SPERSS_Addendum.pdf — Salinas City Council, May 6, 2025

October 2024

C E Q A A D D E N D U M

SALINAS PROJECT TO ENHANCE REGIONAL STORMWATER SUPPLY (SPERSS)

PROJECT AND SALINAS STORM WATER MANAGEMENT PROJECT (SSWMP)

SALINAS , MONTEREY COUNTY, CALIFORNIA

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C E Q A A D D E N D U M

SALINAS PROJECT TO ENHANCE REGIONAL STORMWATER SUPPLY (SPERSS)

PROJECT AND SALINAS STORM WATER MANAGEMENT PROJECT (SSWMP)

SALINAS , MONTEREY COUNTY, CALIFORNIA

Submitted to:

Carollo Engineers, Inc.
2795 Mitchell Drive
Walnut Creek, CA 94598
(925) 932-1710

Prepared by:

LSA
285 South Street, Suite P
San Luis Obispo, CA 93401
(805) 782-0745

Project No. 20242021.01

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TABLE OF CONTENTS
LIST OF ABBREVIATIONS AND ACRONYMS ............................................................................................ iii

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

2.0 PRIOR ENVIRONMENTAL REVIEW ..................................................................... 2-1

2.1 2015 EIR ......................................................................................................................... 2-1

2.2 Addenda to the 2015 EIR............................................................................................... 2-2

2.2.1 Addendum #1................................................................................................................. 2-2

2.2.2 Addendum #2................................................................................................................. 2-2

2.2.3 Addendum #3................................................................................................................. 2-2

2.3 Supplemental 2021 EIR ................................................................................................. 2-2

2.4 Addendum to the 2021 SEIR ......................................................................................... 2-3

3.0 PROJECT DESCRIPTION ..................................................................................... 3-1

3.1 Project Location............................................................................................................. 3-1

3.2 Project Components ...................................................................................................... 3-1

3.3 Construction .................................................................................................................. 3-4

3.4 Operations and Maintenance ....................................................................................... 3-4

4.0 CEQA FRAMEWORK FOR USE OF AN ADDENDUM ............................................. 4-1

5.0 EVALUATION OF ENVIRONMENTAL EFFECTS ..................................................... 5-1

5.1 Aesthetics ...................................................................................................................... 5-1

5.2 Agriculture and Forestry Resources .............................................................................. 5-3

5.3 Air Quality ...................................................................................................................... 5-3

5.4 Biological Resources ...................................................................................................... 5-5

5.5 Cultural Resources....................................................................................................... 5-10

5.6 Energy .......................................................................................................................... 5-11

5.7 Geology and Soils ........................................................................................................ 5-13

5.8 Greenhouse Gas Emissions ......................................................................................... 5-16

5.9 Hazards and Hazardous Materials ............................................................................... 5-16

5.10 Hydrology and Water Quality ...................................................................................... 5-18

5.11 Land Use ...................................................................................................................... 5-24

5.12 Mineral Resources ....................................................................................................... 5-26

5.13 Noise ............................................................................................................................ 5-27

5.14 Population and Housing .............................................................................................. 5-28

5.15 Public Services ............................................................................................................. 5-29

5.16 Recreation ................................................................................................................... 5-31

5.17 Transportation ............................................................................................................. 5-31

5.18 Tribal Cultural Resources ............................................................................................ 5-33

5.19 Utilities and Service Systems ....................................................................................... 5-34

5.20 Wildfire ........................................................................................................................ 5-34

6.0 DETERMINATION .............................................................................................. 6-1

6.1 Substantial Changes to the Project ............................................................................... 6-1

6.2 Substantial Changes in Circumstances .......................................................................... 6-1

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6.3 New Information ........................................................................................................... 6-1

7.0 CONCLUSION .................................................................................................... 7-1

APPENDIX
A: MITIGATION MONITORING AND REPORTING PROGRAM

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LIST OF ABBREVIATIONS AND ACRONYMS
2015 EIR Final Environmental Impact Report for the Pure Water Monterey Groundwater Replenishment Project
2021 SEIR Final Supplemental Environmental Impact Report for the Proposed Modifications to the Public Water Monterey Groundwater
Replenishment Project
Addendum No. 1 Addendum to the Aquifer Storage and Recovery Project Environmental Impact Report/ Environmental Assessment and the Pure Water Monterey/Groundwater Replenishment Project
Environmental Impact Report for the Hilby Avenue Pump Station Addendum No. 2 Addendum No. 3 to the Aquifer Storage and Recovery Project Environmental Impact Report/ Environmental Assessment and Addendum No. 2 to the Pure Water Monterey/Groundwater
Replenishment Project Environmental Impact Report for the Monterey Pipeline
Addendum No. 3 Addendum No. 3 to the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Advanced Water Treatment Facility Expanded Capacity Project Modifications
Addendum to the 2021
SEIR
Addendum to the Expanded Pure Water Monterey/Groundwater Replenishment Project Supplemental Environmental Impact Report for the Deep Injection Well #6 Changes
AFY acre-feet per year
BMPs Best Management Practices
CalAm California American Water
CAAQS California Ambient Air Quality Standards
CAL FIRE California Department of Forestry and Fire Protection Caltrans California Department of Transportation
CCWG Central Coast Wetlands Group
CEQA California Environmental Quality Act
CHP California Highway Patrol
City City of Salinas
cfs cubic feet per second
CRLF California red-legged frog
EIR Environmental Impact Report

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GHG greenhouse gas
HCP Habitat Conservation Plan
IPS Influent Pump Station
IWTF Salinas Industrial Wastewater Treatment Facility
IWW Industrial Wastewater Pipeline
LRA Local Responsibility Area
M1W Monterey One Water
M1W Board Monterey One Water Board of Directors
MBARD Monterey Bay Air Resources District
MCWD Marina Coast Water District
mgd millions gallon per day
MMRP Mitigation Monitoring and Reporting Program
MPWMD Monterey Peninsula Water Management District
MRZ Mineral Resource Zone
MS4 Salinas Medium Municipal Separate Storm Sewer System NCCP Natural Conservation Community Plan
NPDES National Pollutant Discharge Elimination System
OHP California Office of Historic Preservation
PG&E Pacific Gas and Electric Company
PM10 particulate matter with a diameter of less than 10 micrometers PWM/GWR Project Pure Water Monterey/Groundwater Replenishment Project Proposed Modifications Proposed Modifications to the Pure Water Monterey Groundwater Replenishment Project
RUWAP Regional Urban Water Augment Project
RWQCB Regional Water Quality Control Board
SRSW Salinas River Subwatershed
SPERSS Salinas Project to Enhance Regional Stormwater Supply SSWMP Salinas Storm Water Management Project
SWPPP Stormwater Pollution Prevention Plan
TACs toxic air contaminants
TP-1 Salinas Treatment Plant No. 1

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USACOE United States Army Corps of Engineers
VHFHSZ Very High Fire Hazard Severity Zone

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1.0 INTRODUCTION
This Addendum prepared pursuant to the California Environmental Quality Act (CEQA) evaluates the potential environmental impacts of the proposed Salinas Project to Enhance Regional Stormwater Supply (SPERSS) Project (SPERSS Project) and the Salinas Storm Water Management Project (SSWMP), which is part of the Pure Water Monterey/Groundwater Replenishment Project (PWM/GWR Project) evaluated in the following documents:
• Final Environmental Impact Report for the Pure Water Monterey Groundwater Replenishment Project (2015 EIR)1
• Addendum to the Aquifer Storage and Recovery Project Environmental Impact Report/ Environmental Assessment and the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Hilby Avenue Pump Station (Addendum No. 1)2 • Addendum No. 3 to the Aquifer Storage and Recovery Project Environmental Impact Report/ Environmental Assessment and Addendum No. 2 to the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Monterey Pipeline (Addendum No. 2)3
• Addendum No. 3 to the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Advanced Water Treatment Facility Expanded Capacity Project Modifications (Addendum No. 3)4
• Final Supplemental Environmental Impact Report for the Proposed Modifications to the Public Water Monterey Groundwater Replenishment Project (2021 SEIR)5

1 Denise Duffy and Associates Inc., Environmental Consultants Resource Planners. 2015. Pure Water Monterey Groundwater Replenishment Project, Final Environmental Impact Report, State Clearinghouse No. 2013051094. October.
2 Denise Duffy and Associates. 2016. Addendum to the Aquifer Storage and Recovery Project Environmental Impact Report/Environmental Assessment and the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Hilby Avenue Pump Station . June 14. 3 Denise Duffy and Associates. 2017. Addendum No. 3 to the Aquifer Storage and Recovery Project Environmental Impact Report/Environmental Assessment and Addendum No. 2 to the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Monterey Pipeline.

February 13.
4 Denise Duffy and Associates. 2017. Addendum No. 3 to the Pure Water Monterey/Groundwater Replenishment Project Environmental Impact Report for the Advanced Water Treatment Facility Expanded Capacity Project Modifications. October 24.
5 Denise Duffy and Associates Inc. 2020. Final Supplemental Environmental Impact Report for the Proposed Modifications to the Pure Water Monterey Groundwater Replenishment Project (SCH# 2013051094). April.

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• Addendum to the Expanded Pure Water Monterey/Groundwater Replenishment Project Supplemental Environmental Impact Report for the Deep Injection Well #6 Changes (Addendum to the 2021 SEIR)6
Collectively, these environmental review documents are referred to as the “prior CEQA documents,” and are described further below.

The SPERSS and SSWMP Projects would improve stormwater capture, storage, and conveyance infrastructure, which will enhance the effectiveness of the PWM/GWR Project while providing water quality benefits in the Salinas area. Improvements proposed as part of the SPERSS Project include the following:
• A new trash capture facility;
• A diversion structure;
• Rehabilitation of an existing 33-inch-diameter pipeline to convey stormwater from the diversion structure to the Salinas Industrial Wastewater Treatment Facility (IWTF); • Construction of a new pump station and upgrades to the existing pump station at the IWTF. • A wetland rehabilitation pilot study.

As described further below, elements of the SPERSS and SSWMP Projects, including the proposed diversion facility and pump station at the IWTF, were described and evaluated as part of the prior CEQA documents. Other elements of the SPERSS and SSWMP Project are new (e.g., trash capture device) or slightly different from the project elements described in the prior CEQA documents.

Details on the changes are included in the Project Description, below.

Per CEQA Section 15164, this Addendum evaluates whether implementation of the PWM/GWR Project, as modified, would result in new or substantially more severe significant effects or require new mitigation measures not identified in the prior CEQA documents. The City of Salinas (City) is both the project proponent and the CEQA Lead Agency for environmental review of the SPERSS and SSWMP Projects.

A Mitigation Monitoring and Reporting Program (MMRP) has been prepared based upon the findings of this Addendum. The MMRP, which is found in Appendix A, lists the mitigation measures from the prior CEQA documents that are applicable to the proposed project and provides mitigation monitoring requirements only for those measures that still apply. This MMRP table is intended to help the City of Salinas ensure compliance with the applicable mitigation measures during implementation of the proposed project.

6 Denise Duffy and Associates Inc. 2021. Addendum to the Expanded Pure Water Monterey/Groundwater Replenishment Project Supplemental Environmental Impact Report (SCH# 2013051094) for the Deep Injection Well #6 Changes. November.

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2.0 PRIOR ENVIRONMENTAL REVIEW
The following describes the prior CEQA documents upon which this Addendum relies.

2.1 2015 EIR
On October 8, 2015, per Board Resolution 2015-24, the Monterey One Water (M1W) Board of Directors (M1W Board) certified the 2015 EIR for the PWM/GWR Project and approved the project as modified by the Alternative Monterey Pipeline and the Regional Urban Water Augment Project (RUWAP) alignment for the Public Water Conveyance pipeline and booster pump station, which were presented and analyzed as alternatives in the 2015 EIR. The PWM/GWR Project would serve northern Monterey County. The purpose of the PWM/GWR Project is to provide: (1) purified recycled water for recharge of a groundwater basin that serves as drinking water supply; (2) purified recycled water for urban landscape irrigation within the Marina Coast Water District (MCWD) service area; and (3) recycled water to augment the existing Castroville Seawater Intrusion Project’s agricultural irrigation supply. The PWM/GWR Project also includes a drought reserve component to support crop irrigation during dry years. M1W is currently implementing the PWM/GWR Project in partnership with both the Monterey Peninsula Water Management District (MPWMD) and MCWD.

The 2015 EIR identified the following significant and unavoidable impacts:
• Impact NV-1 : Construction Noise (Alternatives Monterey Pipeline) • Impact NV-2: Construction Noise that Exceeds or Violates Local Standards (Tembladero Slough) As part of the project approvals, the M1W Board adopted a Mitigation and Monitoring Reporting Program, which outlines the mitigation measures applicable to the SPERSS and SSWMP Projects. The M1W Board also adopted a Statement of Overriding Considerations in connection with its certification of the 2015 EIR.

The PWM/GWR Project, as evaluated in the 2015 EIR, included modifications to existing facilities and construction of new facilities to divert and convey new source waters through the existing municipal wastewater collection system, including:

1. Development of a new diversion structure at the Salinas Treatment Plant No. 1 (TP-1) site;

2. Demolition of the existing pump station at the IWTF;

3. Construction of a new 42-inch industrial wastewater pipeline to replace the existing 33-inch gravity main between the City’s TP-1 site and the IWTF; and

4. Installation of an 18-inch return pipeline within the abandoned 33-inch pipeline to return water from the IWTF to the diversion structure at the TP-1 site.

