Santa Clarita City Council
August 27, 2024

NOTICE OF EXEMPTION

TO: FROM:

[X] County Clerk City of Santa Clarita
County of Los Angeles Community Development
12400 E. Imperial Hwy., Rm. 2001 23920 Valencia Boulevard, Suite #302 Norwalk, CA 90650 Santa Clarita, CA 91355

[X] Office of Planning and Research
1400 Tenth Street
Sacramento, CA 95814
DATE: August 27, 2024

PROJECT NAME: Master Case 21 -086: Minor Use Permit 21 -012, Architectural Design Review 21 - 015, and Development Review 21-011

PROJECT APPLICANT: Harvard 826 Property, LLC

PROJECT LOCATION: 26111-26135 Bouquet Canyon Road
(Assessor’s Parcel Numbers 2811-003-016, -017, and -018)

PROJECT DESCRIPTION: The applicant, Harvard 826 Property, LLC, is requesting a Minor Use Permit (MUP) to construct the Promenade Flats Mixed -Use Project on a 1.2 -acre site at 26111 -26135 Bouquet Canyon Road. The project would construct a new four -story mixed -use building in the parking lot behind an existing restaurant building and would also construct a new parking lot on vacant land in the southwest corner of the commercial center. The new building would include 7,234 square feet of commercial space on the first floor with 30 one - bedroom apartments on the upper floors, along with rooftop amenity space for residents. Four of the apartments would be live-work units, providing an additional 1,640 square feet of commercial space. The project site is within the Mixed-Use Corridor (MXC) zone. The project was approved at an administrative hearing on April 17, 2024 and was then appealed to the Planning Commis sion. On June 18, 2024, the Planning Commission voted 4-1 to deny the appeal and affirm the project approval. Subsequently, Cornerstone Realty Advisors, on behalf of Cinema Park, LLC filed an appeal of the Planning Commission decision to the City Council.

This is to advise that the [ ] Hearing Officer [ ] Planning Commission [X] City Council of the City of Santa Clarita approved the above project on August 27, 202 4. Review of the project by the Ci ty Council found that the project is categorically exempt from additional environmental review under the California Environmental Quality Act.

EXEMPT STATUS: The project is exempt from additional review under the California Environmental Quality Act as a Class 32 In -Fill Development Projects categorical exemption, pursuant to CEQA Guidelines Section 15332. A Class 32 exemption consists of projects characterized as in-fill development.

Person or agency carrying out the project: City of Santa Clarita, Community Development Department

This is to certify that the Notice of Exemption with comments/responses and record of project approval is available for public review at:

City of Santa Clarita
Community Development Department
23920 Valencia Boulevard, Suite 302
Santa Clarita, California 91355
(661) 255-4330

Contact Person/Title: Andy Olson, Associate Planner

Signature:

MEMORANDUM
Date
: November 16, 2023
To: City of Santa Clarita Planning Department
From: Envicom Corporation, CEQA Environmental Consultants Subj: Assessment of Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01) This document has been prepared for the City of Santa Clarita, as the CEQA lead agency, for consideration of the proposed Santa Clarita Plaza Apartments Project (the project) located at 26111 Bouquet Canyon Road in the City of Santa Clarita as eligible for a Class 32 Categorical Exemption under the California Environmental Quality Act (CEQA) as an infill project . The following documentation and justifications have been compiled pursuant to the 2023 CEQA updates.

Categorical exemptions are defined in CEQA for various types of projects which the Secretary of the Resources Agency of the State of California has determined do not have a significant effect on the environment, and therefore are not subject to further environmental review under CEQA.

The Class 32 exemption (Section 15332 of the State CEQA Guidelines) is intended to promote infill development within urbanized areas. The class consists of environmentally benign infill projects, which are consistent with local general plan and zoning requirements.

Pursuant to Section 15332 of the State CEQA Guidelines, for a project to be eligible for a Categorical Exemption as a Class 32 In -fill Development project, it must meet the following conditions or “Criteria”:

A. The project is consistent with the applicable general plan designation and all applicable general plan policies as well as with applicable zoning designation and regulations.

B. The proposed development occurs within city limits on a project site of no more than five acres substantially surrounded by urban uses.

C. The project site has no value as habitat for endangered, rare or threatened species.

D. Approval of the project would not result in any significant effects relating to traffic, noise, air quality, or water quality.

E. The site can be adequately served by all required utilities and public services.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

In addition, pursuant to CEQA Section 15300.2, to qualify for a Class 32 Exemption under CEQA, none of the following “Exceptions” can apply to the project:

A. The project and successive projects of the same type in the same place will result in cumulative impacts.

B. There are unusual circumstances creating the reasonable possibility of significant effects.

C. The project may result in damage to scenic resources, including, but not limited to, trees, historic buildings, rock outcroppings, or similar resources, within an officially designated scenic highway.

D. The project is located on a site that the Department of Toxic Substances Control and the Secretary of the Environmental Protection have identified, pursuant to Government code section 65962.5, as being affected by hazardous wastes or clean-up problems.

E. The project may cause a substantial adverse change in the significance of an historical resource.

The justification for use of a Class 32 Categorical Exemption for the proposed project as an infill development in compliance with CEQA is provided below in the following format: I. Project Description, II. Evaluation of Class 32 Exemption Criteria, III. Consideration of Ex ceptions, and IV. Conclusion.

I. PROJECT DESCRIPTION
Existing Conditions
The project site comprises a total of approximately 1.2 acres located on an existing parking lot for the Santa Clarita Plaza, a small, one -story shopping center with an address of 26111 Bouquet Canyon Road in the Saugus community of the City of Santa Clarita . The project site is located between Santa Clarita Plaza to the south, Cinema Park shopping center to the north, the Las Flores Apartments to the west and an IHOP restaurant to the east. The proposed building is located on the same parcel as the IHOP restaurant. Access is provided from two existing driveways to Bouquet Canyon Road. Bouquet Canyon Road is a six -lane major arterial running north-south. It connects to Valencia Boulevard, a nine -lane major arterial, approximately 0.25 miles to the north. West of the intersection Valencia Boulevard curves south behind the project site approximately 0.25 miles away. Cinema Drive, a three-lane road located 200 feet north of the project site, runs east -west and connects Bouquet Canyon Road to Valencia Boulevard. Magic Mountain Parkway, another major arterial connects to Bouquet Canyon Road approximately .25 miles south.

The south fork of the Santa Clara River is approximately 400 feet west of the project site, and the Santa Clara River itself a little over .25 miles to the north. T o the east on the other side of Bouquet Canyon Road are railroad tracks and a series of hills. Apart from these physical barriers buildable land surrounding the project site is mostly developed. Industrial, light industrial, and commercial uses are located south of the site below Magic Mountain Parkway. Southwest of the site below the Parkway are large residential subdivisions. North and west of the site commercial developments appear to occupy all of the available buildable land.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Project
The proposed project consists of the construction, operation, and maintenance of a 52,418 square- foot, four -story mixed -use building with 26 one -bedroom residential units, four one -bedroom live/work units, and seven commercial suites. Total residential floor area is 43,512 square -feet and total commercial floor area is 14,394 square -feet. Commercial floor area includes 7,266 square-feet of commercial suites, 1,640 of live/work area, and 5,488 square -feet for the existing IHOP restaurant located on the east end of the parcel. The first floor of the new building will contain the commercial suites plus a residential lobby, the second and third floors will contain eight one-bedroom units, two live/work units, and a residential amenity room, the fourth floor will contain 10 one-bedroom units plus a terrace, and there will be a deck with BBQ area on the rooftop for residents. In addition to the mixed-use building 41 new parking spaces will be built on a 0.33-acre vacant parcel south of the project site behind (west) the Santa Clarita Plaza shopping center.

The project would require the following land use entitlements from the City of Santa Clarita:

• A Development Review (DR) to review the proposed development; • An Architectural Design Review (ADR) to review the proposed architecture; and, • Minor Use Permit (MUP) for development in the MXC zone that does not meet the minimum commercial square footage and for live/work quarters.

Construction
The site of the proposed building is previously developed, and the site of the proposed parking lot has been previously graded. The asphalt parking lot will be removed, but no import or export of soil is proposed as earthwork is expected to be balanced on site with existing soils excavated and recompacted.

II. EVALUATION OF CLASS 32 EXEMPTION CRITERIA
The following subsections provide discussion and analysis of the project’s consistency with the criteria listed in Section 15332 of the State CEQA Guidelines, for a project to be eligible for a Categorical Exemption as a Class 32 In-fill Development project.

A. The project is consistent with the applicable general plan designation and all applicable general plan policies as well as with applicable zoning designation and regulations.

The project site is zoned MXC (Mixed-Use Corridor), and the land use designation is Mixed-Use Corridor (MXC)

1. Both the zoning and the land use designation allow a residential density up to 30 dwelling units per acre and maximum FAR of 1.0 for a non -residential component. The proposed project has 25 units per acre and a FAR of approximately 0.27.

1 City of Santa Clarita, Mapping Your City application, Accessed June 21, 2023 at https://maps.santa- clarita.com/portal/apps/webappviewer/index.html?id=4b3cfb271314475db6518999b4747876 November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

The project meets the development standards for the zone and is contextually appropriate for the location given the existing adjacent commercial and residential uses , and there fore is consistent with the applicable policies and regulations of the General Plan and zoning designation and meets criteria A.

B. The proposed development occurs within city limits on a project site of no more than five acres substantially surrounded by urban uses.

The project site is approximately 1.2 acres and is located within an urbanized area within the City of Santa Clarita. The project site is an existing parking lot located between Santa Clarita Plaza shopping center to the south, Cinema Park shopping center to the north, the Las Flores Apartments to the west and an IHOP restaurant to the east. Physical barriers such as the Santa Clara River and its south fork to the north, south and west, and railroad tracks and hills to the east preclude development in those locations , but the area is otherwise nearly completely urbanized.

The area bordered by Valencia Boulevard to the north and west, Bouquet Canyon Road to the East, and Magic Mountain Parkway to the south , where the project site is located, is fully developed primarily with commercial uses, but also includes some multi-family residential south of the project site . East of Valencia Boulevard along Magic Mountain Parkway are a string of auto dealerships and more large commercial shopping centers. Therefore, the project meets criteria B.

C. The project site has no value as habitat for endangered, rare or threatened species.

The site of the proposed mixed-use building is a paved parking lot with some minor landscaping.

There is no potential habitat for endangered, rare or threatened species on the site. The vacant lot where the new parking will be constructed is surrounded by asphalt pavement and buildings and is covered in non-native annual grasses and ruderal species. There are no shrubs or trees or native flowering plants that may attract native species for nesting or feeding , and therefore no habitat that could potentially support some endangered, rare or threatened species , as these are species with specific habitat needs. The project therefore meets criteria C.

D. Approval of the project would not result in any significant effects relating to traffic, noise, air quality, or water quality.

Traffic Effects
The project would have a significant impact if it would conflict or be inconsistent with CEQA Guidelines section 150 64.3(b)(1) relating to Vehicle M iles Traveled (VMT). A transportation memorandum by LSA
2 determined, per the City’s Transportation Analysis Updates in Santa Clarita document published May 2020, that the project meets the City’s VMT screening criteria.

The Transportation Analysis Updates in Santa Clarita recommends that locally serving retail uses (less than 50,000 sf) and residential uses located in a low VMT area are screened from a VMT analysis. The project is located in a low VMT area and includes 8,906 square-feet of commercial floor space in the building (first floor commercial plus live/ workspace). If the existing IHOP

2 Transportation Memorandum for the Santa Clarita Plaza Project, LSA, April 28, 2022.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

restaurant located on the same parcel was included in the calculation the total would only amount to 14,394 square-feet, well below the screening criteria. Because construction traffic is temporary, there is no permanent increase in VMT and effectively no VMT related impacts. The memorandum discusses other transportation considerations but for the purposes of a Class 32 Categorical Exemption traffic impacts are limited to CEQA Guidelines section 15064.3(b)(1) .

Therefore, there would be no significant effects relating to traffic.

Noise Effects
A noise study was prepared for the project by LSA Associates to evaluate potential noise impacts expected to result from the proposed project.
3 Both construction and operational impacts were
assessed.

Existing Conditions
Short-term and long-term noise measurements were made in order to determine existing ambient noise levels in the vicinity of the project site. Short term noise measurements were conducted on a Wednesday and Thursday, January 25 and 26, 20 21 at three locations adjacent to the project site. Long term noise measurements were conducted on the same dates for 24 hours at two locations. The results are shown in Table 1, Project Site Ambient Noise Measurements.

Table 1
Project Site Ambient Noise Measurements
Number Location1 Leq2 Lmax3 Lmin4 Primary Noise Sources Short Term-1 26135 Bouquet
Canyon Road

69.1 84.0 52.0 Traffic on Bouquet Canyon Road
Short Term-2 26135 Bouquet
Canyon Road

51.8 66.4 46.2 Traffic on Bouquet Canyon Road
Short Term-3 26123 Bouquet
Canyon Road

52.3 71.4 44.6 Traffic on Bouquet Canyon Road
Number Location Leq CNEL5 Primary Noise Sources
Long Term-1 26135 Bouquet
Canyon Road

47.9-59.7 62.0 Traffic on Bouquet Canyon Road,
Metrolink trains, commercial activity.

Long Term-2 26135 Bouquet
Canyon Road

46.1-61.9 60.4 Traffic on Bouquet Canyon Road,
Metrolink trains, commercial activity.

Source: LSA Noise and Vibration Impact Analysis Memorandum, Attachment B. 1 See noise study for precise locations.
2 Leq is the average noise level equivalent to the energy content of the time period. 3 Lmax is the maximum measured sound level
4 Lmin is the minimum measured sound level
5 CNEL: Community Noise Equivalent Level, a weighted average of noise over a 24 hour period

3 LSA, Noise and Vibration Impact Analysis Memorandum for the proposed Promenade Flats Project at 26135 Bouquet Canyon Road in Santa Clarita, California, August 9, 2023 November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Noise Standards
Section 11.44.040 of the City’s Municipal Code has established daytime and nighttime exterior noise limits in regions designated as residential, and commercial and manufacturing, as shown in Table 2, Santa Clarita Maximum Exterior Noise Limits.

Table 2
Santa Clarita Maximum Exterior Noise Limits
Area Time Period dBA
Residential Day 7AM – 9PM 65
Night 9PM-7AM 55
Commercial &
Manufacturing
Day 7AM – 9PM 80
Night 9PM-7AM 70
Source: Santa Clarita MC Section 11.44.040

Construction
The Santa Clarita Municipal Code requires construction to take place between 7:00 AM to 7:00 PM on weekdays, 8:00 AM to 6:00 PM on Saturdays , and no construction is allowed on Sundays or national holidays (SCMC Section 11.44.080). The City does not set any limits on the level of construction noise, only allowed hours . Provided the project respects the allowed construction hours, as it must, it would comply with the standards . However, a significant increase in noise above accepted nuisance thresholds could constitute an impact. Therefore, project construction noise was estimated and compared to the 80 dBA Leq standard for noise impacts at a residential use utilized by the Federal Transit Administration (FTA). The FTA does not have jurisdiction over the project, however, it is helpful to compare the project to a standardized threshold to evaluate potential impacts.

The noise study calculates that the worst-case combined noise level during construction would be during the grading phase if/when a grader, bulldozer, and water truck are in use at the same time.

The combined noise generated during such a scenario would be 88 dBA Lmax at a distance of 50 feet from the active construction area. When the usage factor of the equipment is added to the equation (the percentage of time during construction that a piece of equipment is operating at full power, i.e., producing peak noise), the worst -case scenario drops to 84 dBA Leq at a distance of 50 feet. Noise energy dissipates over distance so any receptor further than 50 feet away would experience less noise than the projected Lmax and Leq. The nearest residences are approximately 175 feet west of the proposed new building, and 75 feet north of the proposed new parking lot.

Max noise emanating from the site of the new building would be 73 dBA Leq (77 Lmax) at the residences, and max noise emanating from the site of the new parking lot would be 78 dBA Leq (82 Lmax) at the residences. The average noise level (Leq) in both instances would be below the 80 dBA Leq FTA standard, therefore, project construction would not result in significant effects relating to noise.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Operation
The project will introduce new traffic trips to the area which will add to existing traffic noise, and introduce new stationary equipment, such as HVAC equipment, to the project site. Existing traffic noise on Bouquet Canyon Road was calculated in the Noise Study. With an estimated ADT (average daily trips) of 37,650 daily trips at 112 feet from the centerline of the road the noise level is calculated at 70 dBA CNEL. The project is anticipated to add 636 ADT to the area, resulting in an estimated 38,286 ADT. This increase would not change perceptible noise levels as a doubling of traffic is necessary to produce a 3 dBA increase in noise, which is a change perceptible to the human ear only in an enclosed environment. The addition of 636 ADT would only increase noise by 0.07 dBA and therefore would not be perceptible and not result in an impact. Noise generated by the coming -and-going of vehicles from the new development would add to noise in the existing driveways and parking lots, however, the amount of activity would not be intense enough to create a doubling of noise in the immediate area and should not create a perceptible increase in noise. Vehicles traveling at a slow speed, as through a parking lot, do not generate the same amount of noise as high speed traffic, and impacts from the general activity of the proposed project would not result in a significant noise impact.

New stationary noise sources introduced by the project would primarily be 40 new HVAC units on the rooftop. According to the noise study each commercial HVAC unit would generate a sound power level (SWL) that ranges between 76.0 dBA and 79.0 dBA, which would be equivalent to noise levels of 44.4 dBA Leq and 47.4 dBA Leq at a distance of 50 ft. Each HVAC unit associated with residential uses would generate a sound pressure level (SPL) ranging between 36.3 dBA Leq and 39.3 dBA Leq at a distance of 50 ft . The composite noise level of all 40 HVAC units would be 56.2 dBA at a distance of 50 ft. As the units are on top of the roof they are attenuated by the roofline, and the parapet surrounding the roofline, which would reduce noise by a minimum of 8 dBA. At the existing residential units the noise generated by HVAC units on the proposed building would result in 37.6 dBA Leq, and the nearest commercial structure would experience 49.1 dBA Leq. The amount of noise generated by HVAC units would therefore be below the noise measured (Leq) at each short- term monitoring location as shown in Table 1 .

Therefore, noise from the HVAC units would not result in a noticeable change in the intensity of noise (3 dBA or greater), would not violate City noise limits shown in Table 2, and would not result in a significant impact.

Therefore, as demonstrated, neither project construction nor project operation would not result in significant noise impacts.

Potential vibration impacts were also assessed in the noise study but are not presented here as they are not considered in the evaluation of a Categorical Exemption. The study found no significant impacts according to thresholds not applicable to the project’s Class 32 exemption.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Air Quality Effects
An air quality study was prepared for the project by LSA Associates to evaluate potential air quality impacts expected to result from the proposed project. 4 Both project construction and operations were assessed.

Air Quality
The primary regulator of air quality in the area is the South Coast Air Quality Management District (SCAQMD), the agency responsible for air pollution control within the South Coast Air Basin (SCAB), of which Los Angeles County is part of. Rules and regulations promulgated by the SCAQMD are derived from the federal Clean Air Act and state Clean Air Act which mimics the federal legislation and provides stricter controls in certain instances. The primarily regulatory and policy document the SCAQMD is tasked with implementing is the Air Quality Management Plan (AQMP) which is developed by the SCAQMD and the Southern California Association of Governments (SCAG). SCAG develops portions of the AQMP that address transportation control measures, land use, and growth projections within districts that have not met air quality standards.

The 2022 AQMP relies on the growth estimates and transportation control measures found in the SCAG 2020-2045 Regional Transportation Plan/Sustainable Communities Strategy (2020 -2045 RTP/SCS). The SCAQMD has established project-level significance thresholds which are used to assess regional and localized impacts of project -related criteria pollutant emissions. Non - exceedance of these thresholds is used to determine consistency with the AQMP. According to the AQMP, the principal contributor to air quality challenges in the air basin is mobile source emissions.

The project’s maximum daily emissions of criteria air pollutants during construction w ere estimated using the California Emissions Estimator Model (CalEEMod) version 2011.1. Projects in the SCAQMD with daily emissions that exceed any of the following emission thresholds may be considered significant for purposes of an evaluation under CEQA.

Table 3
SCAQMD CEQA Daily Emissions Thresholds
Pollutant Construction Operations
Reactive Organic Gasses (ROG) 75 55
Oxides of Nitrogen (NOX) 100 55
Carbon Monoxide (CO) 550 550
Particulate Matter (PM-10) 150 150
Particulate Matter (PM-2.5) 55 55
Sulphur Oxides (SOX) 150 150
Source: SCAQMD CEQA Air Quality Significance Thresholds. Revision March 2023.

Construction activity emissions are modeled based on the size of the project site, the amount and character of demolition activities , the estimated soil excavation and export, and construction of

4 LSA, Air Quality and Greenhouse Gas Emissions Impact Analysis Memorandum for the proposed Promenade Flats Project in Santa Clarita, California, August 23, 2023
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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

site features. The following table summarizes the project’s maximum daily emissions estimated by CalEEMod for short-term construction.

Table 4
Maximum Daily Construction Emissions (pounds/day)
Daily Emissions VOC NOX CO SO2 PM-10 PM-2.5
Construction1
Max. Daily Construction Emissions 3 19 18 <1 4 2
SCAQMD Thresholds 75 100 550 150 150 55
Significant Impact? Y/N No No No No No No
Source: Air Quality and Greenhouse Gas Emissions Impact Analysis Memorandum, Attachment C 1 Construction emissions reflect required compliance with fugitive dust control per SCAQMD Rule 403.

As shown in the table, the project would not exceed SCAQMD significance thresholds for air quality impacts.

Localized Significance Thresholds (LSTs) were developed to evaluate ambient air quality on a local level in addition to the more regional emissions -based thresholds of significance. The LST methodology addresses specific emissions, namely oxides of nitrogen (NOx), carbon monoxide (CO), and particulate matter (PM -10 and PM-2.5). LSTs represent the maximum emissions from a project that are not expected to cause or contribute to an exceedance of the most stringent applicable federal or state ambient air quality standard, and they are developed based on the ambient concentrations of that pollutant for each source receptor area and distance to the nearest sensitive receptor. Sensitive receptors are populations with the greatest sensitivity to air pollution exposure and include elderly, young children, the acutely and chronically ill, and persons engaged in strenuous work or exercise. The closest sensitive receptors that could potentially be subject to localized air quality impacts associated with construction of the proposed project would be the residences to the west, because they may be occupied for extended periods, and residents may be outdoors when exposure is highest.

This evaluation is based on maximum daily onsite construction emissions that would occur during any phase of project construction. Daily averages would be lower than the reported maximum amounts. Table 5, Project Construction Related LST Evaluation below shows the relevant threshold and the estimated peak daily onsite emissions during the construction phases that would generate the highest level of onsite emissions for each pollutant evaluated for LST impacts.

As shown in the table, the project’s maximum daily onsite construction emissions would not exceed the relevant LST screening table thresholds for LST -related criteria pollutants, and impacts would be less than significant.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Table 5
Project Construction Related LST Evaluation
LST 1.2 acre/25 meters Project Construction LST Emissions (pounds/day) NOx CO PM-10 PM-2.5
Peak Onsite Daily Emissions 16 16 1 1
LST Threshold 124 647 4 3
Significant Impact? Yes/No No No No No
Source: LSA Air Quality and Greenhouse Gas Emissions Impact Analysis Memorandum, Attachment C LST variables: Santa Clarita Valley, 1.2 acre, 25 meter receptor distance Construction emissions reflect required compliance with fugitive dust control per SCAQMD Rule 403.

Operational air quality impacts were assessed and the results are presented in Table 6, Maximum Daily Operations Emissions (pounds/day).

Table 6
Maximum Daily Operations Emissions (pounds/day)

As shown above, project operations would not result in the violation of any SCAQMD thresholds and there would be no significant impacts.

Odors
During construction h eavy‐duty equipment use would emit odors, however, construction‐ produced odors would be intermittent and cease to occur after each workday and once construction is completed. No other sources of objectionable odors would be present during construction. During operations the project would not be expected to produce objectionable odors as the use, residential units and a commercial component are not the type of use that results in the production of significant odor impacts such as oil refineries, agricultural use, or some industrial uses. Odor impacts would be less than significant.

Potential greenhouse gas impacts were also assessed in the LSA study but are not presented here as they are not considered in the evaluation of a Categorical Exemption. The study found no significant impacts according to analysis that is not applicable to the project’s Class 32 exemption.

Emissions Sources VOC NOX CO SO2 PM-10 PM-2.5
Area 1 <1 2 <1 <1 <1
Energy <1 <1 <1 <1 <1 <1
Mobile 2 1 15 <1 3 <1
Total 3 0.16 17 <0.00 3 <1
SCAQMD Thresholds 55 55 550 150 150 55
Significant Impact? Y/N No No No No No No
Source: LSA Air Quality and Greenhouse Gas Emissions Impact Analysis Memorandum, Attachment C November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Water Quality Effects
The proposed project would add a structure and landscaping to a site that is currently covered by impervious surfaces and would add an impervious surface to a lot that is currently undeveloped.

This w ill not result in significant effects to water quality either during construction or post - construction. According to Section 10.04.070 of the Santa Clarita Municipal Code the project must produce a Stormwater Pollution Prevention Plan (SWPPP) prior to issuance of grading or building permits. The plan must demonstrate which Best Management Practices (BMPs) are to be employed to retain sediments from areas disturbed by construction; retain construction -related materials, wastes, spills, or residues; contain runoff from equipment and vehicle washing; and control any potential erosion. The project will be required to submit a SWPPP, to demonstrate code compliance to the satisfaction of the City prior to final plan approval. Compliance with these regulations would ensure no significantly impacts to water quality during construction.

A hydrology report from CRC Enterprises
5 evaluated the existing conditions of the site, the
proposed conditions, and the proposed stormwater system and determined the project meets the requirements of the Los Angeles County Department of Public Works LID Manual. The proposed building is not adding any new impervious surfaces to the site, as the site is currently paved. As such, runoff from the new building will be routed into the existing drainage network as the system adequately handles the required 50 -year storm event threshold (0.95 inches). The new parking lot adds new impervious area to the site and as such adds an underground infiltration trench within the confines of the new lot to capture stormwater from a 0.95 inch rain event within its drainage area. The report determines the overall drainage design of the site is adequately designed to handle runoff from a 50-year storm event, and is consistent with the requirements of the County of Los Angeles, Department of Public Works. T herefore, operation of the project would not result in significant impacts to water quality.

E. The site can be adequately served by all required utilities and public services.

The project site is located within an existing shopping center surrounded by commercial buildings to the north, south, and east, and a multifamily residential complex to the west. All necessary utilities are present and serving the shopping center or existing apartment complex and will be available for the new development. Water and sewer capacity is available for the project. As stated in the SCV Water 20 20 Urban Water Management Plan existing and planned water supplies are adequate to meet demand during normal, single and multiple -dry year periods through 2050 within the SCV Water service area, based upon their growth assumptions. Project sewage will be treated at the Saugus Water Reclamation Plant which has a design capacity of 6.5 million gallons of wastewater per day (MGD) and is currently processing 5.2 MGD, and therefore has capacity to serve the project.
6 5
Hydrology Report, 2611-26135 Bouquet Canyon Road, CRC Enterprises, April 18, 2023 6 5.2 MGD estimate from email correspondence with Basil Hewitt, Public Information Supervisor with Los Angeles County Sanitation District on June 28, 2023.

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Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

A small mixed -use residential building would not require an expansion of any necessary public services, such as police, fire, or garbage collection, all of which currently serve the site and area.

Therefore, the site can be adequately served by required utilities and public services.

III. CONSIDERATION OF EXCEPTIONS
Section 15300.2 of the CEQA Statutes and Guidelines provides a list of exceptions for consideration of a project as categorically exempt. As listed in the City’s Class 32 Requirements, those exceptions relevant to the Class 32 Categorical Exemption, and justification that none of the Exceptions would apply to the proposed project are discussed below:

A. Cumulative Impact – The project and successive projects of the same type in the same place would not result in cumulative impacts.

The project would be constructed within an urbanized area of the City on a previously developed site, consistent with the General Plan land use designation and zoning , and consistent with the land use assumptions that underlie the Southern California Association of Governments (SCAG) 2020-2045 Regional Transportation Plan/Sustainable Communities Strategy , the regional document certified by CARB to meet the State’s 2035 GHG reduction targets. The project therefore falls within anticipated growth rates for the City and region. In the 6 th cycle Regional
Housing Needs Allocation Santa Clarita has been allocated 10,031 housing units for which it must identify suitable sites to accommodate that amount of new housing. The project provides 30 housing units toward th e allocation and projects of the same type in the same area would add more. As infill redevelopment the project is providing new housing and commercial space in the most efficient and environmentally benign manner possible. As such, the project and others of its type would contribute to the required housing needs of the City in an efficient manner and would not be anticipated to result in cumulative impacts.

B. Unusual Circumstances – There are no unusual circumstances that would create a reasonable possibility of significant effects.

The project site is already developed, as are the parcels surrounding it, and the existing shopping center and apartments have been in operation for decades. There is nothing unusual about the project site or setting with the exception of the south fork of the Santa Clara River west of the project site. This is unusual only in that it is not typical. All of the development in the immediate area is in proximity to the south fork or the main channel, and as far as the project is concerned, as infill redevelopment surrounded by development that is near the south fork, it is not an unusual circumstance of concern. Regardless, the presence of the south fork nearby is not an unusual circumstance that could reasonably be argued to result in the project creating a significant impact.

C. Scenic Highways – The project would not result in damage to scenic resources, including, but not limited to, trees, historic buildings, rock outcroppings, or similar resources, within an officially designated scenic highway.

The closest potential State Scenic Highway to the project site is a portion of Interstate 5 that is eligible for designation, beginning where it intersects Highway 14 and ending where it intersects November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Highway 126. The project site is not near or visible from the interstate and would not result in damage to any scenic resources associated with it.

D. Hazardous Waste Sites – The project is not located on a site that the Department of Toxic Substances Control and the Secretary of the Environmental Protection have identified, pursuant to Government Code section 65962.5, as being affected by hazardous wastes or clean-up problems.

The Department of Toxic Substance Control (DTSC) EnviroStor database 7 indicates there are no
existing or past hazardous waste facilities or cleanup sites within 1,000 feet of the project site.

The State Water Resources Control Board’s GeoTracker 8 database indicates that the United Oil gas station located at 26015 Bouquet Canyon Road is the site of a former LUST (leaking underground storage tank) cleanup. A leak was detected in 1986 and a vapor extraction well was installed in 1987. The site underwent soil vapor extraction from 1989 to 1991. The USTs present at the site were all removed and replaced in 1999. The case was closed in 2006 when there were no detectable traces of pollutants in nearby monitoring wells.

The project site itself is not associated with any record in the Cortese List (the resource list compiled pursuant to Government Code section 65962.5), as indicated via the EnviroStor database and the State Water Resources Control Board’s GeoTracker database. The United Oil station is not close enough to the project site to have been affected by it, and the case has been closed at the satisfaction of the DTSC. Therefore, the project is not located on a site that the Department of Toxic Substances Control and the Secretary of the Environmental Protection have identified, pursuant to Government Code section 65962.5, as being affected by hazardous wastes or clean-up problems.

E. Historical Resources – The project would not cause a substantial adverse change in the significance of an historical resource.

