What's New

An Aquifer Test at TW-01

A tracer study and a pumping test were initiated in mid-June 2021 to obtain additional information about the subsurface in the vicinity of the Topock Compressor Station. This information will assist in refining the groundwater model that will be used to assess the performance of the groundwater remedy. DTSC conducted a California Environmental Quality Act (CEQA) review of the proposed study, and prepared/adopted an addendum to the groundwater SEIR on April 8, 2021.

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 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. In parallel, consultation with nine Tribes occurred through August 21, 2020. DOI has responded to comments received and issued responses to comments on April 23, 2021. DOI is developing a decision document, called an Action Memorandum, for the non-time-critical removal action. Once complete, the Action Memorandum, along with a Responsiveness Summary and the Final EE/CA, will be uploaded to this website as well as provided to Tribes and Stakeholders. The final EE/CA can be found here. A fact sheet on the EE/CA can be found here

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 is in Progress

The human health and ecological risk assessment (HHERA) for soil began on June 20, 2017 upon completion of the soil investigation field work. 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

Findings and conclusions of the soil investigation field work and the conclusions from the Risk Assessment are presented in the Soil Resource Conservation and Recovery Act (RCRA) Facility Investigation/Remedial Investigation (RFI/RI) Report (also called the RFI/RI Volume 3 Report). PG&E submitted a revised Soil RFI/RI Volume 3 report on May 31, 2021 for review and comment. The Soil RFI/RI Report is anticipated to be completed in early 2022. 

Clearinghouse Task Force (CTF) Meeting

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. CTF meetings generally occur every other month throughout the year.

Consultative Workgroup (CWG) Meeting

The Consultative Workgroup (CWG) is a specific group of key governmental agencies, stakeholders and Tribes established in 2000 to facilitate participation in the Site investigation and remediation process. The CWG usually meets quarterly. A CWG meeting was held on 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 June 17, 2021. 

DTSC February 2021 Fact Sheets/Community Updates

DTSC provides periodic updates on the progress of the site investigation and cleanup efforts in periodic Community Updates/ Fact Sheets. The DTSC February 2021 Fact Sheet - Community Update for the PG&E Topock Compressor Station is now available to view here.

Construction of the Final Groundwater Remedy Has Begun

Click here for the current construction activities. 

Implementation of the Final Groundwater Remedy will adhere to the Final Groundwater Design. The conditional approvals of the final design can be viewed here. The Final Groundwater Remedy Design document can be downloaded here.

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. 

PG&E resumed the construction of the groundwater remedy infrastructure starting May 11, 2020 after a 40-day temporary shutdown as a precautionary measure in response to the COVID-19 pandemic.  COVID-19 prevention measures have been implemented to maintain protection for workers and visitors.  For information about the COVID-19 pandemic, please visit the California Department of Public Health website.   

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. The TLP meets prior to critical Project decisions.

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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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