What's New

Soil Engineering Evaluation/Cost Analysis (EE/CA)

On October 30, 2018, U.S. Department of the Interior (DOI) directed PG&E to prepare a Draft Engineering Evaluation/ Cost Analysis (EE/CA). The purpose of an EE/CA is to evaluate the need for a non-time critical removal action (NTCRA) on federal lands or at locations where contamination has the potential to migrate to federal land. The public comment period for the EE/CA occurred from June 3, 2020 to August 5, 2020. DOI will respond to comments received and direct Pacific Gas and Electric (PG&E) to revise the draft EE/CA. The final EE/CA can be found here. A fact sheet on the EE/CA can be found here

Remedy Construction Resumed on May 11, 2020

PG&E resumed the construction of the groundwater remedy infrastructures starting May 11, 2020.  PG&E resumed field activities following a 40-day temporary shutdown which was implemented as a precautionary measure in response to the COVID-19 pandemic.  New COVID-19 prevention measures have been implemented to maintain protection for workers and visitors.  DTSC and the DOI will continue to coordinate with PG&E on fieldwork during the pandemic.  For updated information about the COVID-19 pandemic, please visit the California Department of Public Health website.   

Groundwater Remedy Construction Temporarily Shut Down in Response to COVID-19 Pandemic

A temporary shutdown of the groundwater remedy construction activities was initiated on April 1, 2020 to increase protection of personnel and the community in response to the COVID-19 pandemic. PG&E continued to operate and maintain the Interim Measure "pump and treat" system (also known as IM-3) to ensure the protection of the Colorado River during this period. 

For information about COVID-19, please visit the California Department of Public Health website

If you have questions or concerns regarding the project and the COVID-19 response, please contact Mr. Philip McPhaul at Philip.McPhaul@dtsc.ca.gov.

Subsequent Environmental Impact Report for Groundwater Remedy Certified

The California Department of Toxic Substances Control (DTSC) certified the Final Subsequent Environmental Impact Report (SEIR) on April 24, 2018. It can be viewed here. The Final SEIR considered and responded to comments submitted during the draft review period.

Soil Risk Assessment completed and Soil RFI/RI Reporting has begun

Upon completion of the soil investigation field work and discussion of soil data, DTSC and DOI concurred with PG&E to begin the soil human health and ecological risk assessment (HHERA) process on June 20, 2017. The HHERA assessed potential human health and ecological risks based on soil sampling data. This information will assist risk management decisions on the need for soil remediation, if any. The Soil HHERA report was submitted to agencies on October 18, 2019, and an errata was submitted on February 19, 2020. The Soil Risk Assessment Report plus errata were approved on May 29, 2020. The report can be downloaded here

Concurrently, the preparation of the Soil RFI/RI Report (also called the RFI/RI Volume 3 Report) has begun. The Soil RFI/RI Report will present the findings and conclusions of the soil investigation field work and the conclusions from the Risk Assessment. The Soil RFI/RI Report is anticipated to be completed in late 2021. 

Clearinghouse Task Force (CTF) Meeting

DTSC holds regular Clearinghouse Task Force (CTF) meetings. The CTF is a small group of representatives from State and Federal agencies, key stakeholders and Tribes formed to strategize and develop processes and tools to improve communications and enhance stakeholder understanding of Project and regulatory information. A CTF conference call was held on May 4, 2021.

Consultative Workgroup (CWG) Meeting

The Consultative Workgroup (CWG) is a specific group of key governmental agencies, stakeholders and Tribes established to facilitate participation in the Site investigation and remediation process. The CWG usually meets quarterly. A CWG meeting was held on February 17, 2021. The next CWG is planned for June 16, 2021. 

Technical Workgroup (TWG) Meeting

The Technical Workgroup (TWG) was established as a subgroup of the Consultative Workgroup (CWG) for technical experts to deliberate on various scientific aspects of the Project and remediation issues as needed. A TWG meeting was held on May 27, 2021. The next TWG is planned for June 17, 2021. 

DTSC February 2021 Fact Sheet Available

The DTSC February 2021 Fact Sheet - Community Update: Pacific Gas & Electric Company (PG&E) Topock Compressor Station, Cleanup Program Update is now available to view here.

Final Groundwater Design Approved

The U.S. Department of the Interior (DOI) conditionally approved the Final Groundwater Design and the Construction/Remedial Action Work Plan on April 3, 2018. Subsequent to certification of the Final SEIR, DTSC conditionally approved the Final Groundwater Design and the Construction/Remedial Action Work Plan on April 24, 2018. The conditional approvals can be viewed here. The Final Groundwater Remedy Design document can be downloaded here.

Construction of the Final Groundwater Remedy Has Begun

Click here for the current construction activities.

Topock Leadership Partnership (TLP) Meeting

The Topock Leadership Partnership (TLP) meeting is an opportunity for Tribal, Stakeholder, State and Federal Government, and PG&E Company leaders to interact and learn more about construction of the Topock groundwater remedy. The TLP held a meeting on September 18-19, 2018 in Lake Havasu City, Arizona.

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If you have a disability and have difficulty accessing material on this site please contact us in writing, via email or via telephone and we will work with you to make the information available. Please indicate the nature of the accessibility need, your preferred format (Braille, large print, etc.), what material you are trying to access including where it's located on this site, and how to reach you if questions arise while fulfilling your request. You can direct your requests to:


Written Requests

The Office of Civil Rights
Department of Toxic Substances Control
P.O. Box 806
Sacramento, CA 95812-0806

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+1 916 324-3095
+1 800 728-6942 - Toll Free