Neither the project site nor any properties in the immediate vicinity of the project site have been designated as historic resource s or identified as a potential historic resources in the Cultural and Historical Resources section of the Conservation and Open Space element of the General Plan, or the Historic Preservation Survey & Planning Analysis from August 2009. There are no structures on the site , construction of the project would not require demolition or modification of any structures, and none of the adjacent structures are identified as potential historic resources nor would they be eligible as such as all were constructed in or after 1987, therefore, the project would not cause a substantial adverse change in the significance of an historical resource.

7 Department of Toxic Substances Control, EnviroStor, Accessed June 22, 2023 at:
https://www.envirostor.dtsc.ca.gov/public/map/.
8 State Water Resources Control Board, GeoTracker, Accessed June 22, 2023 at:
https://geotracker.waterboards.ca.gov/map/?CMD=runreport&myaddress=26111+bouquet+canyon+rd.

November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

IV. CONCLUSION
Based on the above information and attached documentation, this analysis shows t hat development of the proposed Canyon Countr y Energy Storage project would be consistent with the criteria for a Class 32 Categorical Exemption per CEQA Statute Section 15332.

Attachments:

Attachment A – Transportation Memorandum
Attachment B – Noise Study
Attachment C – Air Quality Study
Attachment D – Hydrology Report

November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Attachment A
Transportation Memorandum

CARLSBAD
CLOVIS
IRVINE
LOS ANGELES
PALM SPRINGS
POINT RICHMOND

RIVERSIDE

ROSEVILLE
SAN LUIS OBISPO
20 Executive Park, Suite 200, Irvine, California  92614     949.553.0666     www.lsa.net

MEMORANDUM
DATE:  April 28, 2022
TO:  Robert Neman, Harvard 826 Property LLC, Manager
FROM:  Dean Arizabal, LSA, Principal
SUBJECT:  Transportation Memorandum for the Santa Clarita Plaza Project (LSA Project No. HAV2001)
The purpose of this transportation memorandum is to describe and document potential transportation impacts associated with the implementation of the proposed Santa Clarita Plaza Project (project). This technical information is provided for project review under the California Environmental Quality Act (CEQA).

PROJECT DESCRIPTION
Harvard 826 Property LLC is proposing to construct 30 multifamily residential units (inclusive of four live/work units), 7,266.1 square feet (sf) of first‐floor retail space, and a 3,027.4 sf rooftop yoga studio in a four‐story building at 26135 Bouquet Canyon Road in Santa Clarita (Figures 1 and 2; all figures are in Attachment
A). The approximately 1.2‐acre project site is located along the west side of Bouquet Canyon Road, north of Magic Mountain Parkway and south of Cinema Drive (Assessor’s Parcel No. 2811‐003‐018) in the community of Valencia. Access to the project site will be provided via an existing full‐ access driveway on Bouquet Canyon Road.

TRANSPORTATION ANALYSIS
This section includes an analysis of the project’s impacts to the transportation system based on the significance thresholds in Appendix G of the State CEQA Guidelines and provides a thorough justification for the conclusions provided herein.

Regulatory Setting
The following is a summary of State, regional, and local regulations that apply to transportation and circulation within the project study area.

State
Senate Bill 743. On September 27, 2013, Governor Jerry Brown signed Senate Bill (SB) 743 into law and codified a process that revises the approach to determining transportation impacts and mitiga
tion measures under CEQA. SB 743 directed the Governor’s Office of Planning and Research (OPR) to administer new CEQA guidance for jurisdictions by replacing the focus on automobile vehicle delay and level of service (LOS) or other similar measures of vehicular capacity or traffic

4/28/22 «P:\HAV2001\Traffic\Transportation Memo2.docx»
2 congestion in the transportation impact analysis with vehicle miles traveled (VMT). This change shifts the focus of the transportation impact analysis from measuring impacts to drivers, such as the amount of delay and LOS at an intersection, to measuring the impact of driving on the local, regional, and statewide circulation system and the environ ment. This shift in focus is expected to better align the transportation impact analysis with the statewide goals related to reducing greenhouse gas emissions, encouraging infill development, and promoting public health through active transportation. As a result of SB 743, the California Office of Administrative Law cleared the revised State CEQA Guideli
nes on December 28, 2018, with a statewide implementation date of July 1, 2020. The OPR Technical Advisory on Evaluating Transportation Impacts in CEQA (OPR Technical Advisory)1 provides a resource for agencies to use at their discretion.

Regional
Southern California Association of Governments. The Southern California Association of Governments (SCAG) is an association of county and city governments to address regional transportation issues. Its members include six counties (Imperial, Los Angeles, Orange, Riverside, San Bernardino, and Ventura) and 191 cities in an area covering more than 38 ,000 square miles. As the federally designated Metropolitan Planning Organization and the State‐designated Regional Transportation Planning Agency, SCAG is responsible for developing long‐range regional transportation plans, including sustainable communities strategy and growth forecast components, regional transportation improvement programs, regional housing needs allocations, and a portion of the South Coast Air Quality
Management District plans.

Local
City of Santa Clarita. The project is located in Santa Clarita. As such, the Circulation Element of the City of Santa Clarita General Plan2 and Transportation Analysis Updates in Santa Clarita3 are the guidance documents for the City of Santa Clarita (City) transportation system. These guidelines are intended to ensure that the traffic impacts of a development proposal on the existing and/or planned major street system are adequately addressed. Transportation Analysis Updates in Santa Clarita states that intersections where a project would add 50 or more net new trips durin g the a.m. and p.m. peak hours should be included in a Local Transportation Assessment (LTA).4

1   Governor’s Office of Planning and Research. 2018. Technical Advisory on Evaluating Transportation Impacts in CEQA. December. p. 12.
2   City of Santa Clarita. 2011. Circulation Element. City of Santa Clarita General Plan. June. Website:
https://www.codepublishing.com/CA/SantaClarita/html/SantaClaritaGP/4%20‐%20Circulation%20 Element.pdf (accessed December 2020).
3   City of Santa Clarita. 2020. Transportation Analysis Updates in Santa Clarita. May. Website: https://santa‐ clarita.com/Home/ShowDocument?id=18536 (accessed December 2020). 4   Ibid.

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3 Environmental Setting
Existing Circulation System
Bouquet Canyon Road is a five‐lane, north‐south roadway (three northbound lanes and three southbound lanes) along the project frontage. Bouquet Canyon Road is classified as a Major Highway in the Circulation Element of the City of Santa Clarita General Plan.1 A sidewalk is provided on the west side of the street. On‐street parking is permitted in select locations on the west side of the street.

Impact Analysis
a. 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. In order to assess the impact of the project on the surrounding circulation system, vehicle trips were generated for temporary construction activities based on the anticipated nu
mber of workers and trucks, as well as for typical operations of the project.

Construction of the project is anticipated to take approximately 66 weeks and will include the following five phases (daily worker and truck estimates and phase durations):
 Phase 1: Site Preparation (8 workers per day for 1 week)  Pha
se 2: Grading (10 workers per day for 1 week)
 Phase 3: Building Construction (32 workers and 7 vendor trucks per day for 58 weeks)  Phase 4: Paving (15 workers per day for 3 weeks)
 Phase 5: Architectural Coating (6 workers per day for 3 weeks) It is assumed that workers would arrive at the site in the a.m. peak hour and dep art the site during
the p.m. peak hour. Truck trips are anticipated to occur throughout the day. A passenger car equivalent (PCE) factor of 2.0 has been applied to the trucks.

Tables A and B (all tables provid ed in Attachment B) present the construction and operational trip generation for the project.

As shown in Table A, Phase 3 (Building Construction) is the period of construction with the highest trip generation. Over approximately 58 weeks, Phase 3 is anticipated to generate 92 average daily trips (ADT), i
ncluding 36 trips (34 inbound and 2 outbound) in the a.m. peak hour and 36 trips (2 inbound and 34 outbound) in the p.m. peak hour, in PCEs. All other construction phases would generate 30 or fewer ADT, including 15 or fewer peak‐hour trips, in PCEs.

1   City of Santa Clarita. 2011. Circulation Element. City of Santa Clarita General Plan. June. Website:
https://www.codepublishing.com/CA/SantaClarita/html/SantaClaritaGP/4%20‐%20Circulation%20 Element.pdf (accessed December 2020).

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4 The Institute of Transportation Engineers (ITE) Trip Generation Manual, 11th Edition,1 is a nationally recognized source for estimating site‐specific trip generation. The ITE trip rates for Land Use Code 221 (Multifamily Housing [Mid‐Rise]), Land Use Code 822 (Strip Retail Plaza), and Land Use Code 492 (Health/Fitness Club) were applied to the project uses. As shown on Table B, the project has the potential to gene
rate 636 ADT, including 32 trips (15 inbound and 17 outbound) in the a.m. peak hour and 70 trips (37 inbound and 33 outbound) in the p.m. peak hour.

The project would generate a maximum of 36 peak‐hour trips for any period of construction and a maximum
of 32 a.m. and 70 p.m. peak‐hour trips once the project is operational. According to Transportation Analysis Updates in Santa Clarita, intersections where a project would add 50 or more net new trips during the a.m. and p.m. peak hours should be included in an LTA.2 The project would not generate 50 or more trips during both peak hours, and the project would not contribute 50 or more peak‐hour trips to any surrounding intersections. As such, the project is not anticipated to result in any LOS or operational deficiencies to the surrounding circulation system based on its low number of trips for temporary cons
truction and typical operations.

The project would not make any changes to the public right‐of way in the project vicinity or generate a substantial number of daily or peak‐hour vehicle trips for construction or typical operations to warrant modifications to any transportation facili ties (e.g., vehicular, transit, bicycle, or pedestrian). The project would not preclude alternative modes of transportation or facilities (e.g., transit, bicycle, or pedestrian). Therefore, the project would not conflict with the Circulation Element of the City of Santa Clarita General Plan. No mitigation is required. b. Would the project conflict or be inc onsistent with CEQA Guidelines Section 15064.3, Subdivision (b)?
Less Than Significant Impact. State CEQA Guidelines Section 15064.3, subdivision (b), states that transportation impacts for land use projects are to be measured by evaluating the project’s VMT or the amount and distance of automobile travel attributable to the project, as outlined in the following:

Vehicle miles traveled exce
eding an applicable threshold of significance may indicate a significant impact. Generally, projects within one‐half mile of either an existing major transit stop or a stop along an existing high‐quality transit corridor should be presumed to cause a less than significant t ransportation  impact.

The OPR Technical Advisory and Transportation Analysis Updates in Santa Clarita both provide guidance for screening land use projects from a detailed VMT analysis and the presumption of a less than significant transportation impact, such as project size, locally serving retail use, and project located in a low VMT area.

1   Institute of Transportation Engineers. 2021. Trip Generation Manual. 11th ed. 2   City of Santa Clarita. 2020. Transportation Analysis Updates in Santa Clarita. May. Website: https://santa‐ clarita.com/Home/ShowDocument?id=18536 (accessed December 2020).

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5 Transportation Analysis Updates in Santa Clarita recommends that locally serving retail uses (less than 50,000 sf) and residential uses located in a low VMT area (a City‐identified area that is already 15 percent below the baseline VMT) are screened from a VMT analysis.1 The project includes 10,293.5 sf of locally serving retail use (7,2661 sf of first‐floor retail space and a 3,027.4 sf yoga studio) and is located in a low VMT area (as shown in Figure 5 of Transportation Analysis Updates in Santa Clarita [provided in Attachment C]). Because the project meets the City’s VMT screenin
g criteria, it is not subject to a VMT analysis and is presumed to have a less than significant transportation impact.

As such, the proposed would not conflict or be inconsistent with State CEQA Guidelines Section 15064.3(b). Potential impacts would be less than significant, and no mitigation is required. c. Would the project s
ubstantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? Less Than Significant Impact. Regional access to the project is provided by Bouquet Canyon Road.

Site access is provided via an existing full‐access driveway on Bouquet Canyon Road. A ccess would not change as part of the project. As such, the project would not substantially increase hazards for vehicles due to a geometric design feature or incompatible uses, and impacts would be less than significant. No mitigation is required.
d. Would the project result in inadequate eme rgency access? Less Than Significant Impact. Site access would not change as part of the project and would continue to be provided from a full‐access driveway on Bouquet Canyon Road. Since the project would not modify the existing configuration of the driveway along Bouquet Canyon Road, emergency access to the si te would not be affected. Therefore, impacts associated with emergency access would be less than significant. No mitigation is required.

Attachments:  A: Figures 1 and 2
B:  Tables A and B
C:  Figure 5 of Transportation Analysis Updates in Santa Clarita

1   City of Santa Clarita. 2020. Transportation Analysis Updates in Santa Clarita. May. Website: https://santa‐ clarita.com/Home/ShowDocument?id=18536 (accessed December 2020).

T RANSPORTATION   M EMORANDUM
A PRIL   2022
S ANTA   C LARITA   P LAZA   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Traffic\Transportation Memo2.docx «04/28/22» ATTACHMENT A

FIGURES 1 AND 2
SOURCE: ArcGIS Online Topographic Map (2020)
Ven tu ra
County
Los
Angeles
County
27 170
126
14 118
405
210
5 I:\HAV2001\G\Project_LocaƟon.ai (6/1/2021)
FIGURE 1
Santa Clarita Plaza
Project LocaƟon
Project Vicinity
FEET
LEGEND
Project Site
0 500 1000
Project Location

BUILDING DATA

SANTA CLARITA PLAZA APARTMENTS

L E G E N D
[E] IHOP
23 22 21 20 19 18 17 16 15 14
12 11 10 9 8765 4 3 2 113
24 27
28 29
30 OPEN
SPACE
12 11
10 9
8 7
6 5
4 3
2 1
13 31
32 33
34 36
37 35
38 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112
134
135 136 137 138 139 140 141 142 143 144 145 146 147 148 131
130
landscaping landscaping
NEW PARKING AREAlandscaping
74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 189
192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209
149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 75 77
78 76
79 80
82 83
81 84
85 86
91 93
92 94
96 95
97 99
98 100
102
101
103
105
104
106
108
107
109
111
110
87 89
88 90
230
228
227
229
226
225
224
223
222
231
233
234
232
235
237
238
236
221
220
219
218
216
215
214
213
212
211
210
6 8
9 10
11 12

TRANSFORMER

OPEN SPACE

SEPARATED FROM

PARKING BY A WALL
42" HIGH

LANDSCAPE PLANTER
AT THREE (3) FEET IN
WIDTH
SIX (6) FOOT HIGH

MASONRY WALLS
SIX (6) FOOT HIGH

MASONRY WALLS
20' MAX. BETWEEN

TREES, BETWEEN

RESIDENTIAL AND

COMMERCIAL

PATH OF TRAVELPATH OF TRAVEL

LOADING SPACE
IHOP
13 12 11 10 9 8 7 6 54 32 125 26
1 2 3
4 5
39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
7 PATH OF TRAVEL
EXIT

EXIT EXIT EXIT EXIT EXIT
EXIT
EXIT
ENTR
EXIT

ENTR ENTR ENTR
ENTR
ENTR
ENTR
ENTR

PATH OF TRAVEL PATH OF TRAVEL PATH OF TRAVEL

PATH OF TRAVEL

PATH OF TRAVEL
129 128
133
132
187 188
190 191
239

VAN ACCESIBLE
EVCS

STANDARD

ACCESIBLE
EVCS

NOT PART

OF THE PROJECT
SOURCE: CHARC Design
FEET
60300
FIGURE 2
I:\HAV2001\G\Site_Plan.ai (6/1/2021)
Santa Clarita Plaza
Site Plan
LEGEND
Project Site
T RANSPORTATION   M EMORANDUM
A PRIL   2022
S ANTA   C LARITA   P LAZA   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Traffic\Transportation Memo2.docx «04/28/22» ATTACHMENT B

TABLES A AND B
Duration1
Description No. Type PCE ADT In Out Total In Out Total
Site

1. Preparation 1 week Workers 2
8 Passenger 1 16 8 0 8 0 8 8

2. Grading 1  week Workers 2
10 Passenger 1 20 10 0 10 0 10 10
Workers 2
32 Passenger 1 64 32 0 32 0 32 32
Building Vendor Trucks 2
7 Truck 2 28 2 2 4 2 2 4

3. Construction 58  weeks Total 92 34 2 36 2 34 36

4. Paving 3 weeks Workers 2
15 Passenger 1 30 15 0 15 0 15 15
Architectural

5. Coating 3  weeks Workers 2
6 Passenger 1 12 6 0 6 0 6 6
1 Construction is anticipated to occur from August 2022 to December 2023. 2 Workers are assumed to arrive during the a.m. peak hour and depart during the p.m. peak hour.

Truck trips are assumed to occur throughout the day.

ADT = average daily trips
PCE = passenger car equivalent. A worker vehicle has a PCE of 1 and a truck has a PCE of 2.

PM Peak Hour
Description
Table A: Construction Trip Generation
Construction Phase Daily Vehicles AM Peak Hour
P:\HAV2001\Traffic\xls\trip generation.xlsx\Construction_Apr 2022 (4/28/2022) In Out Total In Out   Total
Multifamily Mid‐Rise du 4.54 0.09 0.28 0.37 0.24 0.15 0.39 Retail TSF 54.45 1.42 0.94 2.36 3.30 3.29 6.59
Health/Fitness Club TSF 34.50 0.67 0.64 1.31 1.97 1.48 3.45 Multifamily Mid‐Rise 30 du 136 3 8 11 7 5 12
Retail 7.2661 TSF 396 10 7 17 24 24 48
Health/Fitness Club 3.0274 TSF 104 22464 1 0
Total 636 15 17 32 37 33 70
1 Trip rates from the Institute of Transportation Engineers (ITE) Trip Generation Manual,  11th Edition (2021).

Land Use Code 221 ‐ Multifamily Housing (Mid‐Rise) ‐ Between 4 and 10 Levels Land Use Code 822‐ Strip Retail Plaza ‐ Less than 40 TSF of Gross Leasable Area Land Use Code 492 ‐ Health/Fitness Club
ADT = average daily trips
du = dwelling unit
TSF = thousand square feet
Trip Rates1
Project Trip Generation
Table B: Project Trip Generation
Land Use Size Unit ADT
AM Peak Hour PM Peak Hour
P:\HAV2001\Traffic\xls\trip generation.xlsx\ITE 11th (4/25/2022) T RANSPORTATION   M EMORANDUM
A PRIL   2022
S ANTA   C LARITA   P LAZA   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Traffic\Transportation Memo2.docx «04/28/22» ATTACHMENT C

FIGURE 5 OF TRANSPORTATION ANALYSIS UPDATES IN SANTA CLARITA

/0 /1 /2 /3 /1 /i255 /5 /6 /1 /7 /8 /3 /1
/9/10/10 /11 /6 /1 /2 /11 /12 /i255 /13 /1 /7 /14
/15 /2 /16 /17 /6 /17 /12 /i255/18/19
/20/21/22/23/24/23/20/24
/25/22/26/21/27/28/29/30
/31/27/28/32/33/27/28/34/23/28/35/23/27/32
/31/23/36/21/32/27/32/33/27/28/34/23/28/35/32
/37/38/21/39/36/32/35/23/27/32
/29/36/27/22/21/24/40/41/27/33/27/28/34/23/28/35/23/27/32 /39/36/40/42/21/43/40/21/30
/20/24
/44/40/36/21/34/33/27/28/34/23/28/35/32
/45/23/23/41/38/40/36/36/46/36
/47 /42 /21 /28 /48 /21 /i255 /31 /22 /23 /41 /41
/33 /27 /36 /50 /24 /23 /42 /21 /i255 /46 /36
/33 /23/51/51/21/24 /22 /21 /i255 /33 /21 /28 /41 /21 /24 /i255 /20 /24 /52/34/23/28/53/47/42
/54/21/30/38/27/36/36/47/42
/25/27
/50 /40 /22 /i255
/25/23
/48 /28 /41 /27 /40 /28 /i255 /29 /30
/31/23/36/21/32/27/32/33/27/28/34/23/28/35/23/27/32
/43 /40 /27 /i255 /29 /24 /40 /28 /22 /21 /53 /53 /27
/55/53/22/23/28/32/40/32/23/33/27/28/34/23/28/35/23/27/32 /31/40/21/24/24/27/56/30
/54/21/30/38/27/36/36/35/27/28/22/38/35/32
/33/23/57/57/21/24/56/40/36/36/20/24/40/42/21
/31/40/21/24/24/27/56/40/50/38/30/27/34
/29/23/21/29/30
/47/50/48/27/20/48/36/22/21/33/27/28/34/23/28/35/23/27/32 /25/27/40 /28 /i255 /31 /41
/47 /36 /41 /27 /i255 /43 /40 /53 /41 /27 /i255 /47 /42/37/38/21/39/36/32/35/32 /58 /23 /36 /32 /21 /28 /i255 /43 /27 /36 /36 /21 /34 /i255 /35 /32 /31/21/22/23/33/27/28/34/23/28/35/23/27/32
/25/27
/36 /36 /23 /24 /34 /i255 /20 /24
/20 /27 /42 /21 /28 /57 /23 /24 /41 /i255 /35 /23 /27 /32 /44/21
/53 /41 /24 /40 /32 /50 /21 /i255 /29 /30
/33 /27 /28 /34 /23 /28 /i255 /29 /27 /24 /59 /i255 /46 /36 /31/51/34
/41 /38 /i255 /20 /24
/44/38/40 /41 /21 /53 /i255 /33 /27 /28 /34 /23 /28 /i255 /35 /32 /37/38/21/39/36/32/35/32
/29 /36 /48
/51/i255
/33 /27 /28 /34 /23 /28 /i255 /35 /32
/37 /21 /53 /23 /24 /23 /i255 /20 /21 /36 /i255 /43 /27 /36 /36 /21 /i255 /20 /24 /45/24/27/28/59/36/40/28/29/30/52/27/59/21/56/48/50/38/21/53/35/32 /35 /27 /40 /36 /24 /23 /27 /32 /i255 /47 /42
/58 /23 /36 /32 /21 /28 /i255 /37 /24 /40 /27 /28 /50 /36 /21 /i255 /35 /32 /33 /38 /40 /60 /48 /40 /41 /23 /i255 /33 /27 /28 /34 /23 /28 /i255 /35 /23 /27 /32 /56/40/36/36/22/24/21/53/41/29/27/24/59/30/27/34
/31/27/28/45/24/27/28/22 /40/53/60/48/40/41/23/33/27/28/34/23/28/35/23/27/32 /56/27/53/36/21/34/33/27/28/34/23/28/35/23/27/32
/43/27/53/60/48/21/61/33/27/28/34/23/28/35/23/27/32
/46/23/48/60/48/21/41/33/27/28/34/23/28/35/23/27 /32
/52/40/41/41/36/21/37/48/62/48/28/50/27/33/27/28/34/23/28/35/23/27/32 /63 /64 /65
/63 /66
/67
/68 /69 /70 /71 /69 /i255 /73 /74 /69 /75 /76 /71 /69
/77 /78 /79 /80 /81 /79 /78 /i255 /81 /83 /80 /84 /i255 /85 /86/87/i255/88 /79 /89 /90 /91 /i255 /92 /93 /81 /94 /i255 /95 /80 /96 /79 /89 /93 /84 /79 /95 /79 /81 /91 /79 /79 /84 /i255 /85 /86/87/i255/88 /79 /89 /90 /91 /i255 /92 /93 /81 /94 /i255 /95 /80 /96 /79 /89 /93 /84 /79 /i255 /80 /84 /97 /i255 /92 /93 /81 /94 /i255 /95 /80 /96 /79 /89 /93 /84 /79 /i255 /99 /88 /90 /100 /79 /i255 /73 /76 /71 /101 /i255 /102 /103 /104 /105 /106 /107 /108 /105 /109 /110 /111 /111 /i255 /71 /112 /69 /70 /i255 /113 /114 /i255 /115 /110 /111 /76 /116 /110 /70 /71 /111 /117 /118 /119 /120 /121 /122 /i255 /124
/125 /69 /76 /74 /101 /i255 /126 /127/128/110/129 /130 /69 /111 /110 /116 /i255 /131/132/133/i255 /134 /110 /75 /i255 /73 /69 /134 /76 /71 /69 /73 /127/128/134/69 /75 /110 /116 /i255 /71 /127 /i255 /73 /76 /71 /101 /i255 /135 /136 /110 /75 /69 /137 /110 /i255 /138 /139 /114 /139 /114 /140 The VMT metrics illustrated in Figure 5 can
be used to screen residential projects in low
VMT areas. Specifically, if a residential
project is proposed in a TAZ that has VMT at
least 15 percent lower than the citywide
average, the project would also be expected
to generate VMT at least 15 percent lower
than the citywide average.

Project Site (within a low VMT area of greater than 15% below City baseline) November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Attachment B
Noise Study

CARLSBAD
CLOVIS
IRVINE
LOS ANGELES
PALM SPRINGS
POINT RICHMOND

RIVERSIDE

ROSEVILLE
SAN LUIS OBISPO
3210 El Camino Real, Suite 100, Irvine, California  92602     949.553.0666     www.lsa.net

MEMORANDUM
DATE:  August 9, 2023
TO:  Robert Neman, Harvard 826 Property, LLC
FROM:  Jason Lui, Associate/Senior Noise Specialist
SUBJECT:  Noise and Vibration Impact Analysis Memorandum for the proposed Promenade Flats Project at 26135 Bouquet Canyon Road in Santa Clarita, California

INTRODUCTION
This noise and vibration impact analysis has been prepared to evaluate the potential noise and vibration impacts associated with the proposed Promenade Flats Project in Santa Clarita, California (project). This report is intended to satisfy the City of Santa Clarita (City) requirement and the California Environmental Quality Act (CEQA) for a project‐specific noise and vibration impact analysis by exam
ining the impacts of the proposed uses on the project site and determining whether reduction measures would be required to reduce noise and vibration impacts.

PROJECT LOCATION
The project site is located along the west side of Bouquet Canyon Road, north of Magic Mountain Parkway and south of Cinema Drive at 26135 Bouquet Canyon Road (Assessor’s Parcel Number 2811‐003‐018) in the community of Valencia. The project site has a Mixed Use Corridor (MXC) zoning designation. Figure 1, below, shows the project location.

PROJECT DESCRIPTION
The proposed project would remove a portion of the existing parking lot to accommodate a new four‐story, mixed‐use building on 1.2 acres. The proposed project would include a total of 15,741.50 square feet (ft) of commercial use consisting of a 7,266.10 sf first‐floor retail space, a 3,027.40 sf rooftop yoga studio, and the exi
sting 5,448 sf International House of Pancakes (IHOP) restaurant. In addition to the new commercial uses, the proposed building would include four live/work units and 26 one‐bedroom units on floors two through four. Additionally, a new 14,359 sf (0.33 acre) parking lot would be constructed on an adjacent vacant parcel to offset the parkin g that would be removed as part of the project. Construction of the proposed project would start in August 2022 and would be completed in approximately 16 months. Figure 2 shows the site plan. Figures 3 through 5 show the floor plans of the proposed mixed‐ use building.

SOURCE: ArcGIS Online Topographic Map (2020)
Ven tu ra
County
Los
Angeles
County
27 170
126
14 118
405
210
5 I:\HAV2001\G\Project_LocaƟon.ai (10/6/2023)
FIGURE 1
Promenade Flats
Project LocaƟon
Project Vicinity
FEET
LEGEND
Project Site
0 500 1000
Project Location

NOT PART

OF THE PROJECT
SOURCE: CHARC Design
FEET
60300
FIGURE 2
I:\HAV2001\G\Site_Plan.ai (10/6/2023)
Promenade Flats
Site Plan
LEGEND
Project Site
I:\HAV2001\G\Site_Plan_1st-2nd_Floor.ai (10/6/2023)
FIGURE 3
First and Second Floor Plan
Promenade Flats
UP
A
1 B C D E F G H I J K
2 3
4 5
6 7
8 9
10 11
12 13
14 15
EXIT
EXIT
EXIT
EXIT
EXIT
EXIT
EXIT

EXIT EXIT
EXIT
ENTR
ENTR
ENTR
ENTR
ENTR
ENTR
ENTR
ENTR
1 1
1 1
1 1
1 1
4 4
4 4
4 4
4 4
4 3
A
1 B C D E F G H I J K
2 3
4 5
6 7
8 9
10 11
12 13
14 15
7 8
8 8
9 10
11 CMSD
SD
G
7 8
8 11
SD
9 CMSD
G
8 8
8 9
10 11
CMSD
SD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
SD
7 8
8 11
SD
9 CMSD
SD
7 8
8 8
9 G
EXIT
4 CMSD
CMSD
SD
G
7 8
8 9
G
8 SD
G

IN FRONTOF LIFT
EXIT
4 CMSD
G
G
G
G
10 10
10 1
1ST FLOOR
2 2ND FLOOR

PROJECT
NORTH

PROJECT
NORTH
SOURCE: CHARC Design
FEET
50250
I:\HAV2001\G\Site_Plan_3rd-4th_Floor.ai (10/6/2023)
FIGURE 4
Third and Fourth Floor Plan
Promenade Flats
SOURCE: CHARC Design
FEET
50250
UP
A
1 B C D E F G H I J K
2 3
4 5
6 7
8 9
10 11
12 13
14 15
7 8
8 8
9 10
11 CMSD
SD
G
7 8
8 11
SD
9 CMSD
G
8 8
8 9
10 11
CMSD
SD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
SD
7 8
8 11
SD
9 CMSD
SD
7 8
8 8
9 G
EXIT
4 CMSD
CMSD
SD
G
7 8
8 9
G
8 SD
2 - HRS SHAFT
5'x5' CLRIN FRONTOF LIFT
G
2 - HRS SHAFT
5'x5' CLRIN FRONTOF LIFTIN FRONTOF LIFT
EXIT
4 CMSD
G
G
G
G
10 10
10 A
1 B C D E F G H I J K
2 3
4 5
6 7
8 9
10 11
12 13
14 15
7 8
8 8
9 10
11 CMSD
SD
G
7 8
8 11
SD
9 CMSD
G
8 8
8 9
10 11
CMSD
SD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
G
7 8
8 8
11 SD
9 CMSD
7 8
8 8
9 10
11 CMSD
SD
7 8
8 11
SD
9 CMSD
SD
7 8
8 8
9 G
EXIT
4 CMSD
CMSD
SD
G
7 8
8 9
G
8 SD
G
EXIT
4 CMSD
G
G
G
G
10 10
10 1
3RD FLOOR
2 4TH FLOOR

PROJECT
NORTH

PROJECT
NORTH
I:\HAV2001\G\Site_Plan_5th_Floor.ai (10/6/2023)
FIGURE 5
FiŌh Floor Plan
Promenade Flats
A
1 B C D E F G H I J K
2 3
4 5
6 7
8 9
10 11
12 13
14 15
7 EXIT
4 CMSD
EXIT
4 CMSD
1 5TH FLOOR

PROJECT
NORTH
SOURCE: CHARC Design
FEET
50250

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 7 CHARACTERISTICS OF SOUND
Sound is increasing to such disagreeable levels in the environment that it can threaten quality of life.

Noise is usually defined as unwanted sound. Noise consists of any sound that may produce physiological or psychological damage and/or interfere with communication, work, rest, recreation, and sleep.

To the human ear, sound has two significant characteristics: pi tch and loudness. Pitch is generally an annoyance, while loudness can affect the ability to hear. Pitch is the number of complete vibrations, or cycles per second, of a wave resulting in the tone’s range from high to low. Loudness is the strength of a sound that describes a noisy or quiet environment and is measur ed by the amplitude of the sound wave. Loudness is determined by the intensity of the sound waves combined with the reception characteristics of the human ear. Sound intensity refers to how hard the sound wave strikes an object, which in turn produces the sound’s effect. This characteristic of sound can be precisely measured with instruments. The analysis of a project defines the noise environment of the project area in terms of sound intensity and its effect on adjacent sensitive land uses.

