Corrective Measures Study/Feasibility Study

A Corrective Measures Study/Feasibility Study (CMS/FS) Report for contamination in groundwater was prepared by Pacific Gas and Electric Company (PG&E) to address groundwater contamination associated with past releases from the Topock Compressor Station (Station) to the Bat Cave Wash (designated as Solid Waste Management Unit [SWMU] 1/Area of Concern [AOC] 1), previous injection well PGE 8 (designated as SWMU 2), and the East Ravine (designated as AOC 10). The report was prepared to comply with both Resource Conservation and Recovery Act (RCRA)A 1976 amendment to the first federal solid waste legislation, the Solid Waste Disposal Act of 1965. In RCRA, Congress established initial directives and guidelines for U.S. EPA to regulate and manage solid waste, including hazardous waste. RCRA established a regulatory system to track hazardous substances from the time of generation to final disposal. The law requires safe and secure procedures to be used in treating, transporting, storing and disposing of hazardous wastes. RCRA was designed to prevent new, uncontrolled hazardous waste sites. and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)Commonly known as Superfund, this law created a tax on the chemical and petroleum industries and provided broad federal authority to respond directly to releases or threatened releases of hazardous substances that may endanger public health or the environment. CERCLA established prohibitions and requirements concerning closed and abandoned hazardous waste sites; provided for liability of persons responsible for releases of hazardous waste at these sites; and established a trust fund to provide for cleanup when no responsible party could be identified. The law authorizes two kinds of response actions: Short-term removals, where actions may be taken to address releases or threatened releases requiring prompt response. Long-term remedial response actions, that permanently and significantly reduce the dangers associated with releases or threats of releases of hazardous substances that are serious, but not immediately life threatening.. The report identified and evaluated cleanup options (or remedial alternatives) for the contamination and recommended a cleanup approach. A Final CMS/FS Report was submitted to California Department of Toxic Substances Control’s (DTSC)The department within the California Environmental Protection Agency in charge of the regulation of hazardous waste from generation to final disposal. DTSC oversees the investigation and cleanup of hazardous waste sites. and the U.S. Department of the Interior (DOI)The United States department charged with conservation and development of natural resources. The U.S. Department of the Interior uses sound science to manage and sustain America’s lands, water, wildlife, and energy resources, honors our nation’s responsibilities to tribal nations, and advocates for America’s island communities. on December 15, 2009. The nine remedial alternatives outlined in the CMS/FS were evaluated based on the following criteria:
  • Protection of human health and the environment
  • Compliance with Applicable, Relevant, and Appropriate Requirements (ARARs)Federal or state laws, regulations, standards, criteria or requirements which would apply to the cleanup of hazardous substances at a particular site.
  • Long-term effectiveness
  • Short-term effectiveness
  • Reduction of toxicity, mobility, and volume
  • Ability to implement
  • Cost effectiveness
  • Community acceptance
  • State and other governmental bodies' acceptance, including Tribal Nations

The Final CMS/FS Report for groundwater remedy was approved by the agencies (DTSC and DOI) in December 2009. Future cleanup actions at the Site, including soil if necessary, will be addressed in subsequent documents, as appropriate.