Site Description and Investigation History

The Pacific Gas and Electric Company (PG&E) Topock Compressor Station (Station) compresses natural gas so it can be transported through pipelines to PG&E's customers in northern and central California. The Station is located in eastern San Bernardino County, about 12 miles southeast of the city of Needles, California, south of Interstate 40, and one-half mile west of the Colorado River. The Station is surrounded by land owned by PG&E, the Fort Mojave Indian Tribe, BNSF Railroad, and federal lands including the Havasu National Wildlife Refuge managed by the United States (U.S.) Fish and Wildlife Service, and lands owned and/or managed by the U.S. Bureau of Reclamation and the Bureau of Land Management (see the Topock Project Site (Site) location map). 

Investigation History Summary:

• Present: 
  • A revised Soil Resource Conservation and Recovery Act (RCRA) Facility Investigation/Remedial Investigation Work Plan was submitted on January 14, 2013. Pursuant to the California Environmental Quality Act, the Department of Toxic Substance Control (DTSC), a department of the California Environmental Protection Agency, is evaluating the potential environmental impacts associated with the soil investigation via a Soil Investigation Environmental Impact Report, and a draft EIR will be circulated for comment in Mid 2014. DTSC will approve or modify the Work Plan after review and respond to comments received. After receipt of DTSC and the U.S. Department of the Interior (DOI) approval of the Work Plan, PG&E will implement the field work which is anticipated to take one year. 
  • A Soil RFI/RI Volume I Addendum was submitted on March 26, 2013. Responses to comments are ongoing and a final Addendum is anticipated in 2014. 
  • On April 5, 2013, PG&E submitted the Basis of Design Report/Intermediate (60%) Design to DOI and DTSC. Responses to comments are current ongoing. The Pre-Final (90%) Design will be prepared afterwards and is currently targeted for mid-2014. 
  • PG&E and the U. S. executed a Remedial Design/Remedial Action Consent Decree under the Comprehensive Environmental Response, Compensation, and Liability Act in 2012, which was lodged with the U.S. District Court for the Central District of California in January 2013, and became effective upon approval by the court in November 2013.
  • DTSC and DOI approved the Final Implementation Plan for Alternative Freshwater Source Evaluation on September 4, 2013. Field work started on October 2, 2013 and is anticipated to continue into early 2014. 
• 2010 - 2012: 
  • Field activities were performed from December 2009 through December 2010 in compliance with the Time-Critical Removal Action (TCRA) Work Plan. During this time approximately 11,800 tons of waste material were removed from the Area of Concern (AOC) 4 Debris Ravine. On March 15, 2011, PG&E completed the Implementation Report for the TCRA at AOC 4, Pacific Gas and Electric Company Topock Compressor Station, Needles, California.
  • DOI’s Record of Decision and DTSC’s Notice of Remedy Selection were completed in December 2010 and January 2011, respectively.
  • DTSC certified the Final Environmental Impact Report for the proposed groundwater remedy decision on January 31, 2011.
  • A Draft Soil RFI/RI Work Plan was submitted in May 2011.
  • The Corrective Measures Implementation/Remedial Design Work Plan was completed in November 2011 and approved by DOI.
  • The Basis of Design/Preliminary (30%) Design of the groundwater remedy was submitted on November 18, 2011.
• 2005 - 2009: 
  • In 2005 PG&E entered into a voluntary Consent Agreement with the DOI to perform corrective actions and response actions as a result of Site contamination.
  • In compliance with the Corrective Action Consent Agreement (CACA) and the DOI Consent Agreement, data collected during environmental investigations are summarized in a three-volume Final RFI/RI Report. The RFI/RI Volume 1 - Site Background and History was completed in August 2007, and an Addendum was submitted in 2013 (see Present bullet). The RFI/RI Volume 2 - Hydrogeologic Characterization and Results of Groundwater and Surface Water Investigation was completed in February 2009. An Addendum to the RFI/RI Volume 2 Report was completed in June 2009. Both were approved by DTSC and DOI.
  • The Final Groundwater Corrective Measures Study/Feasibility Study Report for Solid Waste Management Unit (SWMU) 1/Area of Concern (AOC) 1 and AOC 10 Chromium in Groundwater was completed in 2009.
  • On June 24, 2009, DOI directed PG&E to implement a TCRA through the issuance of the AOC 4 Debris Ravine TCRA Memorandum. Work planning and consultation for the removal activities immediately ensued, and DOI approved PG&E’s Work Plan on December 15, 2009.
• 1996: PG&E entered into a voluntary agreement with the Department of Toxic Substances Control (DTSC), department of the California Environmental Protection Agency, to investigate the nature and extent and to clean up any contamination resulting from Station operations. This agreement, the Corrective Action Consent Agreement (CACA), proscribes that PG&E follows an investigation and cleanup process governed by a federal law known as the Resource Conservation and Recovery Act (RCRA).
• 1989: PG&E replaced the original single-lined evaporation ponds with double-lined ponds at a new location, and the original ponds were removed and closed. PG&E's disposal of wastewater from ongoing operations is regulated by the Colorado River Basin Regional Water Quality Control Board (Water Board), a board of the California Environmental Protection Agency (Cal/EPA).
• 1985: PG&E replaced the chromium-based additive with a phosphate-based solution.
• 1974: PG&E began disposal of all wastewater exclusively in the lined ponds.
• 1971 - 1974: PG&E alternated disposal of the treated wastewater between the injection well and the lined ponds.
• 1971: PG&E installed a series of lined evaporation ponds to receive treated wastewater.
• 1970: PG&E installed an underground injection well to receive treated wastewater.
• 1964: PG&E began treating the wastewater to remove hexavalent chromium prior to disposal.
• 1951 - 1968: Cooling tower wastewater was discharged into percolation beds in a dry wash area next to the Station (see Bat Cave Wash photo below).

• 1951 - 1985: Hexavalent Chromium was used at the Station to prevent rust in its cooling towers.
• 1951: The Station began operation.