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2.2 ADDENDA TO THE 2015 EIR
Following certification of the 2015 EIR, three addenda were prepared and approved addressing changes to the PWM/GWR Project.

2.2.1 Addendum #1
Addendum No. 1 evaluated the environmental effects of constructing and operating an additional pump station, the Hilby Avenue Pump Station.

2.2.2 Addendum #2
Addendum No. 2 evaluated the environmental effects of realigning a 0.44-mile (2,350-linear-foot) segment of the Monterey Pipeline from its previous alignment within the existing right-of-way of Lily Street and Hoffman Avenue to a revised alignment along Irvine Avenue and Spencer Street. The revised alignment would begin at the intersection of Lily Street and Irving Avenue and end at the intersection of Spencer Street and Hoffman Avenue.

2.2.3 Addendum #3
Addendum No. 3 evaluated the environmental effects of increasing the peak capacity of the approved Advanced Water Treatment Facility from a maximum capacity of 4.0 million gallons per day (mgd) to 5.0 mgd. During its approval of Addendum No. 3, the M1W Board also approved the joint use of a MCWD conveyance pipeline7 and storage tank (Blackhorse Reservoir) for delivering water to MCWD customers to use as urban landscape irrigation and to the groundwater replenishment injection wells in the Seaside Groundwater Basin.

All three addenda determined that the proposed modifications to the PWM/GWR Project would not result in new impacts or substantially more severe significant impacts than those previously identified in the 2015 EIR.

None of the changes evaluated in these three Addenda are part of the currently proposed SPERSS or SSWMP Projects.

2.3 SUPPLEMENTAL 2021 EIR
In 2021, M1W, as the CEQA Lead Agency, certified the Final Supplemental Environmental Impact Report for the Proposed Modifications to the Public Water Monterey Groundwater Replenishment Project (2021 SEIR)8 and approved the Proposed Modifications to the Pure Water Monterey Groundwater Replenishment Project (Proposed Modifications) on April 26, 2021, per Board Resolution 2021-05.

The primary objectives of the Proposed Modifications were to reduce discharges of secondary effluent to Monterey Bay and to provide approximately 2,250 acre-feet per year (AFY) of additional

7 The MCWD conveyance pipeline is a component of the RUWAP. The RUWAP is an urban recycled water project developed by MCWD.
8 Denise Duffy and Associates Inc . 2020. Final Supplemental Environmental Impact Report for the Proposed Modifications to the Pure Water Monterey Groundwater Replenishment Project (SCH# 2013051094). April.

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purified recycled water for injection into the Seaside Groundwater Basin and subsequent extraction to replace the same quantity of California American Water’s (CalAm) potable water supplies. In order to provide the additional purified recycled water for Seaside Basin injection and subsequent extraction for the CalAm service area, the Proposed Modifications to the PWM/GWR Project included improvements to M1W and CalAm facilities, as described below. • Modifications to M1W Facilities:
○ Improvements to the Advanced Water Purification Facility to increase peak capacity (adding equipment, pipelines, and storage within the approved and constructed facility buildings and paved areas);
○ Up to 2 miles of new water conveyance pipelines;
○ An additional deep injection well; and
○ Relocation of previously approved deep injection wells and monitoring well sites. • Modifications to CalAm Facilities:
○ Four new extraction wells and associated infrastructure (e.g., treatment facilities, electrical building, and pipelines); and
○ New potable and raw water pipelines.

The 2021 SEIR identified the following significant and unavoidable impacts:
• Impact NV-1: Construction Noise
• Secondary Effects of Growth Inducement
As part of the project approvals, the M1W Board adopted a Mitigation and Monitoring Reporting Program, which outlines the mitigation measures applicable to the SPERSS and SSWMP Projects. The M1W Board also adopted a Statement of Overriding Considerations in connection with its certification of the 2021 SEIR. None of the changes evaluated in the 2021 SEIR are part of the currently proposed SPERSS or SSWMP Projects.

2.4 ADDENDUM TO THE 2021 SEIR
On April 26, 2021, M1W approved an Addendum to the 2021 SEIR. The 2021 Addendum analyzed the impacts associated with the following modifications to the PWM/GWR Project:
• The relocation of a previously approved shallow injection well; • A pipeline extension; and
• The relocation of a previously approved backflush basin.

The 2021 Addendum determined that the proposed modifications to the PWM/GWR Project would not result in new impacts or substantially more severe significant impacts previously identified in

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the 2021 SEIR. None of the changes evaluated in the 2021 Addendum are part of the currently proposed SPERSS or SSWMP Projects.

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3.0 PROJECT DESCRIPTION

The following describes the proposed Salinas Project to Enhance Regional Stormwater Supply (SPERSS) Project and the Salinas Storm Water Management Project.

3.1 PROJECT LOCATION
The PWM/GWR Project facilities, including the original and modified project facilities, are located within unincorporated areas of the Salinas Valley in Monterey County and within the cities of Salinas, Marina, Monterey, Pacific Grove, and Seaside. Specifically, the SPERSS and SSWMP Projects would include improvements to the Salinas IWTF located along the west side of Davis Road, just north of where it crosses the Salinas River, TP-1, located at 156 Hitchcock Road in Salinas, and under Hitchcock Road just east of the Hitchcock Road/Davis Road intersection, as described below.

3.2 PROJECT COMPONENTS
• this document as the Hitchcock Road crossing;
Construction of The SPERSS and SSWMP Projects propose improvements to the TP-1 and the IWTF, as described below. The intent of the SPERSS and SSWMP Projects are to improve stormwater capture, storage, and conveyance infrastructure to enhance the effectiveness of the overarching PWM/GWR Project, which would provide water quality benefits in the Salinas area. As outlined above, improvements proposed as part of the SPERSS and SSWMP Projects include the following:
• A new trash capture facility;
• A diversion structure;
• Rehabilitation of an existing 33-inch-diameter pipeline to convey stormwater from the diversion structure to the Salinas IWTF;
• Installation of a siphon to restore continuity of the 33-inch-diameter pipeline that runs below Hitchcock Road just east of the Hitchcock Road/Davis Road intersection, which is being referred to throughout a new pump station and upgrades to the existing pump station at the IWTF; and • A wetland rehabilitation pilot study.

As described above, the new pump station at the IWTF was described and evaluated as part of the prior CEQA documents. New/modified components of the SPERSS and SSWMP Projects that are evaluated in this Addendum include:
• Salinas River Subwatershed Trash Capture Device and Diversion Structure. A trash capture device and a diversion facility, including conveyance piping, metering, and associated infrastructure, would be installed at TP-1 to improve the capacity and quality of stormwater

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transported to the IWTF. The Salinas River Subwatershed (SRSW) trash capture device would treat stormwater flows from the SRSW and support compliance with the Salinas Medium Municipal Separate Storm Sewer System (MS4) National Pollution Discharge System (NPDES) permit by improving water quality of flows discharged to the Salinas River and the IWTF. The proposed trash capture device would consist of a hydrodynamic separator, which allows the stormwater to flow through a swirl unit that removes sediments and other debris. The device would be connected to an existing 48-inch-diameter storm drain pipeline that flows into an existing 72-inch-diameter pipeline that flows into the Salinas Storm Water Pump Station, located at TP-1. As part of ongoing operation/ maintenance activities, vacuum trucks would be used periodically to pump out trash, sediment, oil/grease, and water that has collected at the bottom of the trash capture device.

Specific improvements would include:
○ A diversion structure constructed over the existing 48-inch-diameter storm drain pipeline.

This structure would have two sections separated by a weir wall and would be designed to bypass storm flows above the design storm. The upstream section would divert stormwater to the trash capture device. Return flow from the trash capture device would then enter the downstream section of the diversion structure to be conveyed to the existing stormwater pump station at the TP-1 site.
○ A trash capture device approximately 14 feet in diameter and 30 feet high installed approximately 30 feet below the existing grade. Inflow to this device would be from the upstream section of the diversion structure, and discharge would be diverted to the downstream section of the diversion structure and then to the stormwater pump station located at the TP-1 site.
• Rehabilitation of the 33-Inch-Diameter Pipeline. The SPERSS and SSWMP Projects would include construction of a Segregated Stormwater Diversion Facility near the existing TP-1. The Segregated Stormwater Diversion Facility would be separate from the diversion facility already installed at the TP-1 site. The implementation of the Segregated Stormwater Diversion facility would enable additional diversion of stormwater to the IWTF using an abandoned 33-inch pipeline. Currently, all diverted stormwater flows are combined with industrial wastewater, requiring large-capacity pumping at the Influent Pump Station (IPS) and treatment via the Aeration Basin at the IWTF. The Segregated Stormwater Diversion facility would allow the stormwater to be conveyed to the IWTF separately from industrial wastewater in order to improve the capacity of flows between the TP-1 and the IWTF, better match water quality to treatment methods, and achieve more sustainable and efficient operation of the IWTF. With implementation of the SPERSS Project, stormwater would also be conveyed directly to Percolation Pond 1 at the IWTF, resulting in energy savings and improved operational capacity and flexibility. With implementation of this improvement, the City of Salinas anticipates increasing stormwater capture to the IWTF by an average of 41 AFY and a peak of up to 652 AFY.

Rehabilitating the abandoned 33-inch-diameter pipeline to convey stormwater from the TP-1 to the IWTF represents a change from the PWM/GWR Project. The 33-inch diameter pipeline, which previously conveyed industrial wastewater, was replaced by the 42-inch diameter

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pipeline that was identified and evaluated in the prior CEQA documents. As described in the prior CEQA documents, a new 18-inch return pipeline was to be inserted into the abandoned 33- inch-diameter pipeline; however, the 18-inch-diameter pipeline was never installed inside the 33-inch-diameter pipeline and is no longer being considered.

With implementation of the SPERSS and SSWMP Projects, the 33-inch-diameter pipeline would be rehabilitated for stormwater only and would be used in addition to (not to replace) the existing 42-inch-diameter Industrial Wastewater Pipeline (IWW) to convey stormwater from the TP-1 site to the IWTF.

Rehabilitation of the 33-inch-diameter pipeline would include reconstructing it in areas where it crosses the 42-inch-diameter pipeline, as well as installing new manholes and lowering the pipe so that it can siphon under the new 42-inch-diameter pipeline. In addition, initial field inspections indicated that a section of the 33-inch-diameter pipeline at the Hitchcock Road crossing was removed. Therefore, rehabilitation of the 33-inch-diameter pipeline would also include constructing a siphon at the Hitchcock Road crossing in order to restore the continuity of the 33-inch-diameter pipeline between the TP-1 site and the IWTF. After reconstruction, the 33- inch-diameter pipeline would have a calculated capacity of approximately 7 to 7.5 mgd, or approximately 10.8 to 11.6 cubic feet per second (cfs).

Project elements would include:
○ CCTV inspection and condition assessment of existing 33-inch abandoned IWW pipeline; ○ Rehabilitation of a 33-inch abandoned IWW pipeline based on the results of the CCTV and condition assessment;
○ Construction of manholes and installation of a siphon connection at the Hitchcock Road crossing; and
○ Modifications to the existing diversion structure in front of the existing IPS at the IWTF. • Upgrades to Existing Influent Pump Station. The existing IPS is to be replaced with a new influent pump station and the existing IPS is to be converted to a stormwater pump station. As described above, construction of the new influent pump station was analyzed in the prior CEQA documents and, therefore, is not part of the proposed project that is the subject of this Addendum. Upgrades to the existing IPS include the addition of energy-efficient pumps, raising the existing IPS above the 100-year flood, and connections to the rehabilitated 33-inch pipeline for influent stormwater flow and a new force main to discharge segregated stormwater conveyance directly to IWTF Percolation Pond 1, as described above. Because stormwater does not warrant aeration treatment, this new conveyance scheme will enable stormwater to bypass the Aeration Basin treatment process, saving energy and increasing system capacity for treating and processing stormwater for recycling/reuse.

Currently, the existing pump station electrical components, including motor controls, a transformer, and related instrumentation, are located within the 100-year floodplain, making

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them vulnerable to inundation during large storm events. This equipment would be inundated in a 100-year flood event, rendering the IPS inoperable. In addition, the electrical components are approximately 45 to 50 years old and have reached the end of their useful life. The City of Salinas would make improvements to select IWTF electrical components associated with the IPS, enhancing its flood and climate resilience. All of these existing components would be replaced with new state-of-the-art equipment at a secure location above the 100-year floodplain.

Rehabilitation of the existing IPS would include:
○ Rehabilitating the existing pump station with three stormwater pumps with combined capacity of 9 mgd;
○ Raising the existing perimeter pump station wall above the 100-year flood event; ○ Construction of a new force main from the IPS to percolation Pond No.1 to divert stormwater flows to Percolation Pond No. 1 without any treatment; ○ Construction of a new electrical building to house all electrical/instrumentation equipment above the 100-year flood; and
○ Installation of an emergency generator above the 100-year flood level to provide power during power outages for both the new and existing pump stations. • Wetland Rehabilitation Pilot Study. The Central Coast Wetlands Group (CCWG) is planning to construct an initial water treatment system at the IWTF consisting of a treatment wetland chamber in a series with several pilot phosphate removal chambers. CCWG will then assess the system’s functionality to determine the most cost-effective phosphate removal process.