Measurement of Sound
Sound intensity is measured through the A‐weighted scale to correct for the relative frequency response of the human ear. That is, an A‐weighted noise level de‐emphasizes low and very high frequencies of sound similar to the human ear’s de‐emphasis of these frequencies. Decibels, unlike the linear scale (e.g., inches or pounds), are measure d on a logarithmic scale, which is a scale based on powers of 10.

For example, 10 decibels (dB) is 10 times more intense than 0 dB, 20 dB is 100 times more intense than 0 dB, and 30 dB is 1,000 times more intense than 0 dB. Thirt y decibels (30 dB) represents 1,000 times as much acoustic energy as 0 dB. The decibel scale increases as the square of the change, representing the sound pressure energy. A sound as soft as human breathing is about 10 times greater than 0 dB. The decibel system of measuring so und gives a rough connection between the physical intensity of sound and its perceived loudness to the human ear. A 10 dB increase in sound level is perceived by the human ear as only a doubling of the loudness of the sound. Ambient sounds generally range from 30 dB (very quiet) to 100 dB (very loud).

Sound leve
ls are generated from a source, and their decibel level decreases as the distance from that source increases. Sound dissipates exponentially with distance from the noise source. For a single point source, sound levels decrease approximately 6 dB for each doubling of distance from the source. This drop‐
off rate is appropriate for noise generated by stationary equipment. If noise is produced by a line source (e.g., highway traffic or railroad operations), the sound decreases 3 dB for each doubling of distance in a hard‐site environment; however, line source noise in a relatively flat environment with absorptive vegetation decr
eases 4.5 dB for each doubling of distance.

There are many ways to rate noise for various time periods, but an appropriate rating of ambient noise affecting humans also accounts for the annoying effects of sound. The equivalent continuous sound level (Leq) is the total sound energy of time‐varying noise over a sample period. However, the predominant rating scales for human communities in the State of California are Leq and the Community Noise Equivalent Level (CNEL) or the day‐night average noise level (Ldn) based on A‐weighted decibels (dBA). CNEL is the time‐varying noise over a 24‐hour period, with a 5 dBA

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 8 weighting factor applied to the hourly Leq for noises occurring from 7:00 p.m. to 10:00 p.m. (defined as relaxation hours), and a 10 dBA weighting factor applied to noises occurring from 10:00 p.m. to 7:00 a.m. (defined as sleeping hours). Ldn is similar to the CNEL scale but without the adjustment for events occurring during relaxation hours. CNEL and Ldn are within 1 dBA of each other and are normally interchangeable. The City uses the CNEL noise scale for long‐term noise impact assessment.

Other noise rating scales of importance during assessment of the annoyance factor include the maximum noise level (Lmax), which is the highest exponential time‐averaged sound level that occurs during a stated time period. The noise environments discussed in this analysis for short‐term noise impacts are specified in terms of maximum levels denoted by Lmax, which reflects peak operating conditions and addresses the annoying aspects of intermittent noise. It is often used together with another noise scale, or noise standards in terms of percentile noise levels, in noise ordinances for enforcement purposes. For example, the L10 noise level represents the noise level exceeded 10 percent of the time during a stated period. The L50 noise level represents the median noise level.

Half the time the noise level exceeds this level, and half the time it is less than this level. The L90 noise level represents the noise level exceeded 90 percent of the time and is considered the background noise level during a monitoring period. For a relatively constant noise source, Leq and L50 are approximately the same.

Noise impacts can be described in three categories. The first category includes audible impacts, which refers to increases in noise levels noticeable to humans. Audible increases in noise levels generally refer to a change of 3 dB or greater because this level has been found to be barely perceptibl
e in exterior environments. The second category, potentially audible, refers to a change in the noise level between 1 dB and 3 dB. This range of noise levels has been found to be noticeable only in laboratory environments. The last category includes changes in noise levels of less than 1 dB, which are in
audible to the human ear. Only audible changes in existing ambient or background noise levels are considered potentially significant.

Physiological Effects of Noise
Physical damage to human hearing begins at prolonged exposure to noise levels higher than 85 dBA.

Exposure to high noise levels affects the entire system, with prolonged noise exposure in excess of 75 dBA increasing body tensions, thereby affecting blood pressure and functions of the heart and the nervous system. In comparison, extended period s of noise exposure above 90 dBA would result in permanent cell damage. When the noise level reaches 120 dBA, a tickling sensation occurs in the human ear, even with short‐term exposure. This level of noise is called the threshold of feeling. As the sound reaches 140 dBA, the tickling sensation  is replaced by the feeling of pain in the ear (the threshold of pain). A sound level of 160–165 dBA will result in dizziness or loss of equilibrium. The ambient or background noise problem is widespread and generally more concentrated in urban areas than in outlying, less developed area. Table A  lists definitions of acoustical terms, and Table B shows common sound levels and their sources.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 9 Table A: Definitions of Acoustical Terms
Term  Definitions
Decibel, dB  A unit of sound level that denotes the ratio between two quantities that are proportional to power; the number of decibels is 10 times the logarithm (to the base 10) of this ratio.

Frequency, Hz  Of a function periodic in time, the number of times that the quantity repeats itself in one second (i.e., the number of cycles per second).

A‐Weighted Sound
Level, dBA
The sound level obtained by use of A‐weighting. The A‐weighting filter de‐emphasizes the very low and very high frequency components of the sound in a manner similar to the frequency response of the human ear and correlates well with subjective reactions to noise. (All  sound levels in this report are A‐ weighted, unless reported otherwise.)
L01, L10, L50, L90  The fast A‐weighted noise levels that are equaled or exceeded by a fluctuating sound level 1%, 10%, 50%, and 90% of a stated time period, respectively.

Equivalent Continuous
Noise Level, Leq
The level of a steady sound that, in a stated time period and at a stated location, has the same A‐ weighted sound energy as the time varying sound.

Community Noise
Equivalent Level, CNEL
The 24‐hour A‐weighted average sound level from midnight to midnight, obtained after the addition of 5 dBA to sound levels occurring in the evening from 7:00 PM to 10:00 PM and after the addition of 10 dBA to sound levels occurring in the night between 10:0 0 PM and 7:00 AM.

Day/Night Noise Level,
Ldn
The 24‐hour A‐weighted average sound level from midnight to midnight, obtained after the addition of 10 dBA to sound levels occurring in the night between 10:00 PM and 7:00 AM.

Lmax, Lmin  The maximum and minimum A‐weighted sound levels measured on a sound level meter, during a designated time interval, using fast time averaging.

Ambient Noise Level  The all‐encompassing noise associated with a given environment at a specified time, usually a composite of sound from many sources from many directions, near and far; no particular sound is dominant.

Intrusive  The noise that intrudes over and above the existing ambient noise at a given location. The relative intrusiveness of a sound depends upon its amplitude, duration, frequency, and time of occurrence and tonal or informational content, as well as the prevailing ambient noise level.

Source: Handbook of Acoustical Measurements and Noise Control (Harris 1991).

Table B: Common Sound Levels and Their Noise Sources
Noise Source  A‐Weighted Sound
Level in Decibels  Noise Environments  Subjective Evaluations Near Jet Engine  140  Deafening  128 times as loud
Civil Defense Siren  130  Threshold of Pain  64 times as loud Hard Rock Band  120  Threshold of Feeling  32 times as loud Accelerating Motorcycle at a Few Feet Away  110  Very Loud  16 times as loud Pile Driver; Noisy Urban Street/Heavy City Traffic  100  Very Loud  8 times as loud Ambulance Siren; Food Blender  95  Very Loud  —
Garbage Disposal  90  Very Loud  4 times as loud
Freight Cars; Living Room Music  85  Loud  —
Pneumatic Drill; Vacuum Cleaner  80  Loud  2 times as loud Busy Restaurant  75  Moderately Loud  —
Near Freeway Auto Traffic  70  Moderately Loud  Reference level Average Office  60  Quiet  One‐half as loud
Suburban Street  55  Quiet  —
Light Traffic; Soft Radio Music in Apartment  50  Quiet  One‐quarter as loud Large Transformer  45  Quiet  —
Average Residence without Stereo Playing  40  Faint  One‐eighth as loud Soft Whisper  30  Faint  —
Rustling Leaves  20  Very Faint  —
Human Breathing  10  Very Faint  Threshold of Hearing
—   0  Very Faint  —
Source: Compiled by LSA Associates, Inc. (2015).

FUNDAMENTALS OF VIBRATION
Vibration refers to ground‐borne noise and perceptible motion. Ground‐borne vibration is almost exclusively a concern inside buildings and is rarely perceived as a problem outdoors. Outdoors, the

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 10 motion may be discernible, but without the effects associated with the shaking of a building, there is less adverse reaction. Vibration energy propagates from a source through intervening soil and rock layers to the foundations of nearby buildings. The vibration then propagates from the foundation throughout the remainder of the structure. Building vibration ma y be perceived by occupants as the motion of building surfaces, the rattling of items on shelves or hanging on walls, or a low‐frequency rumbling noise. The rumbling noise is caused by the vibration of walls, floors, and ceilings that radiate sound waves. Annoyance from vibration often occurs when the vibration excee ds the threshold of perception by 10 vibration velocity decibels (VdB) or less. This is an order of magnitude below the damage threshold for normal buildings.

Typical sources of ground‐borne vibration are construction activities (e.g., blasting, pile driving, and operating heavy‐duty earthmoving equipment), steel‐wheeled trai ns, and occasional traffic on rough roads. Ground‐borne vibration and noise from these sources are usually localized to areas within approximately 100 feet (ft) from the vibration source, although there are examples of ground‐borne vibration causing interference out to distances greater than 200 ft (FTA 2018). When roadways are smooth, vibration from traffic, even heavy trucks, is rarely perceptible. It is assumed for mo st
projects that the roadway surface will be smooth enough that ground‐borne vibration from street traffic will not exceed the impact criteria; however, both construction of a project and freight train operations on railroad tracks could res ult in ground‐borne vibration that may be perceptible and annoying.

Ground‐borne noise is not likely to be a problem because noise arriving via the normal airborne path will usually be greater than ground‐borne noise. Ground‐borne vibration has the potential to disturb people and damage buildings. Although it is very rare for train‐ induced ground‐borne vibration to cause cosmetic building damage, it is not uncommon for heavy‐duty construction processes (e.g., blasting and pile driving) to cause vibration of sufficient amplitudes to damage nearby buildings (FTA 2018). Ground‐borne vibration is usually measured in terms of vibration velocity, either th e root‐ mean‐square (RMS) velocity or peak particle velocity (PPV). The RMS velocity is best for characterizing human response to building vibration, and PPV is used to characterize potential for damage. Decibel notation acts to compress the range of numbers required to describe vibration.

Vibration velocity level in decibels is defin ed as the following:

Lv = 20 log10 [V/Vref]
where Lv is the VdB, V is the RMS velocity amplitude, and Vref is the reference velocity amplitude, or 1 x 10‐6 inches/second (in/sec) used in the United States.

REGULATORY SETTING
Federal Regulations
Federal Transit Administration
Noise. The construction noise criteria included in the Federal Transit Administration (FTA) Transit Noise and Vibration Impact Assessment Manual (2018) was used to evaluated potential construction noise impacts because Section 11.44.080 of the City’s Municipal Code does not have daytime construction noise level limits for activities that occur within the specified hour s. Table C shows the FTA’s Detailed Assessment Daytime Construction Noise Criteria based on the composite noise levels for each construction phase.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 11 Table C: Detailed Assessment Daytime
Construction Noise Criteria
Land Use  Daytime 1‐hour Leq (dBA)
Residential  80
Commercial   85
Industrial  90
Source: Transit Noise and Vibration Impact Assessment Manual (FTA 2018). dBA = A‐weighted decibels
Leq = equivalent continuous sound level

Vibration. Vibration standards included in the Federal Transit Administration (FTA) Transit Noise and Vibration Impact Assessment Manual (2018) are used in this analysis for ground‐borne vibration impacts on human annoyance. Table D provides the criteria for assessing the potential for interference or annoyance from vibration levels in a building.

Table D: Interpretation of Vibration Criteria for Detailed Analysis Land Use  Maximum Lv (VdB)1  Description of Use
Workshop  90  Vibration that is distinctly felt. Appropriate for workshops and similar areas not as sensitive to vibration.

Office  84  Vibration that can be felt. Appropriate for office and similar areas not as sensitive to vibration.

Residential Day  78  Vibration that is barely felt. Adequate for computer equipment and low‐power optical microscopes (up to 20X).

Residential Night and
Operating Rooms  72
Vibration is not felt, but ground‐borne noise may be audible inside quiet rooms.

Suitable for medium‐power optical microscopes (100X) and other equipment of low sensitivity.

Source: Transit Noise and Vibration Impact Assessment Manual (FTA 2018). 1   As measured in 1/3‐octave bands of frequency over the frequency range of 8 to 80 Hz.

FTA = Federal Transit Administration
Hz = hertz
LV = velocity in decibels
VdB = vibration velocity decibels

The criteria for environmental impact from ground‐borne vibration and noise are based on the maximum levels for a single event. Table E lists the potential vibration building damage criteria associated with construction activities, as suggested in the Transit Noise and Vibration Impact Assessment Manual (FTA 2018). FTA guidelines show that a vibration level of up to 102 VdB (equivalent to 0.5 in/sec in PPV [FTA 2
018]) is considered safe for buildings consisting of reinforced concrete, steel, or timber (no plaster), and would not result in any construction vibration damage.

For non‐engineered timber and masonry buildings, the construction building vibration damage criterion is 94 VdB (0.2 in/sec in PPV).

Table E: Construction Vibration Damage Criteria
Building Category  PPV (in/sec)  Approximate LV (VdB)1
Reinforced concrete, steel, or timber (no plaster)  0.50  102 Engineered concrete and masonry (no plaster)  0.30  98
Non‐engineered timber and masonry buildings  0.20  94
Buildings extremely susceptible to vibration damage  0.12  90 Source: Transit Noise and Vibration Impact Assessment Manual (FTA 2018). 1  RMS vibration velocity in decibels (VdB) is 1 µin/sec. µin/sec = microinches per second
FTA = Federal Transit Administration
in/sec = inches per second
LV = velocity in decibels
PPV = peak particle velocity
RMS = root‐mean‐square
VdB = vibration velocity decibels

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 12 Local Regulations
City of Santa Clarita
Noise Element. The City’s General Plan Noise Element lists the objectives and policies required to meet the City’s noise‐related goals. The following lists the applicable goals, objectives, and policies, for the proposed project.
 Goal N1: A healthy and safe noise environment for Santa Clarita Valley residents, employees, and visitors.
○ Objective N1.1: Protect the health and safety of the residents of the Santa Clarita Valley by the elimination, mitigation, and prevention of significant existing and future noise levels. ■ Policy N1.1.1. Use the Noise and Land Use Compatibility Guidelines contained in Table F (Exhibit N‐8 in the Noise Element of the General Plan), which are consistent with State guidelines, as a policy basis for decisions on land use and development proposals related to noise.
■ Policy N1.1.4. Control noise sources adjacent to residential, recreational, and community facilities, and those land uses classified as noise sensitive.  Goal N2: Protect residents and sensitive receptors from traffic‐generated noise. ○ Objective N2.1: Prevent and mitigate adverse effects of noise generated from traffic on arterial streets and highways through implementing noise reduction standards and programs.
■ Policy N2.1.1. Encourage owners of existing noise‐sensitive uses, and require owners of proposed noise sensitive land uses, to construct sound barriers to protect users from significant noise levels, where feasible and appropriate. ■ Policy N2.1.2. Encourage the use of noise absorbing barriers, where appropriate.  Goal N3: Protect residential neighborhoods from excessive noise. ○ Objective N3.1: Prevent and mitigate significant noise levels in residential neighborhoods. ■ Policy N3.1.1. Require that developers of new single‐family and multi‐family residential neighborhoods in areas where the ambient noise levels exceed 60 dBA CNEL provide mitigation measures for the new residences to reduce interior noise levels to 45 dBA CNEL, based on future traffic and railroad noise levels. ■ Policy N3.1.2. Require that developers of new single‐family and multi‐family residential neighborhoods in areas where the projected noise levels exceed 65 dBA CNEL provide mitigation measures (which may include noise barriers, setbacks, and site design) for new residences to reduce outdoor noise levels to 65 dBA CNEL, based on future traffic conditions. This requir
ement would apply to rear yards areas for single‐family developments, and to private open space and common recreational and open space areas for multi‐family developments.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 13 Table F: City of Santa Clarita Noise and Land Use Compatibility Guidelines Land Use Category  Community Noise Exposure, Ldn or CNEL, dB 55  60  65  70  75  80  85
Residential – Low Density
Single Family, Duplex, Mobile Homes

Residential
Multi‐Family

Transient Lodging
Motels, Hotels

Schools, Libraries, Churches, Hospitals,
Nursing Homes

Auditoriums, Concert Halls, Amphitheaters

Sports Arena, Outdoor Spectator Sports

Playgrounds, Neighborhood Parks

Golf Courses, Riding Stables, Water
Recreation, Cemeteries

Office Buildings, Business Commercial and
Professional

Industrial, Manufacturing, Utilities,
Agriculture

Normally
Acceptable
Specified land use is satisfactory, based upon the assumption that any buildings involved are of normal conventional construction, without any special noise insulation requirements.

Conditionally
Acceptable
New construction or development should be undertaken only after a detailed analysis of noise reduction requirements is made and needed noise insulation features included in the design.

Conventional construction, but with closed windows and fresh air supply systems or air conditioning will normally suffice.

Normally
Unacceptable
New construction or development should generally be discouraged. If new construction or development does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise insulation features included in the design. Sound walls, window upgrades, and site design modifications may be needed in order to achieve City standards.

Clearly
Unacceptable
New construction or development should generally not be undertaken.

Source: City of Santa Clarita General Plan Noise Element (2011b).

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 14 ■ Policy N3.1.3. Through enforcement of the applicable Noise Ordinance, protect residential neighborhoods from noise generated by machinery or activities that produce significant discernable noise exceeding recommended levels for residential uses. ■ Policy N3.1.4. Require that those responsible for construction activities develop techniques to mitigate or minimize the noise impacts on residences, and adopt standards that regulate noise from construction activities that occur in or near residential neighborhoods.
■ Policy N3.1.9. Implement a buyer and renter notification program for new residential developments where appropriate, to educate and inform potential buyers and renters of the sources of noise in the area and/or new sources of noise that may occur in the future. As determined by the reviewing authority, notification may be appropriate in the following areas:
a. Within one mile of Six Flags Magic Mountain theme park, potential buyers and renters should receive notice that noise may occasionally be generated from this facility and that the frequency and loudness of noise events may change over time. b. Within 1,000 feet of the railroad, potential buyers and renters should receive notice that noise may occasionally be generated from this facility and that the frequency and loudness of noise events may change over time.
c. Within 200 feet of commercial uses in mixed‐use developments, potential buyers and renters should receive notice that the commercial uses within the mixed‐use developments may generate noise in excess of levels typically found in residential areas, that the commercial uses may change over time, and the associated noise levels and frequency of noise events ma y change along with the use. d. Within 1,000 feet of the Saugus Speedway, in the event speedway operations are resumed in the future.

Municipal Code. Section 11.44.040 of the City’s Municipal Code has established daytime and nighttime exterior noise limits in regions designated as residential, and commercial and manufacturing, as shown in Table G.

Table G: City of Santa Clarita Maximum Exterior Noise Limits Region  Time Period  Noise Level
(dBA)
L25
(15 minutes)1
L8
(5 minutes)2
L2
(1 minute)3
Residential Zone  Daytime  7:00 a.m. to 9:00 p.m.  65  70  75  85 Nighttime  9:00 p.m. to 7:00 a.m.  55  60  65  75
Commercial and
Manufacturing
Daytime  7:00 a.m. to 9:00 p.m.  80  85  90  100
Nighttime  9:00 p.m. to 7:00 a.m.  70  75  80  90
Source: City of Santa Clarita, Municipal Code. (2022).

Note: A correction to the noise limits of minus 5 dB for repetitive impulsive noise, steady whine, screech, or hum. 1  Noise occurring more than 5 minutes but less than 15 minutes per hour. 2  Noise occurring more than 1 minute but less than 5 minutes per hour. 3  Noise occurring less than 1 minute per hour.
dBA = A‐weighted decibels

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 15 Section 11.44.080 of the City’s Municipal Code prohibits any noise level from the use or operation of any machinery, equipment, pump, fan, air conditioning apparatus, refrigerating equipment, motor vehicle, or other mechanical or electrical device, or in repairing or rebuilding any motor vehicle, which exceeds the noise limits as set forth in Section 11.44.040  at any property line.

Section 11.44.080 of the City’s Municipal Code prohibits construction work that requires a building permit from the City on sites within 300 ft of a residentially zoned property except between the hours of 7:00 a.m. to 7:00 p.m. Monday through Friday and between the hours of 8:00 a.m. to 6:00 p.m. on Saturday. No work shall
be performed on New Year’s Day, Independence Day,
Thanksgiving, Christmas, Memorial Day, and Labor Day.

EXISTING SETTING
Land Uses in the Project Vicinity
Land uses surrounding the proposed building include residences to the west and commercial uses to the north, east, and south. Land uses surrounding the new parking lot include residences to the north and southeast and commercial uses to the east, south, and west. Bouquet Canyon Road and the Metrolink rail are located east of the project.

Overview of the Existing Noise Environment
Transportation facilities make up the primary existing noise sources in the project area. Traffic on Bouquet Canyon Road and other roadways in the vicinity are a steady source of ambient noise. The Metrolink rail line to the east is a source of intermittent noise. Other sources of noise in the project area include commer
cial activity.

Ambient Noise Measurements
Short‐Term Noise Measurements
Short‐term (15‐minute) noise level measurements were conducted on January 25 and 26, 2021, using a Larson Davis Model 831 Type 1 sound level meter. Table H shows the results of the short‐ term noise level measurements along with a description of the measurement locations and noise sources that occurred durin
g the measurement. As shown in Table H, the measured average noise levels in the project vicinity range from 51.8 to 69.1 dBA Leq, and the instantaneous maximum noise levels range from 66.4 to 84.0 dBA Lmax. Figure 6 shows the short‐term monitoring locations.

Long‐Term Noise Measurements
Two long‐term (24‐hour) noise level measurements were conducted from January 25 to January 26, 2021, using a Larson Davis Spark 706RC Dosimeter. Tables I and J show the hourly Leq, Lmax, and Lmin results from the long‐term noise level measurements, and Table K summarizes the long‐term noise level measurements. As shown in Table K, the noise levels on the project site range from 46.1 to

61.9 dBA Leq and calculated CNEL levels range from 60.4 to 62.0 dBA. Figure 6 shows the long‐term monitoring locations.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 16 Table H: Short‐Term Ambient Noise Level Measurements Monitor
No.  Location  Date  Start Time  Noise Level (dBA)  Noise Source(s) Leq  Lmax  Lmin ST‐1
26135 Bouquet Canyon Road. On the dirt
landscaping path in front of the IHOP
restaurant. Approximately 35 ft from the
edge of Bouquet Canyon Road.
1/26/21  4:25 PM  69.1  84.0  52.0
Traffic on Bouquet
Canyon Road.

ST‐2
26135 Bouquet Canyon Road. On the
north end of the parking lot.

Approximately 15 ft south from the wall.
1/25/21  3:18 PM  51.8  66.4  46.2
Traffic on Bouquet
Canyon Road and birds.

ST‐3
Vacant lot south of the Las Flores
Apartments. Approximately 28 ft south of
the wall and 18 ft west of the parking lot
edge.
1/26/21  4:55 PM  52.3  71.4  44.6
Traffic on Bouquet
Canyon Road and birds.

Source: Compiled by LSA Associates, Inc. (2021).
dBA = A‐weighted decibels
ft = foot/feet
Leq = equivalent continuous sound level
Lmax = maximum measured sound level
Lmin = minimum measured sound level
SOURCE: Google Earth (2021)
FEET
2001000
FIGURE 6
Noise Monitoring Locations
Promenade Flats
I:\HAV2001\G\Noise_Monitor_Locs.ai (10/6/2023)
- Project Site Boundary
- Short-term Noise Monitoring Location
- Long-term Noise Monitoring Location
LEGEND
LT-1LT-1LT-1
ST-1ST-1ST-1
ST-2ST-2ST-2
ST-3ST-3ST-3
ST-1ST-1ST-1LT-2LT-2LT-2 LT-1LT-1LT-1

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 18 Table I: Long‐Term (24‐Hour) Noise Level Measurement Results at LT‐1 Start Time  Date  Noise Level (dBA)
Leq  Lmax  Lmin
1  4:00 PM  1/25/21  58.2  90.8  47.4
2  5:00 PM  1/25/21  59.1  85.0  47.6
3  6:00 PM  1/25/21  56.7  78.1  46.6
4  7:00 PM  1/25/21  58.0  86.2  45.7
5  8:00 PM  1/25/21  54.9  74.7  43.6
6  9:00 PM  1/25/21  52.8  72.4  41.9
7  10:00 PM  1/25/21  52.2  80.1  42.0
8  11:00 PM  1/25/21  49.3  67.8  41.0
9  12:00 AM  1/26/21  48.7  67.5  41.6
10  1:00 AM  1/26/21  47.9  64.6  40.9
11  2:00 AM  1/26/21  48.1  65.8  41.0
12  3:00 AM  1/26/21  49.6  67.3  42.0
13  4:00 AM  1/26/21  55.8  88.0  42.3
14  5:00 AM  1/26/21  58.7  88.2  46.5
15  6:00 AM  1/26/21  59.3  86.3  47.8
16  7:00 AM  1/26/21  59.7  76.8  52.1
17  8:00 AM  1/26/21  59.1  86.1  50.8
18  9:00 AM  1/26/21  58.9  86.7  52.2
19  10:00 AM  1/26/21  58.7  86.7  50.8
20  11:00 AM  1/26/21  59.1  79.0  50.0
21  12:00 PM  1/26/21  57.0  79.0  46.2
22  1:00 PM  1/26/21  58.4  85.9  46.5
23  2:00 PM  1/26/21  59.6  85.0  49.1
24  300 PM  1/26/21  59.3  86.6  48.8
Source: Compiled by LSA Associates, Inc. (2021).
dBA = A‐weighted decibel
Leq = equivalent continuous sound level
Lmax = maximum measured sound level
Lmin = minimum measured sound level

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 19 Table J: Long‐Term (24‐Hour) Noise Level Measurement Results at LT‐2 Start Time  Date  Noise Level (dBA)
Leq  Lmax  Lmin
1  4:00 PM  1/25/21  58.2  90.8  47.4
2  5:00 PM  1/25/21  59.1  85.0  47.6
3  6:00 PM  1/25/21  56.7  78.1  46.6
4  7:00 PM  1/25/21  58.0  86.2  45.7
5  8:00 PM  1/25/21  54.9  74.7  43.6
6  9:00 PM  1/25/21  52.8  72.4  41.9
7  10:00 PM  1/25/21  52.2  80.1  42.0
8  11:00 PM  1/25/21  49.3  67.8  41.0
9  12:00 AM  1/26/21  48.7  67.5  41.6
10  1:00 AM  1/26/21  47.9  64.6  40.9
11  2:00 AM  1/26/21  48.1  65.8  41.0
12  3:00 AM  1/26/21  49.6  67.3  42.0
13  4:00 AM  1/26/21  55.8  88.0  42.3
14  5:00 AM  1/26/21  58.7  88.2  46.5
15  6:00 AM  1/26/21  59.3  86.3  47.8
16  7:00 AM  1/26/21  59.7  76.8  52.1
17  8:00 AM  1/26/21  59.1  86.1  50.8
18  9:00 AM  1/26/21  58.9  86.7  52.2
19  10:00 AM  1/26/21  58.7  86.7  50.8
20  11:00 AM  1/26/21  59.1  79.0  50.0
21  12:00 PM  1/26/21  57.0  79.0  46.2
22  1:00 PM  1/26/21  58.4  85.9  46.5
23  2:00 PM  1/26/21  59.6  85.0  49.1
24  300 PM  1/26/21  59.3  86.6  48.8
Source: Compiled by LSA Associates, Inc. (2021).
dBA = A‐weighted decibel
Leq = equivalent continuous sound level
Lmax = maximum measured sound level
Lmin = minimum measured sound level

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 20 Table K: Long‐Term Ambient Noise Level Measurements
Monitor
No.  Location  Start
Date
Start
Time
Duration
(hours)
Noise Level (dBA)  Noise Sources Leq  CNEL
LT‐1
26135 Bouquet Canyon
Road. On the west side of
the parking lot.
1/25/21  4:00 PM  24  47.9–59.7  62.0
Traffic on Bouquet Canyon
Road, Metrolink train, and
commercial activity.

LT‐2
26135 Bouquet Canyon
Road. On the east side of
the parking lot.
1/25/21  4:00 PM  24  46.1–61.9  60.4
Traffic on Bouquet Canyon
Road, Metrolink trains, and
commercial activity.

Source: Compiled by LSA Associates, Inc. (2021).

CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
Leq = equivalent continuous sound level

Existing Aircraft Noise
The Whiteman, Agua Dulce, and Van Nuys Airports are approximately 12.8 miles southwest, 13.8 miles northeast, and 14 miles south of the project site, respectively. Based on the airport influence area map in the Los Angeles County Airport Land Use Plan (Los Angeles County ALUC 2004), the project site is well beyond the airport influence areas for any  of these airports.

Existing Traffic Noise
The Federal Highway Administration (FHWA) Highway Traffic Noise Prediction Model (FHWA‐RD‐77‐ 108) was used to evaluate highway traffic‐related noise conditions along roadway segments in the project vicinity. This model requires various parameters, including traffic volumes, vehicle mix, vehicle speed, and roadway geometry to compute typical equivalent noise levels during daytim e, evening, and nighttime hours. The resultant noise levels are weighted and summed over 24‐hour periods to determine the CNEL values. The standard vehicle mix for Southern California roadways was used for traffic on these roadway segments. The 2008 average daily traffic (ADT) volume of 37,650 on Bouquet Canyon Road was obtained from the City’s Traffic Flow  Map (City of Santa Clarita 2013). The City’s Traffic Flow Map show that the ADT volumes decreased greatly from 2008 to 2013 and were not projected to the existing 2021 year. For the reasons described above, the existing 2021 ADT volumes were assumed to be equivalen t to the 2008 ADT volumes. Table L shows the modeled 24‐hour CNEL levels for the existing conditions. These noise levels represent the worst‐ case scenario, which assumes no shielding is provided between the traffic and the location where the noise contours are drawn. The specific assumptions used in developing thes e noise levels and model printouts are provided in Attachment B.

As shown in Table L, traffic noise levels along Bouquet Canyon Road directly adjacent to the project site are moderately high, with the 70, 65, and 60 dBA CNEL noise contours extending 112 ft, 344 ft, and 1,084 ft, respectively, from the roadway centerli
ne.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 21 Table L: Existing Traffic Noise Levels
Roadway Segment  ADT
Centerline
to
70 dBA
CNEL (ft)
Centerline
to
65 dBA
CNEL (ft)
Centerline
to
60 dBA
CNEL (ft)
CNEL (dBA) 50 ft
from Centerline
of Outermost
Lane
Bouquet Canyon Road north of
Magic Mountain Parkway  37,650  112  344  1,084  71.7
Source: Compiled by LSA Associates, Inc. (2021).

