be temporary, but not substantial.

As discussed previously, the noise generated during construction would not involve pile drivers orother equipment that would exceed the 85 dBA noise level limit as measured at 100 feetestablished by the City under Pasadena Municipal Code Section 9.36.080. As such, the Project would not result in substantial temporary noise impacts and sleep disturbance to residential land uses nearby the Project site. Thus, noise associated with Project-related construction activities would comply with Pasadena Municipal Code Sections 9.36.050, General Noise and be belowthe sleep disturbance thresholds, and thus, less than significant impacts would result with implementation of MMs N01-1 through MM NOI-4.

The Project's proposed 800 feet of new raw water pipeline within Karl Johnson Parkway would require the demolition of existing asphalt, trenching, pipe installation, and well site pipingconnections. Construction activities would be located as close as 200 feet from nearby residentialuses. The estimated noise level at the closest homes along Ridgeview Drive in Altadena, which would occur intermittently, is calculated at 73 dBA which is less than the County standard of 75 dBA Leq. This noise level is also less than the limit of 85 dBA at 100 feet stated in Section 9.36.080 of the City of Pasadena Noise Ordinance. As such, noise from construction activities associated with the pipelines would be less than significant. All pipeline construction activities would also be limited to between the hours of 7:00 AM and 7:00 PM Monday through Friday and between 8:00 AM and 5:00 PM on Saturday, as required by the City's Noise Ordinance. Although no mitigation is required, MM N01-1 would be implemented for all phases of the Project.

The operating conditions of the Project would involve a pump for groundwater extraction andtransference, which would generate noise that is contained within an enclosed building to attenuate noise. The building would be constructed of concrete-masonry units. MM N01-5 would ensure that the Project is compliant with applicable noise standards through a post-construction noise survey and applying any necessary noise reduction measures to ensure compliance.

In summary, with implementation of MMs N01-1 through MM NOI-5, the Project would have a less than significant impact related to this threshold. 4-65 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
b) Would the project result in generation of excessive groundborne vibration or groundborne noise levels?
No Impact. As stated above, there are no applicable City of Pasadena standards for vibration-induced annoyance or building damage from vibration. Potential vibration impacts are assessed based on thresholds recommended by the FTA. The FTA recommends a construction vibration damage criteria of 0.2 peak particle velocity (ppv) for non-engineered timber and masonry buildings. This is representative of the residential and nonresidential structures closest to the Project site. Construction equipment utilized during Project development would producevibration from vehicle travel as well as demolition, grading, and building construction activities.The development of the Project facilities would generally occur at a distance of 200 feet from construction equipment to the nearest residential structures. Table 16, Vibration Criteria atNearest Sensitive Uses, shows the vibration levels relative to building damage to sensitive uses from vibration activities. As shown in Table 16, all ppv levels would be below the vibrationthreshold at the nearest off-site structures.

TABLE 16

VIBRATION CRITERIA AT NEAREST SENSITIVE USES
Equipment
Vibration Levels (ppv)
Residences to the
East
Altadena
Staples
Odyssey
Charter School
Sacred Heart
Catholic Church
(ppv@195ft) (ppv@580ft) | (ppv@ 1,230 ft) | (ppv@2,130ft) Vibratory Roller 0.010 0.002 0.001 0.000Caisson Drill 0.004 0.001 0.000 0.000Large bulldozer 0.004 0.001 0.000 0.000Small bulldozer 0.000 0.000 0.000 0.000Jackhammer 0.002 0.000 0.000 0.000Loaded trucks 0.003 0.001 0.000 0.000 Vibration Criteria* 0.2 0.2 0.2 0.2
Exceeds Criteria? No No No No
ppv: peak particle velocity; ft: feet.* Federal Transit Administration. Table 7-5 Construction Vibration Damage Criteria..

These vibration levels represent conditions when construction activities occur closest to receptor locations. Because vibration levels would be substantially below the significance threshold, vibration generated by the Project's construction equipment would result in less than significant vibration impacts, and no mitigation is required.When the Project begins operations, the Project-related equipment would not generatesubstantial levels of vibration that would be detectable at nearby residential land uses. As such, the Project would result in less than significant vibration impacts during operation of the Project, and no mitigation is required.c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in theproject area to excessive noise levels? No Impact. There are no airports or airstrips within two miles of the Project site. The nearest airports are the Burbank Bob Hope Airport and the El Monte Airport, which are both approximately 4-66 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
11 miles from the site. The Project would not subject persons in the area to excessive levels of noise exposure from public or private airports, nor would the Project generate aircraft noise. There would be no significant impact from the exposure of aircraft noise to maintenance workers relatedto the Project.

MITIGATION MEASURES
MM N01-1 The Construction Contractor shall implement the following noise reduction measures during all construction activities:
a. All stationary or mobile construction equipment shall be equipped with properly-operating and maintained mufflers and engine enclosures,compliant with or exceeding manufacturers' standards. b. All construction equipment engine enclosures and covers, as provided by manufacturers, shall be in place during construction activities. c. All construction equipment shall be shut down when not in use.

Construction equipment shall not be allowed to idle for more than 3 minutes.
d. During Project construction, export of drill cuttings via trucks shall be limited to the hours of 7 AM through 7 PM.
e. For nighttime activities, construction-standard high-pitch backup alarms for construction equipment and vehicles shall not be used during construction of the Project. Construction equipment and vehicles shall use low-impact backup alarms, including, but not limited to, the following:manually-adjustable alarms, self-adjusting alarms, and broadband (white noise) alarms. These alarms shall conform to the safety requirements established by the Occupational Safety and Health Administration (OShHA).

MM N01-2 During nighttime construction activity (i.e., from 7 PM to 7 AM), the Construction Contractor shall ensure that the following best management practices for soundbarriers are implemented:
a. Sound barrier enclosures of a minimum height of 12 feet shall enclose all stationary equipment sources of noise on four sides. These enclosuresshall be constructed of either 3/4-inch plywood or greater thickness or soundblankets with a minimum sound transmission class (STC) rating of 25 and cover all sides as well as the top of the equipment. Minimal gaps in theenclosure are acceptable to ensure adequate air intake, exhaustventilation, and heat dissipation for proper equipment functioning. b. Temporary sediment settling tanks (i.e., Baker tanks) shall be strategically placed between the circulation tank motor and the nearest residential use.

Fliers or posters must be posted and visible at the Project boundary at least one week prior to commencement of nighttime construction activity and continuethroughout the nighttime construction duration. These posters must provide the 4-67 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
following information: nighttime construction duration and other related details and contact information for the phone hotline and email address.

MM N01-4 Prior to commencement of nighttime construction activities, the City shall retain a Noise Monitor to monitor noise levels during nighttime construction activities (i.e., from 7 PM to 7 AM). The Noise Monitor shall monitor and record noise at the property line for the nearest residential uses (west and east of the Project site) toensure that noise levels from the Project construction site do not exceed 50 A-weighted decibels (dBA) at night. If Project-related noise levels exceed 50 dBA during nighttime activities, additional noise reduction measures shall beimplemented to further reduce construction noise at the Project site to a level at orbelow 50 dBA, such as additional vertical and horizontal sound barriers.

MM N01-5 Once the Project is operational, the City of Pasadena shall conduct a post-construction noise survey to ensure the operation of the well equipment iscompliant with the City's noise ordinances. 4-68 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.14 POPULAJ-ION AND HOUSING Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Less
Than
Significan No
t Impact Impact
Would the project:
a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing newhomes and businesses) or indirectly (for example, through extension of roads or other infrastructure)?
b) Displace substantial numbers of existing people or
housing, necessitating the construction of replacementhousing elsewhere? DD
D
D
^a
Ds

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to population and housing.

Impact Discussion
a) Would the project induce substantial unplanned population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)? Less Than Significant Impact. The Project consists of a new building containing a new groundwater well, as well as a new segment of pipeline.

Given that the Project proposes no new homes or businesses, the Project would not result in anydirect unplanned population growth.The proposed groundwater well and new pipeline that are proposed as part of the Project would not result in indirect unplanned population growth given that all groundwater extraction conductedby PWP is limited by its groundwater rights in the Raymond Basin. Although the Project wouldincrease the City's capacity for pumping, the amount of water pumped remains limited by theRaymond Basin Judgment. Since the Project does not increase the supply of water to the City, it does not indirectly induce growth.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.b) Would the project displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?? No Impact. The Project would not require the displacement of any residents or removal of anyhousing. As such, the Project would not necessitate the construction of replacement housing elsewhere.Therefore, the Project would result in no impact related to this threshold, and no mitigation is required.
4-69 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

MITIGATION MEASURES
No significant impacts pertaining to population and housing were identified; therefore, no mitigation measures are required.
4-70 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.15 PUBLIC SERVICES Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered government facilities, need for new or physicallyaltered government facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times, orother performance objectives for any of the publicservices:Fire protection? Police protection?
Schools?
Parks?Other public facilities?
aDDDD
DDDDD
^^aDa
DDs^^

IMPACT ANALYSIS
Regulatory RequirementsRR PS-1 The Project shall be designed and constructed in accordance with the Pasadena Fire Prevention Code (Chapter 14.28 of the City's Municipal Code), which adopts the California Fire Code with changes and additions to the adopted code.

Impact Discussion
a) Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered government facilities, need for new or physically altered government facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times, or other performance objectives for any of the public services:

Fire protection?Police protection?
Schools?Parks?
• Other public facilities?
Fire ProtectionLess Than Significant Impact. The Project would not increase the population within the Projectsite since the Project consists of a well and pipeline. The proposed building would result in a minor increase in demand for fire protection services, particularly response to fire service calls if neededonce the Project is built. This minor increase in demand for fire protection services is not expected to require the construction of new or alteration of existing fire protection facilities to maintain an adequate level of fire protection service to the Project area. 4-71 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
The building that would be built as part of the Project would be designed consistent with the Uniform Building Code and the California Fire Code, which requires implementation of design standards and requirements to reduce potential fire risk. Also, the Project would be constructed in accordance with the Pasadena Fire Prevention Code (Chapter 14.28 of the City's Municipal Code) as described in RR PS-1. Compliance with codes would minimize the potential for fire toaffect the Project's proposed well building and, therefore, the Project's demand for fire protectionservices.Therefore, the Project would result in a less than significant impact related to fire protectionservices, and no mitigation is required.Police ProtectionLess Than Significant Impact. Construction of the Project would temporarily provideopportunities for crime (e.g., theft and vandalism). However, construction areas and staging areas would be screened/fenced, which would prevent theft and vandalism during the construction phase.

The Project would result in a new building that would require police protection; however, the area is already patrolled by the police and would therefore not substantially increase demand for police service. The proposed well and pipelines are not likely land uses that would attract criminalactivities. A chain-link fence would be constructed around the well site enclosing the well buildingand transformer, which would further prevent crime and the need for police protection services.

Therefore, the Project would result in a less than significant impact related to police protection services, and no mitigation is required.SchoolsNo Impact. The Project consists of a well and pipeline and would therefore not result in any new students nor would the Project otherwise generate demand for school services.Therefore, the Project would have no impact related to schools, and no mitigation is required.ParksNo Impact. The Project consists of a well and pipeline and would therefore not result in any newresidents that would require parks or other recreational facilities.Therefore, the Project would have no impact related to this threshold, and no mitigation is required.

Other Public Facilities
No Impact. The Project consists of a well and pipeline and would therefore not result in any newresidents that would require libraries or other public facilities.

Therefore, the Project would have no impact related to other public facilities, such as libraries,and no mitigation is required. 4-72 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

MITIGATION MEASURES
No significant impacts pertaining to public services were identified; therefore, no mitigationmeasures are required. 4-73 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.16 RECREATION
Less Than
Potentially Significant Less Than
Significant with Significant No
Impact Mitigation Impact Impact
Would/does the project:a) Would the project increase the use of existing neighborhood and regional parks or other recreational
facilities such that substantial physical deterioration ofthe facility would occur or be accelerated? b) Does the project include recreational facilities or require the construction or expansion of recreational facilitieswhich might have an adverse physical effect on theenvironment? aD
n
a
aa
s
s

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to recreation.

Impact Discussion
a) Would the project increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?
b) Does the project include recreational facilities or require the construction or expansion of recreational facilities which might have an adverse physical effect onthe environment? No Impact. The Project consists of a well and pipeline and would therefore not result in any newresidents that would require parks or other recreational facilities.

Therefore, the Project would have no impact related to these thresholds, and no mitigation isrequired.

MITIGATION MEASURES
No significant impacts pert:aining to recreation were identified; therefore, no mitigation measures are required.
4-74 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration

4.17 TRANSPORTATION
Less Than
Potentially Significant Less Than
Significant With Significant No
Impact Mitigation Impact Impact
Would the project:
a) Conflict with a program, plan, ordinance or policy
addressing the circulation system, including transit,
roadway, bicycle and pedestrian facilities?
b) Conflict or be inconsistent with CEQA Guidelines §
15064.3, subdivision (b)?
c) Substantially increase hazards due to a geometric
design feature (e.g., sharp curves or dangerousintersections) or incompatible uses (e.g., farmequipment)? d) Result in inadequate emergency access?
D
DDD
D
DDD
s
ss^
a
DDD

IMPACT ANALYSIS
Regulatory RequirementsRRTRA-1 Construction activities will be conducted in accordance with the Standard Specifications for Public Works Construction (Greenbook) and the City'sSupplements and Modifications to the Greenbook to maintain access to all parcelsin and near the construction sites. This includes notification of residents andbusinesses affected by the road work; utility agencies with facilities in the area; the Pasadena Fire and Police Departments; and other emergency service providers.

The Greenbook also requires that access be made available at the end of eachworkday.

RRTRA-2 Temporary traffic control devices and methods used during construction are required to conform to the requirements of the latest edition of the Manual onUniform Traffic Control Devices (MUTCD) and the California Supplement to theMUTCD. The contractor shall provide traffic tapers, traffic control devices, barricading, and signs necessary to ensure driver awareness and safety inconstruction areas and to assist fire and law enforcement personnel.

Impact Discussiona) Would the project conflict with a program, plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities? Less Than Significant Impact. Pasadena developed and adopted its Transportation Impact Analysis Current Practice and Guidelines (TIA Guidelines) to ensure that transportation system improvements necessary to support new development while maintaining the quality of life within the community are identified prior to project approval and funded prior to construction. As the CEQA Lead Agency, Pasadena's transportation guidelines apply to the Project. Pursuant to SB743, Pasadena TIA Guidelines establish CEQA transportation analysis metrics including: VMTperCapita, vehicle trips per Capita, Proximity and Quality of the Bicycle and Transit Networks, and Pedestrian Accessibility (Pasadena 2022).
4-75 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
Per the Pasadena TIA Guidelines, a CEQA transportation analysis shall be conducted for development projects which satisfy any of the following conditions: (1) proposes 50 or more netnew residential dwelling units, or (2) project proposes 50,000 or more net new non-residentialsquare feet (Pasadena 2022). The Project is not a development project and does not meet anyconditions requiring a full traffic analysis for long-term operation. Therefore, a TIA is not warranted for the Project.The Project consists of a well and a pipeline, neither of which have the potential to conflict with any programs, plans, ordinances, or policies relating to the circulation system. Access to trailsand along Explorer Road would be maintained throughout Project construction to the maximumextent feasible, with only minor temporary detours during the realignment of Explorer Road.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.b) Would the project conflict or be inconsistent with CEQA Guidelines § 15064.3, subdivision (b)?
Less Than Significant Impact. Section 15064.3(b)(1) of the State CEQA Guidelines refers toevaluating transportation impacts using vehicle miles traveled for land use projects.

The Project consists of a well and pipeline that have no potential to measurably increase the City'sVMT/capita. VMT would be generated during construction associated with vehicle trips to/fromthe Project site and from construction equipment usage on the Project site. However, this would be a minor amount of VMT and would end once the Project is built. During operation, a limitednumber of vehicle trips per week would be generated for inspection and maintenance purposes.However, such amount of trips is well below the thresholds for requiring a VMT analysis or anyother type of transportation review, per the City's Transportation Impact Analysis Guidelines, which specify that non-residential land uses that generate less than 110 net new daily trips areexempt from transportation review.Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
c) Would the project substantially increase hazards due to a design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?
Less Than Significant Impact. A 400-foot segment of Explorer Road would be permanentlyrealigned as part of the Project. The realigned segment of Explorer Road would be similar to the existing roadway once re-built except that the road would be aligned approximately ten feet to thewest. This minor realignment would create new curves in the road that do not currently exist; however, these curves would not be sharp, and signage would be provided so that users ofExplorer Road will be able to navigate the turns. Furthermore, the curves proposed are similar tocurves in the road that exist to the south of the Project site.

New driveways would be provided at two locations within the Project site that would connect to the realigned Explorer Road. These driveways have been designed to allow for adequate sightdistance for vehicles entering and leaving the Explorer Well property. Also, these driveways have been designed to include clear demarcations such as striping and signage to minimize potentialconflict with users on Explorer Road. 4-76 Environmental Assessment
Explorer Well Project
Initial Study/Mitigated Negative Declaration
During construction of the realigned Explorer Road, access to JPL's east gate would be restricted for approximately one week while a section of Explorer Road is realigned. Any closures would be coordinated with JPL prior to implementation. Construction of the road realignment would allow for through traffic to continue to utilize Explorer Road white the well is constructed. In addition, designated staging areas would be fenced to prevent safety hazards. As such, the proposed well would not pose a roadway design hazard or impediment.

The proposed pipeline would be constructed underground within the Karl Johnson Parkway and Explorer Road. During pipeline installation, sections of Karl John Parkway will be closed off to vehicle and pedestrian traffic. The pipeline installation would not result in roadway design hazards, as it is not a public-access roadway and since the roadway would be re-paved and returned topre-Project conditions after construction is complete.During construction, the Project would adhere to RR TRA-1, which mandates that construction activities are conducted in accordance with the Standard Specifications for Public WorksConstruction (Greenbook) and the City's Supplements and Modifications to the Greenbook.TheGreenbook also requires that access be made available at the end of each workday.

Implementation of RR TRA-1 would ensure that there would not be increased hazards for any users of the road.

A minor increase in the number of construction vehicles and trucks on Windsor Avenue during Project implementation would increase opportunities for traffic hazards. Flagpersons, signs, and traffic control devices would be provided as needed by the Contractor in accordance with the Greenbook (RR TRA-1) and MUTCD (RR TRA-2) to prevent hazards associated with construction vehicles.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
d) Would the project result in inadequate emergency access? Less Than Significant Impact. Construction worker vehicles, trucks, delivery vehicles, and haul trucks would access the site via l-210 at the Windsor Avenue off-ramp and head north on Explorer Road to reach the Project site. All construction staging and parking would occur on the Project site. Construction activities associated with the Project would not result in obstruction of Explorer Road, which provides emergency access. Additionally, the Project would comply with theStandard Specifications for Public Works Construction (Greenbook) and the City's Supplements and Modifications to the Greenbook (RR TRA-1) regarding maintenance of emergency access atall times; the use of a flagperson to direct traffic, as necessary; and allowing for the continued public use of the Explorer Road at times when construction is not ongoing. Temporary traffic control devices are also required to be provided in conformance with the MUTCD and the California Supplement to the MUTCD (RR TRA-2).

Therefore, the Project would result in a less than significant related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to transportation were identified; therefore, no mitigationmeasures are required. 4-77 Environmental Assessment
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4.18 TRIBAL CULTURAL RESOURCES Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Cause a substantial adverse change in the
significance of a tribal cultural resource, defined in
Public Resources Code § 21074 as either a site,
feature, place, cultural landscape that isgeographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that
is:
i) Listed or eligible for listing in the California
Register of Historical Resources, or in a localregister of historical resources as defined inPublic Resources Code section 5020.1(k), or ii) A resource determined by the lead agency, in its
discretion and supported by substantial evidence,to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code §5024.1. In applying the criteria set forth in subdivision (c) of Public Resource Code §
5024.1, the lead agency shall consider the
significance of the resource to a California NativeAmerican tribe? aD
s^
D
a
Da

IMPACT ANALYSIS
Regulatory RequirementsRegulatory requirements related to tribal cultural resources have been incorporated intoMM TCR-3, which is discussed below.Impact Discussion a) Would the project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code § 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a CaliforniaNative American tribe, and that is:
i) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code section 5020.1 (k), or
ii) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth insubdivision (c) of Public Resources Code Section 5024.1. In applying the criteriaset forth in subdivision (c) of Public Resource Code Section 5024.1, the leadagency shall consider the significance of the resource to a California Native American tribe?
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Less Than Significant With Mitigation. The Project is subject to compliance with AB 52, which requires consideration of impacts to "tribal cultural resources" (TCRs), defined in Section 21074 of the Public Resources Code, as part of the CEQA process. AB 52 requires the City to notify anygroups (who have requested notification) who are traditionally or culturally affiliated with thegeographic area of a project for which a negative declaration, an MND, or an EIR is required pursuant to CEQA. The Tribes are provided 30 days to request consultation after the lead agencynotifies the tribe of a project.

The City initiated the AB 52 process in September 2023 by sending notifications to tribes on the City's AB 52 contact list. The City conducted AB 52 tribal consultation with the one responding tribe, Gabrieleno Band of Mission Indians- Kizh Nation. During tribal consultation, no information was provided indicating the presence of any known tribal cultural resources within the Project site. hlowever, due to the potential for unknown tribal cultural resources to be encountered during ground disturbance activities that would occur during construction, the Gabrieleno Band of Mission Indians - Kizh Nation requested that measures be implemented to avoid and minimizepotential impacts. The Project would implement MM TCR-1, which requires that a Native American Monitor be retained prior to commencement of ground disturbing activities, and whichestablishes monitoring requirements. MM TCR-2 would also be implemented, which establishesthe protocols to be followed in the event that unanticipated discoveries of tribal cultural resource objects occur. Finally, MM TCR-3 would also be implemented by the Project, which establishes the protocols if human remains, grave goods, and/or historical archaeological materials are encountered.

With implementation of MM TCR-1, MM TCR-2, and MM TCR-3, the Project would result in a lessthan significant impact related to these thresholds.

MITIGATION MEASURES
TCR-1 Retain a Native American Monitor Prior to Commencement of Ground Disturbing Activities: Prior to commencement ofground-disturbing activities, theCity of Pasadena (City) shall retain a Native American Monitor (NAM) from orapproved by the Gabrieleno Band of Mission Indians - Kizh Nation (the "Tribe" or"Kizh") to observe ground-disturbing activities, which may include, but are notlimited to, pavement removal, pot-holing or augering, grubbing, tree removals,boring, grading, excavation, drilling, and trenching, within the Project site.

Monitoring by the NAM is only to occur onsite when well drilling is scheduled within 50 feet below the ground surface (bgs) and is not to exceed five consecutive working days. The NAM shall complete daily monitoring logs providing descriptions of the day's activities including construction activities, locations, soil, and anycultural materials identified. All discovered tribal cultural resources found during ground-disturbing activities for the Project within 50 feet bgs, shall be temporarilycurated in a secure location on site by the Project Archaeologist (refer to MM-CUL1). If removal of artifacts from the Project site is necessary, each artifact shall be catalogued by the Project Archaeologist, and an inventory will be provided to theNAM upon each addition.

Additionally, a tribal cultural specialist from the Kizh Nation will assess thesignificance of any Tribal Cultural Resource (TCR) under Assembly Bill 52 of theCalifornia Environmental Quality Act (CEQA). While there is significant overlap between archaeological resources and Tribal Cultural Resource, they are differentprotected resources under CEQA. Provenience is important for determining "significance" for an archaeological resource in order to establish whether it meets the California Register of Historical Resources eligibility criteria, however the same 4-79 Environmental Assessment
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is not true for TCRs. The objects, features, sites, sacred spaces, and landscapesare cosmologically considered living things and are considered significant to thedescendants of those People that left them behind. Therefore, both levels of significance assessments shall be made by both an archaeologist and the Kizh tribal monitor.

Following the completion of the Project, all tribal cultural resources shall bereturned to the Tribe. Following a discovery, at the completion of all grounddisturbing activities, the Project Archaeologist shall formulate a Monitoring Report(refer to MM CUL-1) and submit said report to the City of Pasadena and the SouthCentral Coastal Information Center (SCCIC) located at California State University,Fullerton and the Gabrieleno Band of Mission Indians-Kizh Nation Tribal Government. The report will document all monitoring efforts and involvement ofthe NAM. The report shall be completed within 60 days of conclusion of all Projectground-disturbing activities. The disposition of the resources shall be subject to review and approval by the City. If tribal cultural resources are discovered, workmay proceed in other areas of the site, subject to the direction of the Project Archaeologist or NAM.

MM TCR-2 Unanticipated Discovery of Tribal Cultural Resource Objects (NonFunerary/Non-Ceremonial): Upon discovery of a tribal cultural resource within the Project site during Project construction, all construction activities shall cease in the immediate vicinity of the discovery (not less than the surrounding 50 feet) and shall not resume until the find can be assessed. All tribal cultural resources unearthed by Project activities shall be evaluated by the Project Archaeologist and the NAM. If the resources are Native American in origin, the consulting tribe will retain it/them in the form and/or manner the tribe deems appropriate, for educational, cultural, and/or historic purposes.

MM TCR-3 Unanticipated Discovery of Native American Human Remains and Associated Funerary or Ceremonial Objects: If human remains and/or grave goods are discovered or recognized at the project sites, all ground disturbanceshall immediately cease, and the county coroner shall be notified per Public Resources Code Section 5097.98, and Health & Safety Code Section 7050.5.

Human remains and grave/burial goods shall be treated alike per California PublicResources Code section 5097.98(d)(1) and (2). Work may continue in other parts of the project sites while evaluation and, if necessary, mitigation takes place (CEQAGuidelines Section 15064.5[f]). Preservation in place (i.e., avoidance) is the preferred manner of treatment for human remains and/or burial goods. Ifpreservation in place is not feasible, treatment may include implementation ofarchaeological data recovery excavations to remove the resource along withsubsequent laboratory processing and analysis. Any discovery of humanremains/burial goods that are Native American in origin shall be kept confidential to prevent further disturbance.
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4.19 UTILITIES AND SERVICE SYSTEMS Potentially Significant Impact
Less Than
Significant
with
IVIitigation
Less Than
Significant No
Impact Impact
Would the project:
a) Require or result in the relocation or construction of new or expanded water, wastewater treatment or storm waterdrainage, electric power, natural gas, ortelecommunications facilities, the construction or relocation of which could cause significant environmental effects?
b) Have sufficient water supplies available to serve the project and reasonably foreseeable future developmentduring normal, dry and multiple dry years? c) Result in a determination by the waste water treatment provider, which serves or may serve the project that ithas adequate capacity to serve the project's projected demand in addition to the provider's existing
commitments?
d) Generate solid waste in excess of state or local
standards, or in excess of the capacity of local
infrastructure, or otherwise impair the attainment of solid waste reduction goals?
e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste? Da
a
D
D
D
a
DD
D
^s
^s
s
Da
DD
D

IMPACT ANALYSIS
Regulatory Requirements
RR UTIL-1 The Contractor is required to comply with the City's Construction and Demolition Waste Management Ordinance (Chapter 8.62 of the Pasadena Municipal Code),which requires preparation and implementation of a Waste Management Plan that shows how at least 75 percent of construction and demolition debris would be diverted away from landfills. The Waste Management Plan is subject to Cityapproval prior to the start of construction activities, and the Contractor shall provide monthly reports to demonstrate compliance during the construction phase.

Impact Discussion
a) Would the project require or result in the relocation or construction of new or expanded water, wastewater treatment or storm water drainage, electric power,natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects?
Less Than Significant Impact. The Project would involve new connections to existing electrical and water service lines, which would connect to the building containing the Explorer Well. The Project's demands for electricity would be minimal as described in more detail in Section 4.6,Energy. Also, the Project's demands for potable water would similarly be minimal. Therefore, theProject would not require the relocation or construction of any new or expanded utility systems. 4-81 Environmental Assessment
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The Project would have a less than significant impact related to this threshold, and no mitigation is required.
b) Would the project have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry and multiple dry years?
Less Than Significant Impact. The Project would connect to existing potable water service line;however, the Project's demand for potable water would be minimal once built. PWP ensures sufficient water supplies through their implementation of their 2020 UWMP (PWP 2021).Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.
c) Would the project result in a determination by the waste water treatment provider, which serves or may serve the project that it has adequate capacity to serve the project's projected demand in addition to the provider's existing commitments? Less Than Significant Impact. As discussed under Threshold 4.19(a) above, the Project wouldnot generate wastewater during operations. Construction activities would generate a minor amount of wastewater from portable toilets, which would be provided temporarily at the Projectsite for the construction crew. This nominal amount ofwastewater would be disposed of off-site.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.d) Would the project generate solid waste in excess of state or local standards, or in excess of the capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction goals?
Less Than Significant Impact. Construction activities would generate solid wastes, primarily composed of demolition debris (e.g., asphalt, building materials) and soils/sediment. Projectconstruction and demolition debris and soil to be exported would be disposed of at Scholl Canyon Landfill, located approximately eight driving miles from the site, at 3001 Scholl Canyon Road in Glendale. Consistent with the City's Construction and Demolition Waste Management Ordinance(Section 8.62 et. seq. of the PMC), a minimum of 75 percent of the construction and demolition debris generated during construction would be diverted through recycling or reuse (RR UTIL-1).Therefore, implementation of the Project would result in a nominal construction waste stream requiring landfill disposal. Operation of the Project would not generate any solid waste.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
e) Would the project comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
Less Than Significant lmpact.As discussed under Threshold 2.19(d) above, the Project wouldbe subject to and would comply with the City's C&D ordinance. The Project's minor amount of construction waste would not interfere with the City's attainment of its waste management goalspursuant toAB 939, the California Integrated Waste Management Act. As such, the Project wouldcomply with federal, State, and local regulations related to solid waste. 4-82 Environmental Assessment
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Therefore, the Project would have a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to utilities and service systems were identified; therefore, nomitigation measures are required. 4-83 Environmental Assessment
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4.20 WILDFIRE Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
If located in or near State Responsibility Areas or lands classified as Very High Fire Hazard Severity Zones, would the project:
a. Substantially impair an adopted emergency response
plan or emergency evacuation plan?
b. Due to slope, prevailing winds, and other factors,
exacerbate wildfire risks, and thereby expose project
occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
c. Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency
water sources, power lines or other utilities) that mayexacerbate fire risk or that may result in temporary orongoing impacts to the environment? d) Expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a
result of runoff, post-fire slope instability, or drainage changes?
aD
aa
DD
aa
Bs
s
DD
aD

IMPACT ANALYSIS
Regulatory Requirements
There are no regulatory requirements applicable to wildfire.

Impact Discussion
a) Would the project substantially impair an adopted emergency response plan or emergency evacuation plan?
Less Than Significant Impact The Project site is located within a Fire Hazard Severity Zone in an LRA (CAL FIRE 2023). According to mapping prepared by the Pasadena Fire Department, the northern portion of the Project site is within an area that is designated as a VHFHSZ (City of Pasadena 2023b).

The Project would not directly affect any City or County emergency evacuation routes, such as 1-210 and Woodbury Road (Los Angeles County 2023). The Project would result in additional traffic temporarily on these roadways during construction; however, the number of trips during construction would be minimal when compared to the capacity of these roads.Otherwise, there are no City or County emergency response or evacuation plans that are directlyapplicable to the Project or to the Project site.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.
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b) Would the project due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrationsfrom a wildfire or the uncontrolled spread of a wildfire? Less Than Significant Impact. There would be no long-term occupants associated with the Project as the Project involves the construction and operation of a well and pipeline. Temporarily during construction there would be construction crews on the Project site who could potentially be affected by wildfire; however, impacts would be minimized as construction staff would evacuate the Project site in such an event.