3.3 CONSTRUCTION
Construction of the proposed improvements are anticipated to commence in August 2024 and extend for approximately 18 months. Construction methodology, equipment, and staging would be the same as identified in the prior environmental documents.

3.4 OPERATIONS AND MAINTENANCE
As described in the prior CEQA documents, the Salinas Pump Station Diversion site is adjacent to and north of the existing TP-1 site and would be maintained by the same M1W operations staff that currently operate TP-1. No additional employee site visits would be required at the TP-1 site. No ongoing materials delivery or solid waste generation would occur. Similarly, the new storage and recovery facilities at the IWTF would be managed by the same number of staff that currently operate the IWTF.

Installation of the trash capture facility would require periodic removal of trash, sediment, oil/grease, and water that has collected at the bottom. It is anticipated that removal would be required several times per year during the rainy season.

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4.0 CEQA FRAMEWORK FOR USE OF AN ADDENDUM

Pursuant to Section 21166 of CEQA and Section 15162 of the State CEQA Guidelines, when an Environmental Impact Report (EIR) has been certified or a Negative Declaration has been adopted for a project, no subsequent EIR shall be prepared for the project unless the lead agency determines, on the basis of substantial evidence, that one or more of the following conditions are met:
• Substantial changes are proposed in the project that will require major revisions of the previous EIR or Negative Declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects. • Substantial changes occur with respect to the circumstances under which the project is undertaken that will require major revisions of the previous EIR or Negative Declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects.
• New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time the previous EIR was certified as complete or Negative Declaration was adopted, shows any of the following:
• The project would have one or more significant effects not discussed in the previous EIR or Negative Declaration.
• Significant effects previously examined would be substantially more severe than identified in the previous EIR.
• Mitigation measures or alternatives previously found not to be feasible would in fact be feasible and would substantially reduce one or more significant effects of the project, but the project proponent declines to adopt the mitigation measures or alternatives. • Mitigation measures or alternatives that are considerably different from those analyzed in the previous EIR would substantially reduce one or more significant effects on the environment, but the project proponent declines to adopt the mitigation measures or alternatives.

Section 15164 of the State CEQA Guidelines states that an Addendum to an EIR or Negative Declaration shall be prepared “if some changes or additions are necessary, but none of the conditions described in Section 15162 calling for preparation of a subsequent EIR have occurred.” Pursuant to State CEQA Guidelines Section 15164(e), this Addendum summarizes the revisions to the PWM/GWR Project, any changes to the existing conditions that have occurred since the prior CEQA documents were approved, any new information of substantial importance that was not known and could not have been known with exercise of reasonable diligence at the time that the prior CEQA documents were approved, and whether, as a result of any changes or any new

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information, a subsequent or supplemental EIR may be required. This examination includes an analysis of the provisions of Section 21166 of CEQA and Section 15162 of the State CEQA Guidelines and their applicability to the SPERSS Project. This Addendum relies on an environmental analysis of the issues listed in Appendix G of the State CEQA Guidelines.

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5.0 EVALUATION OF ENVIRONMENTAL EFFECTS
The following environmental analysis evaluates the potential environmental impacts resulting from the SPERSS and SSWMP Projects as compared to the impacts of the PWM/GWR Project, which was analyzed in the prior CEQA documents, and whether there would be any difference in identified impacts or required mitigation measures from those identified in the prior CEQA documents. The comparative analysis for each of the environmental issues listed below provides the City of Salinas with a factual basis for determining whether changes in the PWM/GWR Project, changes in circumstances, or new information since approval of the prior CEQA documents require additional environmental review or preparation of a subsequent or supplemental EIR. The basis for each finding is explained in the issues-specific analysis provided below. Because the prior CEQA documents organized the impacts of each project component based on the location of the improvements (e.g., the TP-1 site, the IWTF site, and Hitchcock Road), this Addendum takes the same approach. The SRSW trash capture device, the associated diversion structure, and the 33-inch rehabilitated pipeline would be developed at the TP-1 site. Therefore, the discussion of impacts at the TP-1 site provided below reflects the impacts of these improvements. The proposed siphon for the 33-inch rehabilitated pipeline would be constructed at the 33-inch pipeline crossing at Hitchcock Road, approximately 0.36 mile south of the TP-1 site. This area was previously analyzed for construction activities associated with installation of the 42-inch pipeline that was evaluated in the prior CEQA documents and installed as part of the PWM/GWR Project. Because this improvement is similar in nature and extent to improvements proposed the TP-1 site and is associated with rehabilitation of the 33-inch-diameter pipeline, the discussion of impacts associated with the proposed siphon on Hitchcock Road is generally included with the discussion of impacts at the TP-1 site provided below. Where impacts differ between the TP-1 and Hitchcock Road sites, those impacts are so noted. The new IPS, the upgraded IPS, and the wetland rehabilitation pilot study would be developed at the IWTF site. Therefore, the discussion of impacts at the IWTF site provided below reflects the impacts of these improvements.

As described in detail herein, this analysis confirms that the impacts from the SPERSS and SSWMP Projects would be no more severe than those projected to result from implementation of the PWM/GWR Project. The projected impacts of the SPERSS and SSWMP Projects would either be the same as or less than the anticipated levels associated with the PWM/GWR Project, and no new significant impacts would result with implementation of the SPERSS and SSWMP Projects. Therefore, in accordance with Section 15164 of the State CEQA Guidelines, the Addendum to the prior CEQA documents is the appropriate environmental documentation for the SPERSS and SSWMP Projects.

5.1 AESTHETICS
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with aesthetics and visual resources with incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. The TP-1 site is located at 156 Hitchcock Road. This site is referenced in the prior CEQA documents as the Salinas Pump Station Diversion Site. The TP-1

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site, which contains existing public utility/facility uses, is surrounded by agricultural and rural residential land uses. The Salinas River, which is located approximately 1.5 miles to the southwest, is the primary natural feature in the vicinity of the TP-1 site. The TP-1 site is not located within a designated scenic vista or a scenic corridor as defined by the Monterey County General Plan.

Therefore, the prior CEQA documents determined that visual quality of the TP-1 site is considered low. In addition, as State Scenic Highway 68 is located more than 1 mile from the site, prior CEQA documents determined that implementation of the PWM/GWR Project would not substantially impact resources associated with a scenic highway.

The improvements to the TP-1 site proposed by the SPERSS and SSWMP Projects would include installation of a trash capture device and a diversion facility to improve the capacity and quality of stormwater transported to the IWTF, as well as rehabilitation of an abandoned 33-inch-diameter pipeline to enable stormwater to be diverted to the IWTF separately from industrial wastewater. As these improvements would be located on the same TP-1 site analyzed in the prior CEQA documents and summarized above and would be located underground and out of view, these improvements would not impact the aesthetics or surrounding visual character of the TP-1 site. In addition, similar to the PWM/GWR Project, the improvements proposed at the TP-1 site as part of the SPERSS and SSWMP Projects would be underground facilities and pipelines. As such, these improvements would not be visible, and impacts associated with the creation of new sources of substantial light or glare would be less than significant. Therefore, similar to the PWM/GWR Project, aesthetic and visual impacts associated with the SPERSS and SSWMP Projects at the TP-1 site would be less than significant.

The IWTF site is located approximately 1 mile south of the TP-1 site. The existing IWTF site is located adjacent to the Salinas River, downstream of the Davis Road crossing, and is surrounded by agricultural operations to the north, east, and west, with the Salinas River to the south. The IWTF site contains utility-type development as a water and wastewater treatment and conveyance site, but the IWTF site’s visual appearance is largely dominated by the existing percolation ponds that have the appearance of man-made open water. The IWTF site is not located within a designated scenic vista of a scenic corridor as defined by the Monterey County General Plan. Therefore, the prior CEQA documents determined that visual quality of the site is considered low. In addition, as State Scenic Highway 68 is located over 2 miles from the IWTF site, the prior CEQA documents determined that implementation of the PWM/GWR Project would not substantially impact resources associated with a scenic highway. The improvements to the IWTF site proposed by the SPERSS and SSWMP Projects would include construction of a new influent pump station; upgrades to the existing IPS, which would connect to the refurbished 33-inch pipeline for influent stormwater flow and discharge segregated stormwater conveyance directly to IWTF Percolation Pond 1; and installation of a wetland pilot project. As these improvements would be located on the same IWTF site analyzed in the prior CEQA documents, these improvements would be consistent with the existing land uses at the IWTF site and the surrounding visual character. Similar to the PWM/GWR Project, the improvements proposed at the IWTF site as part of the SPERSS and SSWMP Projects would consist of both underground facilities and pipelines and aboveground structures/pumps.

However, the aboveground structures/pumps would be low-profile (i.e., less than 4 feet above ground). After construction is completed, the SPERSS and SSWMP Projects components at the IWTF site that are below ground would not be visible, and those that are aboveground would not have

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permanent lighting installed. As such, similar to the PWM/GWR Project, impacts associated with the creation of new sources of substantial light or glare associated with the SPERSS and SSWMP Projects components at the IWTF site would be less than significant. Therefore, similar to the PWM/GWR Project, aesthetic and visual impacts associated with the SPERSS and SSWMP Projects at the IWTF site would be less than significant.

Based on the information in the prior CEQA documents and this environmental analysis, implementation of the SPERSS and SSWMP Projects would not substantially increase the severity of the previously identified impacts associated with aesthetics or result in new significant impacts.

While the prior CEQA documents did prescribe Mitigation Measures AE-2 through AE-4 to reduce impacts on aesthetics and visual resources associated with the PWM/GWR Project, these mitigation measures were not prescribed for project components at the TP-1 and the IWTF sites. Therefore, mitigation measures prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Aesthetics:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No existing mitigation measures would apply, and no new mitigation measures would be required.

5.2 AGRICULTURE AND FORESTRY RESOURCES
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with agriculture and forestry resources with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. In the prior CEQA documents, impacts on agriculture and forestry resources were analyzed as part of the discussion of impacts associated with land use and planning. As such, Section 5.11, Land Use, of this Addendum provides the comparative analysis for impacts associated with agriculture and forestry resources.

5.3 AIR QUALITY
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with air quality with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

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Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents indicated that the North Central Coast Air Basin, which includes Monterey, Santa Cruz, and San Benito counties, is considered a nonattainment area for the California Ambient Air Quality Standards (CAAQS) for ground-level ozone and particulate matter with a diameter of less than 10 micrometers (PM10). The prior CEQA documents determined that while construction of individual PWM/GWR Project components would not have a significant impact on air quality, construction of the PWM/GWR Project as a whole would result in emissions of criteria pollutants, specifically PM10, that may conflict with or obstruct implementation of the applicable air quality plan, violate an air quality standard, or contribute substantially to an existing or projected air quality violation in a region that is designated as nonattainment under CAAQS. As such, the prior CEQA documents prescribed Mitigation Measure AQ-1, which requires that a construction fugitive dust control plan be implemented during construction activities to ensure emissions of PM10 would be reduced to below the Monterey Bay Air Resources District (MBARD) emission thresholds. Therefore, similar to the PWM/GWR Project, with implementation of Mitigation Measure AQ-1, the SPERSS and SSWMP Projects would have a less than significant impact associated with construction criteria pollutant emissions, specifically PM10, for which the State is in nonattainment.

The prior CEQA documents determined that the PWM/GWR Project would not result in any new stationary sources of air pollutant emissions during operation and emissions of criteria pollutants from operational traffic would be below the thresholds adopted by MBARD for evaluating impacts related to ozone and PM10. As such, the prior CEQA documents determined that the PWM/GWR Project would not result in a net increase of criteria pollutants or contribute considerably to existing or projected violations of air quality standards pertaining to ozone or PM10. In addition, the prior CEQA documents determined that due to the minimal traffic associated with operation of the PWM/GWR Project, implementation of the PWM/GWR Project would not cause a carbon monoxide violation at surrounding intersections. Implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with similar uses as analyzed in the prior CEQA documents and would not introduce any new stationary sources of air pollutant emissions during operation. In addition, as discussed in Section 5.17, Transportation, operational traffic would be minimal, similar to the PWM/GWR Project. Therefore, similar to the PWM/GWR Project, operation of the SPERSS and SSWMP Projects would not result in a net increase of criteria pollutants or contribute considerably to existing or projected violations of air quality standards pertaining to ozone or PM10.

In addition, similar to the PWM/GWR Project, the small amount of project-related traffic would not substantially affect carbon monoxide levels and operation of the SPERSS and SSWMP Projects would not have the potential to cause a carbon monoxide violation at surrounding intersections.

The prior CEQA documents identified the nearest sensitive receptor to the TP-1 site as the farmhouse on Blanco Road located approximately 1,400 to 2,000 feet away, and the nearest sensitive receptors to the IWTF site as residences across David Road approximately 2,500 feet away.

As detailed in the prior CEQA documents, the PWM/GWR Project would expose sensitive receptors to temporary emissions of toxic air contaminants (TACs) during construction activities, with the primary concern being exposure to diesel particulate matter emissions associated with operation of diesel-powered construction equipment and trucks. However, based on the MBARD screening criteria for TAC impacts from construction projects, the prior CEQA documents determined that construction activities would not expose sensitive receptors to significant levels of TACs. In addition,

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although there may be intermittent odors associated with diesel exhaust during project construction that could be noticeable at residences in close proximity to the TP-1 and IWTF sites, the prior CEQA documents determined that given the distance of the sensitive receptors from the construction sites and the temporary nature of the construction activities, potential odors from construction equipment would not affect a substantial number of people. Therefore, similar to the PWM/GWR Project, construction of the SPERSS and SSWMP Projects would not expose sensitive receptors to substantial pollutant concentrations or significant odors.