Note: Noise modeling performed using “Soft” setting and Southern California traffic percentages.

ADT = average daily traffic
CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
ft = foot/feet

IMPACTS
Short‐Term Construction Noise Impacts
Two types of short‐term noise impacts would occur during project construction. The first type would be from construction crew commutes and the transport of construction equipment and materials to the project site and would incrementally raise noise levels on roadways leading to the site. The pieces of construction equipment for construction activities would move on site, would remain for the duration of each construction phase, and would not add to the daily traffic vol ume in the project
vicinity. Although there would be a relatively high single‐event noise exposure potential causing intermittent noise nuisance (passing trucks at 50 ft would generate up to a maximum of 84  dBA), the effect on longer‐term ambient noise levels would be small because the number of daily construction‐related vehicle trips is small compared to existing daily traffic volume on Bouquet Canyon Road. The demolition phase would generate the most trips of all of the construction phases, at a Passenger Car Equivalent
(PCE) of 260 trips per day based on the California Emissions Estimator Model (Version 2022.1). Based on Table L, Bouquet Canyon Road has an estimated existing ADT volume of 37,650 adjacent to the project site. Based on the information above, construction‐related traffic noise would increase by 0.03 dB A. A noise level increase of less than 3 dBA would not be perceptible to the human ear in an outdoor environment. Therefore, no short‐term, construction‐ related impacts associated with worker commutes and transport of construction equipment and material to the project site would occur, and no noise reduction measures would be  required.

The second type of short‐term noise impact is related to noise generated from construction activities. The proposed project anticipates site preparation, grading, building construction, paving, and architectural coating phases of construction. Construction is performed in discrete steps, each of which has its own mix of equi pment and, consequently, its own noise characteristics. These various sequential phases change the character of the noise generated on a project site. Therefore, the noise levels vary as construction progresses. Despite the variety in the type and size of construction equipment, similarities in the dominant noise sources and patterns of operation allow construction‐related noise ranges to be categorized by work phase . Table M lists the Lmax
recommended for noise impact assessments for typical construction equipment included in the FHWA’s Highway Construction Noise Handbook (2006), based on a distance of 50 ft between the equipment and a noise receptor.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 22 Table M: Typical Construction Equipment Noise Levels Equipment Description  Acoustical Usage Factor1 (%)  Maximum Noise Level (Lmax) at 50 ft2 Backhoe  40  80
Compactor (ground)  20  80
Compressor  40  80
Crane  16  85
Dozer  40  85
Dump Truck  40  84
Excavator  40  85
Flatbed Truck  40  84
Forklift  20  85
Front‐End Loader  40  80
Grader  40  85
Impact Pile Driver  20  95
Jackhammer  20  85
Pavement Scarifier  20  85
Paver  50  85
Pickup Truck  40  55
Pneumatic Tools  50  85
Pump  50  77
Rock Drill  20  85
Roller  20  85
Scraper  40  85
Tractor  40  84
Welder  40  73
Source: Highway Construction Noise Handbook, Table 9.1 (FHWA 2006).

Note: The noise levels reported in this table are rounded to the nearest whole number. 1  The usage factor is the percentage of time during a construction noise operation that a piece of construction equipment is operating at full power.
2  Maximum noise levels were developed based on Specification 721.560 from the CA/T program to be consistent with the City of Boston, Massachusetts, Noise Code for the “Big Dig” project.

CA/T = Central Artery/Tunnel
FHWA = Federal Highway Administration
ft = foot/feet
Lmax = maximum instantaneous noise level

Typical noise levels range up to 88 dBA Lmax at 50 ft during the noisiest construction phases. The site preparation and grading phase tends to generate the highest noise levels because the noisiest construction equipment is earthmoving equipment. Earthmoving equipment includes excavating machinery such as backhoes, bulldozers, excavators, and front‐end loaders. Earthmoving and compacting equipment include compactors, scrapers, and graders. Typical operating cycles fo r these types of construction equipment may involve 1 to 2 minutes of full‐power operation followed by 3 to 4 minutes at lower power settings.

Project construction is expected to require the use of a grader, bulldozer, and water truck/pickup truck. Noise associated with the use of construction equipm ent is estimated to be between 55 dBA Lmax and 85 dBA Lmax at a distance of 50 ft from the active construction area for the site preparation and grading phase. As shown in Table M, the maximum noise level generated by a grader is assumed to be approximately 85 dBA Lmax at 50 ft from the grader. The dozer would generate approximately 85 dBA Lmax at 50 ft. The maximum noise level generated by a water truck/pickup truck is approximately 55 dBA Lmax at 50 ft. Each doubling of the sound sources with equal strength increases the noise level by 3 dBA. Assuming that each piece of construction equipment operates at some distance from the other equipment, the worst‐ case combined noise level during construction would

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 23 be 88 dBA Lmax at a distance of 50 ft from the active construction area. Based on a usage factor of 40 percent, the worst‐case combined noise level during construction would be 84 dBA Leq at a distance of 50 ft from the active construction area.

The closest residences are located approximately 175 ft west from the center of the proposed building and approximately 75 ft north from the center of the new parking area, which may be subject to short‐term construction noise reaching 77 dBA Lmax (73 dBA Leq) and 82 dBA Lmax (78 dBA Leq), respectively. Construction noise is temporary and would stop once project construction is completed. The project would be required to comply with the construction hours allowed under the City’s Municipal Code Noise Ordinance, and standard conditions for construction listed below would minimize construction noise. Furthermore, construction related noise levels would be below the FTA noise level standard of 80 dBA Leq for residential uses. Therefore, no noise impacts from construction activities would occur, and no noise reduction measures are required.  The construction contractor shall limit construction activities to between the hours of 7:00 a.m. and 7:00 p.m. Monday through Friday and between the hours of 8:00 a.m. and 6:00 p.m. on Saturday. No construction shall be permitted outside
of these hours or on Sundays and New
Year’s Day, Independence Day, Thanksgiving, Christmas, Memorial Day, and Labor Day.  During all project site excavation and grading, the project contractors shall equip all construction equipment, fixed or mobile, with properly operating and maintained mufflers consistent with manufacturers’ standards.
 The construc
tion contractor shall locate equipment staging in areas that will create the greatest distance between construction‐related noise sources and most noise‐sensitive receptors nearest the project site during all project construction.
 The construction contractor shall place all stationary construction equipment so that the emitted noise is directed away from th
e sensitive receptors nearest the project site.

Short‐Term Construction Vibration Impacts
This construction vibration impact analysis discusses the level of human annoyance using vibration levels in VdB and will assess the potential for building damages using vibration levels in PPV (in/sec) because vibration levels calculated in RMS are best for characterizing human response to building vibration whereas vibration level in PPV is best used to characterize potential fo r damage. As shown previously in Table E, the FTA guidelines indicate that a vibration level up to 102 VdB (equivalent to

0.5 PPV [in/sec]) is considered safe for buildings consisting of reinforced concrete, steel, or timber (no plaster) and would not result in any construction vibration damage  (FTA 2018). For a non‐ engineered timber and masonry building, the construction vibration damage criterion is 94 VdB (0.2 PPV [in/sec]). For a fragile building, the construction vibration damage criterion is 90 VdB (0.12 PPV [in/sec]).

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 24 Table N shows the reference vibration levels at a distance of 25 ft for each type of standard construction equipment from the FTA’s Transit Noise and Vibration Impact Assessment Manual (2018). Outdoor site preparation and grading for the proposed project are expected to require the use of a small bulldozer (with rubber tire s) and loaded trucks, which would generate ground‐borne vibrations of up to 58 VdB (0.003 PPV [in/sec]) and 86 VdB (0.076 PPV [in/sec]), respectively, when measured at 25 ft.

Table N: Vibration Source Amplitudes for Construction Equipment Equipment  Reference PPV/LV at 25 ft
PPV (in/sec)  LV (VdB)1
Pile Driver (Impact), Typical  0.644  104
Pile Driver (Sonic), Typical  0.170  93
Vibratory Roller  0.210  94
Large Bulldozer  0.089  87
Caisson Drilling  0.089  87
Loaded Trucks2  0.076  86
Jackhammer  0.035  79
Small Bulldozer2  0.003  58
Sources: Transit Noise and Vibration Impact Assessment Manual (FTA 2018). 1 RMS vibration velocity in decibels (VdB) is 1 µin/sec. 2 Equipment shown in bold is expected to be used on site. µin/sec = microinch/microinches per second
ft = foot/feet
FTA = Federal Transit Administration
in/sec = inches per second
LV = velocity in decibels
PPV = peak particle velocity
RMS = root‐mean‐square
VdB = vibration velocity decibels

The greatest vibration levels are anticipated to occur during the site preparation and grading phase.

All other phases are expected to result in lower vibration levels. The distance to the nearest buildings for vibration impact analysis is measured between the nearest off‐site buildings and the project boundary (assuming the construction equipment would be used at or near th e project boundary), because vibration impacts normally occur within the buildings. An exception to this would be the location of loaded trucks. Loaded trucks would be limited to certain areas on the project site and would not operate at the project construction boundary.

The following provides the formula for vibration transm ission:

LvdB (D) = LvdB (25 ft) – 30 Log (D/25) and PPVequip = PPVref x (25/D)1.5 Table O lists the projected vibration level from various construction equipment expected to be used on the project site of the proposed building and the parking lot to the nearest buildings in the project vicinity. As shown in Table O, the closest residential buildings are located west of the proposed building and southeast of the proposed park ing lot site and would experience vibration levels of up to 84 VdB (0.058 PPV [in/sec]) and 93 VdB (0.164 PPV [in/sec]), respectively. These vibration levels have the potential to result in community annoyance because vibration levels would exceed the FTA annoyance threshold of 78 VdB for daytime reside nces. However, this vibration level

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 25 Table O: Summary of Construction Equipment and Activity Vibration Construction
Area  Land Use  Direction  Equipment/
Activity
Reference Vibration Level at 25 ft  Distance
(ft)
Maximum Vibration Level
VdB  PPV  VdB  PPV
Proposed
Building
Commercial  North  Small Bulldozers  58  0.003  10  70  0.012 Loaded Trucks  86  0.076  301  84  0.058
Commercial  East  Small Bulldozers  58  0.003  10  70  0.012 Loaded Trucks  86  0.076  301  84  0.058
Commercial  South  Small Bulldozers  58  0.003  45  50  0.001 Loaded Trucks  86  0.076  45  78  0.031
Residential  West  Small Bulldozers  58  0.003  30  56  0.002 Loaded Trucks  86  0.076  30  84  0.058
Proposed
Parking Lot
Commercial  North  Small Bulldozers  58  0.003  40  52  0.001 Loaded Trucks  86  0.076  40  80  0.038
Commercial  East  Small Bulldozers  58  0.003  60  47  0.001 Loaded Trucks  86  0.076  60  75  0.020
Residential  Southeast  Small Bulldozers  58  0.003  15  65  0.006 Loaded Trucks  86  0.076  15  93  0.164
Commercial  South  Small Bulldozers  58  0.003  25  58  0.003 Loaded Trucks  86  0.076  25  86  0.076
Commercial  West  Small Bulldozers  58  0.003  10  70  0.012 Loaded Trucks  86  0.076  301  84  0.058
Source: Compiled by LSA Associates, Inc. (2021).

Note: The FTA‐recommended building damage threshold is 0.2 PPV (in/sec) or approximately 94 VdB at the receiving building structure. 1  Loaded trucks would be limited to certain areas on the project site and would not operate at the project construction boundary. ft = foot/feet
in/sec = inches per second
FTA = Federal Transit Administration
PPV = peak particle velocity
VdB = vibration velocity decibels

would not have the potential to result in building damage because vibration levels would not exceed the FTA damage threshold of 94 VdB (0.2 PPV [in/sec]) since the residential buildings would be constructed of non‐engineered timber and masonry.

Also, Table O shows that the closest commercial buildings, which are located north and east of the proposed bui
lding and west of the proposed parking lot site, would experience vibration levels of up to 84 VdB (0.058 PPV [in/sec]). This vibration level would not have the potential to result in community annoyance because the vibration levels would exceed the FTA annoyance threshold of 84 VdB for buildings not as
sensitive to vibration. In addition, this vibration level would not have the potential to result in building damage because vibration levels would not exceed the FTA damage threshold of 94 VdB (0.2 PPV [in/sec]) since the commercial buildings would be constructed of non‐ engineered timber and masonry. Oth er adjacent buildings to the project site are farther away and would experience lower vibration levels. Therefore, no construction vibration impacts would occur, and no vibration reduction measures are required.

Long‐Term Aircraft Noise Impacts
As discussed above, the Whiteman, Agua Dulce, and Van Nuys Airports are approximately 12.8 miles southeast, 13.8 miles northeast, and 14 miles south of the project site, respectively. Based on the airport influence area map for these airports in the Los Angeles County Airport Land Use Plan (Los Angeles County ALUC 2004), the projec t site is well beyond the airport influence area for noise impacts. Therefore, the project would not expose people working or residing in the project area to excessive noise levels.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 26 Long‐Term Traffic Noise Impacts
The proposed project is estimated to generate an ADT volume of 636 based on the proposed 7,266.10 sf of retail, 3,027.40 sf of rooftop yoga studio (health/fitness club), and 30 multifamily residential units from the Institute of Transportation Engineers (ITE) Trip Generation Manual, 11th Edition (2021). As discussed above, the existing 2021 ADT volume on Bouquet Can yon Road is assumed to be 37,650. It takes a doubling of traffic to increase traffic noise levels by 3 dBA. The project‐related traffic would increase traffic noise along Bouquet Canyon Road by up to 0.07 dBA. A noise level increase of less than 3 dBA would not be perceptible to the hu man ear in an outdoor environment. Therefore, no traffic noise impacts from project‐related traffic on off‐site sensitive receptors would occur, and no noise reduction measures are required.

Land Use Compatibility
The proposed project’s on‐site uses were assessed based on the City’s exterior noise standard of 65 dBA CNEL contained in the Noise Element of the City’s General Plan and an interior noise standard of 45 dBA CNEL, which is consistent with the State’s noise insulation standards.

Exterior Noise Levels
As discussed above, exterior noise level s in the project area include traffic on Bouquet Canyon Road, train noise from the Metrolink rail line, and commercial activity. The project site is located well beyond the airport influence area of the closest airports and the contribution of aircraft noise in the project area would be min imal to negligible. The long‐term noise level measurements at LT‐1 and LT‐2 are composite noise levels of all the noise sources in the project area described above, and the calculated CNEL levels at LT‐1 and LT‐2 were 62.0 and 60.4 dBA, respectively.

To assess the future ex terior noise levels on the project site, the composite existing exterior noise level at the ground floor of Receptors R‐1 and R‐2 were calculated based on traffic noise on Bouquet Canyon Road and train noise from the Metrolink rail line to ensure that it is consistent with the measured noise level. Figure 7 shows the model
ed receptor locations. Receptor R‐1 represents the
area east of the proposed building, which is in the approximate location of LT‐1. Receptor R‐2 represents the area west of the proposed building, which is in the approximate location of LT‐2.

Existing traffic noise le
vels on Bouquet Canyon Road are shown in Table L, which has a traffic noise level of 65 dBA CNEL at 344 ft from the roadway centerline. The existing commercial buildings north, east, and south of the project site would provide an estimated traffic noise reduction of 5 dBA and 3 dBA at Rece
ptors R‐1 and R‐2, respectively. The existing train noise was estimated to be 62.4 dBA CNEL at 50 ft based on a reference noise level of 57 dBA Leq at 50 ft with 21 daytime trips, 4 evening trips, and 5 nighttime trips. The existing commercial buildings north, east, and south of the project site would provide an estimated train noise reduction of 6 dBA and 4 dBA at Receptors R‐1 and R‐2, respectively.

Table P shows that the calculated ex isting composite noise levels at Receptors R‐1 and R‐2 are 63 and 61 dBA CNEL, respectively, which are levels considered in agreement with the measured noise levels at LT‐1 and LT‐2. Table C‐1 in Attachment C shows the detailed noise calculations for the existing ground floor nois
e levels at Receptors R‐1 and R‐2.

SOURCE: Google Earth (2021)
FEET
100500
FIGURE 7
Bouquet Canyon RdBouquet Canyon RdBouquet Canyon Rd
Modeled Receptor Locations
Promenade Flats
I:\HAV2001\G\Modeled_Receptor_Locs.ai (10/6/2023)
Project Site Boundary
Receptor Location
LEGEND
R-1R-1R-1
R-1R-1R-1
R-2R-2R-2

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 28 Table P: Exterior and Interior Noise Levels
Receptor No.

Noise Level (dBA CNEL)  Noise Reduction
to Meet 45 dBA
CNEL Interior
Noise Standard
Existing
Ground Floor
Exterior
Existing
Upper Floor
Exterior
Future
Upper Floor
Exterior
Interior
with Windows
and Doors Open1
R‐1  63  68  69.0  57.02  24.0
R‐2  61  64  65.0  53.0  20.0
Source: Compiled by LSA Associates, Inc. (2021).
1   Interior noise levels were calculated using an exterior‐to interior noise reduction of 12 dBA based on the EPA’s Protective Noise Levels (EPA 1978) and standard construction in California (warm climate) with a combination of exterior walls, doors, and windows. 2   Numbers shown in bold exceed the interior noise standard of 45 dBA CNEL.

CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
EPA = United States Environmental Protection Agency

The existing and future upper floor exterior noise levels were then calculated at Receptors R‐1 and R‐2 without shielding from the existing commercial buildings to the north, east, and south because the proposed residences would be located on the upper floors (floors 2 through 4) and the existing commercial buildings would not provide any noise re duction. The future traffic volume on Bouquet Canyon Road was estimated to have an average daily traffic (ADT) volume of 45,000 based on an ADT capacity of 9,000 vehicles per lane from the General Plan Circulation Element (City of Santa Clarita 2011a) and an existing five‐lane divided roadway (three lanes in the no rthbound direction and two lanes in the southbound direction) on Bouquet Canyon Road in the project area. The future ADT volume of 45,000 would have a traffic noise level of 65 dBA CNEL at a distance of 411 ft based on the FHWA Traffic Noise Prediction Model (FHWA‐RD‐77‐108). This noise leve l represents the worst‐case scenario, which assumes no shielding is provided between the traffic and the location where the noise contours are drawn. The specific assumptions used in developing the noise level and model printout are provided in Attachment B.

Table P shows the existing and future up
per floor exterior noise levels at R‐1 and R‐2. Tables C‐2 and C‐3 in Attachment C shows the detailed noise calculations for the existing and future upper floor noise levels at Receptors R‐1 and R‐2. As shown in Table P, future upper floor exterior noise le vels at Receptors R‐1 and R‐2 are predicted to be 69.0 dBA CNEL and 65.0 dBA CNEL, respectively. The proposed outdoor private living areas (e.g., balconies or common outdoor areas) would have exterior noise levels that exceed the City’s exterior noise standard of 65  dBA CNEL for residential uses in the future as traffic increases. A minimum barrier height of 6 ft surrounding the private balconies of residential dwelling units and the rooftop terrace would provide a minimum noise reduction of 5 dBA and would reduce exterior noise levels to 65 dBA CNEL or below. In addition, the project would com
ply with Policy N3.1.9 in the Noise Element of the General Plan by providing notification to all potential buyers or renters of the residential dwelling units of noise sources in the area, new noise sources that may occur in the future, commerc ial uses that may generate noise in excess of levels for residential uses, that commercial uses may change over time, and that noise levels and frequency of noise events may change along with the change in commercial use because the proposed project would be located within 1,000 ft of the Metrolink rail  line and within 200 ft of commercial uses. Therefore, no exterior noise impacts would occur with implementation of balcony barriers and rooftop terrace barriers and compliance with Policy N3.1.9 in the City’s General Plan Noise Element.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 29 Table P: Exterior and Interior Noise Levels
Receptor No.

Noise Level (dBA CNEL)  Noise Reduction
to Meet 45 dBA
CNEL Interior
Noise Standard
Existing
Ground Floor
Exterior
Existing
Upper Floor
Exterior
Future
Upper Floor
Exterior
Interior
with Windows
and Doors Open1
R‐1  63  68  69  572  24
R‐2  61  64  65  53  20
Source: Compiled by LSA Associates, Inc. (2022).
1   Interior noise levels were calculated using an exterior‐to interior noise reduction of 12 dBA based on the EPA’s Protective Noise Levels (EPA 1978) and standard construction in California (warm climate) with a combination of exterior walls, doors, and windows. 2   Numbers shown in bold exceed the interior noise standard of 45 dBA CNEL.

CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
EPA = United States Environmental Protection Agency

Interior Noise Levels
Table P shows the interior noise levels with windows and doors open for Receptors R‐1 and R‐2.

Interior noise levels with windows and doors open were calculated using an exterior‐to‐interior noise reduction of 12 dBA based on the United States Environmental Protection Agency (EPA) Protective Noise Levels (EPA
1978) and standard construction in California (warm climate) with a combination of exterior walls, doors, and windows. As shown in Table P, interior noise levels with windows and doors open would range from 53 to 57 dBA CNEL, which would exceed the interior noise standard of 45 dBA CNEL. Therefore, mechanical ventilation sy stems such as air conditioning would be required for all residential units so that windows and doors could remain closed for a prolonged period of time. Because the project plans show that air conditioning systems are included as part of the project, no additional measures are required.

Table P also sh
ows that an exterior‐to‐interior noise reduction of 20 to 24 dBA is required to meet the interior noise standard of 45 dBA CNEL. To calculate and estimate the noise reduction provided by an exterior wall assembly, the transmission loss at the octave band frequencies for wall material by type
is combined to provide an overall noise reduction. The rating of the wall and window or windows within the assembly will often be referred to as a sound transmission class (STC) rating.

The program INSUL was used to estimate the window ratings to ensure that compliance is ac hieved.

Based on wall details presented in the project plans, the following elements make up the assumed exterior wall assembly:
 7/8‐inch‐thick, three‐coat stucco
 One layer of 0.5‐inch‐thick plywood or oriented strand board (OSB)  One layer of 5/8‐inch‐thick gypsum board
 2‐inch x 6‐inch wood stud wall channels spaced at 16 inches and a minim um R‐19 fiberglass
insulation
 One layer of 5/8‐inch‐thick gypsum board
In addition to the wall construction details, information from the VPI Quality Windows Endurance Series, which is energy and sound rated, was used to determine wi ndow STC ratings. The required window STC ratings and the composite noise level reduction are provided for the sensitive rooms based on the project floor plans. Attachment D provides the results of the INSUL model.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 30 The results of the analysis indicated that for the living room of the corner units facing east towards Bouquet Canyon Road, windows and glass doors with a minimum rating of STC‐31 are required due to the high wall exposure area and high window‐to‐wall ratio. For all other noise‐ sensitive rooms within the project site (i.e., living room and bedrooms), windows and glass doors with a minimum rating of STC‐28 would achieve interior noise levels of 45 dBA CNEL or below.

Long‐Term Off‐Site Stationary Noise Impacts
The project would be potentially exposed to stationary source noise impacts from truck deliveries and unloading activities, parking lot activities, and heating, ventilation, and air conditioning (HVAC) equipment. The following provides a detailed noise analysis and discussion of each stationary noise source.

Truck Delivery and Truck Unloading Activities
The project would include truck delivery and unloading  activities associated with the first floor retail space. Truck delivery and truck unloading activities would occur in the designated parking space near the IHOP restaurant or near the south side of the proposed building. Existing truck delivery and truck unloading activities occur in the project area for the IHOP res taurant and the commercial uses to the south. Noise levels generated by truck deliveries and truck unloading activities from the proposed retail uses would occur at a similar location as the existing commercial uses to the south and would not increase the ambient noise environment in the project area. Therefore, no noi se impacts from truck deliveries and truck unloading activities would occur, and no noise reduction measures are required.

Parking Lot Activity
The proposed project would include a total of 41 new parking spaces located on an adjacent parcel.

Noise generated from parking lot activities would include noise generated by vehicles traveling at slow speeds, engine start‐up noise, car door slams,
car horns, car alarms, and tire squeals. The
existing residences north of the new parking spaces are already exposed to noise levels generated from parking activities associated with their own parking spaces and from the commercial uses to the east. Noise levels gen
erated by parking activities from the new parking spaces would not increase the ambient noise environment in the project area. Therefore, no noise impacts from parking activities would occur, and no noise reduction measures are required.

HVAC Equipment
The proposed project would include a total of 40 rooftop HVAC units for the proposed residential/ retail
building. The HVAC equipment could operate 24 hours per day. Each HVAC unit associated with the retail spaces would generate a sound power level (SWL) that ranges between 76.0 dBA and

79.0 dBA, which would be equivalent to noise levels of 44.4 dBA Leq and 47.4 dBA Leq at a distance of 50 ft. Each HVAC unit associated with residential uses would generate a sound pressure level (SPL) ranging between 60.0 dBA Leq and 63.0 dBA Leq at a distance of 3.3 ft. At a distance of 50 ft, noise levels would range between 36.3 dBA Leq and 39.3 dBA Leq. The composite noise level of all 40 HVAC units would be 56.2 dBA at a distance of 50 ft. The composite HVAC noise calculations are provided in Attachment E.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 31 The 40 rooftop HVAC units would be shielded by the roofline and parapet, which would provide a minimum noise reduction of 8 dBA. Table Q summarizes the noise levels generated by the rooftop HVAC units at the adjacent land uses. As shown in Table Q, noise levels generated by the rooftop HVAC units wou
ld range from 37.6 to 49.1 dBA Leq. These noise levels would not exceed the City’s daytime and nighttime exterior noise standards of 65 dBA and 55 dBA for residential uses, respectively. In addition, these noise levels would not exceed the City’s daytime and nighttime exterior noise standard of 80 dBA and 70 dBA for commercial uses, respectively. Therefore, no noise impacts from on‐site HVAC equipme
nt would occur, and no noise reduction measures are required.

Table Q: HVAC Noise Levels
Land Use  Direction
Reference
Noise
Level1
(dBA Leq)
Reference
Distance
(ft)
HVAC
Equipment
to Property Line
Distance (ft)
Distance
Attenuation
(dBA)
Shielding2
(dBA)
Noise
Level
(dBA Leq)
Commercial  North  56.2  50  85  4.6  8  43.6
Commercial  East  56.2  50  50  0.0  8  48.2
Commercial  South  56.2  50  45 ‐ 0.9  8  49.1
Residential  West  56.2  50  170  10.6  8  37.6
Source: Compiled by LSA Associates, Inc. (2022).
1  The composite noise level of 40 HVAC units. The detailed composite noise level calculations are provided in. Attachment E 2  The roofline and high parapet would provide a minimum noise reduction of 8 dBA. dBA = A‐weighted decibels
ft = foot/feet
HVAC = heating, ventilation, and air conditioning
Leq = equivalent continuous sound level

Long‐Term Ground‐Borne Noise and Vibration
The proposed project would not generate vibration levels. In addition, vibration levels generated from project‐related traffic on the adjacent roadway (Bouquet Canyon Road) are unusual for on‐road vehicles because the rubber tires and suspension systems of on‐road vehicles provide vibration isolation. Therefore, no long‐term vibration impacts from long‐term operations of the project would occur, and no vibration re
duction measures are required.

STANDARD CONDITIONS AND REGULATORY COMPLIANCE
Short‐Term Construction Noise Impacts
The following measures would further minimize construction noise:
 The construction contractor shall limit construction activities to between the hours of 7:00 a.m. and 7:00 p.m. Monday through Friday and between the hours of 8:00 a.m. and 6:00 p.m. on Saturday. No work shall be performed outside of these hours or on Sundays, Ne w Year’s Day, Independence Day, Thanksgiving, Christmas, Memorial Day, and Labor Day.  During all project site excavation and grading, the project contractors shall equip all construction equipment, fixed or mobile, with properly operating and maintained mufflers consistent with manufacturers’ standards.
 The construction contractor shall locate equipment staging in areas that will create the greate st distance between construction‐related noise sources and most noise‐sensitive receptors nearest the project site during all project construction.

10/9/23 «P:\HAV2001\Noise\Product\Noise Memo_20231009.docx» 32  The construction contractor shall place all stationary construction equipment so that the emitted noise is directed away from the sensitive receptors nearest the project site.

Traffic Noise Impacts
The following measure is required to comply with Policy N3.1.9 in the Noise Element of the General Plan:
 Notification shall be provided to all potential buyers or renters of the residential dwelling units of noise sources in the area, new noise sources that may occur in the future, commercial uses that may generate noise in excess of lev
els for residential uses, commercial uses may change
over time, and noise levels and frequency of noise events may change along with the change in commercial use.

REDUCTION MEASURES
Short‐Term Construction Noise Impacts
No noise reduction measures are required.

Short‐Term Construction Vibration Impacts
No vibration reduction measures are required.

Aircraft Noise Impacts
No noise reduction measures are required.

Traffic Noise Impacts
The following on‐site noise reduction measures would be required for the proposed project.  All residential dwelling units and the rooftop terrace shall have a balcony barrier or rooftop terrace barrier with a minimum height of 6 ft.
 The exterior wall assembly shall meet or exceed the assumptions above.  All windows and glass doors in
the living rooms of the corner units on the east side of the project site facing Bouquet Canyon Road shall have a minimum STC rating of 31.  All windows and glass doors in other habitable rooms (i.e., bedrooms and living rooms) shall have a minimum ST C rating of 28.

Long‐Term Stationary Noise Impacts
No noise reduction measures are required.

Long‐Term Vibration Impacts
No vibration reduction measures are required.

Attachments:  A – References
B – FHWA Traffic Noise Model Printouts
C – Detailed Exterior Noise Calculations
D – INSUL Printouts
E – Composite HVAC Noise Calculations
N OISE   AND   V IBRATION   I MPACT   A NALYSIS
A UGUST   2023
P ROMENADE   F LATS   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Noise\Product\Noise Memo_20231009.docx «10/09/23» ATTACHMENT A

REFERENCES
City of Santa Clarita. 2011a. General Plan, Circulation Element. June. Website: https://www.code publishing.com/CA/SantaClarita/html/SantaClaritaGP/4%20‐%20Circulation%20Element.pdf (accessed August 2023).
_____. 2011b. General Plan, Noise Element. June. Website: https://www.codepublishing.com/ CA/SantaClarita/html/SantaClaritaGP/5%20‐%20Noise%20Element.pdf (accessed August 2023).
_____.  2013. City of Santa Clarita Traffic Flow Map. April. Website: https://www.santa‐clarita.com/ home/showpublisheddocument?id=7621 (accessed May 2022). _____. 2023. Municipal Code. Apri l 25.

Federal Highway Administration (FHWA). 1977. Highway Traffic Noise Prediction Model, FHWA‐RD‐77‐108.
_____. 2006. Highway Construction Noise Handbook. Roadway Construction Noise Model, FHWA‐HEP‐06‐015. DOT‐VNTSC‐FHWA‐06‐02. NTIS No. PB2006‐109012. August.

Federal Transit Administration (FTA). 2018. Transit Noise and Vibration Impact  Assessment Manual.

FTA Report No. 0123. September. Website: https://www.transit.dot.gov/sites/fta.dot.gov/ files/docs/research‐innovation/118131/transit‐noise‐and‐vibration‐impact‐assessment‐ manual‐fta‐report‐no‐0123_0.pdf (accessed August 2023).

Harris, Cyril M., editor. 1991. Handbook of Acoustical Measurements and Noise Control, Third Edition.