Therefore, the Project would result in a less than significant impact related to this threshold, andno mitigation is required.c) Would the project require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment?
Less Than Significant Impact. The Project would not involve any infrastructure outside of theProject site. The Project's ongoing maintenance would not involve any activities that would in any way exacerbate fire risks or that would otherwise result in environmental impacts.Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.d) Would the project expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a result of runoff, post-fire slope instability, or drainage changes?
Less Than Significant Impact. The Project would not involve construction or operation ofhabitable structures; therefore, the Project would not expose people to wildfire or post-wildfirehazards. The proposed well and building would be built outside of the floodplain and would not be at-risk of flooding. All project components would comply with the City's Floodplain ManagementRegulations Ordinance (Chapter 14.27 of the Pasadena Municipal Code), which requires facilities to be adequately anchored to prevent flotation, collapse, or lateral movement; to be constructedwith materials and equipment resistant to flood damage; to have utility and service facilities designed and located to prevent water from entering; and to provide adequate drainage to reduceexposure to flood hazards. The Project's proposed structures would also be designed andconstructed in accordance with the City's Building Code and the recommendations of the Project'sGeotechnical Report which would ensure construction would avoid activities associated withlandslide and soil instability.

Therefore, the Project would result in a less than significant impact related to this threshold, and no mitigation is required.

MITIGATION MEASURES
No significant impacts pertaining to wildfire were identified; therefore, no mitigation measures arerequired. 4-85 Environmental Assessment
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4.21 MANDATORY FINDINGS OF
SIGNIFICANCE Potentially Significant
Impact
Less Than
Significant
with
Mitigation
Less Than
Significant No
Impact Impact
Does the project:
a. Does the project have the potential to substantially degrade the quality of the environment, substantially
reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self sustaining levels, threaten to eliminate a plant or animal community, substantially reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or
prehistory?
b. Does the project have impacts that are individually
limited, but cumulatively considerable? ("Cumulatively
considerable" means that the incremental effects of a
project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects)? c. Does the project have environmental effects which will cause substantial adverse effects on human beings,either directly or indirectly? D s a a
aa
Ds
sD
D
a

MANDATORY FINDINGS OF SIGNIFICANCE ANALYSIS
a) Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of rare or endangered plant or animal, or eliminate important examples of the major periods of Californiahistory or prehistory? Less Than Significant With Mitigation. The Project would result in significant impacts related to biological resources, cultural resources, geology and soils, and tribal cultural resources prior tothe implementation of mitigation. Regarding biological resources, the Project has the potential to result in significant impacts related to one special status wildlife species, the coastal whiptail, which would be mitigated to a less than significant level through implementation of MM BIO-1.The Project would also potentially result in significant impacts related to migratory birds, whichwould be mitigated through implementation of MM BIO-2. Regarding cultural resources, the Project could potentially encounter unknown archaeological resources that would result in a significant impact prior to mitigation; however, with implementation of MM CUL-1 the Project'simpact would be reduced to a less than significant level. Regarding geology and soils, the Projecthas the potential to encounter unknown paleontological resources that would result in a significantimpact prior to mitigation; however, with implementation of MM GEO-1, the Project's impactrelated to paleontological resources would be reduced to a less than significant level. Regarding tribal cultural resources, the Project has potential to encounter unknown tribal cultural resourcesthat would result in a significant impact prior to mitigation; however, with implementation of MM TCR-1 through MM TCR-3, the Project's impact related to tribal cultural resources would bereduced to a less than significant level. 4-86 Environmental Assessment
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b) Does the project have impacts that are individually limited, but cumulatively considerable? ("Cumulatively considerable" means that the incremental effects ofa project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable futureprojects)? Less Than Significant Impact. The Project would not have adverse environmental impacts at asignificant level for any resource topics. All potential significant impacts would be reduced to less than significant levels with implementation of MMs. No significant cumulative effects are anticipated because no resources would be adversely affected by the Project, or the Project effects would be localized and of limited extent. A less than significant impact would occur in relation to cumulatively considerable effects.c) Does the project have environmental effects which will cause substantial adverse effects on human beings, either directly or indirectly? Less Than Significant With Mitigation. The Project would result in less than significant impacts related to air quality and public services, and the Project would result in less than significantimpacts with mitigation related to geology and soils, hazards and hazardous materials, and noise.

Therefore, the Project would not cause significant adverse effects to human beings, either directly or indirectly. With implementation of mitigation, the Project would result in less than significant impacts related to this threshold.
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SECTION 5.0 DOCUMENT PREPARERS AND CONTRIBUTORS
Pasadena Water and Power
Principal Engineer....................................................................................... Michele CarinaEngineer................................................................................................... Johnathan Giang Psomas
Senior Project Manager ..........................................................................Alia hlokuki, AICPProject Manager............................................................................................ Scan NoonanEnvironmental Planners................................. Jessica Hitchcock and Jordan Werkmeister Air Quality, Greenhouse Gas, and Noise Specialist..........................................Tin Cheung Cultural Resources Manager.................................................................. Charles Cisneros Biological Resources Manager...................................................................... Marc T. Blain GIS/Graphics.................................................................. Jim McPherson and Paul O'BrienTechnical Editor.........................................................................................Danae OvermanWord Processor.............................................................................................. Sheryl Kristal 5-1 Document Preparers and Contributors
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5-2 Document Preparers and Contributors
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SECTION 6.0 REFERENCES
California Air Resources Board (CARB). 2016. California AmbientAir Quality Standards (CAAQS).

Sacramento, CA: CARB. https://ww2.arb.ca.gov/sites/defaulVfiles/2020-07/aaqs2.pdf -. 2011. AB 32 Global Warming Solutions Act of 2006. Sacramento, CA: CARB. https://ww2.arb.ca.gov/resources/fact-sheets/ab-32-global-warming-solutions-act-2006 California Buildings Standards Commission (CBSC). 2022. 2022 California Building Standards Code (Cal. Code Regs., Title 24). Sacramento, CA: CBSC. https://www.dgs.ca.gov/BSC/Codes.

California Department of Conservation. 2023a. California Important Farmland Finder.

Sacramento, CA: DOC. https://maps.conservation.ca.gov/DLRP/CIFF/. -.2023b. California Earthquake Hazards Zone Application (EQ Zapp). Sacramento, CA:

DOC. https://www.conservation.ca.gov/cgs/geohazards/eq-zapp -.2023c. Landslide Inventory (beta) web mapper. Sacramento, CA: DOC. https://maps.conservation.ca.gov/cgs/lsi/
California Department of Forestry and Fire Protection (CAL FIRE). 2023. FHSZ Viewer.

Sacramento, CA: CAL FIRE. https://egis.fire.ca.gov/FHSZ/.

California Department of Transportation (Caltrans). 2023. California State Scenic Highway System. Sacramento, CA: Caltrans.https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=465dfd3d807c46cc8 e8057116f1aacaa.
-. 2013. Technical Noise Supplement to the Traffic Noise Analysis Protocol. Sacramento, CA: Caltrans. https://dot.ca.gov/-/media/dot-media/programs/environmentalanalysis/documents/env/tens-sep2013-a11y.pdf California Department of Water Resources (DWR). 2023. Basin Prioritization. Sacramento, CA:

DWR. https://water.ca.gov/Programs/Groundwater-Management/Basin-Prioritization.

California Geological Survey (CGS). 2010. Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate in the San Gabriel Valley Production-Consumption Region, Los Angeles County, California. Sacramento, CA: CGS. -. 1982. Special Report 143, Part IV: Mineral Land Classification of the Greater Los Angeles Area. Sacramento, CA: CGS. http://ibecproject.com/PREDEIR_0000004.pdf California Air Pollution Control Officers Association (CAPCOA). 2022. California Emissions Estimator Model (CalEEMod). Sacramento, CA: CAPCOA. https://www.caleemod.com/.

U.S. Census Bureau. 2022. Population Estimates for the City of Pasadena. https://data.census.gov/.

Converse Consultants (Converse). 2016. Phase II Environmental Site Assessment Report, Arroyo Seco Project, Pasadena, CA. Prepared for Carollo Engineers. Los Angeles, CA. 6-1 References
Explorer Well Project
Initial Study/Mitigated Negative Declaration
. 2013. Geotechnical Feasibility Study Report Proposed Public Restroom, Roadway Improvement and Stormwater Sediment Basins Project, Arroyo Seco Canyon, Pasadena Federal Emergency Management Agency (FEMA). 2008. Flood Insurance Rate Map- Map No. 06037C1375F. Washington, D.C.: FEMA.

Federal Highway Administration (FhlWA). 2011. Highway Traffic Noise: Analysis and Abatement Guidance (FHWA-HEP-10-025). Washington, D.C.: FHWA.
https://www.fhwa.dot.gov/environment/noise/regulations_and_guidance/analysis_and_abatement_guidance/revguidance.pdf Federal Transit Administration (FTA). 2018. Transit Noise and Vibration Impact Assessment Manual. Washington, D.C.: FTA.
https://www.transit.dot.gov/sites/fta.dot.gov/files/docs/researchinnovation/118131/transit-noise-and-vibration-impact-assessment-manual-fta-report-no0123_0.pdf Intergovernmental Panel on Climate Change (IPCC). 2013. Climate Change 2013: The Physical Science Basis.https://www.ipcc.ch/site/assets/uploads/2018/03/WG1AR5_SummaryVolume_FINAL.pdf Leighton Consulting, Inc. 2018. Geotechnical Exploration, Jet Propulsion Laboratory, Monk Hill Treatment System Optimization, Explorer Well & Behner Water Treatment Plan, Hahamonga Watershed Park, JPL East Parking Lot, 3200 Explorer Road (Geotechnical Report). Pasadena, California, Civiltec Project No. 2017170.00.

Los Angeles County. 2023. Disaster Routes - Pasadena. Los Angeles, CA: Los Angeles County. https://dpw.lacounty.gov/dsg/DisasterRoutes/map/Pasadena.pdf Los Angeles County Public Works (LACPW). 2023. County of Los Angeles Countywide Integrated Waste Management Plan, 2022 Annual Report. Los Angeles, CA: LACPW. https://pw.lacounty.gov/epd/swims/News/swims-more-links.aspx?id=4#.

National Aeronautics and Space Administration (NASA). 2014. Final Optimization Work Plan.

Pasadena, CA: NASA.

Pasadena, City of. 2023a. Pasadena On-Line Zoning Code, Title 17. City of Pasadena, CA: City of Pasadena. https://library.municode.com/ca/pasadena/codes/code_of_ordinances -.2023b. Fire Zone Map. City of Pasadena, CA: City of Pasadena. https://www.cityofpasadena.net/fire/wp-content/uploads/sites/25/Fire-Zone-Map.pdf -. 2022. Transportation Impact Analysis Guidelines. Pasadena, CA: City of Pasadena. https://www.cityofpasadena.net/transportation/wp-content/uploads/sites/20/City-ofPasadena-TIA-Guidelines.pdf -. 2020a. Draft Environmental Impact Report for the Arroyo Seco Canyon Project.

Pasadena, CA: City of Pasadena. https://pwp.cityofpasadena.net/arroyosecoproject/ -. 2020b. Cultural Resources Technical Report for the Arroyo Seco Canyon Project.

Pasadena, CA: City of Pasadena. https://pwp.cityofpasadena.net/wpcontent/uploads/2020/06/App-E-1_Cultural-Resources-Tech-Report.pdf 6-2 References
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2019. City of Pasadena Zoning Map. Pasadena, CA:
https://ww5.cityofpasadena.net/planning/wpcontenVuploads/sites/56/2017/09/Zoning_Map_2019-09-28.pdf City of Pasadena.
-. 2018. Pasadena Climate Action Plan (CAP). Pasadena, CA: City of Pasadena. https://www.cityofpasadena.net/planning/wp-content?uploads/sites/30/Final-PasadenaClimate-Action-Plan_3.5.2018.pdf?v=1702590115051 2016. 2016 Public Health Goals Report. Pasadena, CA: City of Pasadena.https://pwp.cityofpasadena.net/wpcontent/uploads/2017/08/PWP_PublicHealthGoalReport.pdf -. 2015a. Draft Environmental Impact Report for the Pasadena General Plan, Volume IIAppendices. Pre Pasadena, CA: City of Pasadena. https://ww5.cityofpasadena.nefplanning/wp-content/uploads/sites/56/2015/09/GeneralPlan_Draft-EIR_Appendices_2015-01. pdfD?v= 1692215584642 -. 2012. Pasadena Open Space and Conservation Element. Pasadena, CA: City of Pasadena. https://www.cityofpasadena.net/planning/wpcontent/uploads/sites/30/General-Plan-Open-Space-and-Conservation-Element2012.pdf -. 2011 a. Pasadena Emergency Operations Plan. Pasadena, CA: City of Pasadena. http://ww2.cityofpasadena.net/councilagendas/2012%20agendas/Jan_30_12/AR%2010%20Emergency%200perations%20Plan%202011.pdf. -. 2011b. Monk Hill Treatment System Project Evaluation Summary. Pasadena, CA: City of Pasadena.https://altadenablog.altadenahistoricalsociety.org/archive/ww2.cityofpasadena.net/water andpower/monkhill/CDPHMonkHillProjectEvalSummary021111 l.pdf Pasadena Water and Power. 2021. 2020 Urban Water Management Plan. Pasadena, CA: PWP. https://pwp.cityofpasadena.neVwp-content/uploads/2021/06/Final-2020-Urban-WaterManagement-Plan-Reduced.pdf South Coast Air Quality Management District (SCAQMD). 2023. Air Quality Significance Thresholds. Diamond Bar, CA: SCAQMD. /https://www.aqmd.gov/docs/defaultsource/ceqa/handbook/south-coast-aqmd-air-quality-significancethresholds. pdf?sfvrsn=25 2022. 2022 Air Quality Management Plan. Diamond Bar, CA: SCAQMD. http://www.aqmd.gov/home/air-quality/clean-air-plans/air-quality-mgt-plan -. 2017. National Ambient Air Quality Standards (NAAQS) and California Ambient Air Quality Standards (CAAQS) Attainment Status for South Coast Air Basin. Diamond Bar, CA:

SCAQMD. http://www.aqmd.gov/docs/default-source/clean-air-plans/air-qualitymanagement-plans/naaqs-caaqs-feb2016.pdf?sfvrsn=2. -. 2009. Localized Significance Thresholds: Thresholds for Construction and Operation with Gradual Conversion of NOx to N02. Diamond Bar, CA: SCAQMD. http://www.aqmd.gov/docs/default-source/ceqa/handbook/localized-significancethresholds/appendix-c-mass-rate-lst-look-up-tables.pdf?sfvrsn=2 6-3 References
Explorer Well Project
Initial Study/Mitigated Negative Declaration
. 2003. Potential Control Strategies to Address Cumulative Impacts from Air Pollution White Paper. Diamond Bar, CA: SCAQMD. ://www.aqmd.gov/docs/defaultsource/Agendas/Environmental-Justice/cumulative-impacts-working-group/cumulativeimpacts-white-paper.pdf 1993. CEQAAir Quality Handbook (1993). SCAQMD. Diamond Bar, CA.

State Water Resources Control Board. 2020. Process Memo 97-005-R2020. https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/docs/process_mem o_97-005-r2020_v7.pdf
U.S. Environmental Protection Agency (EPA). 2022. Nonattainment Areas for Criteria Pollutants (Green Book). Washington, D.C.: EPA. https://www.epa.gov/green-book -. 1971 a. Noise from Construction Equipment and Operations, Building Equipment, and Home Appliances. Washington, D.C.: EPA.
https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=9101NN3I.TXT 1971 b. Effects of Noise on People. Washington, D.C.: EPA. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=91019R7C.TXT Walker, Edwin F. 1951. Five Prehistoric Archaeological Sites in Los Angeles County, California.

Southwest Museum, F.W. Hodge Anniversary Fund VI, Los Angeles.

World Health Organization (WHO). 1995. Community
https://www.nonoise.org/library/whonoise/whonoise.htm
Noise.
6-4 References
Appendix A
Air Quality Calculations

APPENDIX A

AIR QUALITY CALCULATIONS
Explorer Well v4 Detailed Report, 11/7/2023
Explorer Well v4 Detailed Report
Table of Contents

1. Basic Project Information

1.1. Basic Project Information1.2. Land Use Types1.3. User-Selected Emission Reduction Measures by Emissions Sector

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds2.2. Construction Emissions by Year, Unmitigated

3. Construction Emissions Details

3.1. Site Preparation/Mobilization (2024) - Unmitigated3.3. Noise Barriers (2024) - Unmitigated3.5. Well Drilling (2024) - Unmitigated3.7. Well Drilling Continued (2024) - Unmitigated3.9. Well Development (2024) - Unmitigated

3.11. Install Test Pump, Well Testing and Sampling (2024) - Unmitigated 1/50
Explorer Well v4 Detailed Report, 11/7/2023

3.13. Equipment Installation (2024) - Unmitigated

3.15. Equipment Installation (2025) - Unmitigated

3.17. Site Development (2024) - Unmitigated3.19. Site Development (2025) - Unmitigated

3.21. Building Construction (2024) - Unmitigated

3.23. Building Construction (2025) - Unmitigated

3.25. Paving (2024) - Unmitigated3.27. Paving (2025) - Unmitigated

3.29. Architectural Coatings (2024) - Unmitigated

3.31. Architectural Coatings (2025) - Unmitigated

3.33. Linear, Grading & Excavation (2024) - Unmitigated

3.35. Linear, Drainage, Utilities, & Sub-Grade (2024) - Unmitigated3.37. Linear, Paving (2024) - Unmitigated

4. Operations Emissions Details

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated 2/50
Explorer Well v4 Detailed Report, 11/7/2023

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated

5. Activity Data

5.1. Construction Schedule

5.2. Off-Road Equipment

5.2.1. Unmitigated

5.3. Construction Vehicles

5.3.1. Unmitigated

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies

5.5. Architectural Coatings

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities5.6.2. Construction Earthmoving Control Strategies

5.7. Construction Paving5.8. Construction Electricity Consumption and Emissions Factors5.18. Vegetation

5.18.1. Land Use Change
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5.18.1.1. Unmitigated

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated

5.18.2. Sequestration

5.18.2.1.unmiti9ated

6. Climate Risk Detailed Report

6.1. Climate Risk Summary

6.2. Initial Climate Risk Scores6.3. Adjusted Climate Risk Scores6.4. Climate Risk Reduction Measures

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores7.2. Healthy Places Index Scores7.3. Overall Health & Equity Scores

7.4. Health & Equity Measures7.5. Evaluation Scorecard

7.6. Health & Equity Custom Measures
4/50
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8. User Changes to Default Data
5/50
Explorer Well v4 Detailed Report, 11/7/2023

1. Basic Project Information

1.1. Basic Project Information
Data FieldProject NameConstruction Start DateLead AgencyLand Use Scale Analysis Level for DefaultsWindspeed (m/s)
Precipitation (days)
LocationCounty
City
Air DistrictAir BasinTAZ
EDFZElectric Utility
Gas Utility
App Version

1.2. Land Use Types
Land Use Subtype | Size
Other AsphaltSurfaces

9.75 Unit1000sqft
fc' ] Lot Acreage

0.22 lvalue
Explorer Well v4
4/1/2024
Project/site
County

2.505.20
Explorer Rd, Pasadena, CA, USALos Angeles-South CoastPasadena South Coast AQMD
South Coast
49307
Pasadena Water & PowerSouthern California Gas
2022.1.1.20
Building Area (sq ft) | Landscape Area (sq | Special Landscape | Population I ft) I Area (sq ft)

0.00 6/50
Description
Explorer Well v4 Detailed Report, 11/7/2023
User DefinedIndustrial
600
User Defined Linear 0.15
User Defined Unit 0.15
Mile 0.02
600

0.00 0.00

1.3. User-Selected Emission Reduction Measures by Emissions Sector No measures selected

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Un/Mlt. IROG.

Daily. Summer —
(Max)
Unmit. 3.43
Daily, Winter —
(Max)
Unmit. 1.72
Average Daily —
(Max)
Unmit. 1.05
Annual (Max) —
Unmit. 0.19
INOx31.5

15.2 g.33
I co47.5

23.4 15.2
|S020.070.03

0.02 IPM10E1.34

0.660.36
IPM10D

0.700.280.180.03
IPM10T2.030.940.54

1.70 2.78 < 0.005 0.07 0.10

2.2. Construction Emissions by Year, UnmitigatedCriteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Year
Daily - Summer —
(Max)
PM10E PM10D
IPM2.5E

1.23 0.610.330.06
IPM2.5D0.170.01
[PM2.5T

0.07 0.670.04 0.37

0.07 |C02e

1.39 7,748
3,642
2,387
395
7/50
Explorer Well v4 Detailed Report, 11/7/2023
2024
2025
Daily - Winter
(Max)
20242025Average Daily20242025
Annual
2024
2025

3.43 1.601.721.60

0.85 1.05

0.15 0.19

31.5 14.215.214.2

7.579.33

1.381.70

47.5 23.423.423.2

11.3 15.2

2.072.78

0.07 0.030.030.030.020.02< 0.005< 0.005

1.34 0.550.660.550.320.36

0.060.07

0.70 0.280.280.280.180.180.030.03

2.03 0.830.940.830.50

0.54 0.09

0.10 1.23

0.510.610.510.290.330.050.06

0.17 0.070.070.070.040.040.010.01

1.39 0.570.670.570.340.370.060.07
7,748
3,6523,6423,636
1,843
2,387305395

3. Construction Emissions Details3.1. Site Preparation/Mobilization (2024) - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
ROG
Daily, Summer —
(Max)
Off-RoadEquipment

0.63 Dust From —Material
Movement
Onsite truck 0.00
Daily, Winter —(Max)
NOx

6.630.00
co

7.47 0.00
S02

0.020.00
PM10E

0.270.00
PM 100 PM10T PM2.5E PM2.5D PM2.5T C02e

0.27 < 0.005 < 0.005

0.25 — 0.25 1,668
< 0.005 < 0.005 —

0.00 0.00 0.00 0.00 0.00 0.00
8/50
Explorer Well v4 Detailed Report, 11/7/2023
Average Daily —
Off-Road
Equipment
Dust From
Material
Movement
Onsite truckAnnualOff-Road
Equipment
Dust FromMaterialMovement
Onsite truck
Offsite
Daily, Summer
(Max)Worker
VendorHauling
Daily, Winter(Max)
Average Daily
Worker
Vendor
Hauling
Annual
Worker
VendorHauling

0.03 0.000.01

0.000.030.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005

0.29 0.000.05

0.000.040.000.18< 0.0050.000.01
< 0.005

0.00< 0.005

0.33 0.000.060.000.570.000.07

0.020.00< 0.005< 0.0050.00< 0.005
< 0.005

0.00< 0.0050.000.000.00< 0.0050.000.00
< 0.005

0.000.00
< 0.005

0.01 0.00< 0.0050.000.000.00< 0.0050.000.00
< 0.005

0.000.00
< 0.005
< 0.0050.00< 0.0050.000.100.000.04
< 0.005

0.00 < 0.005
< 0.0050.00
< 0.005

0.01 < 0.005

0.00 < 0.005< 0.0050.000.100.000.04< 0.0050.00< 0.005< 0.0050.00< 0.005

0.01 — 0.01 73.1
< 0.005 < 0.005 —

0.00 0.00

0.000.000.00< 0.0050.000.00< 0.0050.000.00< 0.005

0.000.020.00

0.01< 0.0050.00< 0.005< 0.0050.00< 0.005

0.00 0.00
< 0.005 — < 0.005 12.1
< 0.005 < 0.005 —

0.000.020.000.01< 0.0050.00< 0.005< 0.0050.00< 0.005

0.00 107

0.00 148

4.530.006.490.750.00

1.07 9/50
Explorer Well v4 Detailed Report, 11/7/2023

3.3. Noise Barriers (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
ROG
Daily, Summer —
(Max)
Off-RoadEquipment

0.36 Onsite truck 0.00
Daily, Winter —
(Max)
Average Daily —
Off-Road 0.06
Equipment
Onsite truckAnnualOff-RoadEquipmentOnsite truck
Offsite

0.000.010.00
Daily, Summer —
(Max)
Worker
Vendor
Hauling

0.03 0.000.00
Daily, Winter —(Max)Average Daily —Worker 0.01
NOx

3.830.00

0.690.000.130.000.04

0.000.000.01
co6.230.00

1.13 0.000.210.00

0.570.000.000.09
S02

0.010.00
< 0.0050.00< 0.0050.00

0.000.000.000.00
PM10E

0.160.00

0.03 0.000.010.000.000.00

0.00 0.00
PM 100

0.00 0.000.00

0.100.000.000.02
10/50
PM10T

0.160.00

0.030.000.010.000.100.00

0.00 0.02
PM2.5E

0.150.00

0.030.00< 0.0050.00

0.000.000.000.00
IPM2.5D0.00

0.000.000.020.00

0.00 < 0.005
IPM2.5T0.150.00

0.030.00
< 0.0050.000.020.000.00< 0.005
|C02e
9660.00
175

0.0028.90.00
107

0.000.00

18.7 Explorer Well v4 Detailed Report, 11/7/2023
Vendor
Hauling
Annual
Worker
Vendor
Hauling

0.000.00
< 0.0050.000.00

0.000.00

0.020.000.00

0.000.00

0.000.000.00

0.000.00

0.000.000.00

0.000.00
< 0.0050.000.00

0.000.00

0.000.000.00

0.000.00
< 0.005

0.000.00

0.000.00
< 0.005

0.000.00

3.09 0.000.00

3.5. Well Drilling (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) Location
Onsite
IROG
Daily, Summer —
(Max)Off-Road
Equipment

1.24 Dust From —MaterialMovementOnsite truck 0.00
Daily, Winter —(Max)
Average Daily —
Off-Road 0.10
EquipmentDust From —MaterialMovement
Onsite truck
Annual

0.00 |NOx

11.0 0.000.870.00
I co

15.3 0.00

1.21 0.00
|S02 PM10E0.02 0.40

0.00 0.000.00 0.00
PM10D

0.000.00
IPM10T PM2.5E PM2.5D IPM2.5T C02e

0.40 < 0.005 < 0.005

0.36 — 0.36 2,290
< 0.005 < 0.005 —

0.00 0.00
< 0.005 0.03 - 0.03
< 0.005 < 0.005

0.00 0.00

0.00 0.00 0.00

0.03 — 0.03 182
< 0.005 < 0.005 —

0.00 0.00 0.00
11/50
Off-Road
Equipment
Dust FromMaterialMovementOnsite truck
Offsite
Daily, Summer
Worker
VendorHauling
Daily, Winter(Max)Average Daily
Worker
Vendor
HaulingAnnual
Worker
VendorHauling

0.02 0.000.040.00< 0.005< 0.005

0.00 < 0.005
< 0.0050.00< 0.005

0.16 0.000.050.000.06< 0.005

0.00 < 0.005
< 0.0050.00< 0.005

0.22 0.000.750.000.020.050.00
< 0.0050.010.00< 0.005
< 0.005

0.000.000.00< 0.0050.000.00< 0.0050.000.00< 0.005

0.01 0.000.000.00< 0.0050.000.00< 0.005

0.000.00< 0.005
< 0.0050.00

0.130.000.010.010.00< 0.005< 0.0050.00< 0.005

0.01 < 0.0050.000.130.000.01

0.010.00
< 0.005< 0.005

0.00< 0.005

3.7. Well Drilling Continued (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) Explorer Well v4 Detailed Report, 11/7/2023

0.01 — 0.01 30.1
< 0.005 < 0.005 —

0.000.000.00< 0.0050.000.00< 0.0050.000.00< 0.005

0.000.030.00< 0.005< 0.0050.00< 0.005< 0.005

0.00< 0.005
Location
Onsite
IROG NOx I co |S02 PM10E PM10D PM10T

0.000.030.00< 0.005< 0.0050,00< 0.005< 0.0050.00< 0.005

0.00 143

0.00 48.6

10.90.003.851.81

0.000.64
PM2.5T C02e
Daily, Summer —
(Max)
12/50
Explorer Well v4 Detailed Report, 11/7/2023
Off-RoadEquipment

1.62 Dust From —MaterialMovement
Onsite truck
Onsite truck
Offsite

0.00 Daily, Winter —(Max)
Average Daily —
Off-Road 0.08
EquipmentDust From —
MaterialMovement

0.000.01
Onsite truckAnnual
Off-Road
Equipment
Dust From —
Material
Movement

0.00 Daily, Summer —
(Max)Worker
Vendor
Hauling

0.060.00< 0.005
Daily, Winter —
(Max)
Average Daily —
Worker < 0.005

15.8 0.000.780.000.140.000.060.000.19
< 0.005

21.60.00 1.06

0.000.190.00

0.94 0.00

0.070.04

0.030.00

0.660.00

0.66 < 0.005 < 0.0050.00 0.00
< 0.005 0.03 0.03
< 0.005 < 0.005

0.00< 0.0050.000.000.00< 0.0050.00

0.000.010.00

0.00 0.00

0.600.000.030.00

0.60 3,456
< 0.005 < 0.005 —0.00 0.00 0.00

0.03 170
< 0.005 < 0.005 —0.00 0.00 0.00

0.01 0.01
< 0.005 < 0.005 —

0.01 28.2
< 0.005 < 0.005 —

0.00 0.00 0.160.00 0.00< 0.005 0.040.00 0.01
13/50

0.000.160.000.040.01

0.000.000.00< 0.0050.00

0.000.040.000.01< 0.005

0.000.040.000.01
< 0.005

0.00 179

0.00 156

8.49 Explorer Well v4 Detailed Report, 11/7/2023
Vendor
Hauling
Annual
Worker
VendorHauling

0.00< 0.005< 0.0050.00< 0.005

0.000.01< 0.0050.00
< 0.005

0.00< 0.0050.010.00< 0.005

0.00< 0.0050.000.00< 0.005

0.00< 0.005< 0.0050.00< 0.005

0.00 < 0.005
< 0.005

0.00< 0.005

3.9. Well Development (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual)

0.00< 0.0050.000.00< 0.005

0.00< 0.005< 0.0050.00< 0.005

0.00 7.71

1.41 0.00

1.28 Location ROG NOx I CO |S02 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T C02e Daily, Summer —
(Max)
Onsite truck 0.00Daily, Winter —
(Max)
Average Daily —
Off-Road 0.05
Equipment
Onsite truck 0.00Off-Road 0.01
Equipment
Onsite truck 0.00
Explorer Well v4 Detailed Report, 11/7/2023
Worker
Vendor
Hauling
Daily, Winter
(Max)
Average DailyWorkerVendor
HaulingAnnual
Worker
VendorHauling
< 0.005< 0.005

0.00< 0.005
< 0.005

0.00 < 0.005< 0.0050.00
< 0.005< 0.005

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.02< 0.005

0.00< 0.005< 0.0050.00
< 0.005
< 0.0050.00

0.00< 0.005

0.000.00< 0.0050.000.00< 0.0050.00

0.00< 0.005

0.000.00< 0.0050.000.00< 0.0050.00
< 0.005< 0.005

0.00< 0.005< 0.0050.00
< 0.005
< 0.0050.00
< 0.005< 0.005

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.11. Install Test Pump, Well Testing and Sampling (2024) - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) Location
Onsite
IROG
Daily, Summer —
(Max)
Off-Road 0.08
Equipment
Onsite truck 0.00
Daily, Winter —(Max)
Average Daily —Off-Road < 0.005
Equipment
Onsite truck 0.00
|NOx0.630.000.040.00
co

0.430.000.02

0.00 |S02< 0.0050.00< 0.0050.00
PM10E

0.030.00< 0.0050.00
PM10D

0.000.00
15/50
PM10T

0.030.00< 0.0050.00

0.00< 0.005

0.000.00< 0.0050.000.00
< 0.005

0.00 < 0.005< 0.005

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00
PM2.5E

0.020.00< 0.0050.00
PM2.5D

0.00 < 0.005 3.61
< 0.005 3.31

0.00 0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.120.120.000.020.020.00