The prior CEQA documents determined that operation of the PWM/GWR Project would not result in emissions of TACs that could affect nearby sensitive receptors as the PWM/GWR Project would not have any direct sources of operational TAC emissions and vehicle and truck traffic generated by the PWM/GWR Project would be minimal. In addition, the prior CEQA documents determined that improvements at the IWTF site would not generate odors beyond those currently present at the site and frequent objectionable odors would not occur at the TP-1 site due to the nature of the proposed improvements (e.g., underground diversion structures and pipes). Implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with similar uses as analyzed in the prior CEQA documents and would not introduce any new direct sources of operational TAC emissions or new objectionable odors. In addition, as discussed in Section 5.17, Transportation, similar to the PWM/GWR Project, operational traffic associated with the SPERSS and SSWMP Projects would be minimal. Therefore, similar to the PWM/GWR Project, operation of the SPERSS and SSWMP Projects would not result in emissions of TACs or significant odors that could affect nearby sensitive receptors.

Based on the information in the prior CEQA documents and this environmental analysis, implementation of the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on air quality nor result in new significant impacts. With implementation of Mitigation Measure AQ-1, there would be no new impacts or increase in severity of impacts related to air quality.

Findings Related to Air Quality:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measure AQ-1 would apply, and no new mitigation measures would be required.

5.4 BIOLOGICAL RESOURCES
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts on fisheries and terrestrial biological

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resources with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects.

Fisheries. The prior CEQA documents identified both the TP-1 and IWTF sites as located in proximity to aquatic resources that may support fisheries. The prior CEQA documents also indicated that operation of the PWM/GWR Project would potentially alter fish habitat conditions as flows would be diverted at certain locations, at various times of the year, and in varying amounts in the Salinas River, Reclamation Ditch, and Tembladero Slough. These changes in flow could impact steelhead trout, tidewater goby, and Monterey roach habitat and populations. As such, the prior CEQA documents prescribed Mitigation Measures BF-1a through BF-1c for implementing improvements at the Reclamation Ditch and Tembladero Slough Diversion sites to reduce impacts to less than significant levels. These mitigation measures did not apply to the TP-1 and IWTF sites. The prior CEQA documents also prescribed Mitigation Measure BT-1a, which requires the implementation of construction best practices for construction of all PWM/GWR Project components in order to address impacts on aquatic and terrestrial ecosystems. Although the SPERSS and SSWMP Projects also include a new diversion structure and trash capture facility at the TP-1 site and pump station improvements at the IWTF, these facilities would improve stormwater capture, storage, and conveyance infrastructure and would not divert additional flows from the Salinas River, Reclamation Ditch, or Tembladero Slough. Therefore, implementation of the SPERSS and SSWMP Projects would not impact steelhead trout and tidewater goby populations or their habitats and Mitigation Measures BF- 1a through BF-1c would not apply. However, Mitigation Measure BT-1a is applicable to the SPERSS Project. Therefore, similar to the PWM/GWR Project, with implementation of Mitigation Measure BT-1a, the SPERSS and SSWMP Projects would not result in significant impacts associated with habitat modification.

The prior CEQA documents determined that operation of the PWM/GWR Project would result in changes in stream flows that may interfere with fish migration in the Salinas River and Reclamation Ditch. Specifically, PWM/GWR Project components at the TP-1 and IWTF sites would reduce flows in the Salinas River by diverting stormwater and IWTF inflow, and PWM/GWR Project components associated with the Reclamation Ditch Diversion would affect flows in the Reclamation Ditch. The prior CEQA documents determined that operation of the PWM/GWR Project would divert less than 2 percent of the baseline mean annual low in the Salinas River. In addition, the modeling analysis results show that under the PWM/GWR Project, suitable adult migration flows would be reduced below each of the passage flow indicator values less than 2 percent of the time and juvenile migration flows would be reduced below each of the passage flow indicator values less than 3 percent of the time, both relative to existing conditions. Although the percent of flow reductions would vary by month for all indicator flows, changes in flow within any month would be less than 6.7 percent with the highest change in December. Overall, modeling analysis performed in the prior CEQA documents indicated that the change in flow with implementation of the PWM/GWR Project would not result in significant impacts to steelhead migration in the Salinas River.

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The stormwater diversion structure proposed as part of the SPERSS and SSWMP Projects would enable additional diversion of stormwater to the IWTF using the rehabilitated 33-inch-diameter pipeline. Currently, all diverted stormwater flows are combined with industrial wastewater, requiring large-capacity pumping at the IPS and treatment via the Aeration Basin at the IWTF.

The diversion facility would allow the stormwater to be conveyed to the IWTF separately from industrial wastewater in order to improve the capacity of flows between the TP-1 and the IWTF, better match water quality to treatment methods, and achieve more sustainable and efficient operation of the IWTF. By separating the stormwater flows from the industrial wastewater, the IWTF would be able to treat more stormwater than under existing conditions. The treated stormwater would then be conveyed to the M1W system to be recycled rather than discharged into the Salinas River. As such, there may be a reduction in flows to the Salinas River given the increased capacity of the new stormwater capture and conveyance infrastructure.

Implementation of the SPERSS and SSWMP Projects is anticipated to capture an additional 41- AFY. This additional runoff capture is within the total watershed runoff capture assumed in the prior CEQA documents. Therefore, implementation of the SPERSS and SSWMP Projects would not result in a reduction of flows to the Salinas River beyond what was analyzed and discussed in the prior CEQA documents. As the prior CEQA documents determined that the reduction in flows to the Salinas River would result in less than significant impacts on steelhead migration, implementation of the SPERSS and SSWMP Projects would also result in less than significant impacts to steelhead migration in the Salinas River.

Implementation of the SPERSS and SSWMP Projects would not involve any work associated the Reclamation Ditch Diversion. Therefore, impacts on fish migration due to affected flows in the Reclamation Ditch would remain the same as discussed in the prior CEQA documents. The prior CEQA documents identified Mitigation Measures BF-2a and BF-2b to maintain migration flows in the Reclamation Ditch and modify the existing San Jon weir to provide for steelhead passage; however, these measures were not prescribed for project components at the TP-1 and the IWTF sites and would not apply to the SPERSS Project.

The prior CEQA documents determined that operation of the PWM/GWR Project would not result in a reduction of fish habitat or populations. As discussed above, the prior CEQA documents determined that changes to flows in the Salinas River would occur with operation of the improvements at the TP-1 and IWTF sites; however, it was determined that this impact would be less than significant. Further, the prior CEQA documents determined that operation of the PWM/GWR Project would not result in a significant impact on water quality in the Salinas River. Although the SPERSS and SSWMP Project includes a new diversion structure and trash capture facility at the TP-1 site and pump station improvements at the IWTF, these facilities would improve stormwater capture, storage, and conveyance infrastructure to enhance the effectiveness of the PWM/GWR Project and would not divert additional flows from the Salinas River. In addition, implementation of the SPERSS and SSWMP Projects would not result in a reduction of flows to the Salinas River beyond what was analyzed and discussed in the prior CEQA documents. Therefore, similar to the PWM/GWR Project, no additional impacts associated with a reduction of fish habitat, populations, or water quality would occur with implementation of the SPERSS and SSWMP Projects.

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The prior CEQA documents determined that construction and operation of the PWM/GWR Project would not result in conflicts with local policies addressing protection of fishery resources or conflict with any Habitat Conservation Plan (HCP) or Natural Conservation Community Plan (NCCP) as no HCP or NCCP has been adopted in the area. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, similar to the PWM/GWR Project, the SPERSS and SSWMP Projects would not result in conflicts with local policies addressing protection of fishery resources or conflict with any HCP or NCCP.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on fisheries nor result in new significant impacts. With implementation of Mitigation Measure BT-1a, as discussed above, there would be no new or substantially more severe significant impacts related to fisheries.

While the prior CEQA documents did prescribe Mitigation Measures BF-1a through BF-1c, BF- 2a, and BF-2b to reduce impacts on fisheries, these mitigation measures were not prescribed for project components at the TP-1 and the IWTF sites. Therefore, Mitigation Measures BF-1a through BF-1c, BF-2a, and BF-2b prescribed for the PWM/GWR Project would not apply to the SPERSS Project.

Terrestrial. The prior CEQA documents identified the TP-1 site as consisting of 35.9 acres of ruderal/developed/active agriculture land and the IWTF site as consisting of 6.4 acres of ruderal/developed/active agriculture land, 244.1 acres of wastewater ponds, and 34.7 acres of riparian habitat. No special status plant species were observed at either the TP-1 or IWTF sites.

As no special-status plant species were observed at the TP-1 or IWTF sites and none are expected to occur, the prior CEQA documents determined that no impacts to special-status plant species would occur during construction at either of these sites.

Mature trees present on both of the sites may provide suitable habitat for roosting bat species and nesting raptors, migratory birds, or other protected avian species. No other suitable habitat for special-status wildlife occurs at the TP-1 site. In order to reduce potential impacts to roosting bat species and nesting raptors, migratory birds, or other protected avian species that may utilize existing mature trees on both the TP-1 and IWTF sites, the prior CEQA documents prescribed Mitigation Measures BT-1b, BT-1g (pre-construction surveys for special-species bats), and BT-1k (pre-construction surveys for protected avian species) to reduce impacts to less than significant.

Although no suitable upland habitat or breeding habitat occurs within the IWTF site, the IWTF site is located adjacent to the Salinas River, where the California red-legged frog (CRLF) is known to occur. Therefore, the prior CEQA documents prescribed Mitigation Measure BT-1b, which requires monitoring by a qualified biologist monitor for all ground-disturbing construction activities, and Mitigation Measure BT-1q, which includes measures to avoid and minimize impacts to CRLF.

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The prior CEQA documents determined that although the riparian habitat at the IWTF site could support special-status wildlife species and is considered a sensitive habitat, no impacts to any other special-status wildlife species or direct impacts to riparian habitat would occur because construction activities at the IWTF site would be conducted on the eastern side of the wastewater ponds, more than 200 feet from the riparian habitat.

Therefore, implementation of the SPERSS and SSWMP Projects would result in similar construction and operational impacts associated with special-status species and sensitive habitat as the PWM/GWR Project. In addition, similar to the PWM/GWR Project, no impact to riparian habitat would occur with implementation of the SPERSS and SSWMP Projects.

Similar to the PWM/GWR Project, Mitigation Measures BT-1b, BT-1g, BT-1k, and BT-1q would apply to the SPERSS and SSWMP Projects to reduce potential impacts on special-status species to less than significant levels. The prior CEQA documents also prescribed Mitigation Measures BT-1a (as described in Fisheries above) and BT-1c, which requires the implementation of nonnative, invasive species controls to further reduce construction impacts on biological resources. These measures would also apply to the SPERSS and SSWMP Projects.

Neither the TP-1 or IWTF sites were identified in the prior CEQA documents as being located within documented wildlife corridors or native wildlife nurseries. As such, the prior CEQA documents determined that no impacts to the movement of native wildlife or to native wildlife nursery sites would occur during construction or operation of the PWM/GWR Project. The prior CEQA documents also determined that construction and operation of the PWM/GWR Project would not result in conflicts with local policies, ordinances, or an adopted HCP. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would not impact the movement of native wildlife or native wildlife nursery sites or conflict with local policies, ordinances, or an adopted HCP.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS Project would neither substantially increase the severity of the previously identified impacts on terrestrial biological resources nor result in new significant impacts. With implementation of Mitigation Measures BT-1a, BT-1b, BT-1c, BT-1g, BT-1k, and BT-1q, as discussed above, there would be no new or substantially more severe significant impacts related to terrestrial biological resources.

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While the prior CEQA documents did prescribe Mitigation Measures BT-1d through BT-1f, BT- 1h through BT1-j, BT-1l through BT1-p, BT-2a through BT-2c, and BT-6 to reduce impacts on terrestrial biological resources, these mitigation measures were not prescribed for project components at the TP-1 and IWTF sites. Therefore, Mitigation Measures BT-1d through BT-1f, BT-1h through BT1-j, BT-1l through BT1-p, BT-2a through BT-2c, and BT-6 prescribed for the PWM/GWR Project would not apply to the SPERSS Project.

Findings Related to Biological Resources:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measures BT-1a, BT-1b, BT-1c, BT-1g, BT-1k, and BT-1q would apply, and no new mitigation measures would be required.

5.5 CULTURAL RESOURCES
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with cultural resources with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents identified no historical resources at either the TP-1 or IWTF sites. Therefore, the prior CEQA documents determined that no impacts to historical resources would occur with implementation of the PWM/GWR Project. As the SPERSS Project would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, similar to the PWM/GWR Project, no impacts to historical resources would occur with implementation of the SPERSS Project.

Based on background research through the California Historic Resources Information System and the Native American Heritage Commission and the findings of the field survey and previous surveys undertaken within the PWM/GWR Project area, the prior CEQA documents determined that neither the TP-1 nor IWTF sites contain recorded or known archaeological resources or human remains.