Institute of Transportation Engineers (ITE). 2021. Trip Generation Manual. 11th ed.

Los Angeles County Airport Land Use Commission (ALUC). 2004. Los Angeles County Airport Land Use Plan. December 1.

United States Environmental Protection Agency (EPA). 1978. Protective Noise Levels, Condensed Version of EPA Levels Document. EPA 550/9‐79‐100. November.

N OISE   AND   V IBRATION   I MPACT   A NALYSIS
A UGUST   2023
P ROMENADE   F LATS   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Noise\Product\Noise Memo_20231009.docx «10/09/23» ATTACHMENT B

FHWA TRAFFIC NOISE MODEL PRINTOUTS
TABLE Existing-01

FHWA ROADWAY NOISE LEVEL ANALYSIS

RUN DATE: 05/28/2021
ROADWAY SEGMENT: Bouquet Canyon Road
NOTES: Santa Clarita Plaza - Existing
______________________________________________________________________

* * ASSUMPTIONS * *

AVERAGE DAILY TRAFFIC: 37650 SPEED (MPH): 45 GRADE: .5

TRAFFIC DISTRIBUTION PERCENTAGES

DAY EVENING NIGHT
--- ------- -----
AUTOS

75.51 12.57 9.34

M-TRUCKS

1.56 0.09 0.19

H-TRUCKS

0.64 0.02 0.08

ACTIVE HALF-WIDTH (FT): 28 SITE CHARACTERISTICS: HARD

______________________________________________________________________

* * CALCULATED NOISE LEVELS * *

CNEL AT 50 FT FROM NEAR TRAVEL LANE CENTERLINE (dB) = 71.73

DISTANCE (FEET) FROM ROADWAY CENTERLINE TO CNEL
70 CNEL 65 CNEL 60 CNEL 55 CNEL
------- ------- ------- -------
112.0 343.9 1084.3 3427.5

______________________________________________________________________

TABLE Future-01

FHWA ROADWAY NOISE LEVEL ANALYSIS

RUN DATE: 05/28/2021
ROADWAY SEGMENT: Bouquet Canyon Road
NOTES: Santa Clarita Plaza - Future
______________________________________________________________________

* * ASSUMPTIONS * *

AVERAGE DAILY TRAFFIC: 45000 SPEED (MPH): 45 GRADE: .5

TRAFFIC DISTRIBUTION PERCENTAGES

DAY EVENING NIGHT
--- ------- -----
AUTOS

75.51 12.57 9.34

M-TRUCKS

1.56 0.09 0.19

H-TRUCKS

0.64 0.02 0.08

ACTIVE HALF-WIDTH (FT): 28 SITE CHARACTERISTICS: HARD

______________________________________________________________________

* * CALCULATED NOISE LEVELS * *

CNEL AT 50 FT FROM NEAR TRAVEL LANE CENTERLINE (dB) = 72.50

DISTANCE (FEET) FROM ROADWAY CENTERLINE TO CNEL
70 CNEL 65 CNEL 60 CNEL 55 CNEL
------- ------- ------- -------
132.6 410.7 1295.8 4096.5

______________________________________________________________________

N OISE   AND   V IBRATION   I MPACT   A NALYSIS
A UGUST   2023
P ROMENADE   F LATS   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Noise\Product\Noise Memo_20231009.docx «10/09/23» ATTACHMENT C

DETAILED EXTERIOR NOISE CALCULATIONS
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Roadway
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
(dBA CNEL)
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Rail
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
(dBA CNEL)
R‐1 65 344 222 5 63 64.2 50 311 6 46 63
R‐2 65 344 386 3 61 64.2 50 476 4 46 61
Table C‐1: Existing Ground Floor Exterior Noise Levels (Calibration) Source: Compiled by LSA Associates, Inc. (2021).

CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
ft = foot/feet
Receptor No.

Bouquet Canyon Road Metrolink
Composite
Noise Level
(dBA CNEL)
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Roadway
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
with
Shielding
(dBA CNEL)
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Rail
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
with
Shielding
(dBA CNEL)
R‐1 65 344 222 0 68 64.2 50 311 0 52 68
R‐2 65 344 386 0 64 64.2 50 476 0 50 64
Table C‐2:  Existing Upper Floor Exterior Noise Levels
ft = foot/feet
Receptor No.

Composite
Noise Level
(dBA CNEL)
Source: Compiled by LSA Associates, Inc. (2021).

CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
Bouquet Canyon Road Metrolink
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Roadway
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
with
Shielding
(dBA CNEL)
Reference
Noise Level
(dBA CNEL)
Reference
Distance (ft)
Rail
Centerline to
Receptor
Distance (ft)
Shielding
(dBA)
Noise Level
with
Shielding
(dBA CNEL)
R‐1 65 411 222 0 69 64.2 50 311 0 52 69
R‐2 65 411 386 0 65 64.2 50 476 0 50 65
Table C‐3: Future Upper Floor Exterior Noise Levels
Note: The Predicted Future Noise Level was calculated by adding the Future Increase in Noise Level (Future Modeled Noise Level minus Existing Modeled Noise Level) to CNEL = Community Noise Equivalent Level
dBA = A‐weighted decibels
ft = foot/feet
Receptor No.

Composite
Noise Level
(dBA CNEL)
Bouquet Canyon Road Metrolink
Source: Compiled by LSA Associates, In c. (2021).

N OISE   AND   V IBRATION   I MPACT   A NALYSIS
A UGUST   2023
P ROMENADE   F LATS   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Noise\Product\Noise Memo_20231009.docx «10/09/23» ATTACHMENT D

INSUL MODEL RESULTS PRINTOUTS

N OISE   AND   V IBRATION   I MPACT   A NALYSIS
A UGUST   2023
P ROMENADE   F LATS   P ROJECT
S ANTA   C LARITA ,   C ALIFORNIA

P:\HAV2001\Noise\Product\Noise Memo_20231009.docx «10/09/23» ATTACHMENT E

COMPOSITE HVAC NOISE CALCULATIONS
Area
Served Unit Space
Model
No. Capacity
Sound Power
Level (SWL)
Sound Pressure
Level (SPL dBA)
SPL
Reference
Distance (ft)
Noise Level
at 50 ft
(dBA) Energy
1‐1 Tenant #101 36 77 45.4 50 45.4 34673.7
1‐2 Tenant #102 36 77 45.4 50 45.4 34673.7
1‐3 Tenant #103 24 76 44.4 50 44.4 27542.3
1‐4 Tenant #104 36 77 45.4 50 45.4 34673.7
1‐5 Tenant #105 36 77 45.4 50 45.4 34673.7
1‐6 Tenant #106 48 79 47.4 50 47.4 54954.1
1‐7 Tenant #107 36 77 45.4 50 45.4 34673.7
2‐1 Unit #1 24 n/a 60 3.28 36.3 4265.8
2‐2 Unit #2 24 n/a 60 3.28 36.3 4265.8
2‐3 Unit #3 24 n/a 60 3.28 36.3 4265.8
2‐4 Unit #4 24 n/a 60 3.28 36.3 4265.8
2‐5 Unit #5  38MBRQ 36 n/a 63 3.28 39.3 8511.4
2‐6 Unit #6 24 n/a 60 3.28 36.3 4265.8
2‐7 Unit #7 24 n/a 60 3.28 36.3 4265.8
2‐8 Unit #8 24 n/a 60 3.28 36.3 4265.8
2‐9 Unit #9 24 n/a 60 3.28 36.3 4265.8
2‐10 Unit #10  38MBRQ 36 n/a 63 3.28 39.3 8511.4
3‐1 Unit #11 24 n/a 60 3.28 36.3 4265.8
3‐2 Unit #12 24 n/a 60 3.28 36.3 4265.8
3‐3 Unit #13 24 n/a 60 3.28 36.3 4265.8
3‐4 Unit #14 24 n/a 60 3.28 36.3 4265.8
3‐5 Unit #15  38MBRQ 36 n/a 63 3.28 39.3 8511.4
3‐6 Unit #16 24 n/a 60 3.28 36.3 4265.8
3‐7 Unit #17 24 n/a 60 3.28 36.3 4265.8
3‐8 Unit #18 24 n/a 60 3.28 36.3 4265.8
3‐9 Unit #19 24 n/a 60 3.28 36.3 4265.8
3‐10 Unit #20  38MBRQ 36 n/a 63 3.28 39.3 8511.4
4‐1 Unit #21 24 n/a 60 3.28 36.3 4265.8
4‐2 Unit #22 24 n/a 60 3.28 36.3 4265.8
4‐3 Unit
#23 24 n/a 60 3.28 36.3 4265.8
4‐4 Unit #24 24 n/a 60 3.28 36.3 4265.8
4‐5 Unit #25 24 n/a 60 3.28 36.3 4265.8
4‐6 Unit #26 24 n/a 60 3.28 36.3 4265.8
4‐7 Unit #27 24 n/a 60 3.28 36.3 4265.8
4‐8 Unit #28 24 n/a 60 3.28 36.3 4265.8
4‐9 Unit #29 24 n/a 60 3.28 36.3 4265.8
4‐10 Unit #30 24 n/a 60 3.28 36.3 4265.8
4‐11 Gym  Room 24 n/a 60 3.28 36.3 4265.8
4‐12 Rec  Room 24 n/a 60 3.28 36.3 4265.8
4‐13 Lobby? 24 n/a 60 3.28 36.3 4265.8
Combined Leq at 50 ft  56.2
HVAC Equipment and Noise Level Calculations
Retail
Residential
25HCE4
38MAQB
38MAQB
38MAQB
38MAQB
38MAQB
November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Attachment C
Air Quality Study

CARLSBAD
CLOVIS
IRVINE
LOS ANGELES
PALM SPRINGS
POINT RICHMOND

RIVERSIDE

ROSEVILLE
SAN LUIS OBISPO
3210 El Camino Real, Suite 100, Irvine, California 92602     949.553.0666     www.lsa.net

MEMORANDUM
DATE:  August 23, 2023
TO:  Robert Neman, Harvard 826 Property LLC
FROM:  Ronald Brugger, Senior Air Quality Specialist
SUBJECT:  Air Quality and Greenhouse Gas Emissions Impact Analysis Memorandum for the proposed Promenade Flats Project in Santa Clarita, California

INTRODUCTION
This air quality and greenhouse gas (GHG) emissions impact analysis for the proposed Promenade Flats Project at 26135 Bouquet Canyon Road in Santa Clarita, California (project) has been prepared using methods and assumptions recommended in the South Coast Air Quality Management District’s (SCAQMD) CEQA Air Quality Handbook (SCAQMD 1993). This analysis includes a description of existing re
gulatory framework, an assessment of project operational air quality emissions, and an assessment of GHG emissions. Measures to reduce or eliminate significant impacts are identified, where appropriate. All references cited in the memorandum are included in Attachment A.

Project Location
The project site is located along the west side of Bouquet Canyon Road, north of Magic Mountain Parkway and south of Cinema Drive at (Assessor’s Parcel Number 2811‐003‐018), 26135 Bouquet Canyon Road in the community of Valencia. The project site has a Mixed‐Use Corridor (MXC) zoning designation. Figure 1 shows the project location (all figures are in Attachme nt B).

Project Description
The proposed project would remove a portion of the existing parking lot to accommodate a new four‐story, mixed‐use building on 1.2 acres. The proposed project would include a total of 15,741.50 square feet (sf) of commercial use consisting of a 7,266.10 sf first‐floor retail space, a 3,027.40 sf rooftop yoga studio, and the exi
sting 5,448 sf International House of Pancakes (IHOP) restaurant. In addition to the new commercial uses, the proposed building would include four live/work units and 26 one‐bedroom units on floors two through four. A new 14,359 sf (0.33 acre) parking lot would be constructed on an adjacent vacant parcel to offset the parkin g that would be removed as part of the project. Construction of the proposed project would start in January 2024 and would be completed in approximately 12 months. Figure 2 shows the site plan. Project traffic is described in the Transportation Memorandum (LSA 2022).

Land Uses in the Project Vicinity
Land uses surrounding the proposed building include the Las Flores Apartments and the Global Prep Academy to the west of the project site. The new parking lot would be just south of the Las Flores

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 2 Apartments. Otherwise, there are commercial uses to the north, east, and south. Bouquet Canyon Road and the Metrolink rail are located east of the project.

Climate/Meteorology
Air quality in the planning area is affected not only by various emission sources (e.g., mobile and industry) but also by atmospheric conditions (e.g., wind speed, wind direction, temperature, and rainfall). The combination of topography, low mixing height, abundant sunshine, and emissions from the second‐largest urban area in the United States gives the South Coast Air Basin (Basin) some  of the worst air pollution problems in the nation.

The Santa Clarita Valley is surrounded by the Santa Susana and San Gabriel mountain ranges on the south, east and west, and the Sierra Pelona Mountains on the north. The Valley lies in a transitional microcli
matic zone of the Basin between the “valley marginal” and “high desert” climate types.

Situated far enough from the ocean to escape coastal influences, the Valley’s climate is generally mild with hot summers and sunny, warm winters. Average annual precipitation is about 13 inches, usually received between November and March, alth ough some mountain areas south of the Valley may receive up to 24 inches of precipitation per year.

However, transport of the pollution that is emitted in the southern parts of the Basin and in the San Fernando Valley gets transported by onshore winds up through the Newhall Pass up toward th e Santa Clarita Valley results in high levels of ground‐level ozone every summer. Though Santa Clarita sits between two of the largest pollution areas, Los Angeles and Bakersfield, most of the air quality readings for the Santa Clarita Valley range between 58 to 78 percent below the state average.

REGULATORY FRAMEWORK
Air quality and GHG standards and the regulatory framework are discussed below.

Federal Regulations
Pursuant to the federal Clean Air Act (CAA) of 1970, the United States Environmental Protection Agency (EPA) established the National Ambient Air Quality Standards (NAAQS). The NAAQS were established for six major pollutants, termed “criteria” pollutants. Criteria pollutants are defined as those pollutants for which the federal and State governments have established AAQS, or cri teria, for outdoor concentrations to protect public health.

The EPA has designated the Southern California Association of Governments (SCAG) as the Metropolitan Planning Organization responsible for ensuring compliance with the requirements of the CAA for the Basin.

The United States has historically had a voluntary approach to reducing GHG emissions; however, on April 2, 2007, the United Stat
es Supreme Court ruled that the EPA has the authority to regulate carbon dioxide (CO2) emissions under the CAA. The Supreme Court ruled that GHGs fit within the CAA’s definition of a pollutant and that the EPA did not have a valid rationale for not regulating GHGs. In December 2009, the EPA issued an endangerment finding for GHGs under the CAA.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 3 On December 7, 2009, the EPA Administrator signed a final action under the CAA, finding that six GHGs (i.e., CO2, methane [CH4], nitrous oxide [N2O], hydrofluorocarbons [HFCs], perfluorocarbons [PFCs], and sulfur hexafluoride [SF6]) constitute a threat to public health and welfare and that the combined emissions from motor vehicles cause and contribute to global climate change (GCC).

Multistate
The Western Regional Climate Action Initiative
The Western Regional Climate Action Initiative is a partnership among seven states including California and four Canadian provinces to implement a regional, economy‐wide cap‐and‐trade system to reduce global warming pollution. The Western Regional Climate Action Initiative will cap GHG emissions from the region’s electr icity, industrial, and transportation sectors with the goal to reduce the heat trapping emissions that cause global warming to 15% below 2005 levels by 2020.

When the Western Regional Climate Action Initiative adopted this goal in 2007, it estimated this would require 2007 levels to be reduced worldwide between 50% and 85% by 2050. California is working closely with the other states and provinces to design a regional GHG re duction program
that includes a cap‐and‐trade approach.

The California Air Resources Board (CARB) has implemented a cap‐and‐trade program that is also intended to link California and the other member st ates and provinces. The cap‐and‐trade regulation, which is a key element of California’s climate plan, took effect in January 2012 and compliance obligation began in January 2013. The cap‐and‐trade program sets a statewide limit on sources responsible for 85% of California’s GHG emissions and establishes a pric e signal needed to drive long‐term investment in cleaner fuels and more efficient use of energy. As of January 1, 2014, California’s cap‐and‐trade program is linked to Quebec’s pursuant to the Agreement Between the CARB and the Gouvernement du Québec Concerning the Harmonization and Integration of Cap‐ and‐ Trade Programs Reducing Greenhouse Gas Emissions, in accordance with the direction in CARB Board Resolution 13‐7 (CARB 2013). As of January 1, 2018, California’s cap‐and‐trade program and Québec’s program linked with Ontario’s cap‐and‐trade program. However, on July 3, 2018, the Ontario government revoked its cap‐and‐trade regulation. With On tario’s withdrawal from the linked program, California and Québec will work together to ensure that the environmental integrity and stringency of the cap‐and‐trade program/market is sustained (CARB n.d.‐a).

The program is designed to provide covered entities the flexibility to seek out and implement the lowest‐
cost options to reduce emissions. The first phase of the cap‐and‐trade regulation included electricity generated in and imported into California, large combustion sources (i.e., generally those emitting more than 25,000 metric tons [MT] of carbon dioxide equivalent [CO2e] per year), and certain industrial sectors. The second phase added providers of transportation fuels and other combustion fuels (e.g., natural gas, propane) to the cap‐and‐trade program. The regulation requires that emissions generated by these facilities and combustion of fuels be reduced over time under a declining cap.

Pacific Coast Action Plan on Climate and  Energy
On October 28, 2013, the Governors of California, Oregon, and Washington and the Premier of British Columbia signed a clean energy pact, known as the Pacific Coast Action Plan on Climate and Energy. Although the Pacific Coast Action Plan does not impose legally enforceable obligat ions and

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 4 lacks a specific schedule for implementation, the pact sets out a number of goals and aspirational measures. The Pacific Coast Action Plan calls upon each of the parties to undertake a number of measures to address the use of carbon‐based fuels in the transportation sector, including the adoption or maintenance of low ‐carbon fuel standards, the development of targets and action plans in order to encourage public and private investment in low‐carbon commercial fleets that use alternative fields, and the expansion of the sale of zero‐emissions vehicles to a goal of 10% of new vehicle purchases by 2016.

California Air Resources Board
In 1967, the State Legislature passed the Mulford‐Carrell Act, which combined two Department of Health bureaus (i.e., the Bureau of Air Sanitation and the Motor Vehicle Pollution Control Board) to establish CARB. Since its formation, CARB has worked with the public, the business sector, and local governments to find solutions to the Stat e’s  air pollution problems. California adopted the California Clean Air Act (CCAA) in 1988. CARB administers the California Ambient Air Quality Standards (CAAQS) for the 10 air pollutants designated in the CCAA. These 10 State air pollutants are the 6 criteria pollutants designated by the federal CAA as well as 4 others: visibility‐reduci ng particulates, hydrogen sulfide (H2S), sulfates, and vinyl chloride.

The California Global Warming Solutions Act of 2006, widely known as Assembly Bill (AB) 32, requires CARB to develop and enforce regulations for the reporting and verification of statewide GHG emissions. CARB was directed to set a statewide GHG emissions limit and set a timeline for adopting a scoping plan for
achieving GHG reductions in a technologically and economically feasible manner.

The heart of the bill is the requirement that statewide GHG emissions be reduced to 1990 levels by 2020. The bill requires CARB to adopt rules and regulations in an open public process to achieve the maximum
technologically feasible and cost‐effective GHG reductions.

In 2016, the Legislature passed and Governor Jerry Brown signed, Senate Bill (SB) 32 and AB 197.

SB 32 affirms the importance of addressing climate change by codifying into statute the GHG emissions reductions target of at least 40 percent below 1990 levels by 2030 contained in Go vernor Brown’s April 2015 Executive Order (EO) B‐30‐15. SB 32 builds on AB 32 and keeps California on the path toward achieving the State’s 2050 objective of reducing emissions to 80 percent below 1990 levels, consistent with an Intergovernmental Panel on Climate Change (IPCC) analysis of the emissions trajectory that would stabilize atmospheric GHG con centrations at 450 parts per million
(ppm) CO2e and reduce the likelihood of catastrophic impacts from climate change (IPCC 2023). The companion bill to SB 32, AB 197, provides additional direction to CARB related to the adoption of strategies to reduce GHG emissions.

CARB adopted the 2022 Scoping Plan Update on December 15, 2022. The 2022 Scoping Plan Update assesses progress toward the statutory
2030 target, while laying out a path to achieving carbon neutrality no later than 2045. The 2022 Scoping Plan Update focuses on outcomes needed to achieve carbon neutrality by assessing paths for clean technology, energy deployment, natural and working lands, and others and is designed to meet th e State’s long‐term climate objectives and support a range of economic, environmental, energy security, environmental justice, and public health priorities. Appendix D of the Scoping Plan includes information about project attributes that

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 5 would reduce operational GHG emissions and accommodate growth in a manner consistent with State GHG reduction and equity prioritization goals.

Although the 2022 Scoping Plan does not impose any specific mandates or policies that specifically apply to individual development projects such as the proposed project, the Scoping Plan encourages local municipalities to upd ate building codes and establish sustainable development practices for accommodating future growth. Key policies that involve the residential and commercial building sectors that are indirectly applicable to the proposed Project include the implementation of SB 275 (promoting infill development and high‐density housing in high quality transit areas), implementing green building practices (i.e., the California Gre
en Building Standards Code), energy efficiency and
water conservation policies, and waste diversion efforts.

Senate Bill 97 and CEQA Guidelines
In August 2007, the Legislature adopted SB 97, requiring the Office of Planning and Research (OPR) to prepare and transmit new California Environmental Quality Act (CEQA) gui delines for the mitigation of GHG emissions or the effects of GHG emissions to the California Natural Resources Agency. OPR submitted its proposed guidelines to the Secretary for Natural Resources on April 13, 2009, and the CEQA Guidelines amendments were adopted on December 30, 2009 and became effective on March 18, 2010.

The CE
QA Guidelines amendments do not specify a threshold of significance for GHG emissions or prescribe assessment methodologies or specific mitigation measures. Instead, the amendments encourage lead agencies to consider many factors in performing a CEQA analysis but rely on the lead agencies in making their own significance deter minations based upon substantial evidence. The CEQA Guidelines amendments also encourage public agencies to make use of programmatic mitigation plans and programs from which to tier when they perform individual project analyses.

The CEQA Guidelines amendments require a lead agency to make a good‐faith effort based on the extent possible on scie ntific and factual data to describe, calculate or estimate the amount of GHG emissions resulting from a project. The CEQA Guidelines amendments give discretion to the lead agency whether to (1) use a model or methodology to quantify GHG emissions resulting from a project and which model or methodology to use and/or (2) rely on a qualitati ve analysis or performance‐based standards. The California Natural Resources Agency is required to periodically update the guidelines to incorporate new information or criteria established by CARB pursuant to AB 32.

California Green Building Standards
The California Green Building Standards Code, which is Part 11 of the California Code of Regu lations, is commonly referred to as the CALGreen Code. The first edition of the CALGreen Code was released in 2008 and contained only voluntary standards. The 2022 CALGreen Code was updated in 2022, became effective on January 1, 2023, and applies to non‐residential and r esidential developments.

The CALGreen Code contains requirements for construction site selection, stormwater control during construction, construction waste reduction, indoor water use reduction, material selection, natural resource conservation, site irrigation conservation, and more. The CALGreen Code provides for design options allowing the designer to determine how best to achieve compliance for a given site or building condition. The CAL
Green Code also requires building commissioning, which is a

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 6 process for the verification that all building systems, such as heating and cooling equipment and lighting systems, function at their maximum efficiency. The proposed project would be subject to the 2022 CALGreen Code that became effective on January 1, 2023. Requirements of the 2022 CALGreen Code that are applicable to the proposed project inc lude the following:

4.106.4  Electric Vehicle (EV) charging. New construction shall comply with Section 4.106.4.1 or 4.106.4.2 to facilitate future installation and use of EV chargers. Electric vehicle supply equipment (EVSE) shall be installed in accordance with the California Electrical Code, Article 625.

4.303.1  Water Conserving Plumbing Fixtures and Fittings. Al l water fixtures shall comply with the California Code of Regulations, Title 20, (Appliance Efficiency Regulations), Section 1605.1(h)(4) and Section 1605.3(h)(4)(A).

4.304.1  Outdoor Potable Water Use in Landscape Areas. Residential developments shall comply with a local water efficient landscape ordinance or the current California Department of Water Resources’ Model Water Efficient Landscape  Ordinance (MWELO), whichever is more stringent.

4.408.1  Construction Waste Management. Recycle and/or salvage for reuse a minimum of 65 percent of the nonhazardous construction and demolition waste in accordance with Section 5.408.1.1, 5.408.1.2, or 5.408.1.3, or meet the City’s construction and demolition waste management ordinance, whichever is more stringent.

4.410.2  Recycling by Occupan
ts. Where 5 or more multifamily units are constructed on a building site, provide readily accessible areas that serve all buildings on the site and are identified for the depositing, storage, and collection of non‐hazardous materials for recycling, including (at a minimum) paper, corrugated cardboard, glass,  plastics, organic waste, and metals, or meet the City’s local recycling ordinance, whichever is more restrictive.

Regional Air Quality Planning Framework
SCAG is a council of governments for Imperial, Los Angeles, Orange, Riverside, San Bernardino, and Ventura Counties. SCAG is a regional planning agency and a forum for regional issues relating to transportation, the economy and community development, and the environment. Although SCAG is not an air quality management agency, it is responsible for devel oping transportation, land use, and energy conservation measures that affect air quality.

On September 3, 2020, the Regional Council of SCAG adopted Connect SoCal, also known as the 2020–2045 Regional Transportation Plan/Sustainable Communities Strategy: A Plan for Mobility, Accessibility, Sustainability, and High Quality of Life (a.k.a., 2020–2045 RTP/SCS). The 2020–2 045 RTP/SCS is a long‐range visioning plan that balances future mobility and housing needs with economic, environmental and public health goals. Connect SoCal embodies a collective vision for the region’s future and is developed with input from local governments, county transportation commissions (CTCs), tribal governments, non‐profit organizations, businesses and local stakeholders within th
e counties of Imperial, Los Angeles, Orange, Riverside, San Bernardino and Ventura.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 7 South Coast Air Quality Management District
The SCAQMD is the agency principally responsible for comprehensive air pollution control in the Basin. To that end, the SCAQMD, a regional agency, works directly with SCAG, county transportation commissions and local governments, and cooperates actively with State and federal government agencies. The SCAQMD develops air  quality‐related rules and regulations, establishes permitting requirements, inspects emissions sources, and provides regulatory enforcement through such measures as educational programs or fines, when necessary.

Regional Air Quality Management Plan
SCAQMD and SCAG are responsible for formulating and implementing the Air Quality Management Plan (AQMP) for the Basin. The main purpose of an AQ MP is to bring the area into compliance with federal and State air quality standards. SCAQMD prepares a new AQMP every 3 years, updating the previous plan and a 20‐year horizon.

The latest plan is the 2022 AQMP (SCAQMD 2022), adopted December 2, 2022. On October 1, 2015, the EPA
strengthened the NAAQS for ground‐level ozone, lowering the primary and secondary ozone standard levels to 70 parts per billion (ppb). The Basin is classified as an “extreme” nonattainment area. The 2022 AQMP was developed to address the requirements for meeting this standard. SCAQMD adopts rules and regulations to i mplement portions of the AQMP. Several of these rules may apply to project construction or operation. For example, SCAQMD Rule 403 requires the implementation of the best‐available fugitive dust control measure during active construction periods capable of generating fugitive dust emissions from on‐site earth‐moving activities, construction/d
emolition activities, and construction equipment travel on paved and unpaved roads.

Although SCAQMD is responsible for regional air quality planning efforts, it does not have the authority to directly regulate the air quality issues associated with new development projects within the Basin, such as the proposed project. Instead, SCAQMD published the CEQA Air Quality H andbook (SCAQMD 1993) to assist lead agencies, as well as consultants, project proponents, and other interested parties in evaluating potential air quality impacts of projects proposed in the Basin. The CEQA Air Quality Handbook provides standards, methodologies, and procedures for conducting air quality analyses in Environmental Impact Report s and was used extensively in the preparation of this analysis. SCAQMD is currently in the process of replacing the CEQA Air Quality Handbook (1993) with the Air Quality Analysis Guidance Handbook (SCAQMD n.d.).

To assist the CEQA practitioner in conducting an air quality analysis in the interim while the replacement Air Quality Analysis Guidance Han
dbook is being prepared, supplemental guidance/
information is provided on the SCAQMD website and includes (1) on‐road vehicle emission factors, (2) background carbon monoxide (CO) concentrations, (3) localized significance thresholds (LSTs), (4) mitigation measures and control efficiencies, (5) mobile‐source toxics analysis, (6) off‐road mobile‐ source emission factors, (7) particulat
e matter less than 2.5 microns in size [PM2.5] significance thresholds and calculation methodology, and (8) updated SCAQMD Air Quality Significance Thresholds. SCAQMD also recommends using approved models to calculate emissions from land use projects, such as the California Emissions Estimator Model (CalEEMod). These recommendations were followed in the preparation of this analysis.

The following SCAQMD rules and regulations would apply to th e proposed project:

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 8  SCAQMD Rule 403 (SCAQMD 2005) requires projects to incorporate fugitive dust control measures.
 SCAQMD Rule 1113 (SCAQMD 2016) limits the volatile organic compound (VOC) content of architectural coatings.

Local Regulations
City of Santa Clarita General Plan
Local jurisdictions, such as the City of Santa Clarita, have the authority and responsibility to reduce air pollution through their police power and decision‐making authority. Specifically, the City is responsible for the assessment and mitigation of air emissions resulting from its land use decisions.

The City is also responsible for impl
ementation of the transportation control measures in the AQMP, such as bus turnouts, energy‐efficient streetlights, and synchronized traffic signals.

The Conservation and Open Space Element of the City of Santa Clarita General Plan has identified goals, objectives, and policies aimed at greenhouse gas reduction at the citywid e level (City of Santa Clarita 2011).

City of Santa Clarita Climate Action Plan
The City developed and published its Final Climate Action Plan (CAP) in August 2012. The CAP, part of the General Plan, serves as a component of the general plan document for the City to address GHG
emissions. Using the goals, objectives, and policies of the General Plan as a starting point, the CAP identifies mitigation measures that can be quantified and translated into significant reductions in the GHG emissions by the year 2020. Measures identified in the City’s CAP will not only meet but exceed the State’s Glob al Warming Solutions Act of 2006 (AB 32) GHG emission reduction mandate (City of Santa Clarita 2012).

The CAP defines a local threshold of significance for GHG emissions for project level submittals that trigger review by CEQA. Because goals, objectives, and policies approved under the General Plan are forecast to meet the GHG emission reduction target
s mandated by AB 32, development projects
that are able to demonstrate consistency with the General Plan and zoning ordinance will by association demonstrate consistency with the CAP. However, because the CAP is only certified through 2020 it is not utilized for CEQA streamlining in this analysis.

THRESHOLDS OF SIGNIFICANCE
Certain air districts (e.g., SCAQMD) have created guidelines and requirements to conduct air quality analyses. SCAQMD’s current guidelines, the CEQA Air Quality Handbook (SCAQMD 1993) with associated updates, were followed in this assessment of air quality and climate impacts for the proposed project.

Based on the State CEQA Guidelines, Appendix G (Public Resource s Code Sections 15000–15387), a project would normally be considered to have a significant effect on air quality if the project would violate any CAAQS, contribute substantially to an existing air quality violation, expose sensitive receptors to substantial pollutants concentrations, or conflict with adopted environmental plans and goals of the community in which it is located.