0.00 PM2.5T

0.020.00
< 0.005

0.00 C02e

81.90.004.710.00
Explorer Well v4 Detailed Report, 11/7/2023
Annual
Off-RoadEquipmentOnsite truck
Offsite
Daily, Summer
(Max)
Worker
VendorHauling
Daily, Winter
(Max)
Average Daily
Worker
VendorHauling
Annual
Worker
Vendor
Hauling
< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.010.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00 < 0.0050.000.02< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.005

0.00 0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00 < 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.13. Equipment Installation (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
IROG |NOx I co |S02 PM10E PM10D PM10T
Daily, Summer —
(Max)Daily, Winter —(Max)
< 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00 PM2.5E PM2.5D
< 0.005 0.780.00 0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.613.31

0.000.200.190.000.030.030.00
PM2.5T C02e
16/50
Explorer Well v4 Detailed Report, 11/7/2023
Off-Road
Equipment
Onsite truck
Average Daily
Off-Road
Equipment
Onsite truck
Annual
Off-Road
EquipmentOnsite truck
Offsite
Daily, Summer
(Max)
Daily, Winter
(Max)Worker
VendorHauling
Average Daily
Worker
Vendor
HaulingAnnual
Worker
Vendor
Hauling

0.36 0.000.020.00< 0.0050.00< 0.005< 0.0050.00< 0.005
< 0.005

0.00 < 0.005
< 0.0050.00

3.83 0.000.230.000.040.00

6.23 0.000.380.000.070.00

0.01 0.00< 0.0050.00< 0.0050.00

0.16 0.000.010.00< 0.0050.00

0.000.000.00
< 0.005
< 0.005

0.00< 0.005
< 0.005

0.00 < 0.005< 0.005

0.00 0.02< 0.0050.00< 0.005
< 0.005

0.00 < 0.005< 0.005

0.00 0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00 < 0.005

0.00 0.00< 0.0050.000.00< 0.0050.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.16 0.000.010.00< 0.0050.00

0.15 0.00

0.01 0.00
< 0.0050.00

0.000.000.00
< 0.005< 0.0050.00
< 0.005
< 0.0050.00< 0.005< 0.0050.00

0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.15 0.000.010.00< 0.0050.00
966

0.00 58.60.00
g.70

0.00 < 0.005
< 0.005

0.00< 0.005
< 0.005

0.00 < 0.005
< 0.0050.00

3.413.310.000.210.200.000.030.030.00

3.15. Equipment Installation (2025) - Unmitigated
17/50
Explorer Well v4 Detailed Report, 11/7/2023
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location ROG
Onsite
Daily, Summer
Off-Road
EquipmentOnsite truck
Daily, Winter
(Max)
Off-RoadEquipmentOnsite truck
Average DailyOff-Road
Equipment
Onsite truck
AnnualOff-Road
Equipment
Onsite truck
Offsite
Daily, Summer
(Max)
Worker
Vendor
Hauling
Daily, Winter
Worker
Vendor

0.320.000.320.000.210.000.040.00< 0.005< 0.005

0.00< 0.005< 0.005
NOx

3.480.003.480.002.280.000.420.00
< 0.005< 0.0050.00< 0.005< 0.005
I co

6.200.006.200.004.060.000.740.00

0.02< 0.0050.000.01< 0.005
|S020.010.000.010.000.010.00< 0.005

0.000.00< 0.0050.000.00< 0.005
PM10E

0.120.00

0.120.000.080.000.010.00
PM10D

0.000.000.00

0.00 0.00 < 0.005< 0.005 < 0.005

0.00 0.000.00< 0.005
< 0.005< 0.005
18/50
PM10T

0.120.000.120.000.080.000.010.00< 0.005< 0.005

0.00< 0.005< 0.005
PM2.5E

0.110.000.110.000.070.00

0.010.000.00< 0.0050.000.00< 0.005
IPM2.5D

0.000.000.000.00< 0.005< 0.0050.00< 0.005
< 0.005
PM2.5T

0.110.000.110.00

0.07 0.00

0.010.00< 0.005< 0.0050.00< 0.005< 0.005
|C02e
9670.009670.006340.00
105

0.003.543.260.003.343.26
Explorer Well v4 Detailed Report, 11/7/2023
Hauling 0.00Average Daily —
Worker
VendorHauling
Annual
WorkerVendor
Hauling
< 0.005< 0.0050.00< 0.005< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.000.01< 0.0050.00< 0.005< 0.0050.00

0.000.00< 0.0050.00

0.00 < 0.0050.00

0.000.00< 0.0050.000.00< 0.0050.00

0.00 < 0.005
< 0.0050.00< 0.005< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.17. Site Development (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
IROG |NOx I CO |S02 IPM10E PM10D [PM10T
Daily, Summer —
(Max)Daily, Winter —(Max)
Off-Road 0.24EquipmentOnsite truck 0.00Average Daily —Off-Road 0.01EquipmentOnsite truck Annual
Off-RoadEquipmentOnsite truck

0.00< 0.0050.00

2.400.000.150.000.030.00

3.830.000.230.00

0.040.00

0.010.00< 0.0050.00< 0.0050.00

0.110.000.010.00< 0.0050.00

0.000.00

0.00 19/50

0.110.000.010.00< 0.0050.00

0.000.00
< 0.0050.00

0.00< 0.0050.00

0.00< 0.005< 0.0050.00
< 0.005< 0.0050.00

0.002.23

2.14 0.000.370.350.00
IPM2.5E PM2.5D PM2.5T |C02e0.100.000.010.00
< 0.0050.00

0.000.00

0.00 0.100.000.010.00
< 0.0050.00
583

0.00 35.40.00

5.860.00
Explorer Well v4 Detailed Report, 11/7/2023
Offsite
Daily, Summer
(Max)Daily, Winter(Max)
WorkerVendorHaulingAverage Daily
Worker
VendorHauling
Annual
WorkerVendor
Hauling
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005
< 0.0050.00

0.02 < 0.005

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

0.00 < 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.19. Site Development (2025) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual)

0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

0.00 < 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

3.413.310.000.210.200.000.030.030.00
IPM10D IPM10T
Onsite truck 0.00
Daily. Winter —(Max)
Explorer Well v4 Detailed Report, 11/7/2023
Off-Road
EquipmentOnsite truckAverage Daily
Off-Road
EquipmentOnsite truck
AnnualOff-Road
EquipmentOnsite truck
Offsite
Daily, Summer
WorkerVendor
HaulingDaily, Winter
(Max)Worker
VendorHaulingAverage Daily
Worker
VendorHauling
Annual
Worker
Vendor

0.21 0.000.140.00

0.030.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

2.20 0.00

1.44 0.00

0.260.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005
< 0.005

0.00< 0.005< 0.005

3.820.002.500.00

0.46 0.00

0.02< 0.0050.000.01< 0.0050.000.01< 0.0050.00< 0.005< 0.005

0.010.00
< 0.0050.00
< 0.0050.00

0.00< 0.0050.000.00
< 0.0050.000.00< 0.0050.00

0.00< 0.005

0.080.000.060.000.010.00

0.00< 0.0050.000.00
< 0.005

0.000.00< 0.0050.000.00< 0.005

0.000.000.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00
< 0.005
< 0.005

0.080.000.060.000.010.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

0.080.000.050.00

0.01 0.00

0.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00< 0.005

0.00 0.00

0.00 < 0.005
< 0.005

0.00< 0.005
< 0.005

0.00 < 0.005
< 0.0050.00< 0.005< 0.005

0.080.000.050.00

0.01 0.00
< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00
< 0.005
< 0.005
5830.003820.0063.30.00

3.543.260.003.343.260.00

2.23 2.140.000.370.35
21/50
Explorer Well v4 Detailed Report, 11/7/2023
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00

3.21. Building Construction (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) |S02 PM10E PM 100 PM10T

0.00 0.00 0.00 0.00
PM2.5D
Explorer Well v4 Detailed Report, 11/7/2023
WorkerVendor
HaulingAnnualWorkerVendorHauling
< 0.005< 0.005

0.00< 0.005< 0.0050.00
< 0.005< 0.005

0.00< 0.005
< 0.0050.00

0.00< 0.005

0.00 0.00< 0.0050.00

0.00< 0.005

0.000.00
< 0.005

0.00 < 0.005
< 0.005

0.00 < 0.005< 0.0050.00
< 0.005< 0.005

0.00< 0.005< 0.0050.00

0.00< 0.005

0.000.00< 0.0050.00
< 0.005< 0.005

0.00< 0.005< 0.0050.00
< 0.005
< 0.005

0.00 < 0.005
< 0.0050.00

0.210.20

0.000.030.030.00

3.23. Building Construction (2025) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
IROG
Daily, Summer —
(Max)
Off-Road
Equipment
Onsite truck

0.210.00
Daily, Winter —
(Max)
Off-Road
EquipmentOnsite truck

0.210.00
Average Daily —Off-Road
Equipment
Onsite truckAnnual
Off-Road
Equipment

0.14 0.000.03
NOx

2.200.00

1.44 0.000.26
I co

3.820.003.820.002.500.000.46
|S02

0.010.000.010.00< 0.005

0.00 < 0.005
IPM10E

0.080.00

0.080.000.06

0.000.01
PM10D

0.000.00

0.00 PM10T

0.080.000.080.000.060.000.01
PM2.5E

0.080.000.080.000.05

0.00 0.01
PM2.5D

0.000.000.00
PM2.5T

0.080.000.08

0.000.05

0.000.01
C02e
5830.00
5830.00382

0.0063.3
23/50
Explorer Well v4 Detailed Report, 11/7/2023
Onsite truck
Offsite
Daily, Summer
(Max)
Worker
Vendor
Hauling
Daily, Winter
(Max)
Worker
Vendor
Hauling
Average Daily
WorkerVendorHauling
Annual
Worker
Vendor
Hauling

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00 < 0.005< 0.0050.00

0.00 0.02
< 0.0050.00

0.01 < 0.005

0.000.01< 0.0050.00< 0.005< 0.0050.00

0.000.00< 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.0050,00

0.000.00< 0.0050.000.00< 0.0050.00

0.00 < 0.005

0.000.00< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

0.00< 0.005< 0.0050.00

0.00 < 0.005
< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005

0.00 3.25. Paving (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) IPM10E PM10D
Onsite —
Daily, Summer —
(Max)
Daily, Winter —
(Max)

0.00 0.00
< 0.005

0.000.00< 0.0050.000.00
< 0.005

0.000.00< 0.0050.00

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00
< 0.005
< 0.005

0.00< 0.005< 0.0050.00
PM2.5D

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.0050,00 PM2.5T

0.003.543.260.003.343.260.002.232.140.000.370.350.00|C02e 24/50
Explorer Well v4 Detailed Report, 11/7/2023
Off-Road
Equipment
Paving
Onsite truckAverage Daily
Off-Road
EquipmentPaving
Onsite truck
AnnualOff-Road
EquipmentPavingOnsite truck
Offsite
Daily, Summer
(Max)
Daily, Winter
(Max)
WorkerVendor
HaulingAverage Daily
Worker
Vendor
Hauling
Annual
Worker
Vendor

0.63 < 0.0050.000.04< 0.0050.00

0.01< 0.0050.00

5.57 0.000.34

0.000.060.00

7.00 0.000.420.00

0.080.00

0.01 0.26 0.26 0.24 0.24 1,081

0.00 0.00< 0.005 0.02

0.00 0.00 0.00

0.02 0.01

0.00 0.00

0.01 0.0065.6

0.00 0.00 0.00 0.00 0.00 0.00< 0.005 < 0.005 < 0.005 < 0.005

0.00 0.00< 0.005 10.9

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.090.000.00

0.010.000.00< 0.0050.00

0.110.00

0.000.010.000.00< 0.0050.00

1.28 0.000.000.080.000.000.010.00

0.000.000.000.000.000.000.000.00

0.260.000.000.020.000.00< 0.0050.00

0.260.000.000.020.000.00
< 0.0050.00

0.000.000.000.000.000.000.000.00

0.060.000.00< 0.0050.000.00< 0.0050.00

0.060.000.00
< 0.005

0.000.00
< 0.0050.00
2710.000.00

16.7 0.000.002.770.00
25/50
Explorer Well v4 Detailed Report, 11/7/2023
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

3.27. Paving (2025) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location I ROG I NOx
Onsite — —
Daily, Summer — —
(Max)
Off-Road 0.60 5.34
EquipmentPaving < 0.005 —
Onsite truck 0.00 0.00Daily, Winter — —
(Max)
Off-Road 0.60 5.34
EquipmentPaving < 0.005 —
Onsite truck 0.00 0.00Average Daily — —
Off-Road 0.39 3.50
Equipment
Paving < 0.005 —Onsite truck 0.00 0.00
Annual — —
Off-Road 0.07 0.64
EquipmentPaving < 0.005 —
Onsite truck 0.00 0.00Offsite — —
I co6.980.006.980.00

4.580.000.840.00
|S02

0.010.000.010.000.010.00< 0.005

0.00 PM10E

0.230.000.230.000.15

0.000.030,00
PM10D IPM10T

0.23 0.00

0.000.000.00

0.000.230.000.150.000.03

0.00 PM2.5E IPM2.5D IPM2.5T

0.210.00

0.210.000.140.000.030.00

0.000.00

0.210.000.210.000.140.000.030.00
IC02e1,081

0.00 1,081

0.007090.00
117

0.00 26/50
Explorer Well v4 Detailed Report, 11/7/2023
Daily, Summer —
(Max)Worker
Vendor
Hauling

0.090.000.00
Daily, Winter —(Max)
Worker
VendorHauling

0.080.000.00
Average Daily —
WorkerVendor
Hauling
AnnualWorker
Vendor
Hauling

0.060.000.000.010.000.00

0.090.000.000.100.000.000.070.000.000.010.000.00

1.39 0.000.00

1.18 0.000.000.810.000.000.150.000.00

0.000.000.00

0.000.000.000.000.000.000.000.000.00

0.000.000.000.000.000.000.00

0.00 0.000.000.000.00

0.260.000.000.260.000.000.170.000.000.030.000.00

0.000.000.000.000.000.000.000.000.000.000.000.00

0.060.00

0.00 0.060.00

0.000.040.000.000.010.000.00

0.060.000.000.060.000.000.040.000.000.010.000.00
2810.000.002650.000.00
177

0.000.0029.30.000.00

3.29. Architectural Coatings (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) PM10D
Onsite —
Daily, Summer —
(Max)
Daily, Winter —
(Max)
Off-Road
Equipment

0.14 0.91 1.15 < 0.005 0.03 0.03 0.03 0.03 134
27/50
Explorer Well v4 Detailed Report, 11/7/2023
ArchitecturalCoatingsOnsite truckAverage Daily
Off-Road
EquipmentArchitecturalCoatingsOnsite truck
AnnualOff-Road
Equipment
Architectural
CoatingsOnsite truck
Offsite
Daily, Summer
(Max)
Daily, Winter
(Max)
WorkerVendorHauling
Average DailyWorker
VendorHauling
AnnualWorker
Vendor

0.030.000.01< 0.0050.00< 0.005< 0.0050.00
< 0.0050.000.00< 0.0050.000.00< 0.005

0.00 0.000.060.000.010.00
0,000.070.000.010.00

0.00< 0.0050.00< 0.005

0.00 0.00< 0.0050.00< 0.0050.00

0.000.00

0.00 0.00
< 0.0050.00< 0.0050.00

0.00 0.00 0.00 0.00< 0.005 < 0.005 8.130.00 0.00 0.00 0.00< 0.005 < 0.005 1.350.00 0.00 0.00 0.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.020.000.00< 0.0050.000.00< 0.0050.00

0.000.000.000.000.000.00

0.000.00

0.00 0.000.000.000.000.000.000.00
< 0.0050.000.00< 0.0050.000.00< 0.0050.00
< 0.0050.000.00
< 0.0050.000.00< 0.0050.00

0.000.000.000.000.000.000.000.00
< 0.0050.00

0.00< 0.0050.000.00< 0.0050.00
< 0.0050.000.00< 0.0050.000.00< 0.0050.00

3.410.000.000.210.000.000.030.00
28/50
Explorer Well v4 Detailed Report, 11/7/2023
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00

3.31. Architectural Coatings (2025) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual)

0.00 0.00 0.00 0.00
Location I ROGOnsite
Daily, Summer
(Max)
Off-Road
Equipment
ArchitecturalCoatingsOnsite truck
Daily, Winter(Max)
Off-Road
Equipment
ArchitecturalCoatingsOnsite truck
Average DailyOff-Road
EquipmentArchitecturalCoatings
Onsite truckAnnual
Off-RoadEquipment
Architectural
Coatings

0.130.030.00

0.080.02

0.000.02
< 0.005
|NOx0.88

0.00 0.88

0.000.58

0.00 0.11
I co

1.14 0.00

1.14 0.000.750.000.14
|S02 PM10E< 0.005 0.03

0.00 < 0.005 0.03
< 0.005 0.02

0.00 < 0.005 < 0.005
PM10D IPM10T

0.03 0.03

0.00 0.00 0.00 0.00

0.02 PM2.5E

0.03 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00
< 0.005 < 0.005
PM2.5D

0.00 0.030.00 0.000.02

0.00 PM2.5T

0.030.00

0.030.000.020.00< 0.005
|C02e
134

0.00 134

0.00 87.8

0.00 14.5
29/50
Explorer Well v4 Detailed Report, 11/7/2023
Onsite truck
Offsite
Daily, Summer
(Max)
Worker
VendorHauling
Daily, Winter
WorkerVendor
Hauling
Average Daily
Worker
VendorHaulingAnnual
Worker
VendorHauling

0.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00< 0.0050.000.00

0.00 < 0.0050.000.00< 0.0050.00

0.00< 0.0050.000.00< 0.0050.000.00

0.00 0.020.000.000.010.00

0.000.010.000.00< 0.0050,000.00

0.00 0.000.000.000.000.000.000.000.000.000.000.000.00

0.00 0.000.000.000.000.000.000.000.00

0.000.000.000.00

0.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.0050.00

0.00 0.00
< 0.0050.000.00< 0.005

0.00 0.00< 0.005

0.000.00< 0.0050.000.00

0.00 0.000.000.000.000.000.000.000.000.000.000.000.00

0.00 < 0.0050.00

0.00 < 0.0050.000.00
< 0.0050.000.00< 0.0050.000.00

0.00 < 0.0050.000.00< 0.0050.000.00< 0.0050.000.00< 0.005

0.000.00

0.00 3.54

0.000.00

3.34 0.000.002.230.000.000.370.000.00

3.33. Linear, Grading & Excavation (2024) - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) PM10D
Onsite —
Daily, Summer —
(Max)Off-Road
Equipment

0.24 2.40 3.83 0.01 0.11
PM10T

0.11 PM2.5D

0.10 0.10
|C02e583
30/50
Explorer Well v4 Detailed Report, 11/7/2023
Dust From —Material
Movement
Onsite truck 0.00Daily, Winter —
(Max)
Average Daily —
< 0.005 < 0.005
Off-Road
EquipmentDust From
MaterialMovement
Onsite truckAnnual
Off-Road
EquipmentDust From
MaterialMovementOnsite truck
Offsite
Daily, Summer
(Max)Worker
Vendor
Hauling
Daily, Winter(Max)
Average Daily
Worker
VendorHauling

0.070.000.010.00

0.020.00< 0.0050.010.00< 0.005

0.00 0.720.000.130.00

0.020.000.020.010.000.01

0.00 1.15

0.000.210.000.380.000.010.100.00< 0.005

0.00 < 0.0050.00< 0.0050.000.000.00< 0.0050.000.00
< 0.005

0.000.030.000.010.00

0.00< 0.0050.00< 0.0050.00

0.00 0.070.00 0.00
< 0.005 < 0.005

0.00 0.020.00 0.00
< 0.005 < 0.005
31/50

0.000.03< 0.0050.000.01
< 0.005

0.00 0.070.000.010.020.00< 0.005

0.000.03

0.000.010.000.000.00< 0.0050.000.00< 0.005
< 0.005 < 0.005

0.00 0.00

0.03 < 0.005 < 0.0050.00
< 0.005

0.000.020.00
< 0.005
< 0.0050.00
< 0.005

0.000.01< 0.0050.000.020.00< 0.005< 0.0050.00< 0.005

0.00 176

0.0029.10.00

71.7 0.00

19.5 20.70.005.88
Explorer Well v4 Detailed Report, 11/7/2023
Annual
WorkerVendor
Hauling
< 0.005 < 0.005 0.02 0.00 0.000.00 0.00 0.00 0.00 0.00< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005

0.00 0.00
< 0.005 < 0.005

0.00 < 0.0050.00 0.00< 0.005 < 0.005

3.35. Linear, Drainage, Utilities, & Sub-Grade (2024) - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) < 0.005 3.430.00 0.00< 0.005 0.97
PM10E PM10T IPM2.5E IPM2.5D IPM2.5T
Daily, Summer —
(Max)
Dust From —MaterialMovement
Onsite truck 0.00
Average Daily —
Off-Road 0.07EquipmentDust From —MaterialMovement
< 0.005 0.03< 0.005 0.01
Explorer Well v4 Detailed Report, 11/7/2023
Dust From —Material
Movement
Onsite truck
Offsite

0.00 Daily, Summer —
(Max)
Worker
Vendor
Hauling

0.020.000.00
Daily, Winter —
(Max)
Average Daily —Worker
Vendor
Hauling
AnnualWorkerVendor
Hauling

0.010.00

0.00< 0.0050.000.00

0.000.020.000.000.010.00

0.00< 0.0050.000.00

0.000.380.000.000.100.00

0.000.02

0.000.00

0.000.000.000.000.000.00

0.000.000.000.00

0.000.000.000.000,000.00

0.000.000.000.00

0.00 0.000.070.000.000.020.00

0.00 < 0.005

0.000.00

0.00 0.000.070.000.000.020.00

0.00< 0.0050.000.00

0.00 0.00 0.000.000.000.000.000.00

0.000.000.000.00

0.020.000.00< 0.0050.00

0.00< 0.0050.000.00

0.00 0.00

0.020.000.00
< 0.0050.00

0.00 < 0.0050.000.00

0.00 71.70.00

0.0020.70.00

0.00 3.430.000.00

3.37. Linear, Paving (2024) - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Location
Onsite
IROG
Daily, Summer —
(Max)
Off-Road
Equipment

0.75 |NOx

6.61 I co

8.18 |S020.01
PM10E

0.30 PM10D

0.30 PM2.5E

0.28 0.28 1,268
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Explorer Well v4 Detailed Report, 11/7/2023
Onsite truck
Daily, Winter
Average DailyOff-Road
EquipmentOnsite truck
AnnualOff-Road
Equipment
Onsite truck
Offslte
Daily, Summer
(Max)Worker
VendorHauling
Daily, Winter(N4ax)Average Daily
Worker
Vendor
HaulingAnnual
Worker
VendorHauling

0.00 0.230.000.040.000.090.000.000.03

0.000.00< 0.0050.000.00

0.00 1.99

0.000.360.000.100.000.00

0.030.000.000.010.000.00

0.00 2.470.000.450.00

1.51 0.00

0.000.400.000.000.070.000.00

0.00 < 0.0050.00< 0.0050.000.000.000.00

0.000.000.000.000.000.00

0.00 0.09

0.000.020.000.000,000.000.000.000.000.000.00

0.00 0.00

0.000.000.260.000.000.08

0.000.000.010.000.00

0.00 0.090.000.020.000.260.000.000.080.00

0.000.010.000.00

0.00 0.080.000.020.000.000.000.00

0.000.000.000.000.000.00

0.00 0.000.000.060.000.000.020.000.00< 0.0050.00

0.00 0.00

0.080.000.020.000.060.000.00

0.020.000.00< 0.0050.000.00

0.00 3820.0063.30.002870.000.0083.00.000.00

13.7 0.000.00

4. Operations Emissions Details
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4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) Vegetation IROG |NOx co S02 PM10E PM10D PM10TDaily, Summer — (Max)
Total —
Daily, Winter —
(Max)Total —
Annual —Total —

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG |NOx I co |S02 IPM10E IPM10D PM10TDaily, Summer — (Max)Total —
Daily, Winter —
(Max)
Total —
Annual —
Total —

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) 35/50
PM2.5E IPM2.5D PM2.5T C02ePM2.SE PM2.5D IPM2.5T |C02e
Explorer Well v4 Detailed Report, 11/7/2023
Species PM10D
Explorer Well v4 Detailed Report, 11/7/2023

5. Activity Data

5.1. Construction Schedule
Phase Name Phase Type I Start Date
Site
Preparation/Mobilization
Noise Barriers
Well Drilling
Well Drilling Continued
Well DevelopmentInstall Test Pump, Well
Testing and Sampling
Equipment InstallationSite Development
Building ConstructionPavingArchitectural CoatingsLinear, Grading &ExcavationLinear, Drainage, Utilities, &Sub-Grade Linear, Paving
Site Preparation 4/1/2024
Site Preparation 4/23/2024
Site Preparation 5/23/2024Site Preparation 6/21/2024Building Construction 7/19/2024 Building Construction 8/1/2024
Building Construction 12/1/2024Building Construction 12/1/2024 Building Construction 12/1/2024Paving 12/1/2024Architectural Coating 12/1/2024Linear, Grading & 4/1/2024 Excavation
Linear, Drainage, Utilities, & 4/1/2024
Sub-GradeLinear, Paving 4/1/2024

5.2. Off-Road Equipment

5.2.1.unmiti9ated
End Date
4/22/2024
7/23/20246/20/20247/18/20247/31/2024
8/29/2024
12/1/2025
12/1/2025
12/1/202512/1/202512/1/2025
9/1/2024
9/1/20249/1/2024
Days Per Week

5.005.007.00

7.007.00

5.005.005.00

5.005.005.005.005.005.00
Work Days per Phase | Phase Description

16.0 66.029.0

18.013.0

21.0 261
261
261261
261
110
110
110
Phase Name Equipment Type Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor 37/50
Explorer Well v4 Detailed Report, 11/7/2023
Site
Preparation/Mobilization
Site
Preparation/Mobilization
Site
Preparation/MobilizationNoise Barriers
Tractors/Loaders/Backh Dieseloes
Bore/Drill RigsCranes
DieselDiesel
Tractors/Loaders/Backh Diesel
oes
Noise Barriers
Well DrillingWell DrillingWell Drilling
Well Drilling
Well Drilling ContinuedWell Drilling Continued
Well Drilling Continued
Well Drilling Continued
Well DevelopmentWell DevelopmentWell DevelopmentWell DevelopmentInstall Test Pump, WellTesting and SamplingEquipment InstallationEquipment Installation Site Development
Bore/Drill Rigs
Bore/Drill RigsAir CompressorsPumps
Rough Terrain Forklifts
Tractors/Loaders/Backh
oesBore/Drill RigsPumps
Generator Sets
Tractors/Loaders/BackhoesBore/Drill Rigs
Pumps
Generator SetsPumps
DieselDieselDieselDiesel
Diesel
DieselDiesel
DieselDiesel
DieselDieselDieselDieselDiesel
Tractors/Loaders/Backh Dieseloes
Bore/Drill Rigs
Tractors/Loaders/Backhoes
Diesel
Diesel
AverageAverageAverage
Average
AverageAverageAverageAverage
AverageAverageAverageAverage
AverageAverageAverageAverageAverageAverageAverageAverage Average

1.001.001.00

2.00 1.001.001.001.00

1.00 2.00

1.001.00
1,001.001.001.001.001.00

2.00 1.00

2.00 8.008.008.00

8.00 8.0024.024.024.0

8.0024.0

24.024.024.024.024.024.024.08.008.008.008.00

84.083.036784.083.083.037.0

11.0 96.084.083.011.014.0

84.083.0

11.014.011.0

84.083.084.0

0.370.500.290.370.500.500.480.74

0.400.370.500.740.740.370.500.740.740.740.370.500.37
38/50
Explorer Well v4 Detailed Report, 11/7/2023
Building Construction
Paving
Paving
Paving
Paving
Tractors/Loaders/Backh
oes
Cement and Mortar
Mixers
Pavers
Rollers
Tractors/Loaders/Backh
oes
Architectural Coatings Air Compressors
Linear, Grading &Excavation
Linear, Drainage,
Utilities, & Sub-GradeLinear, Paving
Linear, Paving
Linear, Paving
Linear, Paving
Tractors/Loaders/Backh
oes
Tractors/Loaders/BackhoesTractors/Loaders/Backhoes
Cement and Mortar
Mixers
RollersPavers
Diesel
Diesel
Diesel
Diesel
Diesel
DieselDiesel
Diesel
Diesel
Diesel
Diesel
Diesel

5.3. Construction Vehicles

5.3.1. Unmitigated
Phase Name I Trip Type
Site Preparation/Mobilization —
Site Preparation/Mobilization Worker
Site Preparation/Mobilization VendorSite Preparation/Mobilization HaulingSite Preparation/Mobilization Onsite truck Well Drilling Continued —
AverageAverageAverage
Average
Average
Average
Average
Average
Average
AverageAverageAverage

2.004.00

1.00 1.00

2.00 1.00

2.00 2.002.00

4.00 1.001.00

8.006.007.00

7.007.00

6.008.00

8.008.00

8.008.008.00

84.0 10.0

81.0 36.084.037.084.0

84.084.0

10.0 36.0

81.0 0.370.560.42

0.380.37

0.48 0.37

0.370.37

0.560.380.42
One-Way Trips per Day

7.502.00
Miles per Trip

18.510.2

20.0 I Vehicle Mb(
LDA,LDT1,LDT2HHDT.MHDT
HHDT
HHDT
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Explorer Well v4 Detailed Report, 11/7/2023
Well Drilling Continued Worker
Well Drilling Continued Vendor
Well Drilling Continued Hauling
Well Drilling Continued Onsite truck
Paving —
Paving WorkerPaving VendorPaving HaulingPaving Onsite truckLinear, Grading & Excavation —Linear. Grading & Excavation WorkerLinear, Grading S Excavation Vendor Linear, Grading & Excavation Hauling
Linear, Grading & Excavation Onsite truck
Linear, Drainage, Utilities, & Sub-Grade —
Linear, Drainage, Utilities, & Sub-Grade WorkerLinear, Drainage, Utilities, & Sub-Grade VendorLinear, Drainage, Utilities, & Sub-Grade HaulingLinear, Drainage, Utilities, & Sub-Grade Onsite truck Linear, Paving —
Linear, Paving WorkerLinear, Paving VendorLinear, Paving Hauling Linear, Paving Onsite truck
Noise Barriers —Noise Barriers Worker
Noise Barriers Vendor

12.5 2.1120.00.005.000.000.265.000.000.00

20.00.000.00

7.50 18.510.2

20.0 18.510.2

20.018.510.2
LDA,LDT1,LDT2HHDT.MHDTHHDTHHDTLDA,LDT1,LDT2HHDT.MHDTHHDT HHDT
LDA.LDT1.LDT2HHDT.MHDTHHDTHHDTLDA,LDT1,LDT2HHDT.MHDTHHDTHHDTLDA,LDT1,LDT2HHDT.MHDTHHDTHHDTLDA,LDT1,LDT2 HHDT.MHDT
40/50
Explorer Well v4 Detailed Report, 11/7/2023
Noise Barriers HaulingNoise Barriers Onsite truck
Well Drilling —Well Drilling Worker
Well Drilling Vendor
Well Drilling HaulingWell Drilling Onsite truck
Well Development —Well Development Worker
Well Development Vendor
Well Development HaulingWell Development Onsite truck
Install Test Pump, Well Testing and —
Sampling
Install Test Pump, Well Testing and Worker
Sampling
Install Test Pump, Well Testing and VendorSamplingInstall Test Pump, Well Testing and Hauling Sampling
Install Test Pump, Well Testing and Onsite truck
Sampling
Equipment Installation —
Equipment Installation WorkerEquipment Installation Vendor Equipment Installation Hauling
Equipment Installation Onsite truckSite Development —Site Development Worker

0.00 10.0

0.66 0.250.10

0.000.250.100.00

20.0 18.5

10.2 20.0

18.510.2

20.0 18.510.2

20.0 0.250.100.000.25

18.510.2

20.0 18.5
HHDT
HHDTLDA.LDT1.LDT2HHDT.MHDTHHDT
HHDT
LDA,LDT1,LDT2HHDT.MHDT
HHDTHHDTLDA,LDT1,LDT2HHDT.MHDTHHDTHHDTLDA.LDT1.LDT2HHDT.MHDTHHDT HHDTLDA,LDT1,LDT2
41/50
Explorer Well v4 Detailed Report, 11/7/2023
Site DevelopmentSite DevelopmentSite DevelopmentBuilding Construction Building Construction
Building ConstructionBuilding ConstructionBuilding Construction Architectural CoatingsArchitectural CoatingsArchitectural CoatingsArchitectural CoatingsArchitectural Coatings Vendor
HaulingOnsite truck
Worker
Vendor
HaulingOnsite truck
Worker
VendorHauling
Onsite truck

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies
Non-applicable. No control strategies activated by user.