However, the prior CEQA documents indicated that there is a possibility for inadvertent discovery of previously unknown resources, including human remains, during any portion of project construction. As such, the prior CEQA documents prescribed Mitigation Measure CR-2b, detailing measures to address the inadvertent discovery of archaeological resources or human remains, and Mitigation Measure CR-2c, requiring that all listed Native American contacts be notified of any and all discoveries. As the SPERSS Project would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, implementation of the SPERSS and SSWMP Projects would result in similar impacts to archaeological resources as the PWM/GWR Project. Therefore, similar to

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the PWM/GWR Project, Mitigation Measures CR-2b and CR-2c would apply to the SPERSS and SSWMP Projects to reduce potential impacts on the inadvertent discovery of archaeological resources or human remains to less than significant levels.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on cultural resources nor result in new significant impacts. With implementation of Mitigation Measures CR-2b and CR-2c, as discussed above, there would be no new or substantially more severe significant impacts related to cultural resources.

While the prior CEQA documents did prescribe Mitigation Measure CR-1, which requires an avoidance and vibration monitoring plan for pipeline installation in the Presidio of Monterey Historic District and Downtown Monterey, and Mitigation Measure CR-2a, which details the specific archaeological monitoring plan applicable to the Montrey Pipeline segment of the CalAm Distribution System, these mitigation measures were not prescribed for project components at the TP-1 and IWTF sites. Therefore, Mitigation Measures CR-1 and CR-2a prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Cultural Resources:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measures CR-2b and CR-2c would apply, and no new mitigation measures would be required.

5.6 ENERGY
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with energy with the incorporation of mitigation, as discussed in more detail in the comparative analysis, below.

Analysis of the SPERSS and SSWMP Projects. As discussed in the prior CEQA documents, construction of the PWM/GWR Project would consume fuel energy used by construction vehicles and equipment and bound energy found in construction materials, such as asphalt, steel, concrete, pipes, and manufactured or processed materials such as lumber and glass. Fossil fuels would be used during site clearing, grading, trenching, and construction. However, fuel energy consumed during construction would be temporary and would not represent a significant demand on energy resources. The prior CEQA documents also indicated that energy consumption for construction would not result in long-term depletion of nonrenewable energy resources and would not

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permanently increase reliance on energy resources that are not renewable. In addition, the prior CEQA documents determined that the PWM/GWR Project would not conflict with existing energy standards. As the construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents, construction of the SPERSS and SSWMP Projects would result in similar energy use during construction activities as the PWM/GWR Project. Similar to the PWM/GWR Project, construction of the SPERSS and SSWMP Projects would not result in long-term depletion of nonrenewable energy resources, permanently increase reliance on energy resources that are not renewable, or conflict with applicable energy standards.

The prior CEQA documents determined that construction of the PWM/GWR Project could result in the wasteful or inefficient use of energy if construction equipment is not maintained or if haul trips are not planned efficiently. Therefore, the prior CEQA documents prescribed Mitigation Measure EN-1, which requires the preparation of a Construction Equipment Efficiency Plan that identifies specific measures to be implemented to increase the efficient use of construction equipment.

Similar to the PWM/GWR Project, Mitigation Measure EN-1 would apply to the SPERSS and SSWMP Projects and would ensure impacts associated with energy use during construction would be less than significant.

The operation and maintenance of the PWM/GWR Project would result in the ongoing consumption of energy, primarily the use of electricity for pumps, treatment processes, lighting, automated controls, and maintenance equipment. The prior CEQA documents determined that energy demands would be met by the existing Pacific Gas and Electric Company (PG&E) grid. Specifically, the improvements at the TP-1 and IWTF site would be served by local PG&E electricity and distribution systems and would not require a new PG&E utility connection. In addition, the TP-1 site would receive a large portion of its power from solar technologies that the City would purchase. Overall, because the electrical power would be provided directly from the PG&E grid (which has adequate capacity to supply the PWM/GWR Project demands), the existing treatment facilities are partially powered by solar energy and cogeneration of biogas, the PWM/GWR Project would be designed to be energy-efficient, and the energy resources that would be consumed would be for the public benefit, the prior CEQA documents determined the operational energy impact of the PWM/GWR Project would be less than significant. As the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with uses similar to those analyzed in the prior CEQA documents and would not introduce any new, energy-intensive facilities at the sites, the energy consumption of the SPERSS and SSWMP Projects would be similar to the PWM/GWR Project. Therefore, similar to the PWM/GWR Project, the impacts associated with operational energy use would be less than significant.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on energy nor result in new significant impacts. With implementation of Mitigation Measure EN-1, as discussed above, there would be no new or substantially more severe significant impacts related to energy.

Findings Related to Energy:

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1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measure EN-1 would apply, and no new mitigation measures would be required.

5.7 GEOLOGY AND SOILS
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with geology and soils with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents determined that construction of the PWM/GWR Project would not result in substantial soil erosion or the loss of topsoil. Specifically, at the TP-1 site, the prior CEQA documents determined that given the limited area of disturbance (less than 0.25 acre) and the location of the TP-1 site within an area of low erosion hazard, construction at the TP-1 site would not result in significant erosion or loss of topsoil.

The IWTF site is also located within an area of low erosion hazard; however, due to the larger area of disturbance (approximately 3 acres) and the IWTF site’s proximity to the Salinas River, the prior CEQA documents determined that grading, pipeline installation, and other ground-disturbing activities would result in potentially significant erosion impacts. As discussed below in Section 5.10, Hydrology and Water Quality, construction at the IWTF site would require approval of a grading permit and implementation of the Stormwater Pollution Prevention Permit (SWPPP), which would ensure that erosion and loss of topsoil impacts would be less than significant.

Construction associated with the SPERSS and SSWMP Projects would occur at both the TP-1 and IWTF sites. The rehabilitation of the 33-inch-diameter pipeline would also include the construction of a siphon at the Hitchcock Road crossing in order to restore continuity of the 33-inch-diameter pipeline between the TP-1 site and the IWTF. The SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, and construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents. In addition, although implementation of the SPERSS and SSWMP Projects would require the construction of a siphon at the Hitchcock Road crossing, potential impacts associated with activities at the Hitchcock Road crossing were included in the prior CEQA documents. The prior CEQA documents did not identify any significant impacts associated with construction or operation at this location. Therefore, implementation of the SPERSS and SSWMP Projects would result in similar impacts related to erosion and loss of topsoil as the PWM/GWR Project. Similar to the PWM/GWR Project, construction at the TP-1 site would not result in significant erosion or loss of topsoil, and with the approval of a grading permit and implementation of a SWPPP consistent with regulatory requirements, soil erosion or the loss of topsoil due to construction at the IWTF site would be less than significant.

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The prior CEQA documents determined that that exposure to, or creation of, soil stability hazards would not result in a significant impact at either the TP-1 or IWTF sites. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, and construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would not result in impacts associated with unstable geologic units or soil. Therefore, impacts associated with soil collapse or exposure to, or creation of, soil stability hazards during construction and implementation of the SPERSS and SSWMP Projects would be less than significant.

As identified in the prior CEQA documents, neither the TP-1 site nor the IWTF site are located in the vicinity of known, active, or potentially active fault traces or zones. Therefore, the prior CEQA documents determined that no impacts would result from fault rupture at these sites. However, the prior CEQA documents determined that all PWM/GWR Project components would be located within a seismically active region and an earthquake on local or regional faults could result in damage to structures and pipelines due to seismic shaking and/or liquefaction. Further, the TP-1 and IWTF sites are located within areas of high liquefaction susceptibility. Generally, the prior CEQA documents concluded that damages to facilities would be localized and minimized with adherence to local regulations, building codes, and recommendations of site-specific geotechnical reports. The application of applicable seismic design criteria associated with standard engineering practices, as recommended in project-specific geotechnical reports, would further ensure that the facilities would be designed and built to minimize the risk of damage. Although damage from an earthquake could result in temporary cessation of PWM/GWR Project operations until repairs are completed, the prior CEQA documents determined that the effects of seismic ground shaking and liquefaction would not result in a substantial risk of loss, injury, or death resulting in a significant impact. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would not expose people or structures to substantial risk of adverse effects due to fault rupture at these sites. Because the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with uses similar to those analyzed in the prior CEQA documents, damage from an earthquake would also be localized and minimized with adherence to local regulations, building codes, and recommendations of site-specific geotechnical reports. Similar to the PWM/GWR Project, although damage from an earthquake could result in temporary cessation of project operations until repairs are completed, effects of seismic ground shaking and liquefaction would not result in a substantial risk of loss, injury, or death resulting in a significant impact.

The prior CEQA documents determined that there is the potential for soil types at the TP-1 and IWTF sites that exhibit expansive and corrosive properties. The prior CEQA documents described that detailed site-specific geotechnical engineering studies, including subsurface exploration and laboratory testing, would be performed during project design to further assess site soils and provide design details for facility plans in response to soil conditions. Implementation of recommendations in the geotechnical studies would ensure that impacts associated with expansive and corrosive soils would be less than significant. As the SPERSS and SSWMP Projects would be implemented at the TP- 1 and IWTF sites, which were analyzed in the prior CEQA documents, and project-specific geotechnical engineering studies would be performed during project design that would include

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recommendations to address expansive soils, similar to the PWM/GWR Project, impacts would be less than significant.

The prior CEQA documents analyzed impacts related to paleontological resources during construction of the PWM/GWR Project and identified less than significant impacts. The prior CEQA documents indicated that the TP-1 site is within an area mapped by the County as having a low potential for discovery of paleontological resources. While the IWTF site was identified as being located within an area with the potential for discovery of paleontological resources, because the PWM/GWR Project components would be constructed within a limited extent of the Monterey Formation, within previously disturbed rights-of-way consisting of fill materials or previously disturbed materials, impacts to known paleontological resources would be less than significant. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, and construction of the SPERSS and SSWMP Projects improvements at the IWTF site would not require substantial excavation beyond what was analyzed and discussed in the prior CEQA documents, similar to the PWM/GWR Project, impacts on known paleontological impacts from implementation of the SPERSS and SSWMP Projects would be less than significant.

While the prior CEQA documents did prescribe Mitigation Measure GS-5 to address impacts to a segment of the CalAm Distribution Pipeline (Monterey Pipeline) along Del Monte Boulevard that could become exposed due to projected sea level rise and associated coastal erosion, this mitigation measure was not prescribed for project components at the TP-1 and IWTF sites. Therefore, Mitigation Measure GS-5 prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Geology and Soils:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No existing mitigation measures would apply, and no new mitigation measures would be required.

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5.8 GREENHOUSE GAS EMISSIONS
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with greenhouse gas (GHG) emissions, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents determined that construction and operation for the PWM/GWR Project would generate GHG emissions; however, these emissions would not exceed applicable significance thresholds and would not result in a considerable contribution to significant cumulative impacts of GHG emissions and the related global climate change impacts. In addition, the PWM/GWR Project was found to not conflict with any applicable plan, policy, or regulation adopted for the purpose of reducing GHG emissions, as the PWM/GWR Project would not conflict with provisions or implementation of the State Scoping Plan.

As implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with similar uses as those analyzed in the prior CEQA documents and would not include a new source of substantial GHG emissions, construction and operation of the SPERSS and SSWMP Projects would not result in GHG emissions impacts.

Findings Related to Greenhouse Gas Emissions:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No mitigation measures were prescribed in prior CEQA documents, and no new mitigation measures would be required.

5.9 HAZARDS AND HAZARDOUS MATERIALS
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with hazards and hazardous materials with the incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Project. The prior CEQA documents determined that although construction of the PWM/GWR Project would involve the use of hazardous materials (primarily petroleum products such as gasoline, diesel fuels, lubricants, and cleaning solvents), the transport

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and use of these hazardous materials would be required to comply with existing and future hazardous materials law and regulations set by the California Department of Transportation (Caltrans) and the California Highway Patrol (CHP). As such, the prior CEQA documents determined that the potential to create a significant hazard to the public or the environment relating to the routine use, transport, and disposal of hazardous materials during construction would be less than significant. As construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents, implementation of the SPERSS and SSWMP Projects would transport and use similar hazardous materials during construction as the PWM/GWR Project. As with the PWM/GWR Project, the transport and use of these hazardous materials would be required to comply with existing and future hazardous materials law and regulations set by Caltrans and the CHP. In addition, the prior CEQA documents indicated that the operation of proposed improvements at the TP-1 and IWTF sites would not include the routine storage or use of hazardous materials, except for minimal amounts of fuel and lubricants. As implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with uses similar to those analyzed in the prior CEQA documents, the operation of the SPERSS Project would result in similar use of hazardous materials. Therefore, similar to the PWM/GWR Project, impacts associated with the routine use, transport, and disposal of hazardous materials during construction and operation of the SPERSS and SSWMP Projects would be less than significant.

The prior CEQA documents identified two types of hazardous material releases that could occur during construction, including the accidental release of hazardous materials that are routinely used during construction activities and the potential for construction activities to encounter contaminated soil or groundwater at the site. As discussed in the prior CEQA documents, the construction contractors would be required to prepare and implement a SWPPP for construction activities in accordance with the NPDES Construction General Permit requirements, which would include measures for preventing spills, inspecting equipment, and fuel storage. With implementation of a SWPPP, the prior CEQA documents determined that potential impacts associated with the accidental release of hazardous material that are routinely used during construction activities would be less than significant. As discussed below in Section 5.10, Hydrology and Water Quality, construction of the SPERSS and SSWMP Projects would also be required to prepare and implement a SWPPP for construction activities in accordance with the NPDES Construction General Permit. Similar to the PWM/GWR Project, with the applicable hazardous materials storage and stormwater permitting regulations, impacts from the potential release of hazardous materials routinely used during construction activities for the SPERSS and SSWMP Projects would be less than significant.