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SCAQMD has established daily emissions thresholds for construction and operation of a proposed project in the Basin. The emissions thresholds were established based on the attainment status of the Basin with regard to air quality standards for specific criteria pollutants. Because the concentration standards were set at a level that protects public healt h  with an adequate margin of safety (SCAQMD 2022), these emissions thresholds are regarded as conservative and would overstate an individual project’s contribution to health risks. Table 1 lists the CEQA significance thresholds for construction and operational emissions established for the Basin.

Table 1: Regional Thresholds for Construction and Operational Emissions Emissions Source  Pollutant Emissions Thresholds (lbs/day) VOCs  NOX  CO  PM10  PM2.5  SOX
Construction  75  100  550  150  55  150
Operations  55  55  550  150  55  150
Source: South Coast AQMD Air Quality Significance Thresholds (SCAQMD 2019).

CO = carbon monoxide
lbs/day = pounds per day
NOX = nitrogen oxides
PM2.5 = particulate matter less than 2.5 microns in size PM10 = particulate matter less than 10 microns in size
SCAQMD = South Coast Air Quality Management District
SOX = sulfur oxides
VOCs = volatile organic compounds

Projects in the Basin with construction‐ or operation‐related emissions that exceed any of their respective emission thresholds would be considered significant under SCAQMD guidelines. These thresholds, which SCAQMD developed and which apply throughout the Basin, apply as both project and cumulative thresholds. If a project exceeds these standards, it is considered to have a projec t‐ specific and cumulative impact.

Localized Impacts Analysis
SCAQMD published its Final Localized Significance Threshold Methodology in June 2003 and updated it in July 2008 (SCAQMD 2008), recommending that all air quality analyses include an assessment of both construction and operational impacts on the air quality of nearby sensitive receptors. LSTs represent the maximum emissions from a project site that are not expe cted to result in an exceedance of the NAAQS or the CAAQS for CO, nitrogen dioxide (NO2), particulate matter less than 10 microns in size (PM10), and PM2.5. LSTs are based on the ambient concentrations of that pollutant within the project’s Source Receptor Area (SRA) and the distance to the nearest sensitive receptor.

For this project, the appropriate SRA is the Santa Clarita Valley area (SRA 13). Sensitive receptors include residences, schools, hospitals, and similar uses that are sensitive to adverse air  quality. As described above, the closest sensitive receptors are the Las Flores Apartments, which are approximately 80 feet (ft) from the west boundary of the building construction and approximately 45 ft from the north boundary of the parking lot construction.

If the total acreage disturbed is less than or equal to 5 acres (ac) per day, then the SCAQMD’ s screening look‐up tables can be used to determine if a project has the potential to result in a significant impact. The project site is approximately 1.2 ac and the parking lot is 0.43 ac. The emissions from the larger site would be greater than the s maller and the minimum distance the LST

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Table 2 lists the emissions thresholds that apply during project construction.

Table 2: SCAQMD Localized Significance Thresholds
Emissions Source Category  Pollutant Emissions (lbs/day) NOX  CO  PM10  PM2.5
Construction (1.2 ac, 80 ft distance)  124  647  4  3
Source: Final Localized Significance Threshold Methodology (SCAQMD 2008). ac = acre
CO = carbon monoxide
ft = feet
lbs/day = pounds per day
NOX = nitrogen oxides
PM2.5 = particulate matter less than 2.5 microns in size PM10 = particulate matter less than 10 microns in size
SCAQMD = South Coast Air Quality Management District

Greenhouse Gas Emissions
State CEQA Guidelines Section 15064(b) provides that the “determination of whether a project may have a significant effect on the environment calls for careful judgment on the part of the public agency involved, based to the extent possible on scientific and factual data”, and further states that an “ironclad definition of significant eff ect is not always possible because the significance of an activity may vary with the setting.”
Appendix G of the State CEQA Guidelines includes significance thresholds for GHG emissions. A project would normally have a significant effect on the environment if it would do either of the following:
 Generate GHG  emissions, either directly or indirectly, that may have a significant impact on the environment; or
 Conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of GHGs.

Currently, there is no statewide GHG emissions threshold that has been used to determine the potential GHG emissions imp
acts of a project. Threshold methodology and thresholds are still being developed and revised by air districts in California.

As described above, the City published its Final CAP in August 2012. The CAP identified measures to support meeting the 2020 GHG emissions goals. However, since the CAP hasn’t been u pdated to be consistent with State goals detailed in SB 32, EO B‐30‐15, and EO S 3‐05 to reduce GHG emissions by 40 percent below 1990 levels by 2030, the SCAQMD threshold described below was used.

To provide guidance to local lead agencies on determining significance for GHG emissions in  their CEQA documents, SCAQMD convened a GHG CEQA Significance Threshold Working Group (Working Group) in 2008. This Working Group proposed a tiered approach for evaluating GHG emissions for development projects where SCAQMD is not the lead agency. The applicable tier for this project is Tier 3, which states that if GHG emissions are less than 3,000 MT CO2e per year, project‐level and cumulative GHG emissions would be less than significant.

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Emissions would include criteria air pollutants and GHG emissions. The sections below describe the proposed project’s consistency with applicable air quality plans, estimated project emissions, and the significance of impacts with respect to SCAQMD thresholds.

Air Quality Impacts
Consistency with Applicable Air Quality Plans
A consistency determination plays an essential role in local‐agency project review by linking local planning and unique individual projects to the air quality plans. A consistency determination fulfills the CEQA goal of fully informing local‐agency decision‐makers of the environmental costs of the project under consideratio
n at a stage early enough to ensure that air quality concerns are addressed. Only new or amended General Plan elements, Specific Plans, and significantly unique projects need to undergo a consistency review due to the air quality plan strategy being based on projections from local General Plans.

The AQMP is based on regional growth projections developed by SCAG.  The proposed project is a mixed‐use development that would not house more than 1,000 persons, occupy more than 40 ac of land, or encompass more than 650,000 sf of floor area. Thus, the proposed project would not be defined as a regionally significant project un der CEQA; therefore, it does not meet SCAG’s Intergovernmental Review criteria.

The proposed land use is consistent with the General Plan zoning. Thus, the proposed project, as analyzed, would result in air emissions that are consistent with the City’s plans. The City’s General Plan is consistent with the SCAG Regional Comprehe nsive Plan Guidelines and the SCAQMD AQMP.

Pursuant to the methodology provided in Chapter 12 of the 1993 SCAQMD CEQA Air Quality Handbook, consistency with the Basin 2016 AQMP is affirmed when a project would not increase the frequency or severity of an air quality standards violation or cause a new violation, and is consistent with the growth assumptions in the AQMP. Consistency review is presented as follows:

1. The project would result in short‐term construction and long‐term operational pollutant emissions that are all less than the CEQA significance emissions thresholds established by SCAQMD, as demonstrated above. Ther efore, the project would not result in an increase in the frequency or severity of an air quality standard violation or cause a new air quality standard violation.

2. The CEQA Air Quality Handbook (SCAQMD 1993) indicates that consistency with AQMP growth assumptions must be analyzed for new or amended  General Plan elements, Specific Plans, and significant projects. Significant projects include airports, electricity‐generating facilities, petroleum and gas refineries, designation of oil‐drilling districts, water ports, solid‐waste disposal sites, and offshore‐drilling facilities; therefore, as a small coffee shop, the proposed project is not defined as significant.

Based on the consistency an
alysis presented above, the proposed project would be consistent with the regional AQMP.

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The Basin is designated as non‐attainment for ozone (O3) and PM2.5 for federal standards and non‐ attainment for O3, PM10, and PM2.5 for State standards. The SCAQMD’s nonattainment status is attributed to the region’s development history. Past, present, and future development projects contribute to the region’s adverse air quality impacts on a cumulative basis. By its very nature, air pollution is largely a cumulative impact. No single project is sufficient in size to, by itself, result in nonattainme
nt of ambient air quality standards. Instead, a project’s individual emissions contribute to existing cumulatively significant adverse air quality impacts. If a project’s contribution to the cumulative impact is considerable, then the project’s impact on air quality would be considered significant.

In developing thresholds of significance for air pollutants, th e SCAQMD considered the emission levels for which a project’s individual emissions would be cumulatively considerable. If a project exceeds the identified significance thresholds, its emissions would be cumulatively considerable, resulting in significant adverse air quality impacts to the region’s existing air quality conditions.

Construction Emissions.  Construction activities prod uce combustion emissions from various sources (utility engines, tenant improvements, and motor vehicles transporting the construction crew). Exhaust emissions from construction activities envisioned on site would vary daily as construction activity levels change.

The construction analysis includes estimating the construction equipment that would be used during each construction activity, the hours of use for that  construction equipment, the quantities of earth and debris to be moved, and the on‐road vehicle trips (e.g., worker, soil‐hauling, and vendor trips).

The proposed demolition of the existing 10,645 sf parking lot was estimated by assuming the pavement is 145 pounds per sf, resulting in 772 tons of material to haul. The proposed earthwork for the project assumes th
e site would be balanced (no import or export needed). CalEEMod defaults are assumed for the construction activities, off‐road equipment, and on‐road construction fleet mix and trip lengths. It is expected that construction would start in January 2024 and finish in approximately 16
months. Table 3 lists the tentative project construction schedule.

Table 3: Tentative Project Construction Schedule
Phase Name  Phase Start
Date
Phase End
Date  Number of Days
Demolition  1/2/2024  1/8/2024  5
Site Preparation  1/9/2024  1/10/2024  2
Grading  1/11/2024  1/16/2024  4
Building Construction  1/17/2024  11/19/2026  220
Paving   11/20/2024  1/2/2025  32
Architectural Coating  7/9/2024  12/10/2024  110
Source: Estimated by LSA Associates, Inc. from the project information provided (August 2023).

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Table 4: Diesel Construction Equipment Used by Construction Phase Construction Phase  Off‐Road Equipment Type
Off‐Road
Equipment
Unit Amount
Hours Used
per Day  Horsepower  Load
Factor
Demolition
Concrete/Industrial Saws  1  8  33  0.73
Rubber Tired Dozers  1  8  367  0.40
Tractors/Loaders/Backhoes  3  8  84  0.37
Site Preparation
Graders  1  8  148  0.41
Rubber Tired Dozers  1  7  367  0.40
Tractors/Loaders/Backhoes  1  8  84  0.37
Grading
Graders  1  8  148  0.41
Rubber Tired Dozers  1  8  367  0.40
Tractors/Loaders/Backhoes  2  7  84  0.37
Building Construction
Cranes  1  6  367  0.29
Forklifts  1  6  82  0.20
Generator Sets  1  8  14  0.74
Tractors/Loaders/Backhoes  1  6  84  0.37
Welders  3  8  46  0.45
Paving
Cement and Mortar Mixers  1  6  10  0.56
Pavers  1  6  81  0.42
Paving Equipment  1  8  89  0.36
Rollers  1  7  36  0.38
Tractors/Loaders/Backhoes  1  8  84  0.37
Architectural Coating  Air Compressors  1  6  37  0.48
Source: Compiled by LSA Associates, Inc. using CalEEMod defaults (August 2023).

CalEEMod = California Emissions Estimator Model

The emissions rates shown in Table 5 are from the CalEEMod output tables listed as “Mitigated Construction,” even though the only measures that have been applied to the analysis are the required construction emissions control measures, or standard conditions. They are also the combination of the on‐ and off‐site emissions and the greater of s ummer and winter emissions. No exceedances of any criteria pollutants are expected. Standard measures are documented in the CalEEMod output in Attachment C.

Fugitive Dust. Fugitive dust emissions are generally associated with land clearing and exposure of soils to the air and wind, as well as cut‐and‐fill grading operations. Dust gene rated during construction varies substantially on a project‐by‐project basis, depending on the level of activity, the specific operations, and weather conditions at the time of construction.

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Construction Phase
Total Regional Pollutant Emissions (lbs/day)
VOCs  NOX  CO  SOX  Fugitive
PM10
Exhaust
PM10
Fugitive
PM2.5
Exhaust
PM2.5
Demolition  2  19  18  <1  3  1  1  1
Site Preparation  1  14  13  <1  3  1  1  1
Grading  2  16  16  <1  3  1  1  1
Building Construction  1  10  12  <1  <1  <1  <1  <1
Paving   1  5  7  <1  <1  <1  <1  <1
Architectural Coating  2  1  2  <1  <1  <1  <1  <1
Peak Daily  3  19  18  <1  4  2
SCAQMD Threshold  75  100  550  150  150  55
Exceeds Threshold?  No  No  No  No  No  No
Source: Compiled by LSA Associates, Inc. (August 2023).

Note: The application of architectural coatings was assumed to occur during both the Building Construction and Paving phases. All values shown are rounded to the nearest integer to correspond with the accuracy of the analysis.

CO = carbon monoxide
lbs/day = pounds per day
NOX = nitrogen oxides
PM2.5 = particulate matter less than 2.5 microns in size PM10 = particulate matter less than 10 microns in size
SCAQMD = South Coast Air Quality Management District
SOX = sulfur oxides
VOCs = volatile organic compounds

The construction calculations prepared for this project assumed that dust control measures (watering a minimum of two times daily consistent with SCAQMD Rule 403) would be employed to reduce emissions of fugitive dust during site grading. Furthermore, all construction would need to comply with SCAQMD Rule 403 regarding the emission of fugitive dust. Tabl e 5 lists total construction emissions (i.e., fugitive dust emissions and construction equipment exhausts) that have incorporated the following Rule 403 measures that would be implemented to significantly reduce PM10 emissions from construction:
 Water active sites at least twice daily (locations where grading is to occur shall be thoroughly watered prior to earthmoving).
 Cover all trucks hauling dirt, sand, soil, or other loose materials, or maintain at least 2 ft (0.6 meter) of freeboard (vertical space between the top of the load and the top of the trailer) in accordance with the requirements of California Vehicle Code Section 23114.  Reduce traffic speeds on all unpaved roads to 15 miles per hour (mph) or less.

These Rule 403 measures were incorporated in the CalEEMod analysis.

Architectural Coatings. Architectural coatings contain VOCs that are part of the O3 precursors.

Based on the proposed project, it is estimated that application of the architectural coatings for the proposed peak construction day would result in a peak of 4 pounds per day (lbs/day) of VOCs. Therefore, VOC emissions from architectural‐coating application would not exceed the SCAQMD VOC threshold of 75 lbs/day.

Localized Impacts Analysis
. Table 6 shows the portion of the construction emissions that would be produced on the project sites compared to the LSTs. Table 6 shows that the localized construction emissions would not result in a locally significant air quality impact.

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Emissions Sources  Pollutant Emissions (lbs/day)
NOX  CO  PM10  PM2.5
On‐Site Emissions  16  16  1  1
LST  124  647  4  3
Exceeds Threshold?  No  No  No  No
Source: Compiled by LSA Associates, Inc. (August 2023).

Note: The SRA is Santa Clarita Valley, 1.2 ac, receptors at 80 feet. ac = acre
CO = carbon monoxide
lbs/day = pounds per day
LST = localized significance threshold
NOX = nitrogen oxides
PM2.5 = particulate matter less than 2.5 microns in size PM10 = particulate matter less than 10 microns in size
SRA = Source Receptor Area

Odors from Construction Activities. Heavy‐duty equipment in the project area during construction would emit odors, primarily from the equipment exhaust. However, the construction‐produced odors would cease to occur after individual construction is completed.

No other sources of objectionable odors have been identified for the proposed project, and no mitigation measures are r equired.

SCAQMD Rule 402 regarding nuisances states,
“A person shall not discharge from any source whatsoever such quantities of air contaminants or other material which cause injury, detriment, nuisance, or annoyance to any considerable number of persons or to the public, or which endanger the comfort, repose, health or safety of any such person s or the public, or which cause, or have a natural tendency to cause, injury or damage to business or property.”
The proposed uses are not anticipated to emit any objectionable odors. Therefore, objectionable odors posing a health risk to potential on‐site and existing off‐site uses would not occur as a result of the prop
osed project.

Naturally Occurring Asbestos. The proposed project site is in Los Angeles County, which is among the counties found to have serpentine and ultramafic rock in their soils (California Department of Conservation 2023). However, according to the California Geological Survey, no such rock has been
identified in the project vicinity. Therefore, the potential risk for naturally occurring asbestos during project construction is small and less than significant.

Construction Emissions Conclusions. Tables 5 and 6 show that daily regional construction emissions would not exceed the daily thresholds of any criteria pollutant emission thresh olds established by SCAQMD; thus, during construction, there would be no air quality impacts.

Operational Emissions
Long‐term air pollutant emission impacts are those associated with mobile sources (e.g., vehicle trips), energy sources (e.g., electricity and natural gas) and area sources (e.g., architectural coatings and the use of landscape maintenance equipmen t) related to the proposed project.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 16 PM10 emissions result from running exhaust, tire and brake wear, and the entrainment of dust into the atmosphere from vehicles traveling on paved roadways. Entrainment of PM10 occurs when vehicle tires pulverize small rocks and pavement and the vehicle wakes generate airborne dust. The contribution of tire and brake wear is small compared to the other PM emission processes.

Gasoline‐powered engines have small rates of particulate matter emissions compared with diesel‐ powered vehicles. Project traffic is described in the Transportation  Memorandum (LSA 2022).

Energy source emissions result from activities in buildings for which electricity and natural gas are used. The quantity of emissions is the product of usage intensity (i.e., the amount of electricity or natural gas) and the emission factor of the fuel source. Major sources of energy demand i nclude building mechanical systems, such as heating and air conditioning, lighting, and plug‐in electronics, such as refrigerators or computers. Greater building or appliance efficiency reduces the amount of energy for a given activity and thus lowers the resultant emissions. The emission factor is determined by the fuel source, with cleaner energy  sources, like renewable energy, producing fewer emissions than conventional sources.

Typically, area source emissions consist of direct sources of air emissions located at the project site, including architectural coatings and the use of landscape maintenance equipment. Area source emissions associated with the project would include emissions from the use of la ndscaping equipment and the use of consumer products.

Emission estimates for operation of the project were calculated using CalEEMod and are shown in Table 7, below. The primary emissions associated with the project are regional in nature, meaning that air pollutants are rapidly dispersed on release. The peak daily emissions associated with project operations are id
entified in Table 7 for reactive organic gas (ROG), nitrogen oxides (NOx), CO, sulfur oxides (SOx), PM10, and PM2.5.

Table 7: Project Operation Emissions (Pounds per Day)
ROG  NOx  CO  SOx  PM10  PM2.5
Area Source Emissions  1  <1  2  <1  <1  <1
Energy Source Emissions  <1  <1  <1  <1  <1  <1
Mobile Source Emissions  2  1  15  <1  3  <1
Total Project Emissions  3  2  15  <1  3  <1
SCAQMD Significance Threshold  55  55  550  150  55  150 Exceed Threshold?  No  No  No  No  No  No
Source: Compiled by LSA Associates, Inc. (August 2023).

CO = carbon monoxide
NOX = nitrogen oxides
PM2.5 = particulate matter less than 2.5 microns in size PM10 = particulate matter less than 10 microns in size
ROG = reactive organic gas
SCAQMD = South Coast Air Quality Management District
SOX = sulfur oxides

The results shown in Table 7 indicate the project would not exceed the significance criteria for annual ROG, NOx, CO, SOx, PM10, and PM2.5 emissions; therefore, operation of the proposed project would not 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 AAQS. The CalEEMod emission calculations sheets are included in Attachment C.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 17 Objectionable Odors.  The SCAQMD addresses odor criteria within the CEQA Handbook. The district has not established a rule or standard regarding odor emissions, rather, the district has a nuisance rule: “Any project with the potential to frequently expose members of the public to objectionable odors should be deemed to have a significant impa ct.”
The proposed project would not include any activities or operations that would generate objectionable odors. Therefore, the proposed project would not result in other emissions (such as those leading to odors) adversely affecting a substantial number of people.

Greenhouse Gas Impacts
Generate Greenhouse Gas Emissions
This section discusses the project’s impacts related to the release of GHG emissions for the construction and operational phases of the project.

Construction Activities. Construction activities associated with maximum buildout would produce combustion emissions from various sources. During construction, GHGs would be emitted through the operation of construction equi pment and from worker and builder supply vendor vehicles, each of which typically use fossil‐based fuels to operate. The combustion of fossil‐based fuels creates GHGs such as CO2, CH4, and N2O. Furthermore, CH4 is emitted during the fueling of heavy equipment. Exhaust emissions from on‐site construction activities would vary daily as construction activity levels change.

The SCAQMD does not have an adopted threshold of significance for construction‐related GHG emissions. Based on SCAQMD guidance, construction emissions were amortized over 30 years (a typical project lifet ime) to be added to the total project operational emissions. Using CalEEMod, it is estimated that construction activities would generate approximately 278 metric tons of CO2e. Thus, the amortized annual construction emissions would be approximately 9 MT of CO2e per year.

Operational GHG Emissions.  Long‐term GHG emissions are typically generated from mobile sources (e.g.,  cars,  trucks  and  buses),  area  sources  (e.g.,  maintenance  activities  and  landscaping),  indirect emissions from sources associated with energy consumption, waste sources (land filling and waste disposal),  and  water  sources  (water  supply  and  conveyance,  treatment,  and  distribution).  Mobile‐ source  GH
G  emissions  would  include  project‐generated  vehicle  and  truck  trips  to  and  from  the project.  Area‐source  emissions  would  be  associated  with  activities  such  as  landscaping  and maintenance  on  the  project  site.  Energy  source  emissions  would  be  generated  at  off‐site  utility providers  as  a  result  of  increased  el ectricity  demand  generated  by  the  project.  Waste  source emissions  generated  by  the  proposed  project  include  energy  generated  by  land  filling  and  other methods of disposal related to transporting and managing project generated waste. In addition, water source  emissions  associated  with  the  proposed  project  are  generated  by  water  supply  and conveyance, water treatm
ent, water distribution, and wastewater treatment.

As described above, this analysis evaluates potential operational emissions associated with the proposed project. Operational GHG emissions were estimated using CalEEMod and the results are presented in Table 8.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 18 Table 8: Operational GHG Emissions
Emissions Source Category  Operational Emissions (Metric Tons per Year) CO2  CH4  N2O  CO2e
Area  1  <1  0  1
Energy  110  <1  <1  110
Mobile  520  <1  <1  529
Waste  4  <1  0  15
Water  4  <1  <1  6
Total Annual Operational Emissions  661
30‐Year Amortized Construction Emissions  9
Total Annual Effective Project Emissions  670
SCAQMD Tier 3 Threshold  3,000
Would the Project Exceed the Threshold?  No
Source: Compiled by LSA Associates, Inc. (August 2023).

CH4 = methane
CO2 = carbon dioxide
CO2e = carbon dioxide equivalent
N2O = nitrous oxide
SCAQMD = South Coast Air Quality Management District

As shown in Table 8, the project would generate 670 metric tons of CO2e per year. This is less than SCAQMD’s Tier 3 threshold of 3,000 MT CO2e/yr.

Consistency with Greenhouse Gas Reduction Plans
The following discussion evaluates the proposed project according to the goals of the 2022 Scoping Plan, EO B‐30‐15, SB 32, and AB 197.

EO B‐30‐15 added the immediate target of reducing GHG emissions to 40 percent below 1990 levels by 2030. CARB released a sec ond update to the Scoping Plan, the 2017 Scoping Plan, to reflect the 2030 target set by EO B‐30‐15 and codified by SB 32. SB 32 affirms the importance of addressing climate change by codifying into statute the GHG emissions reductions target of at least 40 percent below 1990 leve
ls by 2030 contained in EO B‐30‐15. SB 32 builds on AB 32 and keeps us on the path toward achieving the State’s 2050 objective of reducing emissions to 80 percent below 1990 levels.

The companion bill to SB 32, AB 197, provides additional direction to the CARB related to the adoption of st
rategies to reduce GHG emissions. Additional direction in AB 197 intended to provide easier public access to air emissions data that are collected by CARB was posted in December 2016.

In addition, the 2022 Scoping Plan assesses progress toward the statutory 2030 target, wh ile laying out a path to achieving carbon neutrality no later than 2045. The 2022 Scoping Plan focuses on outcomes needed to achieve carbon neutrality by assessing paths for clean technology, energy deployment, natural and working lands, and others, and is designed to meet the State’s long‐term climate objectives and support a range of economic, environmental, energy security, environmental justice, and public health
priorities.

The 2022 Scoping Plan focuses on building clean energy production and distribution infrastructure for a carbon‐neutral future, including transitioning existing energy production and transmission infrastructure to produce zero‐carbon electricity and hydrogen, and utilizing biogas resulting from wildfire
management or landfill and dairy operations, among other substitutes. The 2022 Scoping Plan states that in almost all sectors, electrification will play an important role. The 2022 Scoping

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 19 Plan evaluates clean energy and technology options and the transition away from fossil fuels, including adding four times the solar and wind capacity by 2045 and about 1,700 times the amount of current hydrogen supply. As discussed in the 2022 Scoping Plan, EO N‐79‐20 requires that all new passenger vehicles sold in California will be zero‐emission by 2035, and all other fleets will ha ve
transitioned to zero‐emission as fully possible by 2045, which will reduce the percentage of fossil fuel combustion vehicles.

Energy efficient measures are intended to maximize energy efficiency building and appliance standards, pursue additional efficiency efforts includi ng new technologies and new policy and implementation mechanisms, and pursue comparable investment in energy efficiency from all retail providers of electricity in California. In addition, these measures are designed to expand the use of green building practices to reduce the carbon footprint of California’s new and existing inventory of buildings. As discussed above, the proposed project would compl y with the CALGreen Code,
regarding energy conservation and green building standards. Therefore, the proposed project would comply with applicable energy measures.

Water conservation and efficiency measures are intended to continue efficiency programs and use cleaner energy sources to move and treat water. In creasing the efficiency of water transport and reducing water use would reduce GHG emissions. As noted above, the project would comply with the CALGreen Code, which includes a variety of different measures, including reduction of wastewater and water use. In addition, the proposed project would be required to comply wit h  the California Model Water Efficient Landscape Ordinance. Therefore, the proposed project would not conflict with any of the water conservation and efficiency measures.

The goal of transportation and motor vehicle measures is to develop regional GHG emissions reduction targets for passenger vehicles. Specific regional emission targets for transportation emissions would not  directly apply to the proposed project. The second phase of Pavley standards will reduce GHG emissions from new cars by 34 percent from 2016 levels by 2025, resulting in a 3 percent decrease in average vehicle emissions for all vehicles by 2020. Vehicles traveling to the project site would com ply  with the Pavley II (LEV III) Advanced Clean Cars Program (CARB n.d.‐b).

Therefore, the proposed project would not conflict with the identified transportation and motor vehicle measures.

The CARB’s 2022 Scoping Plan provides Table 3 “Key Residential and Mixed‐Use Project Attributes that Reduce GHGs” in Appendix D. The table is provided by CARB for use in determining whether a proposed residential or mixed
‐use residential development would align with the State’s climate goals, absent a locally or regionally adopted CEQA‐qualified CAP. Table 9 shows the project’s consistency with these attributes.

As described in CARB’s 2022 Scoping Plan, residential and mixed ‐use development projects that incorporate all of the applicable key project attributes are aligned with the State’s priority GHG reduction strategies for local climate action and with the State’s climate and housing goals. As shown in Table 9, the project would be considered to be consistent with the Scoping Plan.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 20 Table 9: Key Residential and Mixed‐Use Project Attributes that Reduce GHGs Priority Areas   Key Project Attribute  Project Consistency Transportation
Electrification
Provides EV charging infrastructure that, at
minimum, meets the most ambitious voluntary
standard in the California Green Building
Standards Code at the time of project approval.

Consistent: Project provides charging
infrastructure for 49 electrical vehicles.

VMT Reduction
Is located on infill sites that are surrounded by
existing urban uses and reuses or redevelops
previously undeveloped or underutilized land
that is presently served by existing utilities and
essential public services (e.g., transit, streets,
water, sewer).

Consistent: Project development is
surrounded by existing urban uses and
reuses and presently served by exi sting
utilities and essential public services. It is
adjacent to a major City arterial.

Does not result in the loss or conversion of
natural and working lands.

Consistent: Project site is an existing parking
lot, thus not affecting natural and working
land.

Consists of transit‐supportive densities (minimum
of 20 residential dwelling units per acre), or is in
proximity to existing transit stops (within a half
mile), or satisfies more detailed and stringent
criteria specified in the region’s SCS.

Consistent: The zoning allows the project to
comply, the project provides 30 units in 1.53
acres for mix‐used
development. The project
is within 250 feet of a bus stop.

Reduces parking requirements by: eliminating
parking requirements or including maximum
allowable parking ratios (i.e., the ratio of parking
spaces to residential units or square feet); or
providing residential parking supply at a ratio of
less than one parking space per dwelling unit; or
for multifamily residential development,
requiring parking costs to be unbundled from
cos
ts to rent or own a residential unit.

Consistent: Parking provided at a ratio of
one parking space per unit, with shared
credit between the commercial visitors and
residential unit visitors. A shared parking
analysis was provided by a traffic engineer.

At least 20 percent of units included are
affordable to lower‐income residents.

Not Applicable: The project does not include
an affordable housing component; however,
the project would include one‐bedroom
units that would be accessible to various
income levels and consistent with the
density goals of the Scoping Plan.

Results in no net loss of existing affordable units.

Consistent: The project would not result in
the loss of existing affordable units.

Building
Decarbonization
Uses all‐electric appliances without any natural
gas connections and does not use propane or
other fossil fuels for space heating, water
heating, or indoor cooking.

Consistent: All appliances to be electrical.

Source: CARB 2022 Scoping Plan (CARB 2022).

EV = electric vehicle
GHG = greenhouse gas
SCS = Sustainable Communities Strategy
VMT = vehicle miles traveled

Per CARB guidance, as included in Appendix D of the CARB 2022 Scoping Plan, since the proposed project includes the applicable Local Actions included in Table 9 it would therefore also be considered consistent with the goals of the State and the 2022 Scoping Plan. As such, the proposed project is considered to be consistent with other plans, policies, or regulations adop ted for the purposes of reducing GHGs. Furthermore, as the proposed project would meet all requirements of

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 21 Title 24, CalGreen, and the City’s municipal code, and would incorporate the emission reduction measures included in the City’s CAP, the proposed project would not conflict with the goals of the City’s General Plan or CAP.

In addition, the 2020–2045 RTP/SCS was determined by CARB to achieve CARB’s 2035 GHG reduction targets; therefore, consistency
with the RTP/SCS would demonstrate consistency with the 2022 Scoping Plan. As further discussed in the Transportation Memorandum prepared for the proposed project (LSA 2022), the proposed project meets the City’s vehicle miles traveled screening criteria and would have a less than significant impact on the transportation system based on the significan
ce thresholds in Appendix G of the State CEQA Guidelines. Furthermore, the proposed project includes infrastructure to support electrification, and introduces a mix of land uses in an urban area, with residential housing located near workspaces and retail shopping. Therefore, the proposed project would not conflict with the goals of the RTP/SCS.

The low level
of project GHG emissions shown in Table 8 combined with the attributes shown in Table 9 indicate that the project would be compliant with all City, regional, and State GHG emissions reduction plans. Therefore, the proposed project’s GHG emissions would not result in a significant impact.