5.5. Architectural Coatings

0.100.000.25

0.100.000.250.00

10.2 20.0

18.5 10.2

20.0 18.510.2

20.0 HHDT.MHDTHHDTHHDT
LDA,LDT1,LDT2
HHDT.MHDTHHDTHHDTLDA,LDT1,LDT2HHDT.MHDTHHDTHHDT
Phase Name Residential Interior Area Coated I Residential Exterior Area Coated I Non-Residential Interior Area I (sq ft) | (sq ft) | Coated (sq ft)
Architectural Coatings 0.00

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities

0.00 900
Non-Residential Exterior Are
Coated (sq ft)
300
Parking Area Coated (sq ft)
585
Phase Name Material Imported (Cubic Yards) | Material Exported (Cubic Yards) | Acres Graded (acres) Material Demolished (sq. ft.) | Acres Paved (acres) 42/50
Explorer Well v4 Detailed Report, 11/7/2023
Site Preparation/Mobilization — 250Well Drilling — 150
Well Drilling Continued — 300Paving 0.00 0.00Linear, Grading & Excavation — 230 Linear, Drainage, Utilities, & — —
Sub-Grade

5.6.2. Construction Earthmoving Control Strategies
Control Strategies Applied Frequency(per day)

0.000.00

0.000.000.020.02
PM 10 Reduction

0.000.00

0.000.000.000.00

0.24 Water Exposed AreaWater Demolished Area
22 61%
36%
PM2.5 Reduction
61%36%

5.7. Construction Paving
Land Use
Other Asphalt SurfacesUser Defined Industrial
User Defined Linear
[Area Paved (acres)0.220.000.02
% Asphalt
100%
0%
100%

5.8. Construction Electricity Consumption and Emissions FactorskWh per Year and Emission Factor (Ib/MWh) Year
20242025
I kWh per Year0.000.00
|C02
1,0281,028
CH4

0.030.03
I N20< 0.005< 0.005

5.18. Vegetation
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Explorer Well v4 Detailed Report, 11/7/2023

5.18.1. Land Use Change

5.18.1.1. Unmitigated
Vegetation Land Use Type

5.18.1. Biomass Cover Type

5.18.1.1.unmiti9ated
Biomass Cover Type

5.18.2. Sequestration

5.18.2.1. Unmitigated
Tree Type
Vegetation Soil Type Initial Acres Final Acres
Initial Acres Final Acres
Number Electricity Saved (kWh/year) Natural Gas Saved (btu/year)

6. Climate Risk Detailed Report

6.1. Climate Risk Summary
Cal-Adapt midcentury 2040-2059 average projections for four hazards are reported below for your project location. These are under Representation Concentration Pathway (RCP) 8.5 which assumes GHG emissions will continue to rise strongly through 2050 and then plateau around 2100.

Climate Hazard
Temperature and Extreme Heat
Extreme Precipitation
Sea Level Rise
Wildfire
Result for Project Location

25.8 10.0

0.00 28.2
I Unitannual days of extreme heat
annual days with precipitation above 20 mmmeters of inundation depth annual hectares burned
Temperature and Extreme Heat data are for grid cell in which your project are located. The projection is based on the 98th historical percentile of daily maximum/minimum temperatures from observedhistorical data (32 climate model ensemble from Cal-Adapt, 2040-2059 average under RCP 8.5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi. 44/50
Explorer Well v4 Detailed Report, 11/7/2023
Extreme Precipitation data are for the grid cell in which your project are located. The threshold of 20 mm is equivalent to about % an inch of rain, which would be light to moderate rainfall if received over a fullday or heavy rain if received over a period of 2 to 4 hours. Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Users may select from four scenarios to view the range in potential inundation depth for the grid cell. The four scenarios are: No rise, 0.5 meter, 1.0 meter, 1 .41 meters Wildfire data are for the grid cell in which your project are located. The projections are from UC Davis, as reported in Cal-Adapt (2040-2059 average under RCP 8.5), and consider historical data of climate,vegetation, population density, and large (> 400 ha) fire history. Users may select from four model simulations to view the range in potential wildfire probabilities for the grid cell. The four simulations makedifferent assumptions about expected rainfall and temperature are: Warmer/drier (HadGEM2-ES), Cooler/wetter (CNRM-CM5), Average conditions (CanESM2), Range of different rainfall and temperaturepossibilities (MIROC5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

6.2. Initial Climate Risk Scores
Climate HazardTemperature and Extreme Heat
Extreme PrecipitationSea Level RiseWildfireFloodingDrought Snowpack ReductionAir Quality Degradation
Exposure Score
3 N/A11N/A
N/AN/A0
Sensitivity Score
0N/A00

N/AN/AN/A
0 I Adaptive Capacity Score
0N/A00N/A
N/A
N/A0
Vulnerability ScoreN/AN/A
N/A

N/AN/AN/AN/A
N/A
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatestexposure.The adaptive capacity of a project refers to Its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing the greatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores do not include implementation of climate risk reduction measures.

6.3. Adjusted Climate Risk Scores
Climate Hazard
Temperature and Extreme Heat
Extreme PrecipitationSea Level Rise
Wildfire
Exposure Score
3 N/A1
1 I Sensitivity Score
1 N/A1
1 I Adaptive Capacity Score1
N/A
11 \Ajlnerability Score
3N/A2
2 45/50
Explorer Well v4 Detailed Report, 11/7/2023
Flooding
DroughtSnowpack Reduction
Air Quality Degradation
N/A
N/AN/A1
N/A
N/AN/A
1 N/A
N/AN/A1
N/A
N/AN/A
2 The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.

The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing the greatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores include implementation of climate risk reduction measures.

6.4. Climate Risk Reduction Measures

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 ScoresThe maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.

Indicator
Exposure IndicatorsAQ-Ozone

AQ-PMAQ-DPM
Drinking WaterLead Risk HousingPesticides
Toxic ReleasesTraffic
Effect Indicators
Cleanup Sites
Groundwater
Result for Project Census Tract

82.655.434.575.4

72.7 0.0063.727.768.963.4
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Explorer Well v4 Detailed Report, 11/7/2023
Haz Waste Facilities/Generators
Impaired Water Bodies
Solid Waste
Sensitive Population
Asthma
Cardio-vascularLow Birth WeightsSocioeconomic Factor IndicatorsEducationHousing Linguistic
PovertyUnemployment

43.3 23.9

36.526.0

7.99 65.847.6

58.257.836.4

7.2. hlealthy Places Index Scores
The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

Indicator
Economic
Above Poverty
Employed
Median HI
Education
Bachelor's or higher
High school enrollmentPreschool enrollmentTransportation Auto Access
Result for Project Census Tract
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Explorer Well v4 Detailed Report, 11/7/2023
Active commuting
Social2-parent householdsVoting
Neighborhood
Alcohol availabilityPark access
Retail density
Supermarket accessTree canopyHousingHomeownershipHousing habitability Low-inc homeowner severe housing cost burden
Low-inc renter severe housing cost burdenUncrowded housingHealth OutcomesInsured adults ArthritisAsthma ER Admissions
High Blood PressureCancer (excluding skin)AsthmaCoronary Heart DiseaseChronic Obstructive Pulmonary DiseaseDiagnosed DiabetesLife Expectancy at Birth

11.1 69.4

3.7 18.5

40.2 15.5

40.0 10.7

0.0 48/50
Explorer Well v4 Detailed Report, 11/7/2023
Cognitively Disabled
Physically DisabledHeart Attack ER AdmissionsMental Health Not GoodChronic Kidney DiseaseObesity Pedestrian Injuries
Physical Health Not GoodStrokeHealth Risk BehaviorsBinge Drinking Current Smoker
No Leisure Time for Physical ActivityClimate Change Exposures Wildfire Risk
SLR Inundation Area
Children
ElderlyEnglish SpeakingForeign-bornOutdoor Workers
Climate Change Adaptive Capacity
Impervious Surface CoverTraffic Density
Traffic Access
Other Indices
Hardship

66.4 42.3

88.5 62.3

10.6 34.9

0.043.5

7.6 89.1

70.954.125.0

0.0 40.539.0

0.00.091.484.20.0

23.0 0.0
49/50
Explorer Well v4 Detailed Report, 11/7/2023
Other Decision Support
2016 Voting 0.0

7.3. Overall Health & Equity Scores
Metric
CalEnviroScreen 4.0 Score for Project Location (a)Healthy Places Index Score for Project Location (b) Project Located in a Designated Disadvantaged Community (Senate Bill 535) Project Located in a Low-lncome Community (Assembly Bill 1550)Project Located in a Community Air Protection Program Community (Assembly Bill 617) Result for Project Census Tract

43.0 No
NoNo
a: The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.b: The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

7.4. Health & Equity Measures
No Health & Equity Measures selected.

7.5. Evaluation Scorecard
Health S Equity Evaluation Scorecard not completed.

7.6. Health & Equity Custom Measures
No Health & Equity Custom Measures created.

8. User Changes to Default Data
Screen
Characteristics: Project Details
Land Use
Construction: Construction Phases
Construction: Off-Road Equipment
Construction: Dust From Material Movement
Justification
Suburban AreaData provided by applicant.Data Provided by ApplicantData Provided by applicant Data Provided by Applicant
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Explorer Well v3 Detailed Report, 11/7/2023
Explorer Well v3 Detailed Report
Table of Contents

1. Basic Project Information

1.1. Basic Project Information1.2. Land Use Types1.3. User-Selected Emission Reduction Measures by Emissions Sector

2. Emissions Summary

2.4. Operations Emissions Compared Against Thresholds

2.5. Operations Emissions by Sector, Unmitigated

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated

4.2.3. Natural Gas Emissions By Land Use - Unmitigated

4.3. Area Emissions by Source
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Explorer Well v3 Detailed Report, 11/7/2023

4.3.1. Unmitigated

4.4. Water Emissions by Land Use

4.4.1. Unmitigated

4.5. Waste Emissions by Land Use

4.5.1. Unmitigated

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated

4.7. Offroad Emissions By Equipment Type

4.7.1. Unmitigated

4.8. Stationary Emissions By Equipment Type

4.8.1. Unmitigated

4.9. User Defined Emissions By Equipment Type

4.9.1. Unmitigated

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated 2/27
Explorer Well v3 Detailed Report, 11/7/2023

5. Activity Data

5.9. Operational Mobile Sources

5.9.1. Unmitigated

5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated

5.10.2. Architectural Coatings

5.10.3. Landscape Equipment

5.11. Operational Energy Consumption

5.11.1. Unmitigated

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated

5.13. Operational Waste Generation

5.13.1. Unmitigated

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated

5.15. Operational Off-Road Equipment
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5.15.1.unmitioated

5.16. Stationary Sources

5.16.1. Emergency Generators and Fire Pumps5.16.2. Process Boilers

5.17. User Defined5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated

5.18.2. Sequestration

5.18.2.1. Unmitigated

6. Climate Risk Detailed Report

6.1. Climate Risk Summary

6.2. Initial Climate Risk Scores

6.3. Adjusted Climate Risk Scores6.4. Climate Risk Reduction Measures 4/27
Explorer Well v3 Detailed Report, 11/7/2023

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores7.2. hlealthy Places Index Scores

7.3. Overall Health & Equity Scores

7.4. Health & Equity Measures7.5. Evaluation Scorecard

7.6. Health & Equity Custom Measures

8. User Changes to Default Data
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Explorer Well v3 Detailed Report, 11/7/2023

1. Basic Project Information

1.1. Basic Project Information
Data Field
Project NameOperational YearLead AgencyLand Use ScaleAnalysis Level for Defaults Windspeed (m/s)
Precipitation (days)LocationCounty
CityAir District
Air BasinTAZ
EDFZElectric UtilityGas UtilityApp Version

1.2. Land Use Types
Land Use Subtype | Size
Other AsphaltSurfaces
g.75
Unit
1000sqft
Lot Acreage

0.22 lvalue
Explorer Well v3
2026Project/site
County

2.505.20
Explorer Rd, Pasadena, CA, USALos Angeles-South CoastPasadenaSouth Coast AQMDSouth Coast 4930
7 Pasadena Water & PowerSouthern California Gas
2022.1.1.20
Building Area (sq ft) j Landscape Area (sq | Special Landscape | Population I ft) I Area (sq ft)

0.00 6/27
Description
Explorer Well v3 Detailed Report, 11/7/2023
User Defined
Industrial
600
User Defined Linear 0.1 5
User Defined Unit 0.15
Mile 0.02
600

0.00 0.00

1.3. User-Selected Emission Reduction Measures by Emissions Sector No measures selected

2. Emissions Summary

2.4. Operations Emissions Compared Against ThresholdsCriteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Un/Mit. IROG
Daily, Summer —
(Max)
Un mit. 0.03
Daily, Winter —
(Max)
Unmit. 0.02Average Daily —
(Max)
Unmit. 0.03
Annual (Max) —Unmit. < 0.005
iNOx0.010.01

0.01< 0.005
I co0.110.080.080.02
|S02 IPM10E PM10D< 0.005 < 0.005 0.02< 0.005 < 0.005 0.02< 0.005 < 0.005 0.02 IPM10T0.020.020.02
< 0.005 < 0.005 < 0.005 < 0.005

2.5. Operations Emissions by Sector, Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) PM10E PM10D
Daily, Summer —
(Max)
IPM2.5E
< 0.005< 0.005< 0.005< 0.005
IPM2.5D< 0.005< 0.005< 0.005< 0.005
[PM2.5T< 0.005< 0.005< 0.005< 0.005
PM2.5D IPM2.5T
|C02e292291288

47.7 7/27
Explorer Well v3 Detailed Report, 11/7/2023
Mobile
Area
Energy
WaterWasteTotal
Daily, Winter
(Max)
MobileArea
Energy
WaterWasteTotal
Average Daily
Mobile
AreaEnergy
WaterWasteTotal
Annual
MobileArea
Energy
WaterWasteTotal

0.01 0.020.000.030.010.020.000.020.010.020.000.03< 0.005< 0.0050.00< 0.005

0.01 < 0.0050.000.010.010.000.010.01< 0.0050.00

0.01< 0.005< 0.0050.00< 0.005

0.08 0.030.000.110.080.00

0.080.070.020.000.080.01< 0.0050.000.02
< 0.005
< 0.0050.00< 0.005< 0.005

0.00 < 0.005
< 0.005< 0.0050.00< 0.005< 0.005< 0.0050.00< 0.005
< 0.005
< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005< 0.0050.00< 0.005< 0.005 < 0.0050.00< 0.005

0.02 0.020.020.020.02

0.02< 0.005< 0.005
8/27

0.02 < 0.0050.000.020.020.000.020.02< 0.0050.00

0.02< 0.005< 0.0050.00< 0.005
< 0.005
< 0.0050.00< 0.005< 0.0050.00
< 0.005< 0.005< 0.0050.00< 0.005< 0.005< 0.0050.00< 0.005 < 0.005
< 0.005< 0.005< 0.005< 0.005
< 0.005< 0.005< 0.005
< 0.005
< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005< 0.0050.00< 0.005< 0.005< 0.0050.00< 0.005

21.2 0.112710.000.0029220.32710.000.00291

17.6 0.072710.000.002882.910.01

44.8 0.000.0047.7
Explorer Well v3 Detailed Report, 11/7/2023

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG
Daily, Summer —
(Max)
Other Asphalt 0.00
Surfaces
User Defined 0.01Industrial
Total 0.01
Daily, Winter —
(Max)Other Asphalt 0.00
SurfacesUser Defined 0.01
Industrial
Total
Annual

0.01 Other Asphalt 0.00SurfacesUser Defined < 0.005
Industrial
Total < 0.005
|NOx I co

0.00 0.000.01 0.080.01 0.080.000.010.010.00< 0.005
< 0.005

0.000.080.080.000.010.01
|S020.00
< 0.005
< 0.0050.00
< 0.005< 0.005
IPM10E0.00< 0.005< 0.0050.00
< 0.005< 0.005

0.00 0.00< 0.005 < 0.005< 0.005 < 0.005
IPM10D

0.000.020.020.00

0.020.020.00< 0.005< 0.005
PM10T

0.000.020.020.000.020.02
PM2.SE

0.00< 0.005< 0.0050.00
< 0.005< 0.005

0.00 0.00< 0.005 < 0.005< 0.005 < 0.005
PM2.5D

0.00< 0.005< 0.0050.00< 0.005< 0.0050.00< 0.005< 0.005
PM2.5T

0.00 < 0.005< 0.0050.00
< 0.005
< 0.005
[C02e

0.00 0.00
< 0.005 21.2< 0.005 21.2

0.0020.320.30.002.912.91

4.2. Energy
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4.2.1. Electricity Emissions By Land Use - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG |NOx I co S02 PM10E PM10D 'M10T PM2.5E PM2.5D IPM2.5T Daily, Summer —
(Max)
User Defined —Industrial
Total —Daily, Winter —(Max)
User Defined —Industrial
Total —
Annual —User Defined —Industrial
Total —
iC02e 271 271 271
27144.844.8

4.2.3. Natural Gas Emissions By Land Use - Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use ROG
Daily, Summer —
(Max)
User DefinedIndustrial
Total

0.000.00
Daily, Winter —(Max)
User Defined
Industrial

0.00 NOx

0.000.000.00
co

0.000.000.00
S02 PM10E PM10D

0.00 0.000.00 0.00

0.00 0.00
PM10T

0.000.000.00
PM2.5E

0.000.000.00
PM2.5D PM2.5T

0.000.000.00
C02e

0.000.00

0.00 10/27
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Total
Annual

0.00 User Defined 0.00
Industrial
Total 0.00

0.00 0.00

0.000.00

0.00 0.000.00

4.3. Area Emissions by Source

4.3.1. Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Source IROG
Daily, Summer —
(Max)
ConsumerProducts
Architectural
CoatingsLandscape
Equipment
Total

0.01< 0.005< 0.0050.02
Daily, Winter —
(Max)
ConsumerProductsArchitecturalCoatings
Total
Annual
Consumer
Products

0.01< 0.0050.02< 0.005
|NOx co< 0.005< 0.005

0.030.03
|S02 PM10E IPM10D PM10T
< 0.005 < 0.005
< 0.005 < 0.005
< 0.005< 0.005

0.00 0.000.00

0.00 0.000.00
PM2.5E PM2.5D PM2.5T C02e
< 0.005< 0.005
< 0.005
< 0.005

0.110.11
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Architectural < 0.005 _ _ _ _
CoatingsLandscape < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 Equipment
Total < 0.005 < 0.005 < 0.005 < 0.005 < 0.005
< 0.005< 0.005

4.4. Water Emissions by Land Use4.4.1. Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG
Daily, Summer —
(Max)Other Asphalt —
SurfacesUser Defined —
Industrial
Total —
Daily, Winter —
(Max)
Other Asphalt —
Surfaces
User Defined —Industrial
Total —
Annual —
Other Asphalt —
SurfacesUser Defined —Industrial
Total —
|NOx I co |S02 IPM10E IPM10D IPM10T
< 0.005< 0.005
< 0.005< 0.005

0.010.01
PM2.5E PM2.5D PM2.5T C02e

0.000.00

0.000.000.000.000,000.000.00
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4.5. Waste Emissions by Land Use

4.5.1. Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG NOx I co |S02 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T Daily, Summer
(Max)
Other AsphaltSurfaces
User DefinedIndustrialTotal
Daily, Winter
(Max)
Other AsphaltSurfacesUser DefinedIndustrialTotalAnnual
Other Asphalt
Surfaces
User Defined
Industrial
Total

4.6. Refrigerant Emissions by Land Use4.6.1. UnmitigatedCriteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) 13/27
C02e

0.000.000.00

0.000.000.00
Explorer Well v3 Detailed Report, 11/7/2023
Land Use I ROG N Ox co S02 PM10E PM10D PM10' PM2.5E PM2.5D PM2.5T |C02e Daily, Summer — — —
(Max)Total _ _ _Daily, Winter — — —(Max)
Total — — _
Annual — — —
Total — _ _

4.7. Offroad Emissions By Equipment Type

4.7.1. Unmitigated
Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) EquipmentType
Daily, Summer —
(Max)
IROG |NOx I co S02
I
PM10E PM10D PM10T
Total —
Daily, Winter —
(Max)Total —
Annual —Total —

4.8. Stationary Emissions By Equipment Type4.8.1. Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) 14/27
PM2.5E IPM2.5D IPM2.5T C02e
Explorer Well v3 Detailed Report, 11/7/2023
Equipment I ROGType
|NOx co |S02 PM10E PM10D PM10T IPM2.SE PM2.5D PM2.5T |C02e Daily, Summer — — — — _ _ _
(Max)
Total _______
Daily, Winter — — — — — — —
(Max)Total __—————
Annual — — — — — — —
Total ___————

4.9. User Defined Emissions By Equipment Type4.9.1. UnmitigatedCriteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Equipment | ROGType
NOx I co |S02 PM10E IPM10D IPM10T |PM2.5E IPM2.5D PM2.5T |C02e Daily, Summer —
(Max)Total —
Daily, Winter —
(Max)Total —
Annual —
Total —

4.10. Soil Carbon Accumulation By Vegetation Type4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) 15/27
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Vegetation IROG NOx |S02 PM10E PM10D PM10T
Daily, Summer ——————
(Max)Total ______
Daily, Winter ——————
(Max)Total —_—__—
Annual ____——
Total ______

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated Criteria Pollutants (Ib/day for daily, ton/yr for annual) and GHGs (Ib/day for daily, MT/yr for annual) Land Use IROG |NOx I co [S02 IPM10E IPM10D IPM10T
Daily, Summer — — — ——
(Max)Total — — — — —
Daily, Winter — — — ——
(Max)Total _ _ __ _
Annual — — __ _Total _ _ —_ _

4.10.3. Avoided and Sequestered Emissions by Species - UnmitigatedCriteria Pollutants (Ib/day for daily, ton/yrfor annual) and GHGs (Ib/day for daily, MT/yrfor annual) Species
Daily, Summer —
(Max)Avoided —
Subtotal —
PM10E PM10D
16/27
PM2.5E PM2.5D PM2.5T C02ePM2.5E IPM2.5D IPM2.5T |C02e
Explorer Well v3 Detailed Report, 11/7/2023
SequesteredSubtotal
Removed
Subtotal
Daily, Winter
(Max)Avoided
Subtotal
Sequestered
SubtotalRemovedSubtotalAnnual
Avoided
SubtotalSequesteredSubtotalRemovedSubtotal

5. Activity Data

5.9. Operational Mobile Sources5.9.1. Unmitigated
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Land Use Type [TripsA/Veekday
Other AsphaltSurfaces
User DefinedIndustrial

0.00 2.40
Trips/Saturday

0.002.40
Trips/Sunday

0.000.00
Trips/Year

0.00751
VMT/Weekday | VMT/Saturday IVMT/Sunday

0.0026.6

0.000.00
VMT/Year

0.008,335

5.10. Operational Area Sources

5.10.1. Hearths5.10.1.1. Unmitigated

5.10.2. Architectural Coatings
Residential Interior Area Coated (sq ft) | Residential Exterior Area Coated (sq ft) | Non-Residentiaf Interior Area Coated I (sq ft)
0 0.00

5.10.3. Landscape Equipment
goo
Non-Residential Exterior Area Coated | Parking Area Coated (sq ft) I (sq ft)
300 585
Snow DaysSummer Days
day/yrday/yr

5.11. Operational Energy Consumption

5.11.1.unmiti9atedElectricity (RWh/yr) and C02 and CH4 and N20 and Natural Gas (kBTU/yr) Land Use
User Defined Industrial
Electricity (kWh/yr)

0.00250
Explorer Well v3 Detailed Report, 11/7/2023

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated
Land Use Indoor Water (gal/year)
Other Asphalt Surfaces
User Defined Industrial

0.000.00

5.13. Operational Waste Generation

5.13.1. Unmitigated
Land Use
Other Asphalt SurfacesUser Defined Industrial
Waste (ton/year)

0.000.00

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated
Outdoor Water (gal/year)

0.000.00
I Cogeneration (RWh/year)
Land Use Type Equipment Type Refrigerant GWP Quantity (kg) Operations Leak Rate | Service Leak Rate | Times Serviced

5.15. Operational Off-Road Equipment

5.15.1. Unmitigated
Equipment Type I Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor

5.16. Stationary Sources

5.16.1. Emergency Generators and Fire Pumps
19/27
Equipment Type Fuel Type

5.16.2. Process Boilers
Equipment Type

5.17. User Defined
Equipment Type

5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated
Vegetation Land Use Type

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated
Biomass Cover Type

5.18.2. Sequestration

5.18.2.1. Unmitigated
Tree Type
Fuel Type
Number per Day
Number
Vegetation Soil TypeNumber

6. Climate Risk Detailed Report
Explorer Well v3 Detailed Report, 11/7/2023
Hours per Day Hours per Year Horse Dower Load Factor
Boiler Rating (MMBtu/hr) | Daily Heat Input (MMBtu/day) ] Annual Heat Input (MMBtu/yr) I Fuel Type
Initial Acres
Electricity Saved (kWh/year)
Final Acres
Final Acres
Natural Gas Saved (btu/year)
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Climate Hazard
Temperature and Extreme Heat
Extreme Precipitation
Sea Level Rise
Wildfire
Result for Project Location

25.8 10.0

0.0028.2
I Unit
annual days of extreme heat
annual days with precipitation above 20 mmmeters of inundation depthannual hectares burned Temperature and Extreme Heat data are for grid cell in which your project are located. The projection is based on the 98th historical percentile of daily maximum/minimum temperatures from observedhistorical data (32 climate model ensemble from Cal-Adapt, 2040-2059 average under RCP 8.5). Each grid cell Is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.Extreme Precipitation data are for the grid cell in which your project are located. The threshold of 20 mm is equivalent to about % an inch of rain, which would be light to moderate rainfall if received over a full day or heavy rain if received over a period of 2 to 4 hours. Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Sea Level Rise data are for the grid cell in which your project are located. The projections are from Radke et al. (2017), as reported in Cal-Adapt (Radke et al., 2017, CEC-500-2017-008), and consider inundation location and depth for the San Francisco Bay, the Sacra mento-San Joaquin River Delta and California coast resulting different increments of sea level rise coupled with extreme storm events.Users may select from four scenarios to view the range in potential inundation depth for the grid cell. The four scenarios are: No rise, 0.5 meter, 1.0 meter, 1 .41 meters Wildfire data are for the grid cell in which your project are located. The projections are from UC Davis, as reported in Cal-Adapt (2040-2059 average under RCP 8.5), and consider historical data of climate,vegetation, population density, and large (> 400 ha) fire history. Users may select from four model simulations to view the range in potential wildfire probabilities for the grid cell. The four simulations makedifferent assumptions about expected rainfall and temperature are: Warmer/drier (HadGEM2-ES), Cooler/weHer (CNRM-CM5), Average conditions (CanESM2), Range of different rainfall and temperaturepossibilities (MIROC5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

6.2. Initial Climate Risk Scores
Climate Hazard
Temperature and Extreme HeatExtreme PrecipitationSea Level RiseWildfireFloodingDrought Snowpack Reduction
Air Quality Degradation
Exposure Score
3N/A11N/AN/AN/A
0 Sensitivity Score
0 N/A
00 N/AN/A
N/A0
I Adaptive Capacity Score
0N/A00N/AN/AN/A0
Vulnerability ScoreN/AN/A
N/A

N/AN/AN/A
N/AN/A
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The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure Is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing thegreatest ability to adapt.The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores do not include implementation of climate risk reduction measures.

6.3. Adjusted Climate Risk Scores
Climate Hazard
Temperature and Extreme Heat
Extreme PrecipitationSea Level Rise
Wildfire
Flooding
Drought
Snowpack ReductionAir Quality Degradation
Exposure Score
3 N/A11N/AN/A
N/A
1 Sensitivity Score
1 N/A
11 N/AN/AN/A
1 Adaptive Capacity Score
1N/A1
1 N/AN/AN/A1
Vulnerability Score
3N/A
22 N/AN/AN/A
2 The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatestexposure.The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing thegreatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores include implementation of climate risk reduction measures.

6.4. Climate Risk Reduction Measures7. Health and Equity Details7.1. CalEnviroScreen 4.0 Scores The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.

Indicator
Exposure Indicators
AQ-Ozone
Result for Project Census Tract

82.6 22/27
Explorer Well v3 Detailed Report, 11/7/2023
AQ-PM
AQ-DPM
Drinking Water
Lead Risk Housing
PesticidesToxic ReleasesTraffic
Effect Indicators
Cleanup SitesGroundwaterHaz Waste Facilities/Generators Impaired Water Bodies
Solid WasteSensitive Population
AsthmaCardio-vascularLow Birth Weights
Socioeconomic Factor Indicators
EducationHousing
LinguisticPoverty
Unemployment

55.4 34.575.472.70.0063.727.768.963.4

43.3 23.936.526.0

7.99 65.8

47.6 58.257.836.4

Indicator Result for Project Census Tract
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Economic
Above Poverty
Employed
Median HI
EducationBachelor's or higherHigh school enrollmentPreschool enrollmentTransportation Auto AccessActive commutingSocial
2-parent households
Voting
Neighborhood
Alcohol availability
Park access
Retail density
Supermarket accessTree canopyHousing
HomeownershipHousing habitabllity
Low-inc homeowner severe housing cost burden
Low-inc renter severe housing cost burdenUncrowded housingHealth Outcomes 24/27
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Insured adultsArthritis
Asthma ER Admissions
High Blood Pressure
Cancer (excluding skin)
AsthmaCoronary Heart DiseaseChronic Obstructive Pulmonary Disease Diagnosed Diabetes
Life Expectancy at BirthCognitively DisabledPhysically Disabled Heart Attack ER Admissions
Mental Health Not Good
Chronic Kidney DiseaseObesityPedestrian InjuriesPhysical Health Not GoodStroke Health Risk Behaviors
Binge DrinkingCurrent Smoker
No Leisure Time for Physical Activity
Climate Change Exposures
Wildfire Risk
SLR Inundation Area
Children

11.1 69.43.7

18.5 40.2

15.5 40.0

10.7 0.066.442.388.562.3

10.6 34.90.043.5

7.6 89.1

70.9 54.125.00.040.5
25/27
Explorer Well v3 Detailed Report, 11/7/2023
Elderly
English SpeakingForeign-bornOutdoor WorkersClimate Change Adaptive CapacityImpervious Surface CoverTraffic DensityTraffic AccessOther IndicesHardship Other Decision Support2016 Voting

7.3. Overall Health & Equity Scores
Metric
CalEnviroScreen 4.0 Score for Project Location (a)
Healthy Places Index Score for Project Location (b)Project Located in a Designated Disadvantaged Community (Senate Bill 535)Project Located in a Low-lncome Community (Assembly Bill 1550)Project Located in a Community Air Protection Program Community (Assembly Bill 617)

39.00.00.091.484.20.023.00.0

0.0 Result for Project Census Tract

43.0 NoNoNo
a: The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.b: The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

7.4. Health & Equity Measures
No Health & Equity Measures selected.

7.5. Evaluation Scorecard
Health & Equity Evaluation Scorecard not completed.
26/27
Explorer Well v3 Detailed Report, 11/7/2023

7.6. hlealth & Equity Custom Measures
No Health & Equity Custom Measures created.