In order to assess the existing hazardous conditions at the construction sites, the prior CEQA documents identified a list of environmental cases compiled pursuant to Government Code Section 65962.5. The database search did not identify any hazardous materials release sites within 0.25 mile of either the TP-1 or IWTF sites. As such, the prior CEQA documents determined that the potential for construction activities to encounter contaminated soil or groundwater at the sites would be less than significant, and the construction and operation of improvements at these sites would not occur on a known hazardous materials site pursuant to Government Code Section 65962.5. The prior CEQA documents also identified no schools within 0.25 mile of either site. Because the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the

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prior CEQA documents, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would result in less than significant impacts associated with the accidental release of hazardous materials at the site and would not occur on a known hazardous materials site pursuant to Government Code Section 65962.5. In addition, similar to the PWM/GWR Project, the construction at the TP-1 and IWTF sites would neither result in nor create a significant hazard to the public or the environment due to the handling of hazardous materials within 0.25 mile of the school.

While the prior CEQA documents did prescribe Mitigation Measures HH-2a through HH-2c, which require the preparation of a Phase I Environmental Site Assessment, Health and Safety Plan, and Materials and Dewatering Disposal Plan, these mitigation measures were not prescribed for project components at the TP-1 and IWTF sites. Therefore, mitigation measures prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Hazards and Hazardous Materials:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No existing mitigation measures would apply, and no new mitigation measures would be required.

5.10 HYDROLOGY AND WATER QUALITY
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts on groundwater hydrology and water quality, and less than significant impacts on surface water hydrology and water quality with incorporation of mitigation, as discussed in more detail in the comparative analysis below. The prior CEQA documents also identified two beneficial impacts with operation of the PWM/GWR Project:
increased groundwater quality in the Salinas Valley Groundwater Basin and increased marine water quality.

Analysis of the SPERSS and SSWMP Projects.

Groundwater. The prior CEQA documents indicated that construction of the PWM/GWR Project would result in the limited, temporary use of water, primarily for compaction and dust control.

This water would be supplied from either the Salinas Valley Reclamation Plant, when it is experiencing a surplus of water needed for agriculture demands, or groundwater stored

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beneath the Regional Wastewater Treatment Plant site. The prior CEQA documents determined that because of the limited amount of water needed and the temporary nature of the use, the use of water during construction would not have a significant adverse impact on groundwater recharge, volume, or levels. As construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents and would require a similar amount of water for compaction and dust control as the PWM/GWR Project, the use of water during construction of the SPERSS and SSWMP Projects would not have a significant adverse impact on groundwater recharge, volume, or levels.

The prior CEQA documents also determined that although some water would be used during construction, the amount of water to be used at the TP-1 and IWTF sites would not infiltrate the subsurface in significant quantities or carry substantial concentrations of pollutants to groundwater. In addition, as construction of the PWM/GWR Project components would result in the disturbance of more than 1 acre of the site, the construction contractors would be required to implement a SWPPP for construction activities in accordance with the NPDES Construction General Permit requirements. With the implementation of a SWPPP (including best management practices [BMPs]), during construction at both the TP-1 and IWTF sites, the prior CEQA documents determined that impacts associated with groundwater quality would be less than significant. As construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents and would be required to adhere to regulatory requirements, including the preparation and implementation of a SWPPP, similar to the PWM/GWR Project, impacts associated with groundwater quality during construction of the SPERSS and SSWMP Projects would be less than significant.

As discussed in the prior CEQA documents, implementation of the PWM/GWR Project components at the TP-1 and IWTF sites would alter the operation of the IWTF in terms of the amounts and types of water stored at the facility. These changes would alter the quantity and quality of percolation at the sites, which would affect the quantity and quality of the Salinas River and groundwater recharge in the Salinas Valley Groundwater Bains. However, the prior CEQA documents determined that local changes in recharge and water levels, as well as effects on nearby wells, would be less than significant due to the diversions of surface water from the Reclamation Ditch, Tembladero Slough, and Blanco Draft, and the diversions of agricultural wash water and stormwater to the Regional Wastewater Treatment Plant. Implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with uses similar to those analyzed in the prior CEQA documents and would not modify the diversions of surface water from the Reclamation Ditch, Tembladero Slough, and Blanco Draft, or the diversions of agricultural wash water and stormwater to the Regional Wastewater Treatment Plant. Further, implementation of the SPERSS and SSWMP Projects would enable additional diversion of stormwater to the IWTF. Currently, all diverted stormwater flows are combined with industrial wastewater, requiring large-capacity pumping at the IPS and treatment via the Aeration Basin at the IWTF. The SPERSS and SSWMP Projects would allow the stormwater to be conveyed to the IWTF separately from industrial wastewater, which would improve the capacity of flows between the TP-1 and IWTF, better match water quality to treatment methods, and achieve more sustainable and efficient operation of the IWTF. With implementation of the SPERSS and SSWMP Projects, the stormwater would also be conveyed directly to Percolation Pond 1 at the

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IWTF. With implementation of the SPERSS and SSWMP Projects, the City anticipates increasing stormwater capture to the IWTF by an average of 41 AFY and a peak of up to 652 AFY.

Therefore, local changes in recharge and water levels, as well as effects on nearby wells, which would occur with implementation of the SPERSS and SSWMP Projects would be less than significant, similar to the PWM/GWR Project.

Due to the limited amount of impervious surfaces constructed at the TP-1 and IWTF sites (less than 200 square feet [sf]), and because the surrounding area would remain unpaved, the prior CEQA documents determined that the increase in impervious surface area at these sites would not substantially interfere with groundwater recharge. As implementation of the SPERSS and SSWMP Projects would not result in the construction of significantly more impervious surface area at the TP-1 and IWTF sites than what was analyzed in the prior CEQA documents, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would not substantially interfere with groundwater recharge at these sites.

Because the PWM/GWR Project would provide additional water for downgradient groundwater extraction, the prior CEQA documents indicated that implementation of the PWM/GWR Project would result in both higher and lower water levels in existing basin wells over time, depending on the timing of extraction and the current storage in the basin. However, modeling performed for the prior CEQA documents determined that simulated water levels would be generally higher than pre-project levels. Further, it was determined that no nearby municipal or private production wells would experience a reduction in well yield and all existing wells would be capable of pumping the current level of production or up to the permitted production rights.

Therefore, the prior CEQA documents determined that impacts related to groundwater supply would be less than significant. As implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with similar uses as those analyzed in the prior CEQA documents and would not include any new uses that would require substantial groundwater supply, similar to the PWM/GWR Project, operation of the SPERSS and SSWMP Projects would result in a less than significant impact to water levels in existing basin wells.

As described in the prior CEQA documents, seepage into the Salinas River derived from existing IWTF pond percolation consistently exceeds the surface water quality objective for nitrate and occasionally degrades Salinas River water quality with respect to total dissolved solids, chloride, and phosphorus. Because the PWM/GWR Project would decrease the annual volume of water percolated at the IWTF, the prior CEQA documents determined that implementation of the PWM/GWR Project would decrease the input of those contaminants to the river, resulting in a beneficial impact. As implementation of the SPERSS and SSWMP Projects would develop the TP- 1 and IWTF sites with similar uses as those analyzed in the prior CEQA documents, would not substantially increase percolation of contaminated waters, and would be subject to similar federal, State, and local statutes and regulations established to protect water quality, similar to the PWM/GWR Project, impacts on groundwater quality would be less than significant.

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Surface Water. The prior CEQA documents indicated that construction of the PWM/GWR Project would degrade water quality as a result of erosion and siltation generated from earthmoving activities or the accidental release of hazardous construction chemicals. As construction of the PWM/GWR Project would disturb more than 1 acre of soils, the prior CEQA documents indicated that all construction activities would be subject to the currently adopted NPDES Construction General Permit, including preparation of a SWPPP, and the Municipal Stormwater Permit requirements. In addition, because earthwork activities within waters of the State (i.e., trenching and excavation) is considered a discharge and is regulated by the United States Army Corps of Engineers (USACOE), the PWM/GWR Project would also require a Clean Water Act Section 404 Permit from the USACOE and a Section 401 Water Quality Certification from the Regional Water Quality Control Board (RWQCB). With compliance with the NPDES Construction General Permit (including the implementation of a SWPPP), Clean Water Act Sections 404 and 401, and other waste discharge requirements as necessary, the prior CEQA documents determined that the PWM/GWR Project would have a less than significant impact on water quality during construction. As implementation of the SPERSS and SSWMP Projects would be located on the same sites as those analyzed in the prior CEQA documents and construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents, construction of the SPERSS and SSWMP Projects would be required to comply with the most current NPDES Construction General Permit (General Permit for Stormwater Discharges Associated with Construction and Land Disturbance Activities [Order No. 2022-0057-DWQ, NPDES No. CAS000002]), Clean Water Act Sections 404 and 401, and other applicable waste discharge requirements. By complying with applicable permits and requirements, construction of the SPERSS and SSWMP Projects would result in a less than significant impact on water quality during construction.

The prior CEQA documents also indicated that due to varying subsurface water levels and depths of excavation throughout the PWM/GWR Project area, evacuation during construction of project components may encounter shallow or perched groundwater, requiring temporary construction dewatering. Specifically, the TP-1 and IWTF sites are located in an area underlain by Holocene alluvial deposits, with groundwater at approximately 10 feet below ground surface.

As a result, the prior CEQA documents determined that trench excavations at these sites may encounter groundwater, moist to wet soils, and soft ground conditions, and trench dewatering may be required. However, most of the dewatering effluent generated during construction and excavation would be considered low-threat and can be discharged to land or local receiving water provided that the effluent complies with the currently adopted General Wate Discharge Permit relating to construction dewatering activities. As such, the prior CEQA documents determined that with adherence to permit requirements, construction dewatering associated with the PWM/GWR Project would not have a significant impact on water quality. As implementation of the SPERSS and SSWMP Projects would be located on the same sites as analyzed in the prior CEQA documents and construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents, construction of the SPERSS Project may also require trench dewatering. Similar to the PWM/GWR Project, construction dewatering would be required to comply with the most current dewatering permit (Waste Discharge Requirements NPDES General Permit for Discharges with Limited Threat to Water Quality [Order No. R3-2022-0335, NPDES No.

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CAG99304]). Therefore, with adherence to current permit requirements, similar to the PWM/GWR Project, construction of the SPERSS and SSWMP Projects would not have a significant impact on water quality due to construction dewatering.

The prior CEQA documents determined that the diversion of agricultural wash water and City stormwater associated with improvements at the TP-1 and IWTF sites would allow for water to be conveyed to the Regional Wastewater Treatment Plant to be treated and recycled.

Implementation of the SPERSS and SSWMP Projects would provide increased beneficial impacts due to the inclusion of the SRSW trash capture device and construction of the Segregated Stormwater Diversion Facility at the TP-1 site. The trash capture device and a diversion facility, including conveyance piping, metering, and associated infrastructure, would be installed at TP-1 to improve the capacity and quality of stormwater transported to the IWTF. The SRSW trash capture device would treat stormwater flows from the SRSW and support compliance with the City of Salinas MS4 NPDES Permit (Order No. R3-2019-0073, NPDES No. CA0049981) by improving the water quality of flows discharged to the Salinas River and the IWTF.

Implementation of the SPERSS Project would allow stormwater to be conveyed to the IWTF separately from industrial wastewater in order to improve the capacity of flows between the TP- 1 and IWTF, better match water quality to treatment methods, and achieve more sustainable and efficient operation of the IWTF. With implementation of the SPERSS and SSWMP Projects, the stormwater would also be conveyed directly to Percolation Pond 1 at the IWTF, resulting in energy savings and improved operational capacity and flexibility. Additionally, the SPERSS and SSWMP Projects would include implementation of a wetland rehabilitation pilot study to determine the most cost-effective phosphate removal process. Therefore, implementation of the SPERSS and SSWMP Projects would result in additional beneficial effects to water quality compared to the PWM/GWR Project due to the additional diversion and treatment of polluted waters and the inclusion of the wetland rehabilitation pilot study.

The prior CEQA documents indicated that implementation of the PWM/GWR Project components at the TP-1 and IWTF sites would increase the amount of impervious surface area at the sites, thereby altering drainage patterns and potentially increasing stormwater runoff.

However, due to the limited amount of impervious surfaces constructed at the TP-1 and IWTF sites (less than 200 sf), and because the surrounding area would remain unpaved, rainwater falling on the facilities would sheet flow to unpaved areas and be allowed to infiltrate the ground in accordance with State and local permits. In addition, the prior CEQA documents indicated that the PWM/GWR Project would be subject to the post-construction stormwater management requirements of applicable municipal stormwater permits and other requirements that require projects to implement post-construction stormwater BMPs and incorporate low impact development measures into the final site designs and construction in compliance with the applicable municipal stormwater permits. As implementation of the SPERSS and SSWMP Projects would not result in the construction of significantly more impervious surface area at the TP-1 and IWTF sites than what was analyzed in the prior CEQA documents, and because the SPERSS Project would also require BMPs and low-impact development measures in compliance with the applicable municipal stormwater permits, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would have a less than significant impact related to alteration of drainage patterns and increased runoff.

