EPA Selects Final Cleanup Plan for the Sulphur Bank Mercury Mine Superfund Site
SAN FRANCISCO – The U.S. Environmental Protection Agency (EPA) today announced the final cleanup plan for the Sulphur Bank Mercury Mine Superfund site, covering the mine site and residential soils in Clearlake Oaks, Calif. EPA’s cleanup plan will combine and cover mine waste piles, remove or cover contaminated residential soils, minimize impacts on nearby tribes, and reduce mercury entering Clear Lake sediments and fish. The mine operated from the late 1800s to the 1950s, spreading waste with toxic levels of mercury and arsenic across the mine property and into nearby neighborhoods and Clear Lake.
“This cleanup plan marks the culmination of years of planning with tribes, local government and the state to develop a joint vision for reviving the local environment and economy around Clear Lake,” said EPA Pacific Southwest Regional Administrator Martha Guzman. “EPA is committed to continuing our coordination with local stakeholders, ensuring community-wide benefits, returning land to the Elem Indian colony and collaborating on the protection of tribal and cultural resources.”
“We’re thrilled to see this project move into the next phase,” California Department of Toxic Substances Control Director, Dr. Meredith