Data Provided by Applicant
Data Provided by applicantData Provided by Applicant
1 trip per day M-SData provided by applicant
27/27
Appendix B
Energy Calculations

APPENDIX B

ENERGY CALCULATIONS
Energy Use Summary
Construction Phase (gallons/construction perioc Gasoline DieselConstruction Vehicles 4,969 25,486 Worker Trips 7,659 19
Vendor Trips 28 0
Haul Trucks 0 352
Total 12,657 25,857
Offroad Construction Equipment Energy Use
Phase NameSite PieparaUorVMobilization
Site PreparaBorVMoblization
Site PwparatiorVMobiizatton
Noiss Ba me reNoise Barriers
WeIDriKngWel DrillingWel DrillingWelDriWel Drilling ContinuedWel Drilling ContiniiedWelDrilCng ContinuedWelOriBng Continued Wo I DevelopmentWe I Development
Wel DevetopmentWelDavekipmentInstal Test Pump. Wel Testing arEqiipment InstallationEquipment InstaUation Site DevetopmertBuikling ConstructionPaving
Architectural Coatings
Linear, Grading & Excavati
Linaar, Drahaga, Utiitiss, A Sub-(
Linear. Paving
Linear, Paving
.inear. Paving.inaar. Paving
Equipment TypaTractors/LoadersffiackhoesBore/Drl RigsCranesTractors/Loadefs/BackhoesBora/Dri RigsBore/Drl RiflsRough Terrain ForkBftsTractors/Loaders/BackhoesBore/Dri RigsPumpsGenerator Sets Tractors/Lo a de re/Backhoc s
Bore/Dril RigsPum|Generator SatspunnTractors/Loaders/BackhossBore/DrilRigsTractors/LoadersfBackhoesTractore/Loaders/BackhoasCement and Mortar MKBRPavereRolersTractors/Loaders/Bac khoesAir CompreasoR Trartore/Loaders/Baekhoes
Tractors/Loaders/BackhoesTractorc/LoadetsfiackhoesCement and KtortarMbors RollersPavers
FualTypeDto setDieselDreselDieselDie setDtesalDwselDieselDieselDieselDieselDieselDieselDieselDieselDieselDieselDieselDieselDieselDieselDiesslDieselDieselDieselDieselDieselDieselDieselDieselDiesel DieselDiesel
Engine TierAvarageAverage
AverageAverageAverageAverageAverageAverageAverageAverage AverageAverageAva rage
Average
Aueraga
AverageAverageAverage
Average
Number per Hours Per Dai Horsepower Load Factor
84 0.37
8 Fud
2424248
242424
24242424888867
7 76a
&3
36784
83B337119684
8484
10 81
368437
64 10
36 0.50.290.37osos0.480,40.370.50.740.740.37050.740.74

0.74 0.37

0.50.37 0.37

0.560.420.380.37

0.480.370.370.370.56

0.380.42
Hw;« power Cttegofy
1001003001001DO100
100
100100100100100100
100
100100100
100
100100100
25 100100100100100100100
25 100100
Taar [galflioi
202.1
16166666292929291818
18 13
131313
21 261
261261261261
261261
261261110110110110
110
110
202.12024202420212024
2024
20242024202420242024202420242024202-120242024
2024
20242024202420242024
2024202420242024
202420Z4202-1202-1
2024202-1
Cnntumplkin Rita
lour)

2.23.31.62.22.2 1.31^

0.9 1.6

2.2 1.6

2.2 1.3

5.2 1.31.6

2.21.61.60.4 1.71.71.61.31.6

0.4 1.7

1.7 FualType
DiesslDieselDieselDieselDieselDieselDiesel
Diesel
Diesel
Gasoline
DieselDinselDteset
Gasoline
D'fes^IDi&selDtesetDiesel
Gasoline
DieselDieselDiesolDieselDiesel
Diesel
Diesel
Gasoline
DieselDiesel
Total Fuel Contumplion(galfconifnidton period)
75 138121
623sea
749
442691
73 S09
1S4
336310
1,198167
2,4622,2462.4622.4G21.3521,327
1,176
2,154
995
1,0381,0381,038
760
567
Total Gasoline
Total Diesel
4,969
25,486
Onroad Construction Energy Use
DaiMrip*PhattName
rBparatBnAWifcalion
Drillng Continued S£
Etodricity Plua.in Hybrid
1S2.S79
Lwgfh
'^
;K
Grading &B(cavalian
Llnaaf. Drain^e. Utittiia. t SutkGr»iBLineaf. Pwing
DrilingDwalotmeM
Instal Tut Pump, Wd Tuting and Sarr^ing
SitBD-MtapmmtBuiUingi
. PiK>ari*ion*l<Afeation
WdlDrilingCortinUBlPxingGradini) & Bnaiatini
Dfainagt, Utittia, 4 SuWSraK
Linnr, PwnB
NoiuBfrinWal Driling
WdlO^Axxn.nt
[ntta* Tast Pun^i, Wal TtUnq and Swrvi
4B5217.597.5
157,5

65.25 65,25
ArchitBcturd CaitinBi
Appendix C
Geotechnical Report

APPENDIX C

GEOTECHNICAL REPORT

GEOTECHNICAL EXPLORATION

JET PROPULSION LABORATORY

MONK HILL TREATMENT SYSTEM OPTIMIZATION
XPLORER WELL & BEHNER WATER TREATMENT PLANT]

HAHAMONGNA WATERSHED PARK
JPL EAST PARKING LOT, 3200± EXPLORER ROAD

PASADENA, CALIFORNIA
CIVILTEC PROJECT NO. 2017170.00
Prepared For:

CIVILTEC ENGINEERING, INC
118 West Lime Avenue, Second Floor
Monrovia, California 91016-2841
Project No. 11877.001
January 16,2018
I
«y
Leighton Consulting, Inc.

A LEIGHTON GROUP COMPANY
Leighton Consulting, Inc.

A LEtGHTON GROUP COMPANY
Tuesday, January 16, 2018
Project No. 11877.001
Civiltec Engineering, Inc.
118 West Lime Avenue, Second Floor
Monrovia, California 91016-2841
Attention: Mr. Bed P. Dawadi, PE
Project Manager
Subject: Geotechnical Exploration
Jet Propulsion Laboratory Monk Hill Treatment System Optimization Explorer Well and Behner Water Treatment PlantHahamongna Watershed Park JPL East Parking Lot, 3200± Explorer Road
Pasadena, California
Civiltec Project No. 2017170.00
In accordance with our August 21, 2017 proposal authorized on December 8, 2017, Leighton Consulting, Inc. is pleased to present results of our geotechnical exploration to support design of the new Explorer Well and treatment vessels to be installed at the Behner Water Treatment Plant (WTP) southeast of the Jet Propulsion Laboratory (JPL) in Pasadena, California.

This site is not located within a currently designated Alquist-Priolo Earthquake FaultZone. However, strong seismic ground shaking has and will occur at this site. This sitej^ located within a potential liquefaction hazard zone. However, groundwater was not encountered in our December 22, 2017 test pits excavated to a maximum depth of 8 feet at the Explorer Well site. Historical high groundwater levels were mapped at 20feet below the ground surface at the Explorer Well site and at least (s) 50 feet deep at the Behner Water Treatment Plant. Potential for liquefaction occurring at the BehnerWTP site is extremely low due to the lack of shallow groundwater and high density ofold alluvium on this terrace located slightly above the Arroyo Seco wash. Potential for liquefaction occurring at the Explorer Well site is low due to the coarse and well graded alluvium with cobbles and boulders.
611 Wilshire Blvd., Suite 1404 » Los Angeles, CA 90017-2907 213.892.1530 -213.892.1563Fax. tAww.leightongroup.com
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 Based on our findings, conventional spread footings and/or mat foundations (integrated footings and slab-on-grade), bearing on undisturbed gravel alluvium and/or new properly compacted fill over undisturbed alluvium, may be used to support the proposed masonry well house at the new well.

We appreciate the opportunity to be of additional sen/ice to Civiltec Engineering, Inc. If you have any questions about this report, or if we can be of further service, please contact the undersigned at either (909) 484-2205 or (866) LEIGHTON, directly at the phone extension and/or e-mail address listed below.

Respectfully submitted,
LEIGHTON CONSULTING, INC.

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Smas'C.'Benson: Jr, 0^^091
President and CEO
Extension 8771, tbenson(a)leiahtonconsultina.com
Distribution: (1) addressee (via e-mail PDF)
2 €Leighton

TABLE OF CONTENTS
Section Page

1.0 INTRODUCTION ........................................................................................... 1 -

1.1 Site Location and Description.............................................................. 1 -

1.2 Proposed Wellhouse and Vessels....................................................... 1 -

1.3 Purpose and Scope of Evaluation......................................................-2 -

2.0 FINDINGS...................................................................................................... 3-3.0

2.1 Regional Geotechnical Setting............................................................3 -

2.2 Subsurface Soil Conditions.................................................................3 -

2.3 Groundwater......................................................................................-4-

2.4 Seismicity............................................................................................5 -

2.5 Secondary Seismic Hazards..............................................................-5 -

2.5.1 Liquefaction Potential:............................................................- 5 -2.5.2 Seismically Induced Settlement:............................................. 6 -2.5.3 Seismically Induced Landslides:............................................. 6 -2.5.4 Earthquake-lnduced Seiches and Tsunamis:.........................- 6 -

2.5.5 Earthquake-lnduced Inundation:............................................. 6 - CONCLUSIONS AND RECOMMENDATIONS3.13.2

3.33.4 ..-7-
Conclusions .......................................................................................-7 -Recommendations Summary.............................................................. 7 - Salvaging the Behner Plant Tank Mat Foundation.............................-7 -Earthwork............................................................................................8 -

3.4.1 Site Preparation:..................................................................... 8 -

3.4.2 Undocumented Fill Soil Overexcavation: ................................ 9 -3.4.3 Subgrade Preparation:............................................................ 9 -

3.4.4 Fill Placement and Compaction:.............................................- 9 -

3.4.5 Utility Trench Backfill:.............................................................-9-

3.4.6 Surface Drainage:................................................................. 10 -

3.5 Seismic Design Parameters.

3.6 Conventional Shallow Spread Footing and/or Mat Foundations

3.6.1 Minimum Embedment and Width:

3.6.2 Allowable Bearing Pressure:

3.6.3 Lateral Load Resistance:

3.6.4 3.7 Retaining Walls................................................................................. 12 -

3.7.1 Design Static Lateral (Horizontal) Earth Pressures:.............. 12 -3.7.2 Retaining Wall Surcharges:..................................................-13 -3.7.3 Retaining Wall Incremental Seismic Loads:.......................... 13 -

3.7.4 Sliding and Overturning:.......................................................-14 -3.7.5 Drainage: .............................................................................. 14 -

3.8 Concrete Slab-On-Grade.................................................................. 14 -

3.9 Sulfate Attack and Ferrous Corrosion Protection.............................. 15 -

3.9.1 Sulfate Exposure:.................................................................-15 -

3.9.2 Ferrous Corrosivity:............................................................... 16 -

3.9.3 Corrosivity Test Results:....................................................... 16 -

4.0 CONSTRUCTION CONSIDERATIONS....................................................... 17 - .^Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001

4.1 Temporary Excavations .................................................................... 17 -

4.2 Temporary Trench Shoring ............................................................... 18 -

4.3 Geotechnical Services During Construction...................................... 18 -

5.0 LIMITATIONS..............................................................................................19-REFERENCES List of Tables
Table 1. 2016 CBC Site Categorization/Coefficients.

Table 2. Retaining Wall Design Earth Pressures
Table 3. Sulfate Concentration and Exposure,Table 4. Soil Resistivity and Soil Corrosivity Table 5. Results of Corrosivity Testing.

Page
.-10-.-12-.-16-.-16-.-17-
List of Figures
Figure 1 - Site Location MapFigure 2 - Regional Geology Map Figure 3 - Seismic Hazard Map
List of Plates
Plate 1 - Geotechnical Map (in pocket)
List of Appendices
Appendix A - Field ExplorationAppendix B - Geotechnical Laboratory Testing Appendix C - Earthwork and Grading Guide Specifications ^
Leighton

1. TRODUCTIO

1.1 Site Location and Description
As depicted on Figure 1 , S/te Location Map, this site is located in northwestern Pasadena on the east bank of the Arroyo Seco southeast of the Jet PropulsionLaboratory (JPL); at the northern portion of the Hahamongna Watershed Park.

There are two components and sites for this project, depicted on Plate 1, Geotechnical Map (in pocket), described as follows:

Explorer Well (Test Pit 1): This proposed Explorer Well site is currently vacant within a relatively flat area located just west of Explorer Road, on the east bank of the Arroyo Seco infiltration basins. This site is down within the Arroyo Seco wash at elevation 1,108-feet. There were east-west trending power lines aligned over this site. This proposed well head will be located 40- feet south of these power lines.

Behner Water Treatment Plant (Test Pit 2): The existing Behner Water Treatment Plant (WTP) is currently inactive, located on a terrace at the east bank of the Arroyo Seco; northeast of the Explorer Well site. New vessels are to be installed on the south end of the plant on an existing reinforced concrete mat that supports existing vessels, which are to be removed. December 7,1971 "as-built" plans show the plan pad at elevation 1,163 feet (presumably NGVD29 datum).

1.2 Proposed Wellhouse and Vessels
This new well and modifications to the inactive Behner WTP are proposed asfollows:

Explorer Wellhouse: A masonry well house will be designed to house this new well pump and other necessary equipment for operation of the pump.Preliminary Civiltec plans show a rectangular footprint for this wellhouse as 36-feet aligned roughly north 36° east by 12-feet wide. We also assume that the well house finish floor elevation will be at or within 5 feet above existing grade. Masonry bearing wall loads are not expected to exceed 3-kips-perfoot.

Treatment Vessels at Behner Water Treatment Plant (WTP): New water treatment equipment is to be installed at the existing inactive Behner WTP.The current Behner chemical storage area will be modified to house new ionexchange and liquid-phase granular activated carbon (LGAC) treatment vessels. These vessels are expected to have an 8-foot-diameter footprint, 4Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 weighing 10-kips or less. One possibility will be to install both vessels atop anexisting mat foundation, which is currently supporting 8-foot-high, 12-footdiameter "caustic soda" and "alum" storage tanks. Grade changes are not expected to be required at this plant, and the intent is to salvage the existingreportedly 8-inch-thick elongated-octagonal mat supporting these existingtanks. December 7, 1971 "As Built" plans by James M. Montgomery show that this 8-inch-thick mat foundation is reinforced with No. 4 bars spaced 12- inches on center "both ways."

1.3 Purpose ancLScope of Evaluation
Our scope of work was performed in accordance with our August 21, 2017proposal authorized on December 8, 2017 by Civiltec Engineering, Inc. This geotechnical exploration has included the following tasks:

Research: We reviewed available in-house geotechnical reports, literature and maps relevant to this site to look for potential geotechnical issues thatmay impact these proposed improvements. Key documents reviewed are referenced at the end of this report.Subsurface Exploration (Two Test Pits): Prior to excavation, we marked proposed test pit locations for Underground Service Alert (USA), so they would mark known public underground utilities to avoid at our proposed test pit locations. Two shallow test pits were excavated with a rubber-tire backhoe to depths of approximately 5 and 8 feet. These test pits were logged by a member of our technical staff during excavation. Bulk soil samples were obtained from these test pits at selected depth intervals and transported to our in-house geotechnical laboratory for testing. Exposed conditions weredigitally photographed. All test pits were then backfilled with excavated soil.

A description of field procedures, test pit logs and photos are presented in Appendix A, Field Exploration. Test pit locations are shown on Plate 1, Geotechnical Map.

Geotechnical Laboratory Tests: Geotechnical laboratory tests were performed at our in-house laboratory on recovered bulk soil samples obtained from our field exploration. Undisturbed drive sampling was not possible due to cobbles and boulders at this site. This laboratory-testing program was designed to classify and measure physical/engineering characteristics ofsampled soils. Test procedures and results are presented in Appendix B, Geotechnical Laboratory Testing.Geotechnical Analyses: Data from our background review, test pits andgeotechnical laboratory testing was evaluated and analyzed to develop geotechnical conclusions and provide geotechnical recommendations for theproposed wellhouse and vessels. -2-
€
Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 Report Preparation: Results of this evaluation have been summarized in this report, presenting our findings, conclusions and geotechnical recommendations for the proposed improvements.

This report does not address the potential for hazardous materials in soil and/orgroundwater.

2.0 F DING

2.1 Regional Geotechnical Setting
This site is located within the Pasadena Quadrangle, and there are not any currently (early January 2018) designated Alquist-Priolo Fault Zones within thePasadena Quadrangle, as can be seen here:
httD://amw.conservation.ca.aov/SHP/EZRIM/MaDS/PASADENA EZRIM.pdf However, this site is near the southern margin of the San Gabriel Mountains, and the Sierra Madre Fault Zone trends east-west along the southern margin of the San Gabriel Mountains. Locally, the United States Geological Survey's (USGS's)Professional Paper 1339, Plate 2.6 (1987) depicts the Bridge Fault segment of the Sierra Madre Fault Zone as being located north of and at the Explorer Road Bridge over the Arroyo Seco; which is north of this site. Faulting would not be visible within the alluvium of the Arroyo Seco and fault studies were beyond the scope of this foundation exploration scope of work. However, we are unaware of anything that would suggest active faulting through this wellhouse, at this time.

Figure 2, Regional Geology Map, shows that the wellhouse is located within young alluvial wash (Qw) materials of the Arroyo Seco, while the Behner Plant is located within old alluvial valley (Qoa) deposits, which had been uplifted and incised by the Arroyo Seco. Dibblee (DF-23, 1989) is consistent with this regional mapping depicted on Figure 2 for this site.

2.2 Subsurface Soil Conditions
Fill soils were encountered at Test Pit TP-1 (wellhouse site) to a depth of 3 feetbelow existing ground surface. Fill soils were also encountered to depths of 2- feet within Test Pit TP-2 at the Behner Plant; but based on as-built plans for this plant, basin/vault (retaining wall) backfill could be as deep as 18 feet in thecentral portion of the plant, which was constructed in or around 1969 to 1971 (notlikely compacted to modified Proctor relative compaction densities). We are -3- €
Leighton
Civiltec, JPL Explorer WeN^nd BehnerWTP Improvements. 11877.001

2.3 unaware of any fill placement documentation for this site, so all encountered fillsoils are classified as undocumented fill (Afu).

Topsail was encountered at the surface of TP-2 (east edge of Behner Plant).

Below topsail and fill soils, young and old alluvial soils (Qw and Qoa), consisting of very well graded sand, gravel, cobbles and boulders, with up to 6-percent fines(silt, measured) were encountered in our test pit excavations to the maximumdepths explored of 5 feet and 8 feet. We encountered refusal at Test Pit TP-1 at a depth of 8 feet. At this refusal depth, large boulders up to 3-feet in diametercould not be removed with a backhoe. Based on observations during excavation, the subsurface granular soils appear to be medium dense to very dense.

Boulders and cobbles appeared to be well graded and nestled in a dense matrix,but ranged from angular to sub-rounded (see photos in Appendix A).Undisturbed drive sampling or nuclear gauge density testing was not possible within this cobble and boulder alluvium matrix. Clays were not encountered and expansive native soils were not encountered and are not expected in this area ofPasadena.More detailed descriptions of soil encountered are provided on test pit logs in Appendix A.

GroundwaterGroundwater was not encountered within our test pits excavated on December22, 2017 to a maximum depth of 8 feet. Historically high groundwater levelshave been mapped in the Arroyo Seco at approximately 20 feet deep (CGS, 1998), see:
http://c]mw.conservation.ca.gov/SHP/EZRiM/Re£orts/SHZR/SHZR 014 Pasadena.pdf Data collected from a nearby groundwater well was utilized to assess the potential for shallow groundwater at the Behner WTP (Depari:ment of Water Resources, 2017). Groundwater was recorded on October 13, 2017 at an elevation of 955.73 feet. Based on information from the groundwater well, groundwater at the Behner WTP is expected to be greater-than (>) 200 feet below ground surface. CGS maps historic high groundwater as greater-than (>)50 feet deep below the Behner WTP. -4-
4 Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvem ents 11877.001

2.4 Seismicitv
Most important seismic hazard that has and will impact this site is ground shaking resulting from an earthquake occurring along several major active or potentially active faults within southern California. Following ASCE 7-10procedures, the site-specific Peak Horizontal Ground Acceleration (PGA) is0.994g, and the PGAM is also 0.994g (FpcA=1 for Site Class D). As an addedcheck, the PGA and hazard deaggregation were also estimated using the UnitedStates Geological Survey's (USGS) 2008 Interactive Deaggregations utility.

Results of this analysis indicate that the predominant modal earthquake has aPeak Horizontal Ground Acceleration (PHGA) of 1.055g with a modal Magnitude of approximately 7.7 (Mw) at a distance on the order of 51/^ kilometers for the Maximum Considered Earthquake (MCE, 2% probability of exceedance in 50 years; 2,475-year recurrence interval). Corresponding PGA for the designearthquake (two-thirds of the MCE) from the deaggregation tool would be 0.70g.Note that 2016 CBC seismic coefficients for building design are presented later inthis report.

2.5 Secondary Seismic Hazards
In general, secondary seismic hazards for sites in this region could include soil liquefaction, earthquake-induced settlement, lateral displacement, landslidingand earthquake-induced flooding. The potential for secondary seismic hazards at this site is discussed below.

2.5.1 Liquefaction Potential: Liquefaction is the loss of soil shear strength due to a buildup of pore-water pressure during severe and sustained ground shaking. Liquefaction is associated primarily with loose (low density),saturated, fine-to-medium grained, cohesionless soils. As shaking action of an earthquake progresses, soil grains are rearranged and densify within a short period of time. Rapid densification of soil results in a buildup of porewater pressure within saturated soils. When the pore-water pressure approaches the total overburden pressure, then soil shear strength reduces greatly and this soil temporarily behaves similarly to a fluid. Effects of liquefaction can include sand boils, settlement and bearing capacity failures below structural foundations.

As depicted on Figure 3, Seismic Hazard Map, this site ]s located within a potential liquefaction hazard zone. However, groundwater was not encountered in our December 22, 2017 test pits excavated to a maximum depth of 8 feet at the Explorer Well site. Historical high groundwater levelswere mapped at 20 feet below the ground surface at the Explorer Well site and at least (s) 50 feet deep at the Behner Water Treatment Plant. Potential -5-
^
Leighton
dviltec, JPL Explorer Well and_BehnerWTP Improvements 11877.001 for liquefaction occurring at the Behner WTP site is extremely low due to the lack of shallow groundwater and high density (N>30) of old alluvium on this terrace located slightly above the Arroyo Seco wash. Potential for liquefaction occurring at the Explorer Well site is low due to the coarse andwell graded alluvium with cobbles and boulders.

Note that due to the cobbles and boulders, conventional hollow-stem auger drilling and Standard Penetration Test (SPT) sampling is futile; but this material would obviously have SPT blow counts (N-values) greater-than (>) 30; which is, by definition, not liquefiable.

2.5.2 Seismically Induced Settlement: During a strong seismic event, seismically induced settlement can occur within loose to moderately dense, dry orsaturated granular soil. Settlement caused by ground shaking is often nonuniformly distributed, which can result in differential settlement.

The potential total settlement resulting from seismic shaking associated with a peak ground acceleration of 0.70g is estimated to be negligible based on thegravelly nature of soils underlying this site with cobbles and boulders, whichwere deposited in a dense, high-energy environment.

2.5.3 Seismicallv Induced Landslides: Both sites are generally level without significant slopes. These sites are not considered susceptible to either staticor seismically-induced slope instability.

2.5.4 Earthquake-lnduced Seiches and Tsunamis: Seiches are large waves generated in enclosed bodies of water in response to ground shaking.

Tsunamis are predominately ocean waves generated by undersea large magnitude fault displacement or major ground movement.Based on separation of the site from any body of water, seiche impact at thissite is highly unlikely. Also, due to the inland location of this site and finish floor elevation at 1,108 feet above mean sea level, relative to the Pacific Ocean (see California Geological Survey, 2009) tsunami risks at this site is nil.

2.5.5 Earthquake-lnduced Inundation: Earthquake-induced flooding can be caused by failure of dams or other water-retaining structures as a result of earthquakes. This upper portion of the Arroyo Seco (upstream of Devil's Gate Dam) is not located within a dam failure inundation zone (although various upstream and uphill water tanks and relatively small enclosedresen/oirs could fail and flood the low-lying Arroyo Seco area on the order ofa foot deep). Therefore, the potential for earthquake-induced flooding to occur at this pad due to a failure of a dam is considered nil. -6-
«Leighton
Civiltec, JPL Explorer Well and Behn^r_WTP Improvements 1187LOQ1

3. CONCLUSIONS A co ATIONS

3.1 Conclusions
This site is not located within a currently designated Alquist-Priolo Earthquake Fault Zone. However, strong seismic ground shaking has and will occur at thissite. This site js located within a potential liquefaction hazard zone. However, groundwater was not encountered in our December 22, 2017 test pits excavatedto a maximum depth of 8 feet at the Explorer Well site. Historical high groundwater levels were mapped at 20 feet below the ground surface at the Explorer Well site and at least (s) 50 feet deep at the Behner Water TreatmentPlant. Potential for liquefaction occurring at the Behner WTP site is extremelylow due to the lack of shallow groundwater and high density of old alluvium on this terrace located slightly above the Arroyo Seco wash. Potential for liquefaction occurring at the Explorer Well site is low due to the coarse and well graded alluvium with cobbles and boulders.

3.2 Recommendations Summary
Based on our findings, conventional spread footings and/or mat foundations (integrated footings and slab-on-grade), bearing on new properly compacted fillover undisturbed alluvium, may be used to support the proposed well house.

However, existing undocumented fill should not be used for new structure support. Undocumented fill soils were encountered in our test pits to depths of 2to 3 feet below existing grades. Therefore, up to 3-feet of overexcavation andrecompaction of undocumented fill will be required below existing grade withinbuilding footprint areas, extending approximately 3-feet horizontally out beyondthe outside perimeter of proposed building footprints. Cobbles and boulders larger-than (>) 6-inches in largest dimension should not be used in newengineered/compacted fill. Cobbles and boulders can be placed upstream of the wellhouse as rip-rap protection for possible flooding of the low-lying Arroyo Seco.

It is conceptually recommended to raise the wellhouse finish floor elevation above existing grade in this area, to avoid probable flooding in this area.

Specific design recommendations are provided in the following subsections, followed by a discussion of construction considerations later in this report.

3.3 Salvaging the Behner Plant Tank Mat Foundation
The current Behner chemical storage area (south side of plant) will be modified to house new ion-exchange and liquid-phase granular activated carbon (LGAC) -7-
«Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 treatment vessels. These vessels are expected to have an 8-foot-diameterfootprint, weighing 10-kips or less. One possibility will be to install both vessels atop an existing mat foundation, which is currently supporting 8-foot-high, 12- foot-diameter "caustic soda" and "alum" storage tanks. Grade changes are not expected to be required at this plant, and the intent is to salvage the existing reportedly 8-inch-thick elongated-octagonal mat supporting these existing tanks.December 7, 1971 "As Built" plans by James M. Montgomery show that this 8- inch-thick mat foundation is reinforced with No. 4 bars spaced 12-inches on center "both ways."
Empirically, if the new tanks weigh less-than existing tanks to be removed, then this approach to salvage the octagonal mat foundation is reasonable. Also, if the new tank contact pressure is <200 pounds-per-square-foot (psf) dead load, then salvaging the existing octagonal mat foundation is reasonable. However, after demolition is completed and the existing tanks are removed, then this mat should be carefully observed at the surface for cracking and deterioration. Both theproject Structural Engineer (SE) and our Geotechnical Engineer (GE) should view this mat once completely exposed. If modest cracking and/or concretedeterioration is observed, then perhaps some concrete coring and testing may be required; and epoxy repairs and/or other repairs may be required. If excessive cracking is observed, then the mat may need to be replaced.

3.4 Earthwork
Primary earthwork is expected to consist solely of undocumented fill overexcavation down approximately 3-feet below existing grade, within the wellhouse footprint and 3-feet beyond the proposed wellhouse footprint, followed by backfill under and adjacent the wellhouse. Earthwork should be performed in accordance with Appendix C, Earthwork and Grading Guide Specifications.

Project-specific earthwork recommendations are provided in the followingsubsections.

3.4.1 Site Preparation: Prior to construction, areas of proposed improvements should be stripped of pavements, landscaping (trees, shrubs and irrigation systems), trash and debris. Any underground utilities or other obstructions onsite that interfere with proposed foundations should be removed/rerouted.

Efforts should be made to locate any existing buried utilities or substructures in areas of proposed improvements, before earthwork begins. Utilities shouldbe removed and rerouted where interfering with proposed construction, and resulting cavities should be backfilled and compacted as recommended in the following subsections.
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Civiltec, JPL Explorer Well and BehnerWTP Im p.rovem_ents 11877.001

3.4.2 Undocumented Fill Soil Overexcavation: Undocumented fill soils were encountered at the proposed wellhouse pad to depths of up to 3 feet below existing grade. Thus, it is anticipated that up to 3-feet of overexcavation and recompaction of undocumented fill will be required below the proposedwellhouse building, extending approximately 3-feet horizontally beyond the outside perimeter of the building footprint. At a minimum, 3-feet of soils below existing grade should be overexcavated and recompacted within thewellhouse footprint.

3.4.3 Subgrade Preparation: After undocumented fill soils have been excavated under proposed developments, exposed surfaces should be scarified to a depth of 6-inches, moisture-conditioned to or slightly above optimum moisture content, and compacted in accordance with the recommendations for fillpresented in Section 3.3.4, below. Finished compacted subgrade should befirm and non-yielding under weight of compaction equipment.

3.4.4 Fill Placement and Compaction: Onsite soils free of organics, debris and oversized material greater-than (>) 6 inches in largest dimension, are suitable for use as compacted structural fill; but should be carefully blended to a uniform gradation. Soil to be placed as fill, whether onsite or import material, should be reviewed by Leighton Consulting, Inc., and tested if and as necessary. Any imported soils must be non-expansive.

Relative compaction should be measured using the modified Proctor ASTM D1557 laboratory maximum density. Fill should be placed in thin, loose lifts, sufficiently and uniformly moisture-conditioned at or slightly above optimum moisture, and compacted to a minimum of 95 percent of the ASTM D 1557 laboratory maximum density where supporting the new wellhouse.

3.4.5 Utility Trench Backfill: Utility trenches should be backfilled in accordance with Section 306-12.2 (for narrow trenches) or Section 306-12.3 (for mechanically compacted backfill) of the Standard Specifications for Public Works Construction ("Greenbook"), 2015 Edition. Utility trenches can be backfilled with on-site soils free of debris, organic and oversized material up to (^) 3 inches in largest dimension. Prior to backfilling trenches, pipesshould be bedded in and covered with either:
(1) Sand: A uniform, granular material that has a Sand Equivalent (SE) of 30 or greater and a maximum particle size of 3A inches (or as specified by the pipe manufacturer), water densified in place, or (2) CLSM: Controlled Low Strength Material (CLSM) conforming to Section 201-6 of the Standard Specifications for Public Works Construction, ("Greenbook"), 2015 Edition.
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Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 Pipe bedding should extend at least 4 inches below any pipeline invert and at least 12 inches over the top of the pipeline. Native soils (free of large cobbles and boulders) can be used as backfill over the pipe-bedding zone, and shouldbe placed in thin lifts, moisture conditioned above optimum, and mechanically compacted to at least 90-percent relative compaction, relative to the ASTM D 1557 modified Proctor laboratory maximum density outside of the wellhouse footprint, or 95-percent within the wellhouse footprint.