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The prior CEQA documents also indicated that portions of the PWM/GWR Project, including improvements at the TP-1 and IWTF sites, would be located within a 100-year flood hazard area and within the area of inundation in the unlikely event that either the Nacimiento or San Antonio dams fail. However, as the improvements at the TP-1 site would be below ground, the prior CEQA documents determined that construction of the improvements would not impede or redirect flood flows. The prior CEQA documents further determined that improvements at the IWTF site would be small and would not impede or redirect flood flows or necessitate revision of the flood maps. However, it should be noted that the prior CEQA documents determined that the ponds at the IWTF site themselves could be damaged by flood flows and the City may be required to rebuild or reconstruct all or part of the Salinas Treatment Facility in the event of a 100-year flood. In addition, the prior CEQA documents determined that project components at the TP-1 and IWTF sites are not considered at risk of loss due to inundation from dam failure because they include structures and infrastructure that would not be damaged by temporary inundation and because they would not expose people or structures to risk from flooding due to sea level rise and storm surges or tides, as they are located outside of coastal erosion hazard zones.

Implementation of the SPERSS and SSWMP Projects would be located on the same sites as those analyzed in the prior CEQA documents and would be subject to the same flood hazard conditions. Improvements at the TP-1 site under the SPERSS and SSWMP Projects would not include additional aboveground structures that could impede or redirect flows. The SPERSS and SSWMP Projects includes upgrades to select IWTF electrical components associated with the IPS, which would enhance its flood and climate resilience. All of these existing components, including motor controls, a transformer, and related instrumentation, would be replaced with new state-of-the-art equipment at a secure location above the 100-year floodplain. Therefore, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would have a less than significant impact associated with the impediment or redirection of flood flows.

In addition, because the SPERSS and SSWMP Projects would be located at the same sites as those analyzed in the prior CEQA documents and would develop the sites with similar infrastructure and uses, implementation of the SPERSS and SSWMP Projects would result in similar impacts associated with inundation from dam failure and risk of flooding due to sea level rise and storm surges or tides as the PWM/GWR Project. Similar to the PWM/GWR Project, impacts would be less than significant.

The prior CEQA documents also determined that operation of the PWM/GWR Project would not expose people or structures to substantial risk from flooding due to seiche, tsunami, or mudflow as the PWM/GWR Project would not construct habitable structures near isolated bodies of water subject to inundation by seiche, no mudflows have been mapped at the sites, and the predominantly underground facilities would be located outside of the geographic area likely to be damaged by a tsunami. Because implementation of the SPERSS and SSWMP Projects would occur on the same sites as those analyzed in the prior CEQA documents, similar to the PWM/GWR Project, the SPERSS and SSWMP Projects components would not expose people or structures to substantial risk from flooding due to seiche, tsunami, or mudflow, and impacts would be less than significant.

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Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on hydrology and water quality nor result in new significant impacts.

While the prior CEQA documents prescribed Mitigation Measure HS-4 to minimize erosion and failure of exposed or unvegetated banks, this mitigation measure was not prescribed for project components at the TP-1 and IWTF sites. Therefore, mitigation measures prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Hydrology and Water Quality:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No existing mitigation measures would apply, and no new mitigation measures would be required.

5.11 LAND USE
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with land use, as discussed in more detail in the comparative analysis below, and no mitigation would be required.

Analysis of the SPERSS and SSWMP Projects. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, the SPERSS Project would be subject to the same land use plans discussed in the prior CEQA documents.

Both the TP-1 and IWTF sites are located within existing public road rights-of-way and public facility sites.

The prior CEQA documents determined that the PWM/GWR Project components would conflict with applicable land use plans, policies, and regulations. As such, the prior CEQA documents prescribed mitigation to reduce potential impacts on the environment, which would ensure the PWM/GWR Project would be consistent with relevant plans. Mitigation measures relating to air quality, biological resources, cultural resources, energy, geology and soils, noise and vibration, public services and utilities, and traffic and transportation were prescribed throughout the prior CEQA documents in order to reduce potential impacts resulting from implementation of the PWM/GWR Project. With implementation of these mitigation measures, the prior CEQA documents determined that the PWM/GWR Project would be consistent with applicable land use plans, policies, and regulations. The SPERSS and SSWMP Projects would be subject to the applicable mitigation measures detailed in the prior CEQA documents and discussed throughout this Addendum in the

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analyses for each issue area. With implementation of the applicable mitigation measures, similar to the PWM/GWR Project, the SPERSS Project would be consistent with applicable plans, policies, and regulations.

The TP-1 site is predominantly surrounded by land within unincorporated Monterey County that is currently used for agricultural production. The prior CEQA documents identified that the TP-1 site is designated as Other Land by the California Department of Conservation. As such, implementation of the PWM/GWR Project at the TP-1 site would not result in any conversion of farmland to nonagricultural use. Since a portion of the SPERSS and SSWMP Projects would be located on the same TP-1 site analyzed in the prior CEQA documents, implementation of the SPERSS and SSWMP Projects would not result in a conversion of farmland to nonagricultural use. Therefore, similar to the PWM/GWR Project, impacts associated with agriculture and forestry resources would be less than significant.

The IWTF site is surrounded by agricultural operations to the north, east, and west, and the Salinas River to the south. The prior CEQA documents identified the IWTF site as designated by the California Department of Conservation as both Prime Farmland and Urban and Build-Up Land. The PWM/GWR Project included the slip-lining of an existing 33-inch industrial wastewater pipeline within land designated as Prime Farmland. To minimize temporary construction-related disturbance impacts to agricultural uses in areas designated as Prime Farmland, the prior CEQA documents prescribed Mitigation Measure LU-1 (Minimize Disturbance to Farmland), which requires that construction contractors minimize ground disturbance on lands designated as important farmland and restore the impacted farmland to pre-construction conditions.

The SPERSS and SSWMP Projects, as currently proposed, would include rehabilitation of a 33-inch pipeline for influent stormwater flow, which, similar to the PWM/GWR Project, would require some construction work within land designated as Prime Farmland. However, this work would not result in the permanent conversion of agricultural land to a nonagricultural use and would not result in a substantial temporary disturbance of agricultural uses in areas designated as Prime Farmland beyond what was analyzed and mitigated in the prior CEQA documents. Therefore, similar to the PWM/GWR Project, with implementation of Mitigation Measure LU-1, the SPERSS and SSWMP Projects would have a less than significant impact associated with the conversion of farmland to nonagricultural use during construction activities.

The prior CEQA documents also determined that no lands in the PWM/GWR project area, which included the TP-1 and IWTF sites, were enrolled in the Williamson Act program. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, similar to the PWM/GWR Project, the SPERSS and SSWMP Projects would have no impacts associated with conflict with lands under a Williamson Act contract.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts on land use and planning or agriculture and forestry resources, nor result in new significant impacts. With implementation of Mitigation Measure LU-1 as discussed above, there would be no new or substantially more severe significant impacts related to agricultural resources.

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While the prior CEQA documents did prescribe Mitigation Measure LU-3 to reduce operational impacts on farmland, this mitigation measure was not prescribed for project components at the TP- 1 and IWTF sites. Therefore, Mitigation Measure LU-3 prescribed for the PWM/GWR Project would not apply to the SPERSS Project.

Findings Related to Land Use:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measure LU-1 would apply, and no new mitigation measures would be required.

5.12 MINERAL RESOURCES
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with mineral resources, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, the SPERSS and SSWMP Projects would be subject to the same mineral resource conditions discussed in the prior CEQA documents.

The prior CEQA documents determined that neither the TP-1 nor the IWTF site is located within a designated mineral resource zone (MRZ) and therefore do not contain any known locally important mineral resources. As the SPERSS and SSWMP Projects would be located in the same area as the PWM/GWR Project, similar to the PWM/GWR Project, the SPERSS and SSWMP Projects would not result in the loss of availability of a known mineral resource of value to the region or residents of the State, or the loss of availability of a locally important mineral resource recovery site.

Findings Related to Mineral Resources:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

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2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No mitigation measures were prescribed in the prior CEQA documents, and no new mitigation measures would be required.

5.13 NOISE
Summary Finding of the Prior CEQA Documents. The prior CEQA documents analyzed impacts on noise and vibration with implementation of the PWM/GWR Project. Although the prior CEQA documents identified two significant and unavoidable impacts associated with construction noise, these impacts only occurred at the Tembladero Slough and during construction of the Monterey Pipeline Alternative. Neither of these significant and unavoidable impacts were associated with construction activities at the TP-1 or IWTF sites. The prior CEQA documents concluded that the PWM/GWR Project components at the TP-1 and IWTF sites would have less than significant impacts associated with noise and vibration, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents determined that the maximum noise levels at the nearest residences generated by construction activities at both the TP- 1 and IWTF sites would not exceed the significance thresholds for speech interference during the day or sleep disturbance at night. In addition, construction noise levels (approximately 45 A- weighted decibels [dBA] equivalent continuous noise level [Leq]) from construction at the TP-1 site at the nearest residences would be below the City’s noise standards. The prior CEQA documents also determined that construction-related vibration at the TP-1 and IWTF sites would not exceed Caltrans’ recommendation for vibration limits to prevent the damage of nearby structures.

Therefore, the prior CEQA documents determined that construction of the PWM/GWR Project would result in less than significant noise and vibration impacts and would not exceed or violate applicable standards. As the SPERSS and SSWMP Projects would be located at the same sites analyzed in the prior CEQA documents and would require similar construction activities, including methods, equipment, and duration, similar to the PWM/GWR Project, construction of the SPERSS and SSWMP Projects would have less than significant noise and vibration impacts.

The prior CEQA documents determined that operational noise impacts at the TP-1 and IWTF sites would be less than significant. Under the SPERSS and SSWMP Projects, no new permanent noise- generating equipment is proposed at either the TP-1 or IWTF sites and operational noise levels at both sites would be similar to those analyzed in the prior CEQA documents. Therefore, similar to the PWM/GWR Project, operational noise impacts would be less than significant.

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While the prior CEQA documents did prescribed Mitigation Measures NV-1a through NV-1d, NV-2a, and NV-2b to address significant and unavoidable construction noise impacts, these mitigation measures were not prescribed for project components at the TP-1 and the IWTF sites. Therefore, mitigation measures prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

Findings Related to Noise:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No existing mitigation measures would apply, and no new mitigation measures would be required.

5.14 POPULATION AND HOUSING
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with population and housing, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. Similar to the PWM/GWR Project, the SPERSS and SSWMP Projects would not include the construction of new homes or businesses in the area. In addition, the prior CEQA documents indicated that the construction workforce requirements for the PWM/GWR Project would be met with the local labor force within the Monterey Bay area, which would not create demand for additional housing. While some workers might temporarily relocate from other areas, the increase would be minor and temporary, and would not result in a substantial permanent increase in population. Therefore, similar to the PWM/GWR Project, the SPERSS and SSWMP Projects would not result in substantial population growth in the region during construction or operation.

Findings Related to Population and Housing:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

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2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No mitigation measures were prescribed in the prior CEQA documents, and no new mitigation measures would be required.

5.15 PUBLIC SERVICES
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with public services, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents determined that any demand for public services with implementation of the PWM/GWR Project would be met through existing service providers without the need for new or physically altered governmental facilities to maintain existing service levels. Because the SPERSS and SSWMP Projects would not include housing or employment creation facilities and would not result in substantial population growth, the SPERSS and SSWMP Projects, similar to the PWM/GWR Project, would not increase demand for school services, new park facilities, or other public facilities or services within the vicinity of the project site.

The prior CEQA documents determined that construction-related solid waste disposal would not exceed the current Monterey Peninsula Landfill permitted daily solid waste acceptance rate.

Construction activities associated with the SPERSS and SSWMP Projects would be similar to those identified and analyzed in the prior CEQA documents and would result in similar amounts of construction solid waste. In addition, the proposed improvements at the TP-1 and IWTF sites would not generate operational solid waste that would exceed the Monterey Peninsula Landfill permitted daily tonnage. Therefore, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP projects would not exceed landfill capacity during construction or operation.

Similar to the PWM/GWR Project, construction waste materials generated by the SPERSS and SSWMP Projects could make it difficult for the local jurisdictions to achieve solid waste diversion goals and other local regulations. Therefore, Mitigation Measure PS-3, requiring preparation and implementation of a construction waste reduction and recycling plan, would remain applicable to the SPERSS and SSWMP Projects.

The prior CEQA documents determined that the amount of construction water used at any individual construction sites would be negligible (estimated to be a one-time use of approximately 70 acre-feet total, or about 1.1 acre-foot per acre of ground disturbance) in comparison to total water demand of tens of thousands of acre-feet every year within the surrounding area. Further, no new or expanded water supplies, entitlements, or facilities would be needed to meet construction- related water demands. The prior CEQA documents also determined that implementation of the

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PWM/GWR Project would result in minimal increased water demand due to the employment of nine new permanent workers, which could be served by existing water suppliers.

The prior CEQA documents indicated that the PWM/GWR Project operations would require substantial new sources of water supplies to meet its project objectives of recycling wastewater for beneficial use. Technical reports supporting the prior CEQA documents and impacts analysis and other facts in the record demonstrate that it is reasonably likely that approximately 16,000 to 17,000 AFY of surplus waters can feasibly be made available to meet PWM/GWR Project demands of approximately 9,860 AFY. As such, the prior CEQA documents concluded that impacts would be less than significant. The improvements to the TP-1 and IWTF sites proposed by the SPERSS and SSWMP Projects would not generate a significant water demand. Therefore, implementation of the SPERSS and SSWMP Projects would not generate significant water demand during construction or operation, and impacts would be less than significant.