STANDARD CONDITIONS
Construction
The project is required to comply with regional rules that assist in reducing short‐term air pollutant emissions. SCAQMD Rule 403 requires that fugitive dust be controlled with the best‐available control measures so that the presence of such dust does not remain visible in the atmosphere beyond the property line of the emission source (SCAQMD 2005). In addition, SCAQ MD Rule 403 requires implementation of dust suppression techniques to prevent fugitive dust from creating a nuisance off site. Applicable dust suppression techniques from Rule 403 are summarized below.

Implementation of these dust suppression techniques can reduce the fugitive dust generation (and thus the PM10 component). Compliance with these rules would reduce impacts on nearby sensitive receptors (SCAQMD 2005). As shown in Table 5, implementation of Rule 403 measures results in dust emissions below SCAQMD thresholds.

The applicable Rule 403 measures are as follows:
 Apply nontoxic chemical soil stabilizers according to manufacturers’ specifications to all inactive construction areas
(previously graded areas inactive for 10 days or more).  Water active sites at least twice daily (locations where grading is to occur shall be thoroughly watered prior to earthmoving).
 Cover all trucks hauling dirt, sand, soil, or other loose materials, or maintain at least 2 feet (0.6 meter) of freeboard (vertical space between the top of the loa d and the top of the trailer) in
accordance with the requirements of California Vehicle Code Section 23114.  Pave construction access roads at least 100 feet (30 meters) onto the site from the main road.

10/9/23 «P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx» 22  Reduce traffic speeds on all unpaved roads to 15 mph or less.

The applicable California Department of Resources Recycling and Recovery (CalRecycle) Sustainable (Green) Building Program Measures are:
 Recycle/reuse at least 50 percent of the construction material (including, but not limited to, soil, mulch, vegetation, concrete, lumber, metal, and cardboard) (CalRecycle 2019a).  Use “green building ma
terials” such as those materials that are rapidly renewable or resource‐ efficient, and recycled and manufactured in an environmentally friendly way, for at least 10 percent of the project, as specified on the CalRecycle website (CalRecycle 2019b).

Operations
The proposed project is required to comply with the CALGreen Code and Title 24 of the California Code of Regulations established by the California Energy Commission regarding energy conservation and green building standards.

CONCLUSION
Based on the analysis presented above, the construction and operational emissions associated with the proposed project would not exceed SCAQMD established significance thresholds. The proposed project is not expected to produce significant emissions that would affect nearby sensitive receptors. The proposed project would also not result in objectionable odors affecting a substantial numb
er of people. GHG emissions released during operation of the project are estimated to be lower than significance thresholds and would not be cumulatively considerable. Additionally, the project would not conflict with the goals and objectives of State or regional plan, policy or regulation of an agency adopted for the purpose of redu cing GHG emissions.

Attachments:  A:   References
B:  Figures
C:  CalEEMod Output

A‐1

P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx (10/09/23) ATTACHMENT A

REFERENCES
California Air Resources Board (CARB). 2013. Amendments to California Cap‐and‐Trade Program.

April 9. Website: www.arb.ca.gov/sites/default/files/cap‐and‐trade/linkage/resolution13‐

7.pdf (accessed August 2023).
_____. 2022. Climate Change Scoping Plan: A Framework for Change. December. Website:
www.arb.ca.gov/our‐work/programs/ab‐32‐climate‐change‐scoping‐plan (accessed August 2023).
_____. n.d.‐a. Cap‐and‐Trade Program. Website: www.arb.ca.gov/our‐ work/programs/cap‐and‐ trade‐program (accessed August 2023).
_____. n.d.‐b. Low‐Emission Vehicle Greenhouse Gas Program. Website: www.arb.ca.gov/our‐ work/programs/advanced‐clean‐cars‐program/lev‐program/low‐emission‐vehicle‐ greenhouse‐gas (accessed August 2023).

California Department of Conservation (DOC). 2023. Naturally‐Occurring Asbestos in California.

Website: https://www.conservation.ca.gov/cgs/minerals/mineral‐hazards/asbestos (accessed August 2023).

California Department of Resources Recycling and Rec overy (CalRecycle). 2019a. Construction and Demolition Debris Recycling. Website: https://calrecycle.ca.gov/ConDemo/ (accessed August 2023).
_____. 2019b. Implementing the Governor’s Sustainable Building Executive Order: Sustainable (Green) Building Programs at CalRecycle. Website:
https://calrecycle.ca.gov/GreenBuilding/Programs/ (accessed August 2023).

City of Santa Clarita. 2011. City of Santa Clarita General Plan, Conservation and Open Spac e Element.

Website: www.codepublishing.com/CA/SantaClarita/html/SantaClaritaGP/6%20‐%20 Conservation%20and%20Open%20Space%20Element.pdf (accessed August 2023). _____. 2012. Climate Action Plan. August. Website: greensantaclarita.com/files/2012/10/ APPROVED‐CAP‐AUGUST‐2012.pdf (accessed August 2023).

Intergovernmental Panel on Climate Change (IPCC). 2023. AR6 Synthesis Report: Climate Change 2023. Website: www.ipcc.ch/report/sixth‐assessment‐report‐cycle/ (accessed August 2023).

LSA. 2022. Transportation Memorandum for th e Promenade Flats Project, April.

A‐2

P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx (10/09/23) South Coast Air Quality Management District (SCAQMD). 1993. CEQA Air Quality Handbook. April.

Website: www.aqmd.gov/home/rules‐compliance/ceqa/air‐quality‐analysis‐handbook/ ceqa‐air‐quality‐handbook‐(1993) (accessed August 2023). _____. 2005. Rule 403. Fugitive Dust. Website: www.aqmd.gov/docs/default‐source/rule‐book/rule‐ iv/rule‐403.pdf (accessed August 2023).
_____. 2008. Final Localized Significance Threshold Methodology. June. Website: www.aqmd.gov/ docs/default‐source/ceqa/handbook/localized‐
significance‐thresholds/final‐lst‐
methodology‐document.pdf (accessed August 2023).
–––––.  2015. Multiple Air Toxics Exposure Study in the South Coast Air Basin (MATES‐IV). August.

Website: www.aqmd.gov/home/air‐quality/air‐quality‐studies/health‐studies/mates‐iv (accessed August 2023).
_____. 2016. Advisory Notice on Rule 1113. Website: www.aqmd.gov/docs/default‐source/rule‐ book/reg‐xi/r1113.pdf (accessed August 2023).
_____.
2019. South Coast AQMD Air Quality Significance Thresholds. April. Website:
https://www.aqmd.gov/docs/default‐source/ceqa/handbook/south‐coast‐aqmd‐air‐quality‐ significance‐thresholds.pdf?sfvrsn=25 (accessed August 2023). _____. 2022. Final 2022 Air Quality Management Plan. February. Website: www.aqmd.gov/home/ air‐quality/clean‐air‐plans/air‐quality‐mgt‐plan (accessed August 2023). _____. n.d. Air Quality Analysis Handbook. Website: www.aqmd.go v/home/rules‐compliance/ ceqa/air‐quality‐analysis‐handbook (accessed August 2023). _____. Greenhouse Gases (GHG) CEQA Significance Thresholds. Website: www.aqmd.gov/home/ regulations/ceqa/air‐quality‐analysis‐handbook/ghg‐significance‐thresholds/ (accessed August 2023).
_____. National Ambient Air Quality Standards (NAAQS) and California Ambient Air Quality Standards (CAAQS) Attainment Status for South Coast Air Basin. Website: www.aqmd.gov/ docs/default‐source/clean‐air‐plans/air‐quality‐management‐ plans/naaqs‐caaqs‐
feb2016.pdf (accessed August 2023).

United States Environmental Protection Agency (EPA). 2021a. Regulations for Emissions from Vehicles and Engines. Website: www.epa.gov/regulations‐emissions‐vehicles‐and‐engines/ final‐rule‐phase‐2‐greenhouse‐gas‐emissions‐standards (accessed August 2023). _____. 2021b. Final Rule to Revise Existing National GHG Emissions Standards for Passenger Cars and Light Tru
cks Through Model Year 2026. Website: www.epa.gov/regulations‐emissions‐ vehicles‐and‐engines/final‐rule‐revise‐existing‐national‐ghg‐emissions (accessed August 2023).

P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx «10/09/23» ATTACHMENT B

FIGURES

SOURCE: ArcGIS Online Topographic Map (2020)
Ven tu ra
County
Los
Angeles
County
27 170
126
14 118
405
210
5 I:\HAV2001\G\Project_LocaƟon.ai (10/6/2023)
FIGURE 1
Promenade Flats
Project LocaƟon
Project Vicinity
FEET
LEGEND
Project Site
0 500 1000
Project Location

NOT PART

OF THE PROJECT
SOURCE: CHARC Design
FEET
60300
FIGURE 2
I:\HAV2001\G\Site_Plan.ai (10/6/2023)
Promenade Flats
Site Plan
LEGEND
Project Site

P:\HAV2001\AQ‐GHG\Products\HAV2001 AQ‐GHG Memo_20231006.docx «10/09/23» ATTACHMENT C

CALEEMOD OUTPUT
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Santa Clarita Plaza (HAV2001) Custom Report
Table of Contents

1. Basic Project Information

1.1. Basic Project Information

1.2. Land Use Types

1.3. User-Selected Emission Reduction Measures by Emissions Sector

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds

2.2. Construction Emissions by Y ear, Unmitigated

2.4. Operations Emissions Compared Against Thresholds

2.5. Operations Emissions by Sector, Unmitigated

3. Construction Emissions Details

3.1. Demolition (2024) - Unmitigated

3.3. Site Preparation (2024) - Unmitigated

3.5. Grading (2024) - Unmitigated

3.7. Building Construction (2024) - Unmitigated
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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3.9. Paving (2024) - Unmitigated

3.11. Paving (2025) - Unmitigated

3.13. Architectural Coating (2024) - 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

4.3.2. Unmitigated

4.4. Water Emissions by Land Use

4.4.2. Unmitigated

4.5. Waste Emissions by Land Use

4.5.2. Unmitigated

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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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 Activities

5.6.2. Construction Earthmoving Control Strategies

5.7. Construction Paving

5.8. Construction Electricity Consumption and Emissions Factors

5.9. Operational Mobile Sources

5.9.1. Unmitigated

5.10. Operational Area Sources
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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

8. User Changes to Default Data
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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1. Basic Project Information

1.1. Basic Project Information
Data Field Value
Project Name Santa Clarita Plaza (HAV2001)
Construction Start Date 1/2/2024
Operational Y ear 2025
Lead Agency —
Land Use Scale Project/site
Analysis Level for Defaults County
Windspeed (m/s) 2.50
Precipitation (days) 16.0
Location 34.41859183266135, -118.54244801031707
County Los Angeles-South Coast
City Santa Clarita
Air District South Coast AQMD
Air Basin South Coast
TAZ 3623
EDFZ 7
Electric Utility Southern California Edison
Gas Utility Southern California Gas
App Version 2022.1.1.14

1.2. Land Use Types
Land Use Subtype Size Unit Lot Acreage Building Area (sq ft) Landscape Area (sq ft)
Special Landscape
Area (sq
ft)
Population Description
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
6 / 39
Condo/Townhouse 30.0 Dwelling Unit 1.00 31,800 11,042 0.00 89.0 — Health Club 3.03 1000sqft 0.00 3,027 0.00 0.00 — —
Regional Shopping
Center

7.27 1000sqft 0.00 7,266 0.00 0.00 — —
Parking Lot 0.53 Acre 0.53 0.00 4,892 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 (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 3.66 10.7 13.6 0.02 0.40 0.44 0.84 0.37 0.10 0.48 — 2,519 2,519 0.10 0.05 2.11 2,540 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 3.66 19.2 18.1 0.04 0.74 3.01 3.72 0.68 1.37 2.05 — 5,383 5,383 0.26 0.46 0.18 5,528 Average
Daily
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 1.59 7.10 8.72 0.01 0.28 0.34 0.62 0.25 0.09 0.34 — 1,658 1,658 0.07 0.04 0.58 1,672 Annual
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 0.29 1.30 1.59 < 0.005 0.05 0.06 0.11 0.05 0.02 0.06 — 274 274 0.01 0.01 0.10 277 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
7 / 39
—————————————————Exceeds
(Daily
Max)
Threshold 75.0 100 550 150 — — 150 — — 55.0 — — — — — — — Unmit. No No No No — — No — — No — — — — — — —
Exceeds
(Av
erage
Daily)
— — — — — — — — — — — — — — — — —
Threshold 75.0 100 550 150 — — 150 — — 55.0 — — — — — — — Unmit. No No No No — — No — — No — — — — — — —

2.2. Construction Emissions by Y ear, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Y ear ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily -
Summer
(Max)
— — — — — — — — — — — — — — — — —
2024 3.66 10.7 13.6 0.02 0.40 0.44 0.84 0.37 0.10 0.48 — 2,519 2,519 0.10 0.05 2.11 2,540 Daily -
Winter
(Max)
— — — — — — — — — — — — — — — — —
2024 3.66 19.2 18.1 0.04 0.74 3.01 3.72 0.68 1.37 2.05 — 5,383 5,383 0.26 0.46 0.18 5,528 2025 0.59 4.69 7.24 0.01 0.20 0.16 0.37 0.19 0.04 0.22 — 1,156 1,156 0.05 0.01 0.02 1,161 Average
Daily
— — — — — — — — — — — — — — — — —
2024 1.59 7.10 8.72 0.01 0.28 0.34 0.62 0.25 0.09 0.34 — 1,658 1,658 0.07 0.04 0.58 1,672 2025 < 0.005 0.02 0.03 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 4.53 4.53 < 0.005 < 0.005 < 0.005 4.55 Annual — — — — — — — — — — — — — — — — —
2024 0.29 1.30 1.59 < 0.005 0.05 0.06 0.11 0.05 0.02 0.06 — 274 274 0.01 0.01 0.10 277 2025 < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.75 0.75 < 0.005 < 0.005 < 0.005 0.75 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
8 / 39

2.4. Operations Emissions Compared Against Thresholds
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 3.28 1.58 17.0 0.03 0.04 2.84 2.88 0.04 0.72 0.76 28.9 3,932 3,960 3.13 0.15 12.1 4,096 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 3.03 1.69 14.0 0.03 0.04 2.84 2.87 0.04 0.72 0.76 28.9 3,791 3,820 3.14 0.16 0.58 3,946 Average
Daily
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 3.16 1.71 15.7 0.03 0.04 2.84 2.88 0.04 0.72 0.76 28.9 3,831 3,860 3.14 0.16 5.38 3,991 Annual
(Max)
— — — — — — — — — — — — — — — — —
Unmit. 0.58 0.31 2.87 0.01 0.01 0.52 0.52 0.01 0.13 0.14 4.79 634 639 0.52 0.03 0.89 661 Exceeds
(Daily
Max)
— — — — — — — — — — — — — — — — —
Threshold 55.0 55.0 550 150 — — 150 — — 55.0 — — — — — — — Unmit. No No No No — — No — — No — — — — — — —
Exceeds
(Av
erage
Daily)
— — — — — — — — — — — — — — — — —
Threshold 55.0 55.0 550 150 — — 150 — — 55.0 — — — — — — — Unmit. No No No No — — No — — No — — — — — — —

2.5. Operations Emissions by Sector, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
9 / 39
Sector ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Mobile 2.06 1.33 14.7 0.03 0.02 2.84 2.86 0.02 0.72 0.74 — 3,242 3,242 0.18 0.14 11.8 3,300 Area 1.21 0.02 2.15 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 0.00 6.39 6.39 < 0.005 < 0.005 — 6.41 Energy 0.01 0.23 0.12 < 0.005 0.02 — 0.02 0.02 — 0.02 — 663 663 0.05 < 0.005 — 665 Water — — — — — — — — — — 3.52 20.2 23.7 0.36 0.01 — 35.4 Waste — — — — — — — — — — 25.4 0.00 25.4 2.54 0.00 — 88.9 Refrig. — — — — — — — — — — — — — — — 0.28 0.28
Total 3.28 1.58 17.0 0.03 0.04 2.84 2.88 0.04 0.72 0.76 28.9 3,932 3,960 3.13 0.15 12.1 4,096 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Mobile 2.03 1.46 13.8 0.03 0.02 2.84 2.86 0.02 0.72 0.74 — 3,107 3,107 0.19 0.15 0.31 3,156 Area 0.99 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 Energy 0.01 0.23 0.12 < 0.005 0.02 — 0.02 0.02 — 0.02 — 663 663 0.05 < 0.005 — 665 Water — — — — — — — — — — 3.52 20.2 23.7 0.36 0.01 — 35.4 Waste — — — — — — — — — — 25.4 0.00 25.4 2.54 0.00 — 88.9 Refrig. — — — — — — — — — — — — — — — 0.28 0.28
Total 3.03 1.69 14.0 0.03 0.04 2.84 2.87 0.04 0.72 0.76 28.9 3,791 3,820 3.14 0.16 0.58 3,946 Average
Daily
— — — — — — — — — — — — — — — — —
Mobile 2.01 1.47 14.1 0.03 0.02 2.84 2.86 0.02 0.72 0.74 — 3,144 3,144 0.19 0.15 5.10 3,197 Area 1.14 0.01 1.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 0.00 4.38 4.38 < 0.005 < 0.005 — 4.39 Energy 0.01 0.23 0.12 < 0.005 0.02 — 0.02 0.02 — 0.02 — 663 663 0.05 < 0.005 — 665 Water — — — — — — — — — — 3.52 20.2 23.7 0.36 0.01 — 35.4 Waste — — — — — — — — — — 25.4 0.00 25.4 2.54 0.00 — 88.9 Refrig. — — — — — — — — — — — — — — — 0.28 0.28
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Total 3.16 1.71 15.7 0.03 0.04 2.84 2.88 0.04 0.72 0.76 28.9 3,831 3,860 3.14 0.16 5.38 3,991 Annual — — — — — — — — — — — — — — — — —
Mobile 0.37 0.27 2.58 0.01 < 0.005 0.52 0.52 < 0.005 0.13 0.14 — 520 520 0.03 0.02 0.85 529 Area 0.21 < 0.005 0.27 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 0.00 0.72 0.72 < 0.005 < 0.005 — 0.73 Energy < 0.005 0.04 0.02 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 110 110 0.01 < 0.005 — 110 Water — — — — — — — — — — 0.58 3.35 3.93 0.06 < 0.005 — 5.86 Waste — — — — — — — — — — 4.21 0.00 4.21 0.42 0.00 — 14.7 Refrig. — — — — — — — — — — — — — — — 0.05 0.05
Total 0.58 0.31 2.87 0.01 0.01 0.52 0.52 0.01 0.13 0.14 4.79 634 639 0.52 0.03 0.89 661

3. Construction Emissions Details

3.1. Demolition (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

1.61 15.6 16.0 0.02 0.67 — 0.67 0.62 — 0.62 — 2,494 2,494 0.10 0.02 — 2,502 Demolitio
n
— — — — — 2.13 2.13 — 0.32 0.32 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
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Off-Road
Equipment

0.02 0.21 0.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 34.2 34.2 < 0.005 < 0.005 — 34.3 Demolitio
n
— — — — — 0.03 0.03 — < 0.005 < 0.005 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment
< 0.005 0.04 0.04 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 5.66 5.66 < 0.005 < 0.005 — 5.67 Demolitio
n
— — — — — 0.01 0.01 — < 0.005 < 0.005 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.06 0.07 0.80 0.00 0.00 0.16 0.16 0.00 0.04 0.04 — 167 167 0.01 0.01 0.02 169 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.06 3.53 1.31 0.02 0.03 0.72 0.75 0.03 0.20 0.23 — 2,722 2,722 0.15 0.44 0.16 2,856 Average
Daily
— — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 0.01 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 2.33 2.33 < 0.005 < 0.005 < 0.005 2.36 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling < 0.005 0.05 0.02 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 37.3 37.3 < 0.005 0.01 0.04 39.2 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.39 0.39 < 0.005 < 0.005 < 0.005 0.39 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling < 0.005 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 6.17 6.17 < 0.005 < 0.005 0.01 6.48 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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3.3. Site Preparation (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

1.43 13.7 12.9 0.02 0.65 — 0.65 0.59 — 0.59 — 2,064 2,064 0.08 0.02 — 2,071 Dust
From
Mater
ial
Movement
— — — — — 2.44 2.44 — 1.17 1.17 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.01 0.07 0.07 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 11.3 11.3 < 0.005 < 0.005 — 11.3 Dust
From
Mater
ial
Movement
— — — — — 0.01 0.01 — 0.01 0.01 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment
< 0.005 0.01 0.01 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.87 1.87 < 0.005 < 0.005 — 1.88 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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———————< 0.005< 0.005—< 0.005< 0.005—————Dust
From
Mater
ial
Movement
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.03 0.04 0.48 0.00 0.00 0.10 0.10 0.00 0.02 0.02 — 100 100 < 0.005 < 0.005 0.01 102 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.56 0.56 < 0.005 < 0.005 < 0.005 0.57 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.09 0.09 < 0.005 < 0.005 < 0.005 0.09 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

3.5. Grading (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

1.65 15.9 15.4 0.02 0.74 — 0.74 0.68 — 0.68 — 2,454 2,454 0.10 0.02 — 2,462 Dust
From
Mater
ial
Movement
— — — — — 2.76 2.76 — 1.34 1.34 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.02 0.17 0.17 < 0.005 0.01 — 0.01 0.01 — 0.01 — 26.9 26.9 < 0.005 < 0.005 — 27.0 Dust
From
Mater
ial
Movement
— — — — — 0.03 0.03 — 0.01 0.01 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment
< 0.005 0.03 0.03 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 4.45 4.45 < 0.005 < 0.005 — 4.47 Dust
From
Mater
ial
Movement
— — — — — 0.01 0.01 — < 0.005 < 0.005 — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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—————————————————Daily,
Summer
(Max)
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.04 0.06 0.64 0.00 0.00 0.13 0.13 0.00 0.03 0.03 — 134 134 0.01 < 0.005 0.01 135 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 0.01 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 1.49 1.49 < 0.005 < 0.005 < 0.005 1.51 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.25 0.25 < 0.005 < 0.005 < 0.005 0.25 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

3.7. Building Construction (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

1.13 9.44 10.1 0.02 0.37 — 0.37 0.34 — 0.34 — 1,801 1,801 0.07 0.01 — 1,807 Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

1.13 9.44 10.1 0.02 0.37 — 0.37 0.34 — 0.34 — 1,801 1,801 0.07 0.01 — 1,807 Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.68 5.69 6.09 0.01 0.22 — 0.22 0.21 — 0.21 — 1,086 1,086 0.04 0.01 — 1,089 Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.12 1.04 1.11 < 0.005 0.04 — 0.04 0.04 — 0.04 — 180 180 0.01 < 0.005 — 180 Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.11 0.12 1.90 0.00 0.00 0.33 0.33 0.00 0.08 0.08 — 356 356 0.01 0.01 1.40 361 Vendor < 0.005 0.19 0.09 < 0.005 < 0.005 0.04 0.04 < 0.005 0.01 0.01 — 158 158 0.01 0.02 0.43 165 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.11 0.14 1.61 0.00 0.00 0.33 0.33 0.00 0.08 0.08 — 337 337 0.02 0.01 0.04 341 Vendor < 0.005 0.19 0.09 < 0.005 < 0.005 0.04 0.04 < 0.005 0.01 0.01 — 158 158 0.01 0.02 0.01 165 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Worker 0.07 0.09 1.02 0.00 0.00 0.20 0.20 0.00 0.05 0.05 — 206 206 0.01 0.01 0.36 209 Vendor < 0.005 0.12 0.06 < 0.005 < 0.005 0.03 0.03 < 0.005 0.01 0.01 — 95.2 95.2 < 0.005 0.01 0.11 99.3 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker 0.01 0.02 0.19 0.00 0.00 0.04 0.04 0.00 0.01 0.01 — 34.1 34.1 < 0.005 < 0.005 0.06 34.6 Vendor < 0.005 0.02 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 15.8 15.8 < 0.005 < 0.005 0.02 16.4 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

3.9. Paving (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.53 4.90 6.53 0.01 0.23 — 0.23 0.21 — 0.21 — 992 992 0.04 0.01 — 995 Paving 0.04 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.04 0.40 0.54 < 0.005 0.02 — 0.02 0.02 — 0.02 — 81.5 81.5 < 0.005 < 0.005 — 81.8 Paving < 0.005 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.01 0.07 0.10 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 13.5 13.5 < 0.005 < 0.005 — 13.5 Paving < 0.005 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.06 0.07 0.80 0.00 0.00 0.16 0.16 0.00 0.04 0.04 — 167 167 0.01 0.01 0.02 169 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Worker < 0.005 0.01 0.07 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 14.0 14.0 < 0.005 < 0.005 0.02 14.1 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 0.01 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 2.31 2.31 < 0.005 < 0.005 < 0.005 2.34 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

3.11. Paving (2025) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.49 4.63 6.50 0.01 0.20 — 0.20 0.19 — 0.19 — 992 992 0.04 0.01 — 995 Paving 0.04 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment
< 0.005 0.02 0.03 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 3.88 3.88 < 0.005 < 0.005 — 3.89 Paving < 0.005 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 0.64 0.64 < 0.005 < 0.005 — 0.64 Paving < 0.005 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.05 0.06 0.74 0.00 0.00 0.16 0.16 0.00 0.04 0.04 — 164 164 0.01 0.01 0.02 166 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.65 0.65 < 0.005 < 0.005 < 0.005 0.66 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.11 0.11 < 0.005 < 0.005 < 0.005 0.11 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

3.13. Architectural Coating (2024) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.14 0.91 1.15 < 0.005 0.03 — 0.03 0.03 — 0.03 — 134 134 0.01 < 0.005 — 134 Architectu
ral
Coatings

2.25 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.14 0.91 1.15 < 0.005 0.03 — 0.03 0.03 — 0.03 — 134 134 0.01 < 0.005 — 134 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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————————————————2.25Architectu
ral
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.04 0.28 0.35 < 0.005 0.01 — 0.01 0.01 — 0.01 — 40.6 40.6 < 0.005 < 0.005 — 40.7 Architectu
ral
Coatings

0.68 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Off-Road
Equipment

0.01 0.05 0.06 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 6.72 6.72 < 0.005 < 0.005 — 6.75 Architectu
ral
Coatings

0.13 — — — — — — — — — — — — — — — —
Onsite
truc
k

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Offsite — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.02 0.02 0.38 0.00 0.00 0.07 0.07 0.00 0.02 0.02 — 71.2 71.2 < 0.005 < 0.005 0.28 72.2 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Worker 0.02 0.03 0.32 0.00 0.00 0.07 0.07 0.00 0.02 0.02 — 67.4 67.4 < 0.005 < 0.005 0.01 68.3 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Average
Daily
— — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.10 0.00 0.00 0.02 0.02 0.00 < 0.005 < 0.005 — 20.8 20.8 < 0.005 < 0.005 0.04 21.1 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Annual — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 0.02 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 3.45 3.45 < 0.005 < 0.005 0.01 3.49 Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse

0.47 0.38 4.29 0.01 0.01 0.90 0.91 0.01 0.23 0.23 — 1,017 1,017 0.05 0.04 3.75 1,034 Health
Club

0.33 0.20 2.16 < 0.005 < 0.005 0.40 0.40 < 0.005 0.10 0.10 — 458 458 0.03 0.02 1.66 467 Regional
Shopping
Center

1.25 0.76 8.28 0.02 0.01 1.54 1.55 0.01 0.39 0.40 — 1,766 1,766 0.11 0.08 6.41 1,799 Parking
Lot

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Total 2.06 1.33 14.7 0.03 0.02 2.84 2.86 0.02 0.72 0.74 — 3,242 3,242 0.18 0.14 11.8 3,300 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse

0.47 0.41 3.93 0.01 0.01 0.90 0.91 0.01 0.23 0.23 — 974 974 0.05 0.04 0.10 988 Health
Club

0.32 0.22 2.05 < 0.005 < 0.005 0.40 0.40 < 0.005 0.10 0.10 — 440 440 0.03 0.02 0.04 447 Regional
Shopping
Center

1.23 0.83 7.86 0.02 0.01 1.54 1.55 0.01 0.39 0.40 — 1,694 1,694 0.11 0.08 0.17 1,721 Parking
Lot

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Total 2.03 1.46 13.8 0.03 0.02 2.84 2.86 0.02 0.72 0.74 — 3,107 3,107 0.19 0.15 0.31 3,156 Annual — — — — — — — — — — — — — — — — —
Condo/To
wnhouse

0.08 0.08 0.74 < 0.005 < 0.005 0.16 0.17 < 0.005 0.04 0.04 — 163 163 0.01 0.01 0.27 166 Health
Club

0.06 0.04 0.38 < 0.005 < 0.005 0.07 0.07 < 0.005 0.02 0.02 — 73.6 73.6 < 0.005 < 0.005 0.12 74.9 Regional
Shopping
Center

0.22 0.15 1.46 < 0.005 < 0.005 0.28 0.28 < 0.005 0.07 0.07 — 284 284 0.02 0.01 0.46 289 Parking
Lot

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 Total 0.37 0.27 2.58 0.01 < 0.005 0.52 0.52 < 0.005 0.13 0.14 — 520 520 0.03 0.02 0.85 529

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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—————————————————Daily,
Summer
(Max)
Condo/To
wnhouse
— — — — — — — — — — — 201 201 0.01 < 0.005 — 202
Health
Club
— — — — — — — — — — — 42.3 42.3 < 0.005 < 0.005 — 42.5
Regional
Shopping
Center
— — — — — — — — — — — 104 104 0.01 < 0.005 — 104
Parking
Lot
— — — — — — — — — — — 29.5 29.5 < 0.005 < 0.005 — 29.6
Total — — — — — — — — — — — 377 377 0.02 < 0.005 — 378
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — — 201 201 0.01 < 0.005 — 202
Health
Club
— — — — — — — — — — — 42.3 42.3 < 0.005 < 0.005 — 42.5
Regional
Shopping
Center
— — — — — — — — — — — 104 104 0.01 < 0.005 — 104
Parking
Lot
— — — — — — — — — — — 29.5 29.5 < 0.005 < 0.005 — 29.6
Total — — — — — — — — — — — 377 377 0.02 < 0.005 — 378
Annual — — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — — 33.2 33.2 < 0.005 < 0.005 — 33.4
Health
Club
— — — — — — — — — — — 7.01 7.01 < 0.005 < 0.005 — 7.03
Regional
Shopping
Center
— — — — — — — — — — — 17.2 17.2 < 0.005 < 0.005 — 17.3
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Parking
Lot
— — — — — — — — — — — 4.88 4.88 < 0.005 < 0.005 — 4.90
Total — — — — — — — — — — — 62.4 62.4 < 0.005 < 0.005 — 62.6

4.2.3. Natural Gas Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse

0.01 0.18 0.08 < 0.005 0.01 — 0.01 0.01 — 0.01 — 231 231 0.02 < 0.005 — 232 Health
Club
< 0.005 0.03 0.03 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 41.5 41.5 < 0.005 < 0.005 — 41.6 Regional
Shopping
Center
< 0.005 0.01 0.01 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 13.9 13.9 < 0.005 < 0.005 — 14.0 Parking
Lot

0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 0.00 0.00 0.00 0.00 — 0.00 Total 0.01 0.23 0.12 < 0.005 0.02 — 0.02 0.02 — 0.02 — 287 287 0.03 < 0.005 — 287 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse

0.01 0.18 0.08 < 0.005 0.01 — 0.01 0.01 — 0.01 — 231 231 0.02 < 0.005 — 232 Health
Club
< 0.005 0.03 0.03 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 41.5 41.5 < 0.005 < 0.005 — 41.6 Regional
Shopping
Center
< 0.005 0.01 0.01 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 13.9 13.9 < 0.005 < 0.005 — 14.0 Parking
Lot