3.4.6 Surface Drainage: Surface drainage should be designed to direct water away from the wellhouse and toward approved drainage devices. Surface drainage should be provided to prevent ponding of water adjacent tostructures or on pavements. In general, areas around buildings should slope away from buildings. Roof runoff should be carried to suitable drainageoutlets by watertight drainpipes or other paved areas.

Irrigation of landscaping adjacent to buildings (if any) should be controlled to maintain, as much as possible, consistent soil moisture content sufficient to provide healthy plant growth without over-watering and over-saturating the subgrade. Drought-resistant landscaping with drip-irrigation is suggested in areas adjacent to buildings, to reduce the potential for saturating slab-ongrade subgrades, which can result in moisture damage within buildings.

3.5 Seismic Design Parameters
Seismic parameters presented in Table 1, below, are intended for site-specific structural design of the wellhouse in accordance with the 2016 CBC:

Tab 1. 2016 CBC S Cat orization/Coefficients
2016 CBC Categorization/Coefficient
Site Longitude (decimal degrees)
Design Value
-118.16603
Site Latitude (decimal degrees) 34.20029
Site Class Definition (ASCE 7 Table 20.3-1)
D
Mapped Spectral Response Acceleration at 0.2s Period, Ss (Figure 1613.3.1(1)) 2.661g Mapped Spectral Response Acceleration at 1s Period, Si (Figure 1613.3.1(2)) 0.964g Short Period Site Coefficient at 0.2s Period, Fa (Table 1613.3.3(1)) 1.0 Long Period Site Coefficient at 1s Period, Fv (Table 1613.3.3(2) 1.5 Adjusted Spectral Response Acceleration at 0.2s Period, SMS (Eq. 16-37) 2.661g Adjusted Spectral Response Acceleration at 1s Period, SMI (Eq. 16-38) 1.446gDesign Spectral Response Acceleration at 0.2s Period, Sos (Eq. 16-39) 1.7749 Design Spectral Response Acceleration at 1s Period, SDI (Eq. 16-40) 0.964g Long Period (TL, seconds)
8 Seismic Design Category
E
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Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001

3.6 Conventional Shallow Spread Footing and/or Mat Foundations Conventional spread footings and/or mat foundations (integrated footings and slabs-on-grade) can be used to support the proposed wellhouse, if bearing on atleast 3 feet of new, properly compacted fill as described previously in this report.

Specific spread-footing or mat design recommendations are presented in thefollowing subsections.

3.6.1 Minimum Embedment and Width: Conventional shallow spread footings may be used, bearing solely on newly placed properly compacted fill as described previously in this report. Footings should be embedded at least 12- inches below lowest adjacent grade, with a minimum width of 12-inches forcontinuous bearing wall footings or 24-inches for isolated column footings. Ifflooding scour is expected, then spread footings should be embedded at least(s) 12-inches below the anticipated scour depth. Lowest adjacent finished grade may be taken as either (1) the lowest adjacent interior slab-on-grade surface, or (2) finished exterior grade below anticipated scour depth, whichever is lower. All footings located adjacent to utility trenches should be embedded below an imaginary 1:1 (horizontal:vertical) plane projected upward and outward from the bottom edge of the trench up to the footing.

This need not be the case for perpendicular aligned conduits, properly backfilled, penetrating under continuous footings.

3.6.2 Allowable Bearing Pressure: A net allowable bearing pressure of 3,000 pounds-per-square-foot (psf) may be used for static and sustained live loads, based on minimum embedment depth and widths described above. This allowable bearing value may be increased by 600 psf for each additional footof embedment below lowest adjacent grade, up to a maximum allowable bearing pressure of 6,000 psf. These allowable bearing pressures are for total dead loads and frequently applied live loads, and can be increased by one-third for short duration wind and seismic loads.

3.6.3 Lateral Load Resistance: Lateral (horizontal) loads on foundations may be resisted by both frictional resistance along the base of the footing and the passive resistance in properly compacted fill adjacent to the sides of footings.

Frictional resistance between the base of footings poured (cast) onundisturbed native sands may be computed using a coefficient of friction of0.5, or 50-percent of sustained dead loads. Passive resistance may be computed using an equivalent fluid pressure of 300 pounds-per-square-foot per foot of embedment below lowest adjacent grade (pcf), assuming there is constant contact between the footing and properly compacted fill soil.Passive pressure should not exceed 3,000 psf. These values may be increased by one-third when considering wind and seismic forces. Both friction and passive values have already been reduced by a factor-of-safety of

1.5, and can be used in combination.
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Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001

3.6.4 Settlement Estimates: Our recommended allowable bearing capacity is generally based on a total allowable, post construction settlement of approximately 1 inch. Differential settlement is estimated at approximately Vz inch over a horizontal distance of 30 feet. Since settlement is a function of footing size and contact bearing pressure, larger differential settlements can be expected between adjacent columns or walls where a large differentialloading condition exists. Conceptually, our settlement estimates are based on foundations bearing on 3-feet of properly compacted fill over dense/coarse alluvium. These settlement estimates should be reevaluated by Leighton Consulting, Inc. for unusual loading condition, and when foundation plans and loads for the proposed structures become available.

3.7 Retaining Walls
At the time of writing this report, need for new retaining wall was not identified and retaining walls may not be required. However, basement or vaults could be required, so recommendations presented in this section are based on a basement or vault height (retained earth height) no-greater-than (^) 12 feet.

Retaining wall geotechnical design parameters are presented in the following subsections:

3.7.1 Design Static Lateral (Horizontal) Earth Pressures: For drained retaining walls with level backfill, the following parameters may be used for retainingwall design:

Table 2. et all
Retaining Wall Condition
(Level Backfill)
Active (cantilever)
esign Earth Pres
Equivalent Fluid Pressure
(pounds-per-cubic-foot)*
30 r
At-Rest (braced) 45
Passive Resistance (compacted fill) 300**
*0nly for level and drained properly compacted backfill. **Allowable passive resistance should not exceed 3,000 psf in any event.

The project Structural Engineer should apply the applicable factors of safetyand/or load factors during design, as specified by the California Building Code.

Cantilever walls that are designed to yield at least 0.001 H, where H is equal to the wall height, may be designed using the active condition. Rigid wallsand walls braced at the top should be designed using the at-rest condition.Passive pressure is used to compute soil resistance to lateral structural movement. In addition, for sliding resistance, a frictional resistance coefficient of 0.5 may be used for concrete cast directly on soil. Lateral -12-
Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 passive resistance should be taken into account only where soil providing passive resistance, embedded against the foundation elements, will remain intact during the design life of the retaining wall.

3.7.2 Retaining Wall Surcharges: In addition to the above lateral forces due to retained earth, surcharge due to above grade loads on wall backfill, such asexisting building foundations, should be considered in design of retaining walls. Vertical surcharge loads behind a retaining wall on or in backfill within a 1:1 (horizontal:vertical) plane projection up and out from the retaining wall toe, should be considered as lateral and vertical surcharge. Unrestrained (cantilever) retaining walls should be designed to resist one-third of these surcharge loads applied as a uniform horizontal pressure on the wall. Braced walls should also be designed to resist an additional uniform horizontalpressure equivalent to one-half of uniform vertical surcharge-loads.

In areas where autos and pickup trucks will drive, we suggest assuming a uniform vertical surcharge of 300 psf, which would result in active and at-rest horizontal surcharges of 100 psf and 150 psf, respectively. This should be doubled in areas of heavy construction traffic (such as concrete trucks, heavy equipment delivery-trucks, etc.). If crane outrigger loads or other point loadsources are applied as wall surcharge, this will require additional analyses based on load magnitude and location relative to the wall.

3.7.3 Retaining Wall Incremental Seismic Loads: Seismic incremental loads need not be added to retaining walls with stem heights on the order of (^) 6- feet or less, with adjacent level backfill. However, for taller walls, incremental seismic earth pressures of 25 pounds-per-cubic-foot (pcf) can be applied for design, at the discretion of the Structural Engineer, in addition to static earth and surcharge pressures presented above. This is based on traditionalMononobe-Okabe (1929) equations. Traditionally, this incremental seismic earth pressure has been applied as an inverted triangle (inverted equivalent fluid pressure), with largest dynamic earth pressure occurring at the top of the wall (upper ground surface). Resultant seismic earth pressure force has traditionally been applied at approximately 0.61-1 from the bottom of the wall,where H is the wall (stem) height (e.g. Seed and Whitman, 1970).

However, recent studies (Sitar, et. al., 2010, U.C. Berkeley) suggest a uniformpressure distribution is likely closer to actual lateral seismic loads, so a uniform pressure of 12H (psf) applied as a uniform/rectangular pressure distribution can also be considered (based on current research and observations), at the discretion of the Structural Engineer. It is important toconsider that for level backfill and in areas without shallow groundwater, both case history reviews and centrifuge test results suggest all of theseapproaches above are conservative, particularly for retaining walls with modest heights such as we expect for this project. Seismic incremental loads -13-
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Cjvjltec, JPL Explorer Well and BehnerWTP Improvements, 11877.001 need only be added to active earth pressures, rather than at-rest earth pressures.

3.7.4 Sliding and Overturninfl: Total depth of retained earth for design of walls and for uplift resistance, should be measured as the vertical height of the stem below the ground surface at the wall face for stem design, or measuredat the heel of the footing for overturning and sliding. A soil total unit weight of120 pounds-per-cubic-foot (pcf) may be assumed for calculating surcharge weight of backfill over the wall footing, if drained, or 60 pcf if submerged, for properly compacted backfill.

3.7.5 Drainage: Adequate drainage may be provided by a subdrain system positioned behind the walls. Typically, this system consists of a 4-inch minimum diameter perforated pipe placed near the base of the wall (perforations placed downward). The pipe should be bedded and backfilled with pervious backfill material described in Section 300-3.5.2 of the Standard Specifications for Public Works Construction (Greenback), 2015 Edition. This pervious backfill should extend at least 2 feet out from the wall and to within 2 feet of the outside finished grade. This pervious backfill and pipe should bewrapped in filter fabric, such as Mirafi 140N or equivalent, placed as described in Section 300-8.1 of the Standard Specifications for Public Works Construction (Green Book), 2015 Edition. The subdrain outlet should be connected to a free-draining outlet or sump.

Miradrain, Geotech Drainage Panels, or Enkadrain drainage geocomposites, or similar, may be used for wall drainage as an alternative to the Class 2 Permeable Material or drain rock backfill, particularly where horizontal space is limited adjacent to shoring (where walls are cast against shoring). These drainage panels should be connected to the perforated drainpipe at the base of the wall.

3.8 Concrete Slab-On-Grade
Concrete slabs-on-grade should be designed by the project Structural Engineerin accordance with the 2016 CBC for a soil with a very low expansion potential.

The following are minimum slab recommendations. Requirements that are more stringent may be required by local agencies, the Structural Engineer, Architect and/or CBC. Slabs-on-grade should have the following minimum recommendedcomponents:

Subgrade: Slab-on-grade subgrade soil should be moisture conditioned to slightly above optimum moisture content to a minimum depth of 18 inches within improvement footprints, prior to placing steel and/or concrete. -14-
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Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements _11877,001 Moisture Barrier: A moisture barrier consisting of at least 15-mil-thick St6gO-Wrap VapOr barriers (See: httD://www.steaoindustries.com/Droducts/steao wrap vapor barrier.php ), or equivalent, should then be placed below slabs where moisture-sensitive floor coverings or equipment will be placed. More stringent moisture vapor barriers may be required for specialized floor coverings (e.g. parquetry wood veneer), as specified by the project Architect.Reinforced Concrete: A conventionally reinforced concrete slab-on-grade with a thickness of at least 5-inches should be placed in areas without heavy loads. Reinforcing steel should be designed by the structural engineer, but as a minimum should be No. 3 rebar placed at 24-inches on center, each direction, mid-depth in the slab. A modulus of subgrade reaction (k) as a linear spring constant, of 250 pounds-per-square-inch per inch deflection (pci) can be used for design of heavily loaded slabs-on-grade, assuming a linear responseup to deflections on the order of %-inch.

Minor cracking of concrete after curing due to expansion, drying and shrinkage isnormal, and should be expected. However, cracking is often aggravated by ahigh water-to-cement ratio, high concrete temperature at the time of placement,small nominal aggregate size, and rapid moisture loss due to hot, dry, and/or windy weather conditions during placement and curing. Cracking due to temperature and moisture fluctuations can also be expected. The use of lowslump concrete or low water/cement ratios can reduce the potential for shrinkagecracking.

3.9 Sulfate Attack and Ferrous Corrosion Protection

3.9.1 Sulfate Exposure: Sulfate ions in the soil can lower the soil resistivity and can be highly aggressive to Portland cement concrete by combining chemically with certain constituents of the concrete, principally tricalciumaluminate. This reaction is accompanied by expansion and eventual disruption of the concrete matrix. A potentially high sulfate content could also cause corrosion of reinforcing steel in concrete. Section 1904A of the 2016California Building Code (CBC) defers to the American Concrete Institute's (ACI's) ACI 318-14 for concrete durability requirements. Table 19.3.1.1 of ACI 318-14 lists "Exposure categories and classes," including sulfate exposure as follows:
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Civiltec, JPL Explorer Well and Behner WTP Improvements 11877.001 Table 3. Sulfate Concentratio
Soluble Sulfate in Water | Water-Soluble Sulfate (804)
(parts-per-million) [ in soil (percentage by weight)
d x p o
r
0-150 0.00-0.10
ACI 318-143ulfate Class
SO (negligible)
150-1,500 0.10-0.20 S1 (moderate*)
1,500-10,000 0.20 - 2.00 S2 (severe)
>10,000 >2.00 S3 (very severe)
*or seawater

3.9.2 Ferrous Corrosivitv: Many factors can modify corrosion potential of soil including soil moisture content, resistivity, permeability and pH, as well as chloride and sulfate concentration. In general, soil resistivity, which is a measure of how easily electrical current flows through soils, is the most influential factor. Based on the findings of studies presented in ASTM STP1013 titled "Effects of Soil Characteristics on Corrosion" (February 1989), theapproximate relationship between soil resistivity and soil corrosiveness wasdeveloped as follows:

Table 4. So esistivity and Soil Corrosivity

3.9.3 Soil Resistivity
(ohm-cm)
0 to 900
Classification of
Soil Corrosiveness
Very Severely Corrosive
900 to 2,300 Severely Corrosive
2,300 to 5,000 Moderately Corrosive
5,000 to 10,000 Mildly Corrosive
10,000 to >100,000 Very Mildly Corrosive
Acidity is an important factor of soil corrosivity. The lower the pH (the moreacidic the environment), the higher the soil corrosivity will be with respect to buried metallic structures and utilities. As soil pH increases above 7 (theneutral value), the soil is increasingly more alkaline and less corrosive to buried steel structures, due to protective surface films, which form on steel inhigh pH environments. A pH between 5 and 8.5 is generally considered relatively passive from a corrosion standpoint. Chloride and sulfate ion concentrations, and pH appear to play secondary roles in modifying corrosion potential. High chloride levels tend to reduce soil resistivity and break downotherwise protective surface deposits, which can result in corrosion of buriedsteel or reinforced concrete structures.Corrosivitv Test Results: To evaluate corrosion potential of soils sampled from this site, we tested a bulk soil sample for soluble sulfate content, soluble chloride content, pH and resistivity. Results of these tests are summarized below:
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Civiltec, JPL Explorer Well and BehnerWTP_lmprovements_ 11877.001 Tab 5.

Boring
Number
TP-2
es
Sample
Depth
(feet)
1/2 to 2
ts of Corrosivity Test
Sulfate
(mg/kg)
59 Chloride
(mg/kg)
124 1 5.6
Minimum
Resistivity
(ohm-cm)
28,000
Note: mg/kg = milligrams per kilogram, or parts-per-million (ppm) These results are discussed as follows:

Sulfate Exposure: Based on Table 19.3.1.1 of ACI 318-14, sulfate exposure should be considered Exposure Class SO for near-surface soils(upper 2 feet below existing grade) sampled at this site. Based on Table19.3.2.1 of ACI 318-14, for this Exposure Category SO, requires nocement type restrictions, and an /c' (28-day compressive strength) of at least 2,500 pounds-per-square-inch (psi) is required at a minimum forstructural concrete.

Ferrous Corrosivity: As shown above, minimum soil resistivity of 28,000 ohm-centimeters was measured in our laboratory test. In our opinion,based on resistivity correlation presented in Table 4, it appears for site soils that corrosion potential to buried steel may be characterized as "very mildly corrosive" at the site. No special soils-induced-corrosionmitigations are required. However, ferrous pipe can be protected by polyethylene bags, tap or coatings, di-electric fittings or other means to separate the pipe from on-site earth materials.

4.0 CONSTRUCTION CONS RATIONS

4.1 Temporary Excavations
Based on our field observations, caving of cohesionless alluvial soils will likely be encountered in unshared excavations. To protect workers entering excavations,excavations should be performed in accordance with OSHA and Cal-OSHA requirements, and the current (2015) edition of the California Construction Safety Orders:
(httD://www.dir.ca.ciov/title8/sb4a6.html)
Contractors should be advised that fill and cohesionless alluvial soils should be considered Type C soils as defined in the California Construction Safety Orders.

As indicated in Table B-1 of Article 6, Section 1541.1, Appendix B, of the California Construction Safety Orders, excavations less-than (<) 20 feet deep within Type C soils should be sloped back no steeper than 11/2:1 (horizontat:vertical), where workers are to enter the excavation. This may be -17- €
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Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 impractical near adjacent existing utilities and structures; so shoring may berequired depending on trench locations.During construction, soil conditions should be regularly evaluated to verify that conditions are as anticipated. The contractor is responsible for providing the"competent person" required by OShlA standards to evaluate soil conditions.

Close coordination between the competent person and Leighton Consulting, Inc. should be maintained to facilitate construction while providing safe excavations.

4.2 Temporary Trench Shoring
Typical cantilever shoring can be designed based on the active equivalent fluid pressure presented in the retaining wall section (e.g. 30 pcf). If excavations arebraced at the top and at specific depth intervals, then braced earth pressure may be approximated by a uniform rectangular soil pressure distribution. This uniformpressure expressed in pounds-per-square-foot (psf), may be assumed to be 15 multiplied by H for design, where H is equal to the depth of the excavation being shored, in feet. These recommendations are valid only for trenches notexceeding 12 feet in depth at this site.

4.3 Geotechnical Services During Construction
Our geotechnical recommendations presented in this report are based onsubsurface conditions as interpreted (interpolated and extrapolated) from twoexploratory test pits. Our geotechnical recommendations provided in this reportare based on information available at the time the report was prepared and maychange as plans are developed. Additional geotechnical exploration, testing and/or analysis may be required based on final plans. Leighton Consulting, Inc. should review site grading, foundation and shoring (if any) plans when available,to comment further on geotechnical aspects of this project and check to see general conformance of final project plans to recommendations presented in this report.Geotechnical observation and testing should be conducted during excavation and all phases of earthwork. Our conclusions and recommendations should be reviewed and verified by us during construction and revised accordingly if geotechnical conditions encountered vary from our initial findings andinterpretations. Geotechnical observation and testing should be provided:

During overexcavation,
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Leighton
Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 During compaction of all fill materials,During utility trench backfilling and compaction, and/orWhen any unusual geotechnical conditions are encountered.

5.0 LIMITATIONS
This report was based in part on data obtained from a limited number of observations, site visits, soil excavations, samples and tests. Such informationis, by necessity, incomplete. The nature of many sites is such that differing soilor geologic conditions can be present within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur overtime. Therefore, our findings, conclusions and recommendations presented inthis report are based on the assumption that Leighton Consulting, Inc. will provide geotechnical observation and testing during construction.

This report was prepared for the sole use of Civiltec Engineering, Inc. for application to the design of the proposed improvements in accordance withgenerally accepted geotechnical engineering practices at this time in southern California.
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Civiltec, JPL Explorer Well and BehnerWTP Improvements 11877.001 F CES
American Concrete Institute (ACI), 2014, Building Code Requirements for Structural Concrete (ACI 318-14), an ACI Standard, 2014, with March 12, 2015 errata.

American Society of Civil Engineers (ASCE), ASCE Standard/SEI 7-10, an ASCE Standard, 2010.

Bryant, W.A., and Hart, E.W., 2007, Fault-Rupture Hazard Zones in California, AlquistPriolo Earthquake Fault Zoning Act with Index to Earthquake Zones Maps, Department of Conservation, California Geological Survey, Special Publication

42. 2007 Interim Revision.

California Building Standards Commission, 2016, 2016 California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2, Based on 2015 International Building Code, Effective January 1,2017.

California Department of Water Resources (CDWR) of California, 2017, Water Data Library, http://www.water.ca.aov/waterdatalibrary/
Martin, G.R., and Lew, M., ed., 1999, "Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Liquefaction Hazards in California," Southern California Earthquake Center, dated March 1999.

Public Works Standards, Inc., 2015, Standard Specifications for Public Works Construction, 2015 Edition, published by BNI Building News.

United States Geological Survey (USGS), 2014, 2014 Interactive Deaggregations, Based on the 2014 update source and attenuation models of the NSHMP (Peterson and others, 2008), USGS website,
https://earthquake.usqs.qov/hazards/interactive/
United States Geological Survey (USGS), 2017, Seismic Design Maps, accessed December 26, 2017, downloaded fromhttp://earthquake.usqs.qov/desiqnmaps/us/application.php? Youd, T.L., Idriss, I.M., Andrus, R.D., Arango, 1., Castro, G., Christian, J.T., Dobry, R., Finn, L., Harder, L.F., Hynes, M.E., Ishihara, K., Koester, J.P., Liao, S.C., Marcuson, W.F. Ill, Martin, G.R., Mitchell, J.K., Moriwaki, Y., Power, M.S, Robertson, P.K., Seed, R.B., Stokoe, K.H. II, 2001, "Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils", Journal ofGeotechnical and Geoenvironmental Engineering, Vol. 127, No. 10, October 2001.
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SITE LOCATION MAP
JPL Explorer Well and Behner WTP Improvements
Hahamongna Watershed Park
J PL East Parking Lot, 3200 ± Explorer Road
Pasadena, California
Figure 1
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REGIONAL GEOLOGY MAP
JPL Explorer Well and BehnerWTP Improvements
Hahamongna Watershed Park
J PL East Parking Lot, 3200 ± Explorer Road
Pasadena, California
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SEISMIC HAZARD MAP
JPL Explorer Well and BehnerWTP Improvements
Hahamongna Watershed Park
JPL East Parking Lot, 3200 ± Explorer Road
Pasadena, California
Figure 3
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GEOTECHNICALM
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L ;XPLORATIO
Prior to excavation, we marked proposed test pit locations for use by Underground Service Alert (USA) and the City of Pasadena to identify buried utilities at these locations. On December 22, 2017, our field exploration consisted of excavating twoshallow test pits with a rubber-tire backhoe to depths of 5 and 8 feet below existingground surface. Test pit locations are depicted on Plate 1, Geotechnical Map (in pocket). Test pit logs and photos are also included in this appendix.During excavation, encountered earth materials were logged and sampled by a member of our technical staff, and soil samples reviewed later in our geotechnical laboratory.

Soils were described in accordance with the Unified Soil Classification System (ASTM D 2488). Representative bulk soil samples were obtained. These soil samples weretransported to our in-house geotechnical laboratory for further evaluation andgeotechnical testing. After logging and sampling, these test pits were backfilled with excavated soil.

Our attached subsurface exploration logs and related information depict subsurface conditions only at locations indicated and at the particular date designated on the logs.Subsurface conditions at other locations may differ from conditions occurring at these locations. The passage of time may result in altered subsurface conditions due to environmental changes; particularly changes in groundwater. In addition, anystratification lines on these logs represent an approximate boundary between soil typesand these transitions may be gradual.

A-1
«Leighton
GEOTECHNICAL TEST PIT LOG TP-1
Project No.

ProjectExcavation Comp.

Excavation MethodLocation
11877.001 12-22-17
Explorer Well and Behner Plant Improvements
Garrett Concrete Corinfl and Sawing, Inc.

Backhoe Excavation
Explorer Well Site, Altadena, CA
RSM
Date Excavated
Logged By
Pit WidthGround Elevation 1110'Sampled By RSM
3'xir
IpLU J=.
s 1°.

F0
-sl
s
I
6 z
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a.

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SOIL DESCRIPTION
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of theactual conditions encountered. Transitions between soil types may be gradual.
-S2
0 ^•s&
1110-1 0- SP @ Surface -ARTIFICIAL FILL (Afu) SAND with gravel (SP), loose, dry, light tan, fine to course-grained sand, some fine subangular gravel, A <,A
A
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1105
^
^
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B-1
3 sw @ 1' - Well-graded SAND (SW) with gravel and cobbles, medium dense, moist, brown to dark brown, fine to coarse-grained sand, fine to coarse subangular gravel, subrounded cobbles up to 12 inches, some boulders up to f5 inches wide, non-plastic fines. -200, AL
B-2
3 GW @ 3' - ALLUVIUM (Qal) GRAVEL (GW) with Sand, cobbles, and boulders, dense, moist, light brown/tan, fine to coarse-grained sand, fine to coarse subangular gravel, subrounded to subangular cobbles up to 12 inches, rounded boulders up to 3 feet wide.

SA.MD
1100 10
1 'ES:

TOTAL EXCAVATED DEPTH = 8 FEETTOTAL SAMPLED DEPTH = 8 FEET

NO GROUNDWATER ENCOUNTERED
BACKFILLED AND TAMPED ON 12/22/2017ELEVATIONS NOT SURVEYED.

BULK SAMPLE

C CORE SAMPLEG GRAB SAMPLER RING SAMPLES SPLIT SPOON SAMPLET TUBE SAMPLE TYPE OF TESTS:
.200 % FINES PASSING

AL ATTERBERG LIMITS

CN CONSOLIDATIONCO COLLAPSECR CORROSIONCU UNDRAINED TRIAXIAL DS DIRECT SHEAREl EXPANSION INDEXH HYDROMETERMD MAXIIV1UM DENSITCPP POCKET PENETROMETERRV RVALUE

SA SIEVE ANALYSISSE SAND EQUIVALENTSG SPECIFIC GRAVITYUC UNCONFINED COMPRESSIVE STRENGTH ^
* * *This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 1 of 1 a^f^-!?>:••-<!
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Project: 11877.001Scale: NTS
Eng/Geol; TCB
Date: January 2018
TEST PIT 1 PHOTOS
JPL Explorer Well and BehnerWTP Improvements
Hahamongna Watershed Park
JPL East Parking Lot. 3200 ± Explorer Road
Pasadena, California
Figure A-1
«
leisini
GEOTECHNICAL TEST PIT LOG TP-2
Project No.

Project
Excavation Comp.Excavation MethodLocation
11877.001 12-12-17
Explorer Well and Behner Plant Improvements
Garrett Concrete Corinfl and Sawing, Inc.

Backhoe Excavation
Behner WTP, Altadena, CA
RSM
Date Excavated
Logged By
Pit Width 5' x 5'
Ground Elevation 1165'Sampled By RSM
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SOIL DESCRIPTION
TOs So// Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locationsand may change with time. The description is a simplification of theactual conditions encountered. Transitions between soil types may begradual. ^
<" 1°
's
^
>>
1165-1
0 SM | @ Surface - TOPSOIL shrubs, leaves, roots, organics. t'fc'^'
1160-1 5-
B-1
2 SM @ 0.5' - ARTIFICIAL FILL (Afu) SILTi/ SAND (SM), loose, moist, brown, fine-grained sand, subangular gravel up to 3 inches, some subangular to subrounded cobbles.

B-2
2 GW @ 2' - ALLUVIUM (Qall GRAVEL (GW) with Sand, medium dense, moist, brown, fine- to coarse-grained sand,an<
to coarse gravel, subangular to subrounded cobbes up to 12 inches, wide.

CR
SA,MD
1155 10—|
1 VES:

TOTAL EXCAVATED DEPTH = 5 FEETTOTAL SAMPLED DEPTH = 5 FEET NO GROUNDWATER ENCOUNTEREDBACKFILLED AND TAMPED ON 12/22/2017ELEVATIONS NOT SURVEYED.

B BULK SAMPLEC CORE SAMPLEG GRAB SAMPLER RING SAMPLES SPLIT SPOON SAMPLE

JLTUBE SAMPLE
PfPE OF TESTS:
-200 % FINES PASSING

AL ATTERBERG LIMITS
CN CONSOLIDATIONCO COLLAPSECR CORROSIONCU UNDRAINED TR1AXIAL

DS DIRECT SHEAR

EXPANSION INDEX

H HYDROMETERMD MAXIMUM DENSITYPP POCKET PENETROMETERRV RVALUE

SA SIEVE ANALYSISSE SAND EQUIVALENT

SG SPECIFIC GRAVITYUC UNCONFINED COMPRESSIVE STRENGTH
€
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 1 of 1 ^l:.?'-^; A *-^. 's %s,^ K
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.'-•-^ , ^•.^.^•? (f. 6- • •- ,•.. ^ .>"• yr^fi 1t3& a. ^ »• ^,- Project: 11877.001
Scale; NTS
:ng/Geol: TC8
Date: January2018
TEST PIT 2 PHOTOS
JPL Explorer Well and Behner WTP Improvements
Hahamongna Watershed Park
JPL East Parking Lot, 3200 ± Explorer Road
Pasadena, California
Figure A-2
«
Lpii;hl;
APP x

GEOTEC CAL LABORATORY TEST G
Our geotechnical laboratory-testing program was directed toward a quantitative andqualitative evaluation of physical and mechanical properties of sampled soils at this site,and to aid in verifying Unified Soil Classification System (USCS) soil classification.

Moisture Content: Moisture content determinations were performed in general accordance with ASTM D2216 Test Methods, on samples obtained from our test pits.

Results of these tests are presented on test pit logs in Appendix A.

Grain Size (Sieve) Analyses: Bulk soil samples were subjected to mechanical grainsize analysis by sieving from U.S. Standard brass screens (sieves; ASTM Test Methods D6913 and D1140). Results were evaluated to establish tested soil Unified SoilClassification System (USCS) classifications. Grain-size distribution curves arepresented in this appendix on the "Particle-Size Distribution" sheets, and percent fines(percent passing the No. 200 U.S. Standard Sieve) are listed on test pit logs in Appendix A.

Atterberg Limits: Liquid Limit (LL), Plastic Limit (PL) and Plasticity Index (Pl) were determined for a soil sample suspected to contain clay, in accordance with ASTM D4318. Specimens were air-dried, passed through a No. 40 sieve and then wetted to different moisture contents. These liquid and plastic limit tests were performed on the soil fraction passing the No. 40 sieve. Results of these tests are presented on the"Atterberg Limits" sheets in this appendix.Modified Proctor Compaction Curve: A laboratory compaction curve (ASTM D1557) was completed for bulk soil samples to determine the modified Proctor laboratory maximum dry density and optimum moisture content. Results of this test are presented on the "Modified Proctor Compaction Test plot in this appendix.

Soil Corrosivity: A representative sample of soil was tested for corrosivity. Test for water-soluble sulfate, water-soluble chloride, pH and minimum resistivity were performed in accordance with State of California Standard Methods CTM 417 Part II, CTM 422, and CTM 532/643, respectively. These test results are presented at the end of this appendix.

