Welcome to the California Public Utilities Commission (CPUC) website for the California Environmental Quality Act (CEQA) review of the proposed Pacific Gas and Electric Company (PG&E) Plainfield Substation Upgrade Project (Project). PG&E filed an application for a permit to construct (PTC) for the Project on June 18, 2024 (Application A.24-06-008). This site provides access to public documents and information relevant to the CEQA review process.
Introduction and Background
PG&E, in its CPUC application (A.24-06-008) filed on June 18, 2024, requests a PTC for the Plainfield Substation Upgrade Project. The Project is subject to CEQA review because the CPUC has been presented with a discretionary action to approve or deny PG&E’s PTC application. Before making a decision about PG&E’s application, the CPUC is required to evaluate potential environmental impacts associated with the Project and present the findings in an environmental document for public review and comment, pursuant to CEQA.
The Plainfield Substation Upgrade Project would be located in unincorporated Yolo County, between the cities of Woodland and Davis, approximately 1.5 miles west of California State Route 113. The existing Plainfield Substation currently occupies approximately 0.9 acres (200 by 200 feet) adjacent to County Road 27. The Project would include the expansion and upgrade of Plainfield Substation by adding two 5 megavolt ampere reactive power (MVAR) shunt capacitor banks and related equipment that would boost the voltage of the 60 kilovolt (kV) lines to acceptable levels. The substation expansion area, located directly east and south of the existing substation boundary, is currently used for agricultural purposes. This expansion would extend the substation 415 feet east and 235 feet south of the existing substation structures, adding approximately 5.2 acres to the substation footprint. The substation expansion components would include upgrades to the existing 60 kV bus, two new shunt capacitor banks, modifications to the existing Spill Prevention Control and Counter Measures containment system, installation of a stormwater retention pond, installation of a new, larger Modular Protection Automation and Control enclosure, and the replacement and installation of tubular steel poles and all-aluminum conductor power lines. New fencing, lighting, and access road improvements would also be installed.
The application includes the Proponent’s Environmental Assessment (PEA) prepared pursuant to Rule 2.4 of the CPUC's Rules of Practice and Procedure. The Project was identified by the California Independent System Operator (CAISO) in its transmission planning process as part of the Vaca Dixon Area Reinforcement Project to ensure the reliability of the CAISO-controlled grid.
As identified by PG&E, the Project would:
- Increase service reliability to customers, including to agricultural operations, in unincorporated Yolo County and the cities of Woodland and Davis, by correcting low-voltage issues and alleviating overload conditions due to growing load in the existing system;
- Meet performance requirements established by the North American Electric Reliability Corporation (NERC) that the electric system will operate reliably during normal system conditions; and
- Design and building the CAISO-approved project in a safe and cost-effective manner while minimizing environmental impacts.
Environmental Review
As the CEQA Lead Agency, the CPUC will prepare an Initial Study (IS) to evaluate the environmental effects of the Project. If the IS determines that any potentially significant impacts can be mitigated to less-than-significant levels, then a Mitigated Negative Declaration (MND) will be prepared. The following table includes milestones and anticipated dates for the CEQA review process.
| Project Milestones as of December 2024 | |
|---|---|
| Milestone | Date |
| Application and PEA submitted by PG&E to CPUC | June 18, 2024 |
| Application Deemed Complete by CPUC | July 17, 2024 |
| Publication of Draft IS/MND
|
Second Quarter of 2025 |
| Public CEQA Review Period (30 days) | Second Quarter of 2025 | Publication of Final IS/MND | Third Quarter of 2025 | CPUC Adoption of Final IS/MND and Approval of the Project | Fourth Quarter of 2025 | Start of Construction (anticipated) | First Quarter of 2026 |
Documents Available for Review
Public documents related to the Plainfield Substation Upgrade Project, including the PTC application and PEA, can be found at the following links:
PG&E PTC Application (June 18, 2024)
Proponent's Environmental Assessment (PEA) (June 18, 2024)
PEA Appendix A: PEA Checklist
PEA Appendix B: Emissions Calculations
PEA Appendix C: Biological Resources Technical Report
PEA Appendix D: Nesting Birds: Species-Specific Buffers for PG&E Activities
PEA Appendix E: Cultural Resources Technical Report
PEA Appendix F: Historical Resources Analysis Report
PEA Appendix G Fuel Usage
PEA Appendix H: Geotechnical Report
PEA Appendix I: EDR Report
CPUC PEA Completeness Letter (July 17, 2024)
CPUC Requested Information
CPUC Completeness Letter and Data Request 1 (July 17, 2024)
PG&E Response to Data Request 1 (August 2, 2024)
CPUC Completeness Letter and Data Request 2 (December 4, 2024)
PG&E Response to Data Request 2 (December 12, 2024)
Additional Information
The CPUC Energy Division is managing the environmental review of the Project. To request additional information or to be added to the mailing list, please contact us:
Project email:
Plainfield@esassoc.com
Project voicemail: (510) 463-6731
The CPUC Project Manager is:
Tommy Alexander
California Public Utilities Commission
Energy Division - CEQA & Energy Permitting
505 Van Ness Avenue
San Francisco, California 94102
Project email: tommy.alexander@cpuc.ca.gov