0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 0.00 0.00 0.00 0.00 — 0.00 Total 0.01 0.23 0.12 < 0.005 0.02 — 0.02 0.02 — 0.02 — 287 287 0.03 < 0.005 — 287 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Annual — — — — — — — — — — — — — — — — —
Condo/To
wnhouse
< 0.005 0.03 0.01 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 38.3 38.3 < 0.005 < 0.005 — 38.4 Health
Club
< 0.005 0.01 0.01 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 6.88 6.88 < 0.005 < 0.005 — 6.89 Regional
Shopping
Center
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 2.31 2.31 < 0.005 < 0.005 — 2.31 Parking
Lot

0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 0.00 0.00 0.00 0.00 — 0.00 Total < 0.005 0.04 0.02 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 47.4 47.4 < 0.005 < 0.005 — 47.6

4.3. Area Emissions by Source

4.3.2. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Source ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Hearths 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 Consume
r
Products

0.90 — — — — — — — — — — — — — — — —
Architectu
ral
Coatings

0.08 — — — — — — — — — — — — — — — —
Landscap
e
Equipme
nt

0.23 0.02 2.15 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 6.39 6.39 < 0.005 < 0.005 — 6.41 Total 1.21 0.02 2.15 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 0.00 6.39 6.39 < 0.005 < 0.005 — 6.41 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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—————————————————Daily,
Winter
(Max)
Hearths 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 Consume
r
Products

0.90 — — — — — — — — — — — — — — — —
Architectu
ral
Coatings

0.08 — — — — — — — — — — — — — — — —
Total 0.99 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 Annual — — — — — — — — — — — — — — — — —
Hearths 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 Consume
r
Products

0.16 — — — — — — — — — — — — — — — —
Architectu
ral
Coatings

0.02 — — — — — — — — — — — — — — — —
Landscap
e
Equipme
nt

0.03 < 0.005 0.27 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 0.72 0.72 < 0.005 < 0.005 — 0.73 Total 0.21 < 0.005 0.27 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 0.00 0.72 0.72 < 0.005 < 0.005 — 0.73

4.4. Water Emissions by Land Use

4.4.2. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
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Condo/To — — — — — — — — — — 2.14 12.6 14.7 0.22 0.01 — 21.8 Health
Club
— — — — — — — — — — 0.34 1.78 2.12 0.04 < 0.005 — 3.26
Regional
Shopping
Center
— — — — — — — — — — 1.03 5.34 6.37 0.11 < 0.005 — 9.79
Parking
Lot
— — — — — — — — — — 0.00 0.53 0.53 < 0.005 < 0.005 — 0.53 Total — — — — — — — — — — 3.52 20.2 23.7 0.36 0.01 — 35.4 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — 2.14 12.6 14.7 0.22 0.01 — 21.8
Health
Club
— — — — — — — — — — 0.34 1.78 2.12 0.04 < 0.005 — 3.26
Regional
Shopping
Center
— — — — — — — — — — 1.03 5.34 6.37 0.11 < 0.005 — 9.79
Parking
Lot
— — — — — — — — — — 0.00 0.53 0.53 < 0.005 < 0.005 — 0.53 Total — — — — — — — — — — 3.52 20.2 23.7 0.36 0.01 — 35.4 Annual — — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — 0.35 2.08 2.43 0.04 < 0.005 — 3.61
Health
Club
— — — — — — — — — — 0.06 0.29 0.35 0.01 < 0.005 — 0.54
Regional
Shopping
Center
— — — — — — — — — — 0.17 0.88 1.06 0.02 < 0.005 — 1.62
Parking
Lot
— — — — — — — — — — 0.00 0.09 0.09 < 0.005 < 0.005 — 0.09 Total — — — — — — — — — — 0.58 3.35 3.93 0.06 < 0.005 — 5.86 Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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4.5. Waste Emissions by Land Use

4.5.2. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — 12.0 0.00 12.0 1.20 0.00 — 41.9
Health
Club
— — — — — — — — — — 9.31 0.00 9.31 0.93 0.00 — 32.6
Regional
Shopping
Center
— — — — — — — — — — 4.11 0.00 4.11 0.41 0.00 — 14.4
Parking
Lot
— — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — 25.4 0.00 25.4 2.54 0.00 — 88.9 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — 12.0 0.00 12.0 1.20 0.00 — 41.9
Health
Club
— — — — — — — — — — 9.31 0.00 9.31 0.93 0.00 — 32.6
Regional
Shopping
Center
— — — — — — — — — — 4.11 0.00 4.11 0.41 0.00 — 14.4
Parking
Lot
— — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — 25.4 0.00 25.4 2.54 0.00 — 88.9 Annual — — — — — — — — — — — — — — — — —
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Condo/To — — — — — — — — — — 1.98 0.00 1.98 0.20 0.00 — 6.94 Health
Club
— — — — — — — — — — 1.54 0.00 1.54 0.15 0.00 — 5.39
Regional
Shopping
Center
— — — — — — — — — — 0.68 0.00 0.68 0.07 0.00 — 2.38
Parking
Lot
— — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — 4.21 0.00 4.21 0.42 0.00 — 14.7

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land Use ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — — — — — — 0.23 0.23
Health
Club
— — — — — — — — — — — — — — — 0.01 0.01
Regional
Shopping
Center
— — — — — — — — — — — — — — — 0.03 0.03
Total — — — — — — — — — — — — — — — 0.28 0.28
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — — — — — — 0.23 0.23
Health
Club
— — — — — — — — — — — — — — — 0.01 0.01
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Regional
Shopping
Center
— — — — — — — — — — — — — — — 0.03 0.03
Total — — — — — — — — — — — — — — — 0.28 0.28
Annual — — — — — — — — — — — — — — — — —
Condo/To
wnhouse
— — — — — — — — — — — — — — — 0.04 0.04
Health
Club
— — — — — — — — — — — — — — — < 0.005 < 0.005
Regional
Shopping
Center
— — — — — — — — — — — — — — — 0.01 0.01
Total — — — — — — — — — — — — — — — 0.05 0.05

5. Activity Data

5.1. Construction Schedule
Phase Name Phase Type Start Date End Date Days Per Week Work Days per Phase Phase Description Demolition Demolition 1/2/2024 1/8/2024 5.00 5.00 —
Site Preparation Site Preparation 1/9/2024 1/10/2024 5.00 2.00 — Grading Grading 1/11/2024 1/16/2024 5.00 4.00 —
Building Construction Building Construction 1/17/2024 11/19/2024 5.00 220 — Paving Paving 11/20/2024 1/2/2025 5.00 32.0 —
Architectural Coating Architectural Coating 7/9/2024 12/10/2024 5.00 111 —

5.2. Off-Road Equipment

5.2.1. Unmitigated
Phase Name Equipment Type Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
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Demolition Concrete/Industrial
Saws
Diesel A verage 1.00 8.00 33.0 0.73
Demolition Rubber Tired Dozers Diesel Average 1.00 8.00 367 0.40 Demolition Tractors/Loaders/Backh
oes
Diesel Average 3.00 8.00 84.0 0.37
Site Preparation Graders Diesel Average 1.00 8.00 148 0.41 Site Preparation Rubber Tired Dozers Diesel Average 1.00 7.00 367 0.40 Site Preparation Tractors/Loaders/Backh
oes
Diesel Average 1.00 8.00 84.0 0.37
Grading Graders Diesel Average 1.00 8.00 148 0.41
Grading Rubber Tired Dozers Diesel Average 1.00 8.00 367 0.40 Grading Tractors/Loaders/Backh
oes
Diesel Average 2.00 7.00 84.0 0.37
Building Construction Cranes Diesel Average 1.00 6.00 367 0.29 Building Construction Forklifts Diesel Average 1.00 6.00 82.0 0.20 Building Construction Generator Sets Diesel Average 1.00 8.00 14.0 0.74 Building Construction Tractors/Loaders/Backh
oes
Diesel Average 1.00 6.00 84.0 0.37
Building Construction Welders Diesel Average 3.00 8.00 46.0 0.45 Paving Cement and Mortar
Mixers
Diesel A
verage 1.00 6.00 10.0 0.56
Paving Pavers Diesel Average 1.00 6.00 81.0 0.42
Paving Paving Equipment Diesel Average 1.00 8.00 89.0 0.36 Paving Rollers Diesel Average 1.00 7.00 36.0 0.38
Paving Tractors/Loaders/Backh
oes
Diesel Average 1.00 8.00 84.0 0.37
Architectural Coating Air Compressors Diesel Average 1.00 6.00 37.0 0.48

5.3. Construction Vehicles
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5.3.1. Unmitigated
Phase Name Trip Type One-Way Trips per Day Miles per Trip Vehicle Mix Demolition — — — —
Demolition Worker 12.5 18.5 LDA,LDT1,LDT2
Demolition Vendor — 10.2 HHDT,MHDT
Demolition Hauling 38.6 20.0 HHDT
Demolition Onsite truck — — HHDT
Site Preparation — — — —
Site Preparation Worker 7.50 18.5 LDA,LDT1,LDT2
Site Preparation Vendor — 10.2 HHDT,MHDT
Site Preparation Hauling 0.00 20.0 HHDT
Site Preparation Onsite truck — — HHDT
Grading — — — —
Grading Worker 10.0 18.5 LDA,LDT1,LDT2
Grading Vendor — 10.2 HHDT,MHDT
Grading Hauling 0.00 20.0 HHDT
Grading Onsite truck — — HHDT
Building Construction — — — —
Building Construction Worker 25.2 18.5 LDA,LDT1,LDT2
Building Construction Vendor 4.89 10.2 HHDT,MHDT
Building Construction Hauling 0.00 20.0 HHDT
Building Construction Onsite truck — — HHDT
Paving — — — —
Paving Worker 12.5 18.5 LDA,LDT1,LDT2
Paving Vendor — 10.2 HHDT,MHDT
Paving Hauling 0.00 20.0 HHDT
Paving Onsite truck — — HHDT
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Architectural Coating — — — —
Architectural Coating Worker 5.04 18.5 LDA,LDT1,LDT2
Architectural Coating Vendor — 10.2 HHDT,MHDT
Architectural Coating Hauling 0.00 20.0 HHDT
Architectural Coating Onsite truck — — HHDT

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies
Control Strategies Applied PM10 Reduction PM2.5 Reduction Water unpaved roads twice daily 55% 55%
Limit vehicle speeds on unpaved roads to 25 mph 44% 44% Sweep paved roads once per month 9% 9%

5.5. Architectural Coatings
Phase Name Residential Interior Area Coated
(sq ft)
Residential Exterior Area Coated
(sq ft)
Non-Residential Interior Area
Coated (sq
ft)
Non-Residential Exterior Area
Coated (sq
ft)
Parking Area Coated (sq ft)
Architectural Coating 64,395 21,465 15,450 5,150 1,385

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities
Phase Name Material Imported (Cubic Y ards) Material Exported (Cubic Y ards) Acres Graded (acres) Material Demolished (Ton of Debris)
Acres Paved (acres)
Demolition 0.00 0.00 0.00 772 —
Site Preparation 0.00 0.00 1.88 0.00 —
Grading 0.00 0.00 4.00 0.00 —
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Paving 0.00 0.00 0.00 0.00 0.53

5.6.2. Construction Earthmoving Control Strategies
Control Strategies Applied Frequency (per day) PM10 Reduction PM2.5 Reduction Water Exposed Area 2 61% 61%
Water Demolished Area 2 36% 36%

5.7. Construction Paving
Land Use Area Paved (acres) % Asphalt
Condo/Townhouse — 0%
Health Club 0.00 0%
Regional Shopping Center 0.00 0%
Parking Lot 0.53 100%

5.8. Construction Electricity Consumption and Emissions Factors kWh per Y ear and Emission Factor (lb/MWh)
Y ear kWh per Y ear CO2 CH4 N2O
2024 0.00 532 0.03 < 0.005
2025 0.00 532 0.03 < 0.005

5.9. Operational Mobile Sources

5.9.1. Unmitigated
Land Use Type Trips/Weekday Trips/Saturday Trips/Sunday Trips/Y ear VMT/Weekday VMT/Saturday VMT/Sunday VMT/Y ear Condo/Townhouse 136 136 136 49,713 1,269 1,269 1,269 463,175 Health Club 105 105 105 38,155 562 562 562 205,185
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
36 / 39
Regional Shopping
Center
396 396 396 144,486 2,168 2,168 2,168 791,222
Parking Lot 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated
Hearth Type Unmitigated (number)
Condo/Townhouse —
Wood Fireplaces 0
Gas Fireplaces 0
Propane Fireplaces 0
Electric Fireplaces 0
No Fireplaces 30
Conventional Wood Stoves 0
Catalytic Wood Stoves 0
Non-Catalytic Wood Stoves 0
Pellet Wood Stoves 0

5.10.2. Architectural Coatings
Residential Interior Area Coated (sq ft) Residential Exterior Area Coated (sq ft) Non-Residential Interior Area Coated (sq ft)
Non-Residential Exterior Area Coated
(sq ft)
Parking Area Coated (sq ft)
64395 21,465 15,440 5,147 1,385

5.10.3. Landscape Equipment
Season Unit Value
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
37 / 39
Snow Days day/yr 0.00
Summer Days day/yr 250

5.11. Operational Energy Consumption

5.11.1. Unmitigated
Electricity (kWh/yr) and CO2 and CH4 and N2O and Natural Gas (kBTU/yr) Land Use Electricity (kWh/yr) CO2 CH4 N2O Natural Gas (kBTU/yr) Condo/Townhouse 137,765 532 0.0330 0.0040 720,911
Health Club 29,041 532 0.0330 0.0040 129,579
Regional Shopping Center 71,363 532 0.0330 0.0040 43,502 Parking Lot 20,224 532 0.0330 0.0040 0.00

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated
Land Use Indoor Water (gal/year) Outdoor Water (gal/year) Condo/Townhouse 1,118,214 189,273
Health Club 179,204 0.00
Regional Shopping Center 538,507 0.00
Parking Lot 0.00 68,608

5.13. Operational Waste Generation

5.13.1. Unmitigated
Land Use Waste (ton/year) Cogeneration (kWh/year)
Condo/Townhouse 22.2 —
Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
38 / 39
Health Club 17.3 —
Regional Shopping Center 7.63 —
Parking Lot 0.00 —

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated
Land Use Type Equipment Type Refrigerant GWP Quantity (kg) Operations Leak Rate Service Leak Rate Times Serviced Condo/Townhouse Average room A/C &
Other residential
A/C
and heat pumps
R-410A 2,088 < 0.005 2.50 2.50 10.0
Condo/Townhouse Household refrigerators
and/or freez
ers
R-134a 1,430 0.12 0.60 0.00 1.00
Health Club Other commercial A/C
and heat
pumps
R-410A 2,088 < 0.005 4.00 4.00 18.0
Health Club Stand-alone retail
refriger
ators and
freezers
R-134a 1,430 0.04 1.00 0.00 1.00
Regional Shopping
Center
Other commercial A/C
and heat
pumps
R-410A 2,088 < 0.005 4.00 4.00 18.0
Regional Shopping
Center
Stand-alone retail
refriger
ators and
freezers
R-134a 1,430 0.04 1.00 0.00 1.00

8. User Changes to Default Data
Screen Justification
Land Use Main site area is 1.2 acres, new parking lot is 0.33 acres. The "Health Club" and Regional Shopping Center" are
within the Residential building.

Construction: Construction Phases Construction schedule planned to start in January 2024 and last approximately 12 months. Assume architectural
coatings applied during the Building Construction phase.

Construction: Architectural Coatings Assume all coatings comply with SCAQMD Rule 1113.

Santa Clarita Plaza (HAV2001) Custom Report, 8/9/2023
39 / 39
Operations: Vehicle Data Changes per traffic study and to match previous analysis.

Operations: Hearths No woodstoves or fireplaces
November 16, 2023
Santa Clarita Plaza Apartments Project for a Categorical Exemption as a Class 32 In-Fill Development (Envicom Project No. 2021-053-01)

Attachment D
Hydrology Report

TABLE OF CONTENTS

 Section 1.0: PROJECT SUMMARY
 1.1 Design Parameters
 1.2 Overview of Analysis Procedure
 1.3 Project Purpose and Scope
 1.4 Existing and Proposed Drainage conditions
 1.5 Hydrologic Analysis
 1.6 Low Impact Development Analysis
 1.7 Hydraulic Analysis
 1.8 Conclusion
 Section 2.0: HYDROLOGY CALCULATIONS
 Section 3.0: LOW IMPACT DEVELOPMENT CALCULATIONS
 Section 4.0: HYDRAULIC CALCULATIONS
 Appendix A: HYDROLOGY/LOW IMPACT DEVELOPMENT MAP

Section 1.0

PROJECT SUMMARY

1.1 DESIGN PARAMETERS
References: Los Angeles Department of Public Works, Hydrology Manual Los Angeles County Department of Public Works, LID Manual

Rainfall Isohyet:
85th Percentile, 24
-Hr Rainfall:

Soil Type:

Manning's Roughness Coefficient:

6.6 in (50yr – 24hr)

0.95 in
020
n=0.009, PVC

Note: Project not within County Adopted Flood Plain or Floodway. Project not within FEMA Flood Zone.

A Hydrology map delineating the Tributary Drainage areas and tabulated findings within this project for this tract is included
in the Appendix of this report.

1.2 OVERVIEW OF ANALYSIS PROCEDURES
Analysis of the stormdrain runoff for both the existing and proposed conditions used the same techniques for analysis. Those being as follows:
 Used LA County HydroCalc Program to determine times of concentration and peak flow rates.

Used LA County HydroCalc program to determine the SWQDv from the 85th percentile, 50-yr storm.

1.3 PROJECT PURPOSE AND SCOPE
The project site is the existing Santa Clarita Plaza Commercial Center located at 26111 to 26135 Bouquet Canyon Road, APNs 2811-003-016; -017, and -018. The site analyzed is

4.87 acres with existing infrastructure including buildings, parking lots, and underground utilities. The project proposes the development of an apartment building on the site along with surrounding parking stalls and planters. Additionally, the project site proposes the development of an overflow parking area to provided addition al parking spaces for residents and customers of the neighboring businesses.

1.4 EXISTING & PROPOSED DRAINAGE CONDITIONS
The site’s existing conditions and terrain force the runoff to sheet flow west bound across the parking lots, ultimately reaching existing catch basins that direct the runoff off site via an underground storm drainage system
.

The site’s proposed conditions and modifications change the drainage patterns of the site; the site continues to drain westbound and the runoff is collected by a network of concrete swales that convey it to catch basins connected to the existing storm drainage system. As part of the scope of work, a currently undeveloped lot will be resurfaced to allow for vehicle access and parking. The runoff will drain through this parking lot and reach a proposed underground infiltration trench beneath this lot.

1.5 HYDROLOGIC ANALYSIS
The methodology used to compute stormwater runoff was that described in the latest County of Los Angeles Hydrology Manual. The LA County HydroCalc program was also used for stormwater runoff calculation purposes. A 50-yr Storm is used for this analysis.

The site’s existing conditions were broken up and analyzed as three separate subareas (1A, 2A, and 3A ). These subareas drain westbound, ultimately leaving the site through three outlet points at existing catch basins.

Subarea 1A is the north portion of the site, while subarea 2A is the central portion of the site, and subarea 3A is the southernmost portion of the site. The terrain of the site allows for runoff to sheet flow across the lot and eventually leave the property.

The table
below summarizes the Existing Conditions Hydrologic Analysis.

Subarea Area (ac) Flowline (ft) TC (min) Q50 (cfs)
1A 0.65 343 5 2.23
1B 2.18 374 5 7.61
1C 2.04 740 9 5.29
Site Total 4.87 - - 15.13

There is a total area analyzed is 4.87 acres and generates a Q50 runoff of 15.13 cfs.

In the proposed conditions, the site breaks up into 3 separate subareas (1A, 2A, and 3A).

Subarea 1A consists of the northern half of the project site. This subarea includes a redesigned parking lot, trash enclosure, and a proposed apartment building. The runoff from this subarea drains west through a concrete swale and is intercepted by catch basins and routed off site. Subarea 2A consists of the lower half of the project site. This subarea includes the development of the overflow parking area occurring on APN: 2811-003-016.

R
unoff from this subarea sheet flows westward and is collected at a catch basin and a proposed storm drainage pipe conveys the runoff to a proposed area of infiltration.

The table below summarizes the Proposed Conditions Hydrologic Analysis:

Subarea Area (ac) Flowline (ft) TC (min) Q50 (cfs)
1A 2.83 417 6 8.99
1B 2.04 740 8 5.82
Site Total 4.87 - - 14.81

Comparing the existing and the proposed conditions, the runoff caused by the 50 year- storm decreased by -0.32 cfs for the proposed site.

The decrease in flow rate is due to the change in flow line lengths between the subareas analyzed in the two separate conditions. In the existing conditions, the site has three outlet locations and therefore is divided into three subareas. The proposed improvements modify the drainage pattern to only have two outlet points. Because of this, the runoff was rerouted and consequently extended the flow line length. This caused the time of concentration (Tc) to increase and therefore minimizes the amount of runoff at the point of confluence at any point in time, resulting in a decreased runoff rate.

1.6 LOW IMPACT DEVELOPMENT ANALYSIS
The methodology used for the Low Impact Development Analysis was that described in the County of Los Angeles Department of Public Works: Low Impact Development Standards manual February 2014. The HydroCalc Program was also used for Stormwater Quality Design Volume (SWQDv) calculation purposes. The 85th Percentile storm for the site is 0.95
inches, which is greater than the 0.75 inch storm; the 85th Percentile Storm was used to generate the SWQDv.

The site is analyzed as 1 subarea (1A), where the runoff drains westward.

The method in which the SWQDv will be handled will be through an underground infiltration device beneath the proposed overflow parking lot.

The table below summarizes the Low Impact Development Analysis.

Subarea Area
(ac)
Flowline
(ft)

IMP QPM
(cfs)
SWQDv
(ft3)
1A 2.04 740 0.82 0.36 5275
Site Total 2.04 - - 0.36 5275

The total area analyzed is 2.04
acres not including offsite areas and generates a Q PM of

0.36 cfs and a SWQDv of 5275 ft3.

1.7 HYDRAULIC ANALYSIS
The methodology used to analyze the Hydraulic capacity of the drainage devices on the site is Manning's equation. The roughness coefficient used is n=0.009 for PVC pipe and the design flow for these pipes are 70% full. The design storm used is the 50-yr storm runoff.

The proposed drainage system onsite is comprised of a 10” PVC pipe. The slope of the pipe is 9.3% and the actual flow in the system is calculated to be 5.82 cfs. The storm drain system has been designed to flow 70% full however the proposed pipe drains at a much lower volume than the 70% design value. See Section 4.0 for information on the pipe
system including flow depth, flow velocity, and pipe max capacity.

1.9 CONCLUSION
The site is comprised of 3 lots with existing infrastructure located at 26111 to 26135 Bouquet Canyon Road in the City of Santa Clarita, Ca. The runoff of the site generally sheet flows to the west where it enters an underground drainage system and drains offsite.

The proposed conditions include the incorporation of a residential building and improvements to the parking lot area to provide additional parking stalls and planters.

The runoff from areas that are affected by the improvements will continue to drain west and will be collected by respective catch basins and conveyed to an underground infiltration trench within the property. The overall drainage design of the site has been adequately designed to handle the runoff of a 5
0-yr storm and is consistent with the
requirements of the County of Los Angeles, Department of Public Works.

Section 2.0

HYDROLOGIC CALCULATIONS
(EXISTING CONDITIONS - HYDROCALC CALCULATOR)

Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/Existing/Output/3525 SC PLAZA EX Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 SC PLAZA EX
Subarea ID 1A
Area (ac) 0.65
Flow Path Length (ft) 343.0
Flow Path Slope (vft/hft) 0.01
50-yr Rainfall Depth (in) 6.6
Percent Impervious 0.8
Soil Type 20
Design Storm Frequency 50-yr
Fire Factor 0.34
LID False
Output Results
Modeled (50-yr) Rainfall Depth (in) 6.6
Peak Intensity (in/hr) 3.9377
Undeveloped Runoff Coefficient (Cu) 0.6585
Developed Runoff Coefficient (Cd) 0.8517
Time of Concentration (min) 5.0
Clear Peak Flow Rate (cfs) 2.18
Burned Peak Flow Rate (cfs) 2.233
24-Hr Clear Runoff Volume (ac-ft) 0.2677
24-Hr Clear Runoff Volume (cu-ft) 11662.659
Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/Existing/Output/3525 SC PLAZA EX Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 SC PLAZA EX
Subarea ID 2A
Area (ac) 2.18
Flow Path Length (ft) 374.0
Flow Path Slope (vft/hft) 0.01
50-yr Rainfall Depth (in) 6.6
Percent Impervious 0.87
Soil Type 20
Design Storm Frequency 50-yr
Fire Factor 0.34
LID False
Output Results
Modeled (50-yr) Rainfall Depth (in) 6.6
Peak Intensity (in/hr) 3.9377
Undeveloped Runoff Coefficient (Cu) 0.6585
Developed Runoff Coefficient (Cd) 0.8686
Time of Concentration (min) 5.0
Clear Peak Flow Rate (cfs) 7.4564
Burned Peak Flow Rate (cfs) 7.6141
24-Hr Clear Runoff Volume (ac-ft) 0.9582
24-Hr Clear Runoff Volume (cu-ft) 41740.5938
Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/Existing/Output/3525 SC PLAZA EX Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 SC PLAZA EX
Subarea ID 3A
Area (ac) 2.04
Flow Path Length (ft) 740.0
Flow Path Slope (vft/hft) 0.01
50-yr Rainfall Depth (in) 6.6
Percent Impervious 0.82
Soil Type 20
Design Storm Frequency 50-yr
Fire Factor 0.34
LID False
Output Results
Modeled (50-yr) Rainfall Depth (in) 6.6
Peak Intensity (in/hr) 2.9872
Undeveloped Runoff Coefficient (Cu) 0.6054
Developed Runoff Coefficient (Cd) 0.847
Time of Concentration (min) 9.0
Clear Peak Flow Rate (cfs) 5.1614
Burned Peak Flow Rate (cfs) 5.2865
24-Hr Clear Runoff Volume (ac-ft) 0.8562
24-Hr Clear Runoff Volume (cu-ft) 37296.2203

Section 2.0

HYDROLOGIC CALCULATIONS
(PROPOSED CONDITIONS - HYDROCALC CALCULATOR)

Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/Proposed/Output/3525 PROP Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 PROP
Subarea ID 1A
Area (ac) 2.83
Flow Path Length (ft) 417.0
Flow Path Slope (vft/hft) 0.01
50-yr Rainfall Depth (in) 6.6
Percent Impervious 0.84557318
Soil Type 20
Design Storm Frequency 50-yr
Fire Factor 0.34
LID False
Output Results
Modeled (50-yr) Rainfall Depth (in) 6.6
Peak Intensity (in/hr) 3.6144
Undeveloped Runoff Coefficient (Cu) 0.6406
Developed Runoff Coefficient (Cd) 0.8599
Time of Concentration (min) 6.0
Clear Peak Flow Rate (cfs) 8.796
Burned Peak Flow Rate (cfs) 8.9939
24-Hr Clear Runoff Volume (ac-ft) 1.2166
24-Hr Clear Runoff Volume (cu-ft) 52993.7042
Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/Proposed/Output/3525 PROP Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 PROP
Subarea ID 2A
Area (ac) 2.04
Flow Path Length (ft) 740.0
Flow Path Slope (vft/hft) 0.01
50-yr Rainfall Depth (in) 6.6
Percent Impervious 0.957041515
Soil Type 20
Design Storm Frequency 50-yr
Fire Factor 0.34
LID False
Output Results
Modeled (50-yr) Rainfall Depth (in) 6.6
Peak Intensity (in/hr) 3.1573
Undeveloped Runoff Coefficient (Cu) 0.6153
Developed Runoff Coefficient (Cd) 0.8878
Time of Concentration (min) 8.0
Clear Peak Flow Rate (cfs) 5.718
Burned Peak Flow Rate (cfs) 5.8158
24-Hr Clear Runoff Volume (ac-ft) 0.9668
24-Hr Clear Runoff Volume (cu-ft) 42113.9065

Section 3.0

LOW IMPACT DEVELOPMENT CALCULATIONS
(85th PERCENTILE STORM - HYDROCALC CALCULATOR)

Peak Flow Hydrologic Analysis
File location: F:/Job Files/3525- IHOP/Civil/Hydrology/Calculations/LID/Output/3525 SC PLAZA LID Report.pdf Version: HydroCalc 1.0.3
Input Parameters
Project Name 3525 SC PLAZA LID
Subarea ID 1A
Area (ac) 2.04
Flow Path Length (ft) 740.0
Flow Path Slope (vft/hft) 0.01
85th Percentile Rainfall Depth (in) 0.95
Percent Impervious 0.82
Soil Type 20
Design Storm Frequency 85th percentile storm
Fire Factor 0.34
LID True
Output Results
Modeled (85th percentile storm) Rainfall Depth (in) 0.95 Peak Intensity (in/hr) 0.2271
Undeveloped Runoff Coefficient (Cu) 0.1
Developed Runoff Coefficient (Cd) 0.756
Time of Concentration (min) 35.0
Clear Peak Flow Rate (cfs) 0.3503
Burned Peak Flow Rate (cfs) 0.3584
24-Hr Clear Runoff Volume (ac-ft) 0.1211
24-Hr Clear Runoff Volume (cu-ft) 5274.5435
STORM
WATER

NO HEAVY
Equipment Required

DETENTION / INFILTRATION
A new approach to underground stormwater storage, infiltration, treatment, harvesting or other stormwater management needs, subject to availability.

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Reshaping the Future of
Stormwater Management
Modular Polypropylene Cubes for Underground Water Storage CUDO components snap together, forming a single or
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the desired system size and shape, with a maximum
amount of footprint flexibility.

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requires just two modules and two end caps.

Per application, either a filter fabric or plastic liner is wrapped around the CUDO modules, encasing the entire
system. Geo-grid or other structural enhancement may be incorporated into the CUDO installation, depending on the loading requirements.

FEATURES AND BENEFITS
• Large interior openings offer ease of access for
inspection and maintenance
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and installation
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for assembly
• May be integrated into bioretention systems
(rain gardens)

NO HEAVY
Equipment Required
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oldcastleinfrastructure.com

Section 4.0

HYDRAULIC CALCULATIONS

Date: 04/14/23
Job: 3525 Santa Clarita Plaza
Hydraulic Calculations
Formula: Q= 50-yr Flow (cfs)
k'= 0.498 (at full capacity, See Hydraulic Table)
n= 0.009/0.013 (PVC/RCP, Mannings Roughness Coeff.)
b= Pipe Diameter (ft)
s= Slope of Pipe (ft/ft)
D= Flow Depth (ft)
A= Flow Area (ft2)
f'= Hydraulic Constant, see Hydraulic Table
v= flow velocity (ft/s)
d'= Depth Ratio, See Hydraulic Table
Line Q50 (cfs) b (in) s (ft/ft) k' d' D (ft) f' A (ft2) v (ft/s) QMAX (cfs) 1A 5.82 10 0.093 0.279 0.56 0.47 0.4626 0.321 18.1 10.38 1 of 1

Appendix A

HYDROLOGY/LOW IMPACT DEVELOPMENT MAP