B-1
Leighton
BOULDERS! COBBLES GRAVEL

COARSE FINE
SAND

COARSE MEDIUM FINE
FINES
SILT
U.S. STANDARD SIEVE OPENING

6.0" 3.0" 1 1/2" 3/4" 3/8" #4
U.S. STANDARD SIEVE NUMBER
#8 #16 #30 #50 #100 #200
100
1000.000 100.000 10.000 1.000
PARTICLE - SIZE (mm)

0.100
Project Name:Project No.:

Civiltec/PWP Explorer Well and Behner Plant
Improvements11877.001
I CLAY

HYDROMETER
90 - ^80 -70 -60 - -H^ £
"Uj
^
S 50-s \s 40 -£
30 - s
£a.
20 -
10 0

0.010 0.001
Leighton

PARTICLE - SIZE

DISTRIBUTION
ASTM D 6913
Boring No,: TP-1 Sample No.: B-2
Depth (ft.): 3^1 Soil Type: fSPIaSoil Identification: Yellowish brown poorlv-araded sand with gravel CSPIaGR;SA:FI : (»/o) 43 : 54: 3 jan-iy SA TP-1, B-2 @ 3-8

BOULDERSI COBBLES
100
IiI
90 }80 -I70 •)60 }5040 -I30 }20
10 I
0 1000.000
GRAVEL
COARSE
SAND

FINE I COARSE I MEDIUM FINE
FINES
SILT 1CLAY
U.S. STANDARD SIEVE OPENING U.S. STANDARD SIEVE NUMBER

6.0" 3.0" 11/2" 3/4" 3/8" #4 #8 #16 #30 #50 #100 #200

HYDROMETER
•+
N
±. 1--
-LJ
I
!
:• l-1
1-1—-I
N
t[
Tt^—1
100.000 10.000
Project Name: Civiltec/PWP Explorer Well and Behner Plant ImprovementsProject No.: 11877.001 «Leighton

PARTICLE - SIZE

DISTRIBUTION
ASTM D 6913

1.000
PARTICLE - SIZE (mm)
Boring No.: TP-2Depth (ft.): 2^

0.100 0.010
Sample No.: B-2
Soil Type : (SP-SM)

0.001
Soil Identification: park brown poorlv-araded sand with silt and gravel (SP-SM)a GR:SA:FI : (%) 42 : 53 : 5 jan-iy
SA TP-2, 8-2 @ 2-5
t
Boring No.

Sample No.Depth (ft.)Sample TypeSoil Identification
TP-1
B-l
1-3
Bulk
Olive brown
poorly-graded
sand with silt
and gravel (SP-1
SM)g
No Moisture Correction; ASTM D 1140 modified to include splitting the sample on the #4 sieve Total Sample Dry Weight DeterminationDry Weight of Soil + Container (g) 4229.5Weight of Container (9) 225.7Dry Weight of Soil (g) 4003.8Sample Dry Weight Determination, Retained on Sieve #4Dry Weight of Sample+Cont. (g) 1952.2Weight of Container (g) 108.4Weight of Dry Sample (g) 1843.8Sample Dry Weight Determination, Passing Sieve #4iDry Weight of Sample + Cont. (g) 669.7Weight of Container (g) 206.3'Weight of Dry Sample (g) 463.4After Wash'Method (A or B) B;Dry Weight of Sample + Cont. (g) 620.3Weight of Container _(SL 206.3Weight of Dry Sample (g) 414.0 % Passing No. 4 Sieve 53.9% Retained No. 4 Sieve 46.1°/o Passing No. 200 Sieve 5.8 €Leighton PERCENT PASSING No. 200 SIEVE ASTM D 1140 Civiltec/PWP Explorer Well and Behner Plant IProjectName: Improvements I Project No.: 11877.001 |Tested By: 0. Figueroa Date: 01/04/18 -200 TP-1, B-1 @ 1-3
€Leighton ATTERBERG LIMITS ASTM D 4318
Civiltec/PWP Explorer Well and Behner
Plant Improvements
11877.001
Tested By: S. Felter
Input By: J. Ward
Project Name:Project No. :Boring No.:

Sample No.:

Soil Identification: Olive brown poorly-graded sand with silt and gravel (SP-SM)g TP-1
B-l
Checked By: J. Ward
Depth (ft.) 1-3
Date: 01/08/18Date: 01/09/18

TEST PLASTIC LIMIT LIQUID LIMFT
NO. 1 2 1 2 3 4
Number of Blows [N]
Wet Wt. of Soil + Cont. (g)
Dry Wt. of Soil + Cont. (g)Wt. of Container (g)Moisture Content (%) [Wn] Cannot be rolled:

NonPlastic
5 95.40 | Cannot get more than 5 blows:88.30 iNonPlastic

59.20 24.40
Liquid Limit NPPlastic Limit NPPlasticity Index NP
Classification NP
PI at "A"-Line = 0.73(LL-20)One - Point Liquid Limit Calculation LL =Wn(N/25)

PROCEDURES USED
Wet Preparation
Multipoint -Wet
X I Dry Preparation
Multipoint - Dry
x Procedure A
Multipoint TestProcedure BOne-point Test
;s
^
I
0 2I
2625 -I
24 -I
23 10
fcIj^
60 For classification offinegrained soils and finegrained fraction of coarsegrained soils 50 - CH or OH 40 -
"A" Line
30 -
CL or OL
20 -
10 -
MH or OH
/ CL-ML / ML or OL
0 0 10 20 30 40 50 60 70 80 90 100
Liquid Limit (LL)
20 25 30 40
Number of Blows
50 60 70 80 90 100
« MODIFIED PROCTOR COMPACTION TEST Leighton ASTM D 1557 Civiltec/PWP Explorer Well and Behner
Plant Improvements Tested By: 0. Figueroa
11877.001 Input By: J. Ward
TP-1
B-2
Date: 01/04/18Date: 01/09/18
Depth (ft.): 3-8
Project Name:Project No.:Boring No.:

Sample No.:Soil Identification: Yellowish brown poorly-graded sand with gravel (SP)g Note: Corrected dry density calculation assumes specific gravity of 2.70 and moisture content of 1.0% for oversize material
Preparation
Method:

Compaction
Method
xx
Moist
DryMechanical RamManual Ram
Scalp Fraction (%)
#3/4 23.9#3/8
#4
Rammer Weight (Ib.)
Height of Drop (in.)
Mold Volume (ft3)

10.0 18.0

0.07450
TEST NO. 1 2 3 4 5 6
Wt. Compacted Soil + Mold (g) 7178 7318 7447 7425
Weight of Mold (g) 2672 2672 2672 2672
Net Weight of Soil (g) 4506 4646 4775 4753
Wet Weight of Soil + Cont. (g) 767.3 857.0 958.5 970.0
Dry Weight of Soil + Cont. (g) 733.7 802.0 880.9 874.5Weight of Container (g) 72.5 74.3 82.8 77.8 Moisture Content (%) 5.08 7.56 9.72 11.99Wet Density (pcQ 133.3 137.5 141.3 140.6 Dry Density (PCf) 126.9 127.8 128.8 125.6
Maximum Dry Density (pcf)
Corrected Dry Density (pcf)
II Procedure A
Soil Passing No. 4 (4.75 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers: 5 (Five)Blows per layer: 25 (twenty-five)
May be used if +#4 is 20% or less
II Procedure B
Soil Passing 3/8 in. (9.5 mm) SieveMold : 4 in. (101.6 mm) diameterLayers: 5 (Five) Blows per layer: 25 (twenty-five)
Use if +#4 is >20% and +3/8 in. is
20% or less
fX] Procedure C
Soil Passing 3/4 in. (19.0 mm) Sieve
Mold : 6 in. (152.4 mm) diameterLayers: 5 (Five)Blows per layer: 56 (fifty-six) Use if +3/8 in. is >20% and +% in.
is <30%
Particle-Size Distribution:

I 43:54:3|
GR:SA:FI
Atterberg Limits:

LL, PL, Pl
129.0
136.5
Optimum Moisture Content (%)Corrected Moisture Content (%)

9.5 7.5
140.0
SP. GR. = 2.70SP.GR. =2.75 k SP.GR. =2.80
135.0 \ \
MV
cu \ a^ ^\ ^ ^•H 130.0 \\\
<u
QQ
£' R \N\\\
\1\\
125.0 ^
^
\'

0.0 120.0

5.0 10.0 15.0
Moisture Content (%)
20 MXTP-1,B-2@3-8
«Leighton MODIFIED PROCTOR COMPACTION TEST ASTM D 1557
Civiltec/PWP Explorer Well and Behner
Plant Improvements Tested By: 0. Figueroa
Input By: J. WardDepth (ft.): 2-5
11877.001
Date:Date:
01/04/18
01/09/18
Project Name:Project No.:

Boring No.: TP-2
Sample No.: B-2
Soil Identification: Dark brown poorly-graded sand with silt and gravel (SP-SM)g Note: Corrected dry density calculation assumes specific gravity of 2.70 and moisture content of 1.0%,fQLOversLze_rnateriai
Preparation
Method:

Compaction
Method
xx
MoistDry
Mechanical RamManual Ram
Scalp Fraction (%)
#3/4#3/8
#4

27.3 Rammer Weight (Ib.)Height of Drop (in.)

10.018.0
Mold Volume (ft3) | 0.07450
TEST NO. 1 2 3 4 5 6
Wt. Compacted Soil + Mold (g) 7114 7313 7445 7449Weight of Mold (g) 2672 2672 2672 2672 Net Weight of Soil (9) 4442 4641 4773 4777
Wet Weight of Soil + Cont. (g) 760.9 742.6 803.8 880.9
Dry Weight of Soil + Cont. (g) 732.7 699.5 744.0 797.4
Weight of Container (g) 82.7 75.6 77.8 76.8
Moisture Content (%) 4.34 6.91 8.98 11.59Wet DensityDr/ Density _LpcQ_
(PCf)
131.4126.0
137.3128.5
141.2
129.6
141.4126.7
Maximum Dry Density (pcf)
Corrected Dry Density (pcf)
Procedure A
Soil Passing No. 4 (4.75 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers: 5 (Five)Blows per layer: 25 (twenty-five)
May be used if +#4 is 20% or less
Procedure B
Soil Passing 3/8 in. (9.5 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers: 5 (Five)
Blows per layer: 25 (twenty-five)
Use if +#4 is >20% and +3/8 in. is
20% or less
Procedure C
Soil Passing 3/4 in. (19.0 mm) Sieve
Mold : 6 in. (152.4 mm) diameter
Layers: 5 (Five)
Blows per layer: 56 (fifty-six)
Use if +3/8 in. is >20% and +3/4 in.
is <30%
Particle-Size Distribution:

I 42:53:5 |
GR:SA:FI
Atterberg Limits:

LL, PL, Pl
129.5
138.0
Optimum Moisture Content (%)
Corrected Moisture Content (%)

9.0 7.0
140.0
SP. GR. = 2.70SP.GR. =2.75SP. GR. = 2.80 \'
\
135.0
cu^
sw 130.0
c \\\
s wQ \
£• ^ A \ Q ^
(^
^
125.0 \\\
\\N
A^
\\\
^\'

0.0 120.0

5.0 10.0 15.0
Moisture Content (%)
20 MXTP-2,B-2@2-5
€Leighton TESTS for SULFATE CONTENT CHLORIDE CONTENT and pH of SOILS Civiltec/PWP Explorer Well and Behner Plant
Project Name: Improvements Tested By :

Project No.: 11877.001 Data Input By:

G. Berdy Date: 01/03/18
J. Ward Date: 01/09/18
Boring No. TP-2
Sample No. B-l
Sample Depth (ft) 0.5-2Soil Identification: Dark brown SMWet Weight of Soil + Container (g) 225.23 Dry Weight of Soil + Container (g) 220.84
Weight of Container (g) 69.74
Moisture Content (%) 2.91
Weight of Soaked Soil (g) 100.12
SULFATE CONTENT, DOT California Test 417, Part II
Beaker No. 15
Crucible No, 17
Furnace Temperature (°C) 860
Time In / Time Out 8:00/8:45
Duration of Combustion (min) 45
Wt. of Crucible + Residue (g) 22.2088
Wt. of Crucible (g) 22.2074Wt. of Residue (g) (A) 0.0014 PPM of Sulfate (A)x 41150 57.61PPM ofSulfate, Dry Weight Basis 59 CHLORIDE CONTENT, DOT California Test 422
ml of Extract For Titration (B) 15
ml ofAgN03 Soln. Used in Titration (C) 0.8
PPM of Chloride (C -0.2) * 100 * 30/B 120PPM of Chloride, Dry Wt. Basis 124 pH TEST, DOT California Test 643
pH Value 5.57Temperature °C 21.3
€Leighton SOIL RESISTIVITY TEST DOT CA TEST 643
Project Name:Project No. :Boring No.:Sample No. :

Civiltec/PWP Explorer Well and Behner PlantImprovements11877.001 TP-2
Tested By :

Data Input By:

Depth (ft.) :

G. Berdy Date: 01/03/18J. Ward Date: 01/09/18

0.5-2
B-l
Soil Identification:* Dark brown SM
•California Test 643 requires soil specimens to consist only of portions of samples passing through the No. 8 US Standard Sieve before resistivity testing. Therefore, this test method may not be representative for coarser materials.

Specimen
No.

Water
Added (ml)
(Wa)
1 10
Adjusted
Moisture
Content
(MC)
Resistance
Reading
(ohm)
Soil
Resistivity(ohm-cm)

10.80 97500 97500
2 20 18.70 33000 33000
3 30 26.60 34000 34000
45 Moisture Content (%) (MCi) 2.91
Wet Wt. of Soil + Cont. (g) 225.23
Dry Wt. of Soil + Cent. (g) 220.84Wt. of Container (g) 69.74 Container No.

Initial Soil Wt. (g) (Wt) 130.30
Box Constant 1.000
MC=(((l+Mci/100)x(Wa/Wt+l))-l)xlOO
Min. Resistivity
(ohm-cm)
Moisture Content
(%)
Sulfate Content
(ppm)
Chloride Content
(ppm)
Soil pH
PH Temp. (°C)
DOT CA Test 643 DOT CA Test 417 Part II DOT CA Test 422 DOT CA Test 643 28000 21.5 59 124 5.57 21.3
120000
100000
§
E
X:
0 :i
(flw
01 0)
80000
6000040000
20000
0 5.0
5 x
\
^
^
s
x
x
x
s

10.0 15.0 20.0
Moisture Content (%)

25.0 30.0
APP x c
;ARTHWORK AND GRADING

GUIDE SPECIFICATIONS
C-1
^Leighton
APP x c
ARTHWO

LEIGHTON CONSULTING, I

AND GRADING GUIDE SP
c.CIFICATIO s

TABLE OF CONT TS
Section
C-1.0 GENERAL.

Appendix C Page
,1
C-1.1 Intent.

C-1.2 Role of Leighton Consulting, Inc..

C-1.3 The Earthwork Contractor
111
C-2.0 PREPARATION OF AREAS TO BE FILLED ..................................................... 2 C-2.1 Clearing and Grubbing ..................................................................................2 C-2.2 Processing..................................................................................................... 3C-2.3 Overexcavation .............................................................................................3C-2.4 Benching .......................................................................................................3 C-2.5 Evaluation/Acceptance of Fill Areas.............................................................. 3 C-3.0 FILL MATERIAL................................................................................................^ C-3.1 Fill Quality.....................................................................................................^ C-3.2 Oversize.......................................................................................................^C-3.3 Import...........................................................................................................^ C-4.0 FILL PLACEMENT AND COMPACTION ........................................................... 4 C-4.1 Fill Layers.....................................................................................................^C-4.2 Fill Moisture Conditioning.............................................................................. 5 C-4.3 Compaction of Fill.......................................................................................... 5 C-4.4 Compaction of Fill Slopes.............................................................................. 5C-4.5 Compaction Testing ......................................................................................5 C-4.6 Compaction Test Locations........................................................................... 5 C-5.0 EXCAVATION..................................................................................................... 6C-6.0 TRENCH BACKFILLS........................................................................................ 6 C-6.1 Safety............................................................................................................ 6C-6.2 Bedding and Backfill...................................................................................... 6 C-6.3 Lift Thickness ................................................................................................ 7 C-1 .

G RAL
C-1.1 Intent
These Earthwork and Grading Guide Specifications are for grading and earthwork shown on the current, approved grading plan(s) and/or indicated in the LeightonConsulting, Inc. geotechnical report(s). These Guide Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, theproject-specific recommendations in the geotechnical report shall supersede theseGuide Specifications. Leighton Consulting, Inc. shall provide geotechnical observationand testing during earthwork and grading. Based on these observations and tests, Leighton Consulting, Inc. may provide new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s).

C-1.2 Role of Leighton Consulting, Inc.

Prior to commencement of earthwork and grading, Leighton Consulting, Inc. shall meet with the earthwork contractor to review the earthwork contractor's work plan, to schedule sufficient personnel to perform the appropriate level of observation, mappingand compaction testing. During earthwork and grading, Leighton Consulting, Inc. shallobserve, map, and document subsurface exposures to verify geotechnical designassumptions. If observed conditions are found to be significantly different than the interpreted assumptions during the design phase, Leighton Consulting, Inc. shall inform the owner, recommend appropriate changes in design to accommodate these observed conditions, and notify the review agency where required. Subsurface areas to be geotechnically observed, mapped, elevations recorded, and/or tested include (1) natural ground after clearing to receiving fill but before fill is placed, (2) bottoms of all "remedialremoval" areas, (3) all key bottoms, and (4) benches made on sloping ground to receive fill.

Leighton Consulting, Inc. shall observe moisture-conditioning and processing of thesubgrade and fill materials, and perform relative compaction testing of fill to determine the attained relative compaction. Leighton Consulting, Inc. shall provide Daily Field Reports to the owner and the Contractor on a routine and frequent basis.

C-1.3 The Earthwork Contractor
The earthwork contractor (Contractor) shall be qualified, experienced andknowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical report(s), and these Guide C-1
Leiahton Consultina, Inc. Earthwork and Grading Guide Specifications Specifications prior to commencement of grading.
responsible for performing grading and backfilling
approved plans and specifications.

The Contractor shall be solely
in accordance with the current,
The Contractor shall inform the owner and Leighton Consulting, Inc. of changes in workschedules at least one working day in advance of such changes so that appropriate observations and tests can be planned and accomplished. The Contractor shall notassume that Leighton Consulting, Inc. is aware of all grading operations.

The Contractor shall have the sole responsibility to provide adequate equipment and methods to accomplish earthwork and grading in accordance with the applicablegrading codes and agency ordinances, these Guide Specifications, and recommendations in the approved geotechnical report(s) and grading plan(s). If, in the opinion of Leighton Consulting, Inc., unsatisfactory conditions, such as unsuitable soil, improper moisture condition, inadequate compaction, adverse weather, etc., areresulting in a quality of work less than required in these specifications, LeightonConsulting, Inc. shall reject the work and may recommend to the owner that earthwork and grading be stopped until unsatisfactory condition(s) are rectified.

C-2.0 P PARATION OF A AS TO FILL
C-2.1 Clearing and Grubbing
Vegetation, such as brush, grass, roots and other deleterious material shall besufficiently removed and properly disposed of in a method acceptable to the owner,governing agencies and Leighton Consulting, Inc.. Care should be taken not toencroach upon or otherwise damage native and/or historic trees designated by theOwner or appropriate agencies to remain. Pavements, flatwork or other construction should not extend under the "drip line" of designated trees to remain.Leighton Consulting, Inc. shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than 3 percent oforganic materials (by dry weight: ASTM D 2974). Nesting of the organic materials shallnot be allowed.

If potentially hazardous materials are encountered, the Contractor shall stop work in theaffected area, and a hazardous material specialist shall be informed immediately forproper evaluation and handling of these materials prior to continuing to work in thatarea. As presently defined by the State of California, most refined petroleum products(gasoline, diesel fuel, motor oil, grease, coolant, etc.) have chemical constituents that C-2
Leiahton Consulting, Inc. Earthwork and Grading Guide Specifications are considered to be hazardous waste. As such, the indiscriminate dumping or spillageof these fluids onto the ground may constitute a misdemeanor, punishable by finesand/or imprisonment, and shall not be allowed.

C-2.2 Processing
Existing ground that has been declared satisfactory for support of fill, by LeightonConsulting, Inc., shall be scarified to a minimum depth of 6 inches (15 cm). Existing ground that is not satisfactory shall be over-excavated as specified in the following Section C-2.3. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasonably uniform, flat, and free of uneven features that would inhibit uniform compaction.

C-2.3 Overexcavation
In addition to removals and over-excavations recommended in the approved geotechnical report(s) and the grading plan, soft, loose, dry, saturated, spongy, organicrich, highly fractured or otherwise unsuitable ground shall be over-excavated tocompetent ground as evaluated by Leighton Consulting, Inc. during grading. All undocumented fill soils under proposed structure footprints should be excavated C-2.4 Benching
Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal tovertical units), (>20 percent grade) the ground shall be stepped or benched. The lowest bench or key shall be a minimum of 15 feet (4.5 m) wide and at least 2 feet (0.6 m) deep, into competent material as evaluated by Leighton Consulting, Inc.. Other benches shall be excavated a minimum height of 4 feet (1.2 m) into competent material or as otherwise recommended by Leighton Consulting, Inc.. Fill placed on groundsloping flatter than 5:1 (horizontal to vertical units), (<20 percent grade) shall also be benched or otherwise over-excavated to provide a flat subgrade for the fill.

C-2.5 Evaluation/Acceptance of Fill Areas
All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to beingaccepted by Leighton Consulting, Inc. as suitable to receive fill. The Contractor shallobtain a written acceptance (Daily Field Report) from Leighton Consulting, Inc. prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas, keys and benches.

C-3
Leiahton Consultinci, Inc. Earthwork and Grading Guide Specifications C-3.0 FILL AT AL
C-3.1 Fill Quality
Material to be used as fill shall be essentially free of organic matter and other deleterious substances evaluated and accepted by Leighton Consulting, Inc. prior to placement. Soils of poor quality, such as those with unacceptable gradation, highexpansion potential, or low strength shall be placed in areas acceptable to LeightonConsulting, Inc. or mixed with other soils to achieve satisfactory fill material.

C-3.2 Oversize
Oversize material defined as rock, or other irreducible material with a maximum dimension greater than 6 inches (15 cm), shall not be buried or placed in fill unless location, materials and placement methods are specifically accepted by LeightonConsulting, Inc.. Placement operations shall be such that nesting of oversized material does not occur and such that oversize material is completely surrounded by compactedor densified fill. Oversize material shall not be placed within 10 feet (3 m) measuredvertically from finish grade, or within 2 feet (0.61 m) of future utilities or underground construction.

C-3.3 Import
If importing of fill material is required for grading, proposed import material shall meet the requirements of Section C-3.1, and be free of hazardous materials ("contaminants") and rock larger than 3-inches (8 cm) in largest dimension. All import soils shall have an Expansion Index (El) of 20 or less and a sulfate content no greater than (^) 500 partsper-million (ppm). A representative sample of a potential import source shall be given to Leighton Consulting, Inc. at least four full working days before importing begins, so that suitability of this import material can be determined and appropriate tests performed.

C-4.0 FILL PLAC T A COMPACTIO
C-4.1 Fill Layers
Approved fill material shall be placed in areas prepared to receive fill, as described inSection C-2.0, above, in near-horizontal layers not exceeding 8 inches (20 cm) in loosethickness. Leighton Consulting, Inc. may accept thicker layers if testing indicates thegrading procedures can adequately compact the thicker layers, and only if the building officials with the appropriate jurisdiction approve. Each layer shall be spread evenly and mixed thoroughly to attain relative uniformity of material and moisture throughout.

C-4
Leiahton Consulting, Inc. Earthwork and Grading Guide Specifications C-4.2 Fill Moisture Conditioning
Fill soils shall be watered, dried back, blended and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly over optimum. Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM) Test Method D 1557.

C-4.3 Compaction of Fill
After each layer has been moisture-conditioned, mixed, and evenly spread, each layer shall be uniformly compacted to not-less-than (s) 90 percent of the maximum dry density as determined by ASTM Test Method D 1557. In some cases, structural fill may be specified (see project-specific geotechnical report) to be uniformly compacted to atleast (s) 95 percent of the ASTM D 1557 modified Proctor laboratory maximum dry density. For fills thicker than (>) 15 feet (4.5 m), the portion of fill deeper than 15 feet below proposed finish grade shall be compacted to 95 percent of the ASTM D 1557laboratory maximum density. Compaction equipment shall be adequately sized and beeither specifically designed for soil compaction or of proven reliability to efficientlyachieve the specified level of compaction with uniformity.

C-4.4 Compaction of Fill Slopes
In addition to normal compaction procedures specified above, compaction of slopes shall be accomplished by back rolling of slopes with sheepsfoot rollers at increments of3 to 4 feet (1 to 1.2 m) in fill elevation, or by other methods producing satisfactoryresults acceptable to Leighton Consulting, Inc.. Upon completion of grading, relativecompaction of the fill, out to the slope face, shall be at least 90 percent of the ASTM D 1557 laboratory maximum density.

C-4.5 Compaction Testing
Field-tests for moisture content and relative compaction of the fill soils shall be performed by Leighton Consulting, Inc.. Location and frequency of tests shall be at our field representative(s) discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. Test locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to inadequate compaction (such as close to slope faces and at the fitl/bedrock benches).

C-4.6 CpmpactlQn Test Locations
Leighton Consulting, Inc. shall document the approximate elevation and horizontal coordinates of each density test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that Leighton C-5
Leighton Consulting, Inc. Earthwork and Grading Guide Specifications Consulting, Inc. can determine the test locations with sufficient accuracy. Adequate grade stakes shall be provided.

C-5.0 EXCAVATION
Excavations, as well as over-excavation for remedial purposes, shall be evaluated byLeighton Consulting, Inc. during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of removal shall be determined by Leighton Consulting, Inc. based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded, the cut portion of the slope shall be made, then observed and reviewed by Leighton Consulting, Inc. prior to placement of materials for construction of the fill portion of the slope, unlessotherwise recommended by Leighton Consulting, Inc..

C-6.0 T c ACKFILLS
C-6.1 Safety
The Contractor shall follow all OSHA and Cal/OSHA requirements for safety of trench excavations. Work should be performed in accordance with Article 6 of the California Construction Safety Orders, 2015 Edition or more current (see also: http://www.dir.ca.gov/title8/sb4a6.html).

C-6.2 Bedding and Backfill
All utility trench bedding and backfill shall be performed in accordance with applicable provisions of the 2015 Edition of the Standard Specifications for Public Works Construction (Green Book). Bedding material shall have a Sand Equivalent greater than 30 (SE>30). Bedding shall be placed to 1-foot (0.3 m) over the top of the conduit, and densified by jetting in areas of granular soils, if allowed by the permitting agency.

Otherwise, the pipe-bedding zone should be backfilled with Controlled Low StrengthMaterial (CLSM) consisting of at least one sack of Portland cement per cubic-yard ofsand, and conforming to Section 201-6 of the 2015 Edition of the StandardSpecifications for Public Works Construction (Green Book). Backfill over the beddingzone shall be placed and densified mechanically to a minimum of 90 percent of relative compaction (ASTM D 1557) from 1 foot (0.3 m) above the top of the conduit to thesurface. Backfill above the pipe zone shall not be jetted. Jetting of the bedding around the conduits shall be observed by Leighton Consulting, Inc. and backfill above the pipezone (bedding) shall be observed and tested by Leighton Consulting, Inc..

C-6
Leiahton Consulting, Inc. Earthwork and Grading Guide Specifications C-6.3 Lift Thickness
Lift thickness of trench backfill shall not exceed those allowed in the StandardSpecifications of Public Works Construction unless the Contractor can demonstrate to Leighton Consulting, Inc. that the fill lift can be compacted to the minimum relativecompaction by his alternative equipment and method, and only if the building officialswith the appropriate jurisdiction approve.

C-7
Appendix D
Noise Calculations

APPENDIX D

NOISE CALCULATIONS
File Name on Meter
File Name on PC
Serial Number
Model
Firmware VersionUser
LocationJob Description
Note
831_Data.590.s
831_0001742-20230726113759-831_Data.590.1dbin
0001742
Model 831

2.300
Descriptii
StartStop
Duration
Run Time
Pause
2023-07-26 11:37:59
2023.07-27 12:04:53
24:26:54.19524:26:51,797
00:00:02.4
Pre-CaIibration
Post-CaIlbrationCalibration Deviatii
2023-07-26 11:36:43
None
RMS WeightPeak WeightDetectorPreamplifierMicrophone CorrectionIntegration MethodGain Overload
Under Range PeakUnder Range LimitNoise Floor
A WeightingA Weighting
Stow
PRM831
Off
Linear

0.0 dB
141.9 dB
A

74.325.9

16.8 c

71.326.1

16.9 z

76.3 dB31.2 dB22.0 dB
LA.q
LAEEALApeak [max]LASmax
LASmln
SEA

54.6 104.02.812 mPa2h
2023-07-27 12:04:46
2023-07-27 12:04:16
2023-07-26 18:40:46
dB
111.7 dB

82.3 dB

47.3 dB
LAS > 60.0 dB (Exceedance Counts / Duration)
LAS > 90.0 dB (Exceedance Counts / Duration)LApeak > 135.0 dB (Exccedance Counts / Duration)LApeak > 137.0 dB (Exceedance Counts / Duration)LApeak > 140.0 dB (Exceedance Counts / Duration)Community Noise 169
00 0
Ldn

60.4 U29.9 s

0.0 s0.0 s

0.0 s0.0 s
LDay 07:00-22:00

55.0 LNight 22:00-07:00

53.7 Lden LDay 07:00-19:00 LEvening 19:00-22:00 LNight 22:00-07:00

60.6 55.2 54.3 53.7
LCt,
LAeq
LCcq . LA.qLAIeqlA,q
LAleq - LAeq
L.q
Ls(max)LFtmax)Llfmax)Ls(min)tFlminlLl(min)Lpeak(max)
Overload Count
Overload Duration

63.0 dB54.6 dB

8.4 dB

57.5 dB

54.6 d8

2.9 dB
A

54.6 dB | Time Stamp82.31 2023/07/27 12:04:4689.1! 2023/07/27 12:04:4693.2; 2023/07/27 12:04:4647.31 2023/07/26 18:40:46

45.847.2
2023/07/27 12:04:482023/07/27 11:54:51
111.7! 2023/07/27 12^4:46

0.0 s
c
dB

63.0;
Time Stamp dB
104.8

97.1i 2023/07/26 11:38:29
2023/07/26 11:38:28

72.4 118.9
109.3i 2023/07/26 11:38:28

57.8 56.6
2023/07/27 2:41:20
2023/07/26 18:40:44

57.9i 2023/07/27 2:41:19
117.61 2023/07/26 11:38:28
124
Time Stamp
2023/07/26 11:38:29
127.0
^ 2023/07/26 11:38:29

60.1 58.4
2023/07/26 11:38:29
2023/07/27 2:41:20
2023/07/26 23:54:04

60.6 128.2
2023/07/26 23:54:312023/07/26 11:38:29
LA11.70
LA18.30
LA110.00LA125.00LA150.00LA17S.OO

58.7 dB

56.3 dB56.0 dB

54.6 dB53.1 dB52.0 dB
Preamp
PRM831
PRM831
PRM831PRM831
PRM831
PRM831
PRM831PRM831PRMS31
PRM831PRM831
Date
2023-07-26 11:36:43
2023-07-26 09:12:03
2023-04-12 17:02:152023-04-12 15:24:122023-01-05 15:03:02 2023-01-05 14:37:592022-02-04 11:33:49
2022-02-04 11:09:372022-02-03 21:24:11
2022-02-03 21:05:222021-09-21 15:55:26
dB re. IV/Pa
-24.33.24.39
-24.62-24.75
-24.38.24.32
-24.44-24.43-24.42
.24.39.24.26

6.3 8.0 10.0 12.5
File Name on Meter
File Name on PCSerial NumberModelFirmware VersionUserLocation Job Description
Note
831_Data.591.s
83l_0001742-20230727123941-831_Data.591.1dbin
0001742
Model 831

2.300
Description
StartStopDurationRun TimePause
2023-07-27 12:39;41
2023-07-28 14:14:48
25:35:07.10225:35:03.102
00:00:04.0
Pre-CalibratianPort-Calibration
Calibration Deviation
2023-07-26 11:36:43
None
RMS WeightPukWeilht
Detector
Preamplifier
Microphone CorrectionIntegration MethodGainOverload
Under Range PeakUnder Range Limit
Noise Floor
A Weighting
A Weightlne
Slow
PRM831
Off
Linear

0.0 dB
141.9 dB
A

74.325.9

16.8 c

71.3 26.1

16.9 z

76.3 dB31.2 dB22.0 dB
LA«i
LAEEA
LAp..k|m«|LASma.