According to the prior CEQA documents, construction at all sites would result in minimal wastewater generation from construction workers, and the existing Regional Wastewater Treatment Plant has more than sufficient capacity to serve temporary construction-related increases in wastewater requiring treatment. In addition, the prior CEQA documents determined that the PWM/GWR Project would result in a minimal increase in wastewater treatment demand due to the employment of nine new permanent workers, which could be treated by existing infrastructure. The improvements to the TP-1 and IWTF sites proposed by the SPERSS and SSWMP Projects would not generate additional wastewater demand beyond what was identified in the prior CEQA documents. Therefore, similar to the PWM/GWR Project, implementation of the SPERSS and SSWMP Projects would not generate significant wastewater demand during construction or operation.

The prior CEQA documents determined that any demand for recreational facilities with implementation of the PWM/GWR Project would be met through existing facilities without the need for new or physically altered facilities to maintain existing service levels. Because the SPERSS and SSWMP Projects would not include housing or employment creation facilities and would not result in substantial population growth, the SPERSS and SSWMP Projects, similar to the PWM/GWR Project, would not increase demand for new park facilities within the vicinity of the project site.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts associated with public services, recreation, or utilities and service systems nor result in new significant impacts. With implementation of Mitigation Measure PS-3, as discussed above, there would be no new or substantially more severe significant impacts related to public services, recreation, or utilities and service systems.

Findings Related to Public Services:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

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3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measure PS-3 would apply, and no new mitigation measures would be required.

5.16 RECREATION
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with recreation, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. In prior CEQA documents, impacts associated with recreation were analyzed as part of the discussion of impacts to public services. As such, Section

5.15, Public Services, of this Addendum provides the comparative analysis for impacts associated with recreation.

5.17 TRANSPORTATION
Summary Finding of the Prior CEQA Documents. The prior CEQA concluded that the PWM/GWR Project would have less than significant impacts associated with transportation with incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents determined that construction of PWM/GWR Project components at the TP-1 site would generate approximately 34 daily construction worker trips distributed across two routes, with approximately 7 peak-hour trips along any one route. Construction of PWM/GWR Project components at the IWTF site would generate approximately 48 daily construction trips distributed across two routes, with approximately 13 peak-hour trips along any one route. Due to the low volumes along these routes and the short duration of the construction period, the prior CEQA documents determined that traffic impacts during construction of components at both the TP-1 and IWTF sites would be less than significant. In addition, the prior CEQA documents determined that construction at the TP-1 and IWTF sites would have no impact on parking in the area as the construction of these facility improvements would be set back from roadways, bike and pedestrian pathways, and public access to parking. Implementation of the SPERSS Project would develop the TP-1 and IWTF sites with similar uses at a similar intensity as that analyzed in the prior CEQA documents. Therefore, construction of the SPERSS and SSWMP Projects at these sites would be similar to the PWM/GWR Project, requiring similar numbers of construction worker vehicle trips and parking spaces.

Therefore, similar to the PWM/GWR Project, temporary traffic and parking impacts associated with construction of the SPERSS and SSWMP Projects would be less than significant.

The prior CEQA documents determined that construction activities at the TP-1 and IWTF sites would not result in any traffic delays, safety hazards, or disruption of access as the construction of project improvements at these sites would not be within roadways. Construction activities at the TP-1 and IWTF sites would also not impede vehicular, bicycle, or pedestrian traffic flow or disrupt public transportation. However, the use of trucks to transport construction equipment and materials to and from construction sites could affect road conditions on local roadways that may not have been constructed to support use by heavy construction trucks and vehicles. Therefore, construction truck

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trips could cause excessive wear on these roadways. In order to address this potential impact, the prior CEQA documents prescribed Mitigation Measure TR-3, which requires rehabilitation of any roadways damaged following construction. As the SPERSS and SSWMP Projects would be located at the same TP-1 and IWTF sites analyzed in the prior CEQA documents, implementation of the SPERSS and SSWMP Projects would not result in any traffic delays, safety hazards, or disruption of access, similar to the proposed project. In addition, although implementation of the SPERSS and SSWMP Projects would require the construction of a siphon at the Hitchcock Road crossing, potential impacts associated with activities at the Hitchcock Road crossing were included in the prior CEQA documents. The prior CEQA documents did not identify any significant impacts associated with construction or operation at this location. Therefore, construction activities at this location are not anticipated to result in any traffic delays, safety hazards, or disruption of access, similar to the PWM/GWR Project. [To be confirmed pending information from Vinod.] Also, similar to the PWM/GWR Project, Mitigation Measure TR-3 would apply to the SPERSS and SSWMP Projects to reduce potential impacts related to the degradation of local roadways to less than significant levels.

The prior CEQA documents determined that PWM/GWR Project components at the TP-1 and IWTF sites would not require new employees for operation or maintenance of the facilities, result in the ongoing delivery of materials, or generate solid waste that would need to be hauled off site.

Therefore, the prior CEQA documents determined that no impact related to operational traffic would occur with implementation of PWM/GWR Project components at the TP-1 and IWTF sites.

As implementation of the SPERSS and SSWMP Projects would develop the TP-1 and IWTF sites with similar uses as the PWM/GWR Project, operation of the proposed improvements would result in similar traffic impacts on the surrounding circulation system. However, implementation of the SPERSS and SSWMP Projects would include the installation of a trash capture device at the TP-1 site, which would require vacuum trucks to periodically pump out trash, sediment, oil/grease, and water that has collected at the bottom as part of ongoing operation/maintenance activities. Although this would result in a small increase in vehicle trips to and from the TP-1 site not previously identified and analyzed in the prior CEQA documents, this small increase in traffic would be minimal relative to existing conditions and would not substantially increase daily traffic volumes on local or regional roadways as the removal of trash, sediment, oil/grease, and water from the bottom of the trash capture device would occur only several times per year during the rainy season. Similar to the PWM/GWR Project, no new employees would be required at either the TP-1 or IWTF sites and no additional daily vehicle trips to and from the IWTF site would occur with implementation of the SPERSS and SSWMP Projects. Therefore, similar to the PWM/GWR Project, impacts related to operational traffic associated with the SPERSS and SSWMP Projects would be less than significant.

While the prior CEQA documents did prescribe Mitigation Measure TR-2 to reduce impacts from roadway construction and detours, this mitigation measure was not prescribed for project components at the TP-1 and IWTF sites. Therefore, mitigation measures prescribed for the PWM/GWR Project would not apply to the SPERSS and SSWMP Projects.

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Findings Related to Transportation:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measure TRA-3 would apply, and no new mitigation measures would be required.

5.18 TRIBAL CULTURAL RESOURCES
Summary Finding of the Prior CEQA Documents. Although the prior CEQA documents did not specifically address tribal cultural resources, the prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with cultural resources and included mitigation to address potential impacts on tribal cultural resources with implementation of the PWM/GWR Project.

Analysis of the SPERSS and SSWMP Projects. As previously discussed, no recorded or known archaeological resources or human remains were identified on either the TP-1 or IWTF sites.

However, the prior CEQA documents prescribed Mitigation Measure CR-2b, detailing measures to address the inadvertent discovery of archaeological resources or human remains, and Mitigation Measure CR-2c, requiring that all listed Native American contacts be notified of any and all discoveries. These mitigation measures would also be applicable to the discovery of unknown tribal cultural resources and/or Native American remains. As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, implementation of the SPERSS and SSWMP Projects would result in similar impacts on tribal cultural resources as the PWM/GWR Project. Mitigation Measures CR-2b and CR-2c would remain applicable to the SPERSS and SSWMP Projects to reduce potential impacts on the inadvertent discovery of tribal cultural resources or Native American remains to less than significant levels.

Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would not substantially increase the severity of the previously identified impacts on tribal cultural resources, nor would it result in new significant impacts. With implementation of Mitigation Measures CR-2b and CR-2c as discussed above, there would be no new or substantially more severe significant impacts related to cultural resources.

Findings Related to Tribal Cultural Resources:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

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3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. Mitigation Measures CR-2b and CR-2c would apply and no new mitigation measures would be required.

5.19 UTILITIES AND SERVICE SYSTEMS
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with utilities and service systems with incorporation of mitigation, as discussed in more detail in the comparative analysis below.

Analysis of the SPERSS and SSWMP Projects. In prior CEQA documents, impacts to utilities and service systems were analyzed as part of the discussion of impacts to public services. As such, Section 5.15, Public Services, of this Addendum provides the comparative analysis for impacts associated with utilities and service systems.

5.20 WILDFIRE
Summary Finding of the Prior CEQA Documents. The prior CEQA documents concluded that the PWM/GWR Project would have less than significant impacts associated with wildfire, as discussed in more detail in the comparative analysis below, and no mitigation measures were required.

Analysis of the SPERSS and SSWMP Projects. The prior CEQA documents indicated that the TP-1 and IWTF sites are located within a Local Responsibility Area (LRA) and are not located within any Fire Hazard Zone. However, an area of Very High Fire Hazard Severity Zone (VHFHSZ) within an LRA is located approximately 0.9 mile southwest of the IWTF site. The prior CEQA documents determined that because construction of the PWM/GWR Project would be required to comply with the Public Resources Code and any additional requirements imposed by the California Department of Forestry and Fire Protection (CAL FIRE) and local fire protection departments, potential impacts related to wildland fires due to construction activities would be less than significant.

As the SPERSS and SSWMP Projects would be implemented at the TP-1 and IWTF sites, which were analyzed in the prior CEQA documents, and because construction activities associated with the SPERSS and SSWMP Projects would also be required to comply with the Public Resources Code and any additional requirements imposed by CAL FIRE and the local fire protection departments, similar to the PWM/GWR Project, potential impacts related to wildland fires due to construction activities would be less than significant.

Although the prior CEQA documents did not address potential operational impacts related to wildfire, improvements proposed as part of the SPERSS and SSWMP Projects would be consistent with and similar in nature to existing facilities at the TP-1 and IWTF sites and would not include any design features that would increase the potential for wildlife, affect emergency access/response, require the installation or maintenance of associated infrastructure that may exacerbate fire risk, or expose people or structures to significant risks as a result of post-fire slope instability or drainage and runoff. Therefore, impacts related to wildlife would be less than significant.

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Based on the information in the prior CEQA documents and this environmental analysis, the SPERSS and SSWMP Projects would neither substantially increase the severity of the previously identified impacts associated with wildfire nor result in new significant impacts.

Findings Related to Wildfire:

1. No new significant effects or substantial increase in the severity of previously identified significant effects requiring major changes to the prior CEQA documents;

2. No substantial change in project circumstances requiring major revisions to the prior CEQA documents;

3. No new information not known at the time the prior CEQA documents were approved showing new or more severe significant effects; and

4. No mitigation measures were prescribed in the prior CEQA documents and no new mitigation measures would be required.

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6.0 DETERMINATION
Based on the information and analyses in this Addendum to the prior CEQA documents for the PWM/GWR Project and pursuant to Section 15162 of the State CEQA Guidelines, the City of Salinas has determined the following.

6.1 SUBSTANTIAL CHANGES TO THE PROJECT
There are no substantial changes associated with the SPERSS Project that would require major revisions of the prior CEQA documents due to new significant environmental effects or a substantial increase in the severity of impacts identified in the prior CEQA documents. Additionally, the changes identified with the SPERSS Project do not substantially change the scope of proposed improvements proposed and evaluated in the prior CEQA documents.

6.2 SUBSTANTIAL CHANGES IN CIRCUMSTANCES
The existing environmental conditions or circumstances under which the SPERSS Project is being undertaken have not changed, and implementation of the proposed minor modifications to the PWM/GWR Project would not result in new significant environmental effects or a substantial increase in the severity of significant environmental effects compared to those disclosed in the prior CEQA documents.

6.3 NEW INFORMATION
No new information of substantial importance, which was not known and could not have been known when the prior CEQA documents were approved, has been identified to show that the proposed minor modifications to the PWM/GWR Project would be expected to result in:

1. One or more new significant effects not discussed in the prior CEQA documents;

2. Impacts determined to be significant in the SPERSS and SSWMP Projects that would be substantially more severe;

3. Additional mitigation measures or alternatives to the SPERSS and SSWMP Projects that would substantially reduce one or more significant effects identified in the prior CEQA document; or

4. Additional mitigation measures or alternatives previously determined to be infeasible that would in fact be feasible and would substantially reduce one or more significant effects of the SPERSS and SSWMP Projects, but the City declines to adopt the mitigation measure or alternative.

In addition, the proposed minor modifications associated with the SPERSS and SSWMP Projects would not require new mitigation measures because no new or substantially more severe impacts are expected beyond those identified in the prior CEQA documents.

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7.0 CONCLUSION
On the basis of the evaluation presented above, the SPERSS and SSWMP Projects, if implemented, would not result in any of the conditions listed under Section 5.0, CEQA Framework for Use of an Addendum, of this memorandum, requiring preparation of a subsequent or supplemental EIR. Thus, this Addendum satisfies the requirements of State CEQA Guidelines Sections 15162 and 15164.

Therefore, no further environmental review is required beyond this Addendum to the prior CEQA documents.

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APPENDIX A

MITIGATION MONITORING AND REPORTING PROGRAM

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Salinas City CouncilMay 6, 2025

Salinas City Council
May 6, 2025