LASminSEA

55.5 105.13.611 mPa2h
2023-07-27 12:40:14
2023-07-27 12:40:14
2023-07-28 11:14:55
134.4 dB
124.4 dB

90.4 dB46.8 d8
LAS > 60.0 dB (Exceedance Counts / Duration)
LAS > 90.0 dB (Exceedance Counts / Duration)LApeak > 135.0 dB (Exceedance Counts / Duration)LApcak > 137.0 dB (Exceedance Counts / Duration)LApcak > 140.0 dB (Exceedance Counts / Duration) 119
1 000
2836.7 S

0.7 s

0.0 s0,0 s0.0 s
Community Noise Id n

60.2 LDay 07:00.22:00

56.3 light 22:00-07:00

53.2 Lden

60.5 LDay 07:00-19:00

56.7 LEvenine 19:00-22:00
54,3
light 22:00-07:00

53.2 dB
LC.qU«qLC.q - LA«]lAlxiLA«i
LAIeq - LAeq
L^
L5(max)
b'lmu)
Ltmax)
LS|m]n]
Lftmin)U(mln)
Lprklmul

66.9 dB55.5 dB11.4 dB60.8 dB

55.5 dB

5.3 dB
A
dB

55.5 Time Stamp

90.4[ 2023/07/27 12:40:1497.61 2023/07/27 12:40:14
102.21 2023/07/27 12:40:14

46.8| 2023/07/28 11:14:55
4G.1
46,8
124.4
2023/07/28 11:14:51
2023/07/28 11:14:51
2023/07/27 12;40:U
c
dB66.9
111.4
Time Stamp
2023/07/27 12:40:14
119.7124.1

58. 2023/07/27 12:40:142023/07/27 12:40:142023/07/27 22:56:53

57.6 58.9
132.3
2023/07/28 0:07:14
2023/07/27 22:56:53
2023/07/27 12:40:14
dB

74.8 118.4
Time Stamp
2023/07/27 12:40:14
125.2
130.1

60.4 2023/07/27 12:40:14
2023/07/27 12:40:14

59.060.9
137.9
2023/07/27 22:56:53
2023/07/28 0:02:15
2023/07/27 22^56:53^
2023/07/27 12:40:14
Overload Count
Overload Duration
0 0.0 s
LAI 1.70LA18.30
LA110.00
LA125.00
LA150.00LA175.00

61.3 dB

54.7 dB54.2 dB

52.4 dB51.3 dB

50.5 dB
Prcamp
PRM831
PRM831PRM831PRM831
PRM831PRM83]PRM83]PRM83]
PRM831
PRM83]PRM83]
2023-07-262023-07-262023-04-12
2023-04-12
2023-01-OS2023-01-052022-02-04
2022-02-04
2022-02-03
2022-02-032021-09-21
Dlf
11:36:4309:12:0317:02:1515:24:1215:03:0214:37:5911:33:4911:09:3721:24:1121:05:2215:55:26 dB n. 1V/P.
-24.33-24.39-24.62
-24.75
-24.38-24,32
-24.44-24.43
-24.42-24.39-24.26

6.3 a.o 10.0 12.5 16.0
Summary
File Name on MeterFile Name on PC
Serial NumberModel
Firmware Version
User
Location
Job DescriptionNote
b<T_Data.087.s
b<T_0004615-20230612095539-LxT_Data.087.1dbin
0004615
SoundTrack LxT*

2.301
Measurement
Description
StartStop
Duration
Run TimePause
2023-06-12 09:55:39
2023-07-27 13:15:04
24:56:18.898
24:56:16.0
00:00:02.9
Pre-CalibrationPost-CalibrationCalibration Deviation
2023-06-09 18:45:43
None
Overall Settings
RMS WeightPeak Weight
Detector
Preamplifier
Microphone Correction
Integration Method
Overload
Under Range PeakUnder Range LimitNoise Floor
A WeightingA Weighting
Slow
PRMb<Tl
Off
Linear
142.1 dB
A

98.336.2

23.5 c z

95.3 100.3 dB34.2 42.2 d8

24.0 31.4 dB
LAeqLAEEAEA8EA40
LApeak (max)
LASmax
LASmin
SEA
LAS > 85.0 dB (Exceedance Counts / Duration)LAS >115.0 dB (Exceedance Counts / Duration) LApeak > 135.0 dB (Exceedance Counts / Duration)LApeak > 137.0 dB (Exceedance Counts / Duration)LApeak > 140.0 dB (Exceedance Counts / Duration) LCeqLAeqLCeq - LAeqLAIeqLAeq
LAIeq - LAeq
Leq
Ls(max)

75.3 124.8
334.858 mPa2h
107.422 mPa2h537.109 mPa2h
2023-07-26 10:14:432023-07-26 10:14:542023-06-12 09:57:37 135.0 dB
3 0
0 00

65.7 dB75.3 dB
-9.6 dB

60.5 dB

75.3 dB
-14.8 dB
A
125.0 dB114.0 dB

35.3 dB

14.5 s

0.0 s

0.0s

0.0 s0.0s
dB

75.3 114.0
Time Stamp
c
dB
2023/07/26 10:14:54

65.7 Time Stamp | dB
z
Time Stamp
LS(min)
LPeak(max)
Overload CountOverload Duration

35.3 125.0
2023/06/12 9:57:37
2023/07/26 10:14:43
0 0.0s
Dose Settings
Dose NameExchange Rate
Threshold
Criterion Level
Criterion Duration
OSHA-1
5 9090
8 OSHA-2
5 dB
80 dB90 dB
8 h
DoseProjected Dose
TWA (Projected)TWA(t)Lep (t)

1.09 0.35

49.257.480.2

1.11 %

0.36 %

49.3 dB57.5 dB80.2 dB
Statistics
LA11.70LA18.30LA125.00
LA150.00
LA175.00LA190.00

59.7 dB

57.0 dB54.2 dB52.0 dB

51.0 dB50.2 dB
Preamp
PRMLxTl
PRMb(Tl
PRMbiTlPRMbcTlPRMLxTlPRMU(T1PRMLxTlPRMb(Tl
PRMblTl
PRMLxTl
PRMbcTl
2023-07-26
2023-07-212023-06-09
2023-06-092023-06-092023-06-092023-06-082023-06-082023-06-082023-05-09 2022-06-01
Date
10:15:0714:00:2518:45:43
16:29:48
14:28:31
12:27:5913:24:0011:05:5910:50:5509:32:2416:13:21
dB re. IV/Pa
-48.36
-48.38-48.39
-48.32
-48.33-48.38
-48.34-48.36-48.32-48.31-48.06

6.3 8.0 10.0
Summary
File Name on MeterFile Name on PCSerial NumberModelFirmware Version User
Location
Job DescriptionNote
LxT_Data.088.s
b<T_0004615-20230727135602-LxT_Data.088.1dbin
0004615
SoundTrack b<T"

2.301
Measurement
Description
Start
Stop
DurationRun TimePause
2023-07-27 13:56:02
2023-07-28 15:30:40
25:33:03.94
25:32:58.297
00:00:04.8
Pre-CalibrationPost-CalibrationCalibration Deviation
2023-07-26 10:15:07
None
Overall Settings
RMS Weight
Peak Weight
DetectorPreamplifierMicrophone CorrectionIntegration Method Overload
Under Range PeakUnder Range LimitNoise Floor
A WeightingA Weighting
Slow
PRMLxTl
Off
Linear
142.1 dB
A

98.336.2

23.5 c

95.334.2

24.0 z
100.3

42.231.4
Results
LAeqLAEEAEA8EA40
LApeak (max)LASmax
LASmin
SEA

55.8 105.43.870 mPa2h1.212 mPa2h

6.059 mPa2h
2023-07-27 13:59:152023-07-28 05:58:532023-07-27 13:57:59 dB
109.5 dB

89.0 dB

46.8 dB
LAS > 85.0 dB (Exceedance Counts / Duration)
LAS > 115.0 dB (Exceedance Counts / Duration)LApeak > 135.0 dB (Exceedance Counts / Duration)LApeak > 137.0 dB (Exceedance Counts / Duration)LApeak > 140.0 dB (Exceedance Counts / Duration) 1 0000

5.7 s0.0 s

0.0 s

0.0 s
/
LCeqLAeq
LCeq - LAeq
LAIeqLAeq
LAIeq - LAeq
Leq
Ls(max)
Ls(min)
Lpeak(max)
Overload CountOverload Duration

64.6 dB55.8 dB

8.8 dB

60.0 dB55.8 dB

4.2 dB
A
dB55.8
Time Stamp

89.046.8
109.5
2023/07/28 5:58:53
2023/07/27 13:57:592023/07/27 13:59:15
0 0.0 s
(
dB

64.61 Dose Settings
Dose NameExchange Rate
Threshold
Criterion LevelCriterion Duration
OSHA-1
5 9090
8 OSHA-2
5 dB
80 dB90 dB
8 h
DoseProjected Dose
TWA (Projected)TWA (t)Lep (t)
Statistics
LA11.70LA18.30LA125.00LA150.00LA175.00LA190.00

60.8 60.0 dB55.3 dB52.8 dB51.6 dB50.9 dB50.3 dB

0.03 %0.01 %

23.1 dB31.4 dB60.8 dB
Calibration History
Preamp
PRMLxTlPRMLxTlPRMLxTlPRMLxTlPRMLxTlPRMLxTlPRMLxTlPRMLxTl PRMLxTlPRMLxTlPRMLxTl
2023-07-262023-07-21
2023-06-09
2023-06-092023-06-092023-06-092023-06-08
2023-06-082023-06-082023-05-092022-06-01
Date
10:15:0714:00:2518:45:4316:29:4814:28:3112:27:5913:24:0011:05:5910:50:5509:32:2416:13:21 dB re. IV/Pa
-48.36-48.38
-48.39
-48.32-48.33-48.38-48.34-48.36-48.32-48.31-48.06
Sensitive Receptor to Project Site Approximate Distance (ft.) Anticipated Noise Level, dBA Explorer Well
|Gabrielino Trail (Explorer Road)
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
INearest House
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
I Odyssey Charter School
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
|Hathaway-Sycamores (El Nido Campus)
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
|Altadena Staples
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
[Sacred Heart Catholic Church
Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
|JPL East P.L.

Asphalt Demolition
Drilling & Well Development
Equipment Installation
Site Development
Noise Barriers
90 195 .
12301190
580
2130
600
798079797972737372735657575657
5657575657
63 636363635152525152
62 6363
6263
Noise Element suggest CNEL is 65 dBA at Residential (multi )/IVIixed Commercial locations, CNEL 60 dBA (low density),65 for Churches/Schools, 70 for Playgrounds, 75 for Riding Staples and Industrial manufacturing land-uses. Based on8 hr work site, noise levels are capped to 69 dBA, 64 dBA, 69 dBA, 74 dBA and 79 dBA for compliance with clearlyacceptable. formally Acceptable per the Noise Element suggests CNEL is 70 dBA for Residential/Schools land-uses.iThere is no threshold for Playrounds/Riding Staples and Industrial has an 80 dBA threshold.

Sensitive Receptor to Project Site Approximate Distance (ft.) Anticipated Noise Level, dBA Raw Water Pipelines
Gabrielino Trail (Explorer Road)
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
Nearest HouseOdyssey Charter School
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
Hathaway-Sycamores (El Nido Campus)
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
Altadena Staples
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
ISacred Heart Catholic Church
Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
JPL East P.L.

Asphalt Demolition
Excavation/Trenching
Well Site Piping Construction
90 195
1230
1190
580
2130
600
79797972737356
5757
56 5757636363515252626363
Noise Element suggest CNEL is 65 dBA at Residential (multi )/Mixed Commercial locations, CNEL 60 dBA (low density),65 for Churches/Schools, 70 for Playgrounds, 75 for Riding Staples and Industrial manufacturing land-uses. Based on8 hr work site, noise levels are capped to 69 dBA, 64 dBA,69 dBA, 74 dBA and 79 dBA for compliance with clearlyacceptable. iNormally Acceptable per the Noise Element suggests CNEL is 70 dBA for Residential/Schools land-uses.iThere is no threshold for Playrounds/Riding Staples and Industrial has an 80 dBA threshold.

Appendix E
Special Status Species Potentially Occurring in the Region

APPENDIX E

SPECIAL STATUS SPECIES POTENTIALLY

OCCURRING IN THE REGION
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name Common Name USFWS CDFW CRPR Species Background Potential Arctostaphylosglandulosa ssp.gabrielensis
San Gabrielmanzanita 18.2
Evergreen shrub. Rocky soil in chaparral; 1,952-4,920 ft. Southern California County Distribution: LosAngeles, San Bernardino. Blooming period: March Not expectedto occur;outside currentknownelevationalrange.

Astragalus brauntonii Braunton's milk- vetch FE 1B.1
Perennial herb. Recently burned and disturbed areas,in sandstone and carbonite soils, in chaparral, coastalscrub, and grasslands; 13-2,099 ft. SouthernCalifornia County Distribution: Los Angeles, Orange,Riverside, Ventura. Blooming period: January-August Not expectedto occur; nosuitablehabitat.

Atriplex parishii
Parish'sbrittlescale 1B.1
Annual herb. Alkaline soils in chenopod scrub, playas,and vernal pools; 82-6,232 ft. Southern CaliforniaCounty Distribution: Los Angeles (Presumedextirpated), Orange (Presumed extirpated), Riverside,San Bernardino (Presumed extirpated), San Diego.Blooming period: June-October Not expectedto occur; nosuitablehabitat.

Berberis nevinii Nevin's barberry FE SE 1B.1
Evergreen shrub. Sandy or gravelly soils in chaparral,cismontane woodland, coastal scrub, and riparianscrub; 898-2,707 ft. Southern California CountyDistribution: Los Angeles, Riverside, San Bernardino,San Diego. Blooming period: March-June Not expectedto occur; nosuitablehabitat.

Calochortus clavatusi/ar. gracilis
slendermariposa lily 1B.2
Perennial bulbiferous herb. Chaparral, coastal scrub,grassland; 1,050-3,280 ft. Southern California CountyDistribution: Los Angeles, Ventura. Blooming period:March-June Not expectedto occur; nosuitablehabitat.

E-l
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name Common Name USFWS CDFW CRPR Species Background Potential Calochortus palmerivar. palmeri
Palmer'smariposa lily 1B.2
Perennial bulbiferous herb. Mesic soils in chaparral,lower montane coniferous forests, meadows andseeps; 3,280-7,839 ft. Southern California CountyDistribution: Kern, Los Angeles, Riverside, SanBernardino, Ventura. Blooming period: April-July Not expectedto occur; nosuitablehabitat.

Calochortusplummerae
Plummer'smariposa lily 4.2
Perennial bulbiferous herb. Granitic and rocky areasin chaparral, cismontane woodland, coastal scrub,lower montane coniferous forest, and grassland; 328-5,576 ft. Southern California County Distribution: LosAngeles, Orange, Riverside, San Bemardino,Ventura. Blooming period: May-July Not expectedto occur; nosuitablehabitat.

Castilleja gleasoni Mt. Gleason paintbrush SR 1B.2
Hemiparasitic perennial herb. Granitic soils inchaparral, lower montane coniferous forests, andPinyon and juniper woodland; 3,805-7,118 ft.Southern California County Distribution: Los Angeles.Blooming period: May-September Not expectedto occur;outside currentknownelevationalrange.

Centromadia parryissp. austral/s southern tarplant 1B.1 Annual herb. Found within the margin of marshes andswamps, vernally mesic soils in grassland, and vernalpools; 0-1,574 ft. Southern California CountyDistribution: Los Angeles, Orange, San Diego,Ventura. Blooming period: May-November Not expectedto occur; nosuitablehabitat.

Centromadiapungens ssp. /aev/s smooth tarplant 1B.1
Annual herb. Alkaline soils in chenopod scrub,meadows and seeps, playas, riparian woodland, andgrassland; 0-2,100 ft. Southern California CountyDistribution: Los Angeles, Riverside, San Bernardino,San Diego. Blooming period: April-September Not expectedto occur; nosuitablehabitat.

E-2
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name Common Name USFWS CDFW CRPR Species Background Potential Chorizanthe parryivar. fernandina
San FernandaValleyspineflower
FC SE 1B.1
Annual herb. Sandy soil in coastal scrub andgrassland; 492-4,002 ft. Southern California CountyDistribution: Los Angeles, Orange (Presumedextirpated), Ventura. Blooming period: April-July Not expectedto occur; nosuitablehabitat.

Chorizanthe parryivar. parry i
Parry'sspineflower 1B.1
Annual herb. Sandy or rocky openings in chaparral,coastal scrub, cismontane woodland, and grassland;902-4,001 ft. Southern California County Distribution:Los Angeles, Riverside, San Bernardino. Bloomingperiod: April-June Not expectedto occur; nosuitablehabitat.

Cladium californicum California
sawgrass
2B.2
Perennial rhizomatous herb. Meadows, seeps,marshes, and swamps either alkaline or freshwater;197-2,837 ft. Southern California County Distribution:Los Angeles (Presumed extirpated), Riverside, SanBernardino. Blooming period: June-September Not expectedto occur; nosuitablehabitat.

Dodecahemaleptoceras
slender-hornedspineflower FE SE 1B.1
Annual herb. Sandy soils in chaparral, cismontanewoodland, and alluvial fan coastal scrub; 656-2,493ft. Southern California County Distribution: LosAngeles, Riverside, San Bernardino. Blooming period:April-June Not expectedto occur; nosuitablehabitat.

Dudleya multicaulis many-stemmed dudleya 1B.2
Perennial herb. Often in clay soils in chaparral,coastal scrub, and grassland; 49-2,591 ft. SouthernCalifornia County Distribution: Los Angeles, Orange,Riverside, San Bernardino, San Diego. Bloomingperiod: April-July Not expectedto occur; nosuitablehabitat.

Galium grande San Gabriel bedstraw 1B.2
Deciduous shrub. Chaparral, cismontane woodland,broadleafed upland and lower montane coniferousforest; 1,394-4,920 ft. Southern California CountyDistribution: Los Angeles. Blooming period: JanuaryJuly Not expectedto occur; nosuitablehabitat.

E-3
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name Common Name USFWS | CDFW | CRPR Species Background Potential Helianthus nuttalliissp. parish/'/'
Los Angelessunflower 1A
Perennial rhizomatous herb. Coastal salt andfreshwater marshes and swamps; 33-5,494 ft. | Not expectedSouthern California County Distribution: Los Angeles | to occur; no(Presumed extirpated), Orange (Presumed | suitableextirpated), San Bernardino (Presumed extirpated). | habitat.Blooming period: August-October Horkelia cuneata var.puberula mesa horkelia 1B.1
Perennial herb. Sandy and gravelly soils in maritimechaparral, cismontane woodland, and coastal scrub;229-2.657ft. Southern California County Distribution:Los Angeles, Orange, Riverside (Presumedextirpated), San Bernardino, San Diego (Presumedextirpated), Ventura. Blooming period: February-JuIy(September) Not expected
to occur; nosuitablehabitat.

Imperata brevifolia California satintail 28.1
Perennial rhizomatous herb. Mesic soils in chaparral,coastal scrub, Mojavean desert scrub, riparian scrub,meadows and seeps (often alkali); 0-3,985 ft.Southern California County Distribution: Imperial,Kern, Los Angeles, Orange, Riverside, SanBernardino, Ventura. Blooming period: SeptemberMay Not expectedto occur; nosuitablehabitat.

Lasthenia glabratassp. coulteri
Coulter'sgoldfields 1B.1
Annual herb. Coastal salt marsh, coastal saltswamps, playas, vernal pools; 3-4,001 ft. SouthernCalifornia County Distribution: Kern (Presumedextirpated), Los Angeles (Presumed extirpated),Orange, Riverside, San Bernardino (Presumedextirpated), San Diego, Venture. Blooming period:February-June Not expected
to occur; nosuitablehabitat.

E-4
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name Common Name USFWS CDFW CRPR Species Background Potential Lepidium virginicumvar. robinsonii
Robinson'spepper-grass

4.3 Annual herb. Openings in chaparral and sage scrub;below 2,900 ft. Southern California CountyDistribution: Los Angeles, Orange, Riverside, SanBernardino, San Diego, Ventura. Blooming Period:January-July Not expectedto occur; nosuitablehabitat.

Linanthus concinnus San Gabriel linanthus 1B.2
Annual herb. Rocky openings in chaparral, lower andupper montane coniferous forest; 4,986-9,184 ft.Southern California County Distribution: Los Angeles,San Bernardino. Blooming period: April-July Not expectedto occur;outside currentknownelevationalrange.

Malacothamnusdavidsonii
Davidson'sbush-mallow
1B.2
Deciduous shrub. Chaparral, coastal scrub,cismontane and riparian woodland; 607-2,804 ft.Southern California County Distribution: Kern, LosAngeles, Ventura. Blooming period: June-January Not expectedto occur; nosuitablehabitat.

Pseudognaphaliumleucocephalum
white rabbittobacco 2B.2
Perennial herb. Sandy or gravelly soils in chaparral,cismontane woodland, coastal scrub, and riparianwoodland; 0-6,888 ft. Southern California CountyDistribution: Los Angeles, Orange, Riverside, SanDiego. Blooming period: July-December Not expectedto occur; nosuitablehabitat.

Ribes divaricatumvar. parishii
Parish'sgooseberry 1A
Deciduous shrub. Riparian woodland; 213-984ft.Southern California County Distribution: Los Angeles(Presumed extirpated), San Bernardino (Presumedextirpated). Blooming period: February-April Not expectedto occur; nosuitablehabitat.

Sidalceaneomexicana
salt springcheckerbloom 2B.2
Perennial herb. Alkaline and mesic soils in chaparral,coastal scrub, lower montane coniferous forest,Mojavean desert scrub, and playas; 49-5,020 ft.Southern California County Distribution: Kern, LosAngeles (Presumed extirpated), Orange, Riverside,San Bernardino, San Diego, Ventura. Bloomingperiod: March-June Not expectedto occur; nosuitablehabitat.

E-5
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-1

SPECIAL STATUS PLANT SPECIES

POTENTIALLY OCCURRING IN THE PROJECT REGION
Scientific Name I Common Name | USFWS | CDFW | CRPR Species Background Potential Symphyotrichumgreatae
Greata's aster 1B.3
Perennial rhizomatous herb. Mesic soils in chaparral,cismontane and riparian woodland, broadleavedupland and lower montane coniferious forest; 984-6,593ft. Southern California County Distribution: LosAngeles, San Bernardino, Ventura. Blooming period:June-October Not expectedto occur; nosuitablehabitat.

Species Background: California Native Plant Society (CNPS). 2023 (accessed November 7). Inventory of Rare and Endangered Plants (online edition, v9.5).Sacramento, CA: CNPS. http://www.rareplants.cnps.org/.Listing Status: California Department of Fish and Wildlife (CDFW). 2023 (October). Special Vascular Plants, Bryophytes, and Lichens List. Sacramento, CA: CDFW,Natural Heritage Division.USFWS: U.S. Fish and Wildlife Service; CDFW: California Department of Fish and Wildlife; CRPR: California Rare Plant Rank; ft: feetSpecies Status:Federal (USFWS)FE EndangeredFT Threatened State (CDFW)
SE EndangeredST Threatened
SR Rare
CRPR1A Plants presumed extirpated in California and either rare or extinct elsewhere1 B Plants Rare, Threatened, or Endangered in California and elsewhere2B Plants Rare, Threatened, or Endangered in California, but more common elsewhere4 Plants of limited distribution - watch listCRPR Threat Code ExtensionNone: Plants lacking any threat information.1 Seriously threatened in California (over 80% of occurrences threatened; high degree and immediacy of threat).2 Moderately threatened in California (20-80% of occurrences threatened; moderate degree and immediacy of threat).3 Not very threatened in California (<20% of occurrences threatened; low degree and immediacy of threat or no current threats known) E-6
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-2

SPECIAL STATUS WILDLIFE SPECIES REPORTED FROM THE PROJECT AREA Species General Habitat/Range Description USFWS CDFW
Critical
Habitat
Present in the
Study Area" Potential for Occurrence
InvertebratesBombus crotchii
Crotch bumble bee
Occurs in open grassland and scrubhabitats; nests underground. Feeds onmilkweed (Asclepias sp.), pincushion(Chaenactis sp,), lupine (Lupinus sp.),alfalfa (Medicago sp.), phacelia (Phaceliasp.), and sage [Salvia sp.).

CE Not expected to occur; no suitable habitat.

FishGila orcuttii
arroyo chub
Occurs in coastal freshwater streams andrivers with sustained flows and emergentvegetation with substrates consistingprimarily of sand or mud. ssc Not expected to occur; no suitable habitat.

Rhinichthys osculus ssp. 3
Santa Ana speckleddace
Occurs in perennial streams with rifflehabitats in clean, rocky-bottomed streamsand rivers. ssc Not expected to occur; no suitable habitat.

Catostomus santaanae
Santa Ana sucker
Occurs in shallow streams with flows thatrun from slow to swift. Stream substratesconsist of boulders, gravel, and cobblewhere there are growths of filamentousalgae. This species is occasionally foundon sandy or muddy substrates.

FT ssc No Not expected to occur; no suitable habitat.

Amphibians
Taricha torosa
Coast Range newt
Found in wet forests, oak forests,chaparral, and rolling grasslands. InSouthern California, drier chaparral, oakwoodland, and grasslands are used. ssc Not expected to occur; no suitable habitat.

E-7
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-2

SPECIAL STATUS WILDLIFE SPECIES REPORTED FROM THE PROJECT AREA Species General Habitat/Range Description | USFWS CDFW
Critical
Habitat
Present in the
Study Area" Potential for Occurrence
Anaxyrus californicus
arroyo toad
Occurs in semi-arid regions near washesor intermittent streams. Streams must beof low velocity with sand or gravelsubstrate.

FE ssc No Not expected to occur; no suitable habitat.

Rana draytonii
California red-legged
frog
Occurs in deep ponds and slow-movingstreams with emergent vegetation inforests, woodlands, grasslands, streams,wetlands, ponds, and lakes from sea levelto 8,000 feet above msl.

FT ssc No Not expected to occur; no
suitable habitat.

Rana muscosa
Southern Mountainyellow-legged frog
Occurs in small, isolated populations inthe San Gabriel, San Bernardino, and SanJacinto Mountains in narrow, rock-walledrivers, perennial creeks, and permanentplunge pools with intermittent creeks andpools in montane riparian and/or chaparralbetween 1,200 and 7,500 feet above msl.

FE ssc No Not expected to occur; no suitable habitat.

Spea hammondii
western spadefoot
Occurs in a wide range of habitats;lowlands to foothills, grasslands, openchaparral, pine-oak woodlands. It prefersshortgrass plains, sandy or gravelly soil(e.g., alkali flats, washes, alluvial fans). It isfossorial and breeds in temporary rainpools and slow-moving streams (e.g.,areas flooded by intermittent streams). ssc Not expected to occur; no suitable habitat.

ReptilesEmys marmorata
western pond turtle
Occurs in ponds, lakes, marshes, rivers,streams, and irrigation ditches with a rockyor muddy bottom and aquatic vegetation atelevations from sea level to approximately6,696 feet above msl.

FC ssc Not expected to occur; no suitable habitat.

E-8
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-2

SPECIAL STATUS WILDLIFE SPECIES REPORTED FROM THE PROJECT AREA Species General HabitaURange Description | USFWS CDFW
CriticalHabitat
Present in the
Study Area' Potential for Occurrence
Phrynosoma blainvillii
coast horned lizard
Occurs in scrubland, grassland, coniferousforests, and broadleaf woodland vegetationtypes. ssc
Not expected to occur;limited marginally suitablehabitat.

Aspidoscelis tigrisstejnegeri
San Diegan tigercoastalwhiptail
Occurs in hot and dry areas with sparsefoliage and open areas. Found in forests,woodland, chaparral, and riparian areas.

IVIay occur; potentiallysuitable habitat adjacent toProject boundary.

Anniella sp.

California legless lizard
Requires areas with loose sandy soil,moisture, warmth, and plant cover,including leaf litter. Occurs in coastal dune,valley-foothill, chaparral, and coastal scrubtypes at elevations between sea level andapproximately 1,800 m (6,000 ft). ssc Not expected to occur; no suitable habitat.

Arizona elegansoccidentalis
California glossy snake
Occurs most commonly in desert habitatsbut also occur in chaparral, sagebrush,valley-foothill hardwood, pine-juniper, andannual grass, elevation from below sealevel to 7,000 feet. Prefer open sandyareas with scattered brush, but also foundin rocky areas. ssc
Not expected to occur;limited marginally suitablehabitat Thamnophis hammondii
two-striped gartersnake
Occurs in wetlands, freshwater marsh, andriparian habitats with perennial water. ssc Not expected to occur; no suitable habitat.

E-9
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-2

SPECIAL STATUS WILDLIFE SPECIES REPORTED FROM THE PROJECT AREA Species General HabitaVRange Description | USFWS CDFW
Critical
Habitat
Present in the
Study Area" Potential for Occurrence
Birds
Gymnogyps californianus
California condor
Occurs in mountainous country at low tomoderate elevations, especially rocky andbrushy areas with cliffs available for nestsites. Foraging habitat includesgrasslands, oak savannas, mountainplateaus, ridges, and canyons. In lowerelevation mountains, they require areaswhere wind conditions are suitable fortake-offs.

FE SE No Not expected to occur; no suitable habitat.

Coccyzus amen'canusoccidentalis
western yellow-billed
cuckoo (nesting)
Uncommon to rare summer resident ofvalley foothill and desert riparian habitatsin scattered locations in California.Requires broad areas ofold-growthriparian habitats dominated by willows andcottonwoods with dense understoryvegetation.

FT SE No Not expected to occur; no suitable habitat.

Asia otus
long-eared owl (nesting)
Occurs in dense woodlands adjacent toopen grassland orshrubland, and openforests. ssc Not expected to occur; no suitable habitat.

Cypseloides niger
black swift
Nesting typically occurs in a moist creviceor cave on a sea cliff above the surf or oncliffs behind or adjacent to waterfalls indeep canyons. ssc Not expected to occur; no suitable habitat.

Empidonax traillii extimus
southwestern willowflycatcher
Occurs in riparian habitats along rivers,streams, or other wetlands where densegrowth of willows, mule fat, arrow-weed[Pluchea sericea), tamarisk [Tamarix sp.),or other plants are present, often with ascattered overstory of cottonwood FE SE No Not expected to occur; no suitable habitat.

E-10
Appendix E - Special Status Species Potentially Occurring in the Region TABLE E-2

SPECIAL STATUS WILDLIFE SPECIES REPORTED FROM THE PROJECT AREA Species General Habitat/Range Description USFWS CDFW
Critical
Habitat
Present in the
Study Area' Potential for Occurrence
Buteo swainsoni
Swainson's hawk
Forages in savanna, open pine-oakwoodland, and agricultural lands withscattered trees.

Pasadena City CouncilJuly 8, 2024

Pasadena City Council
July 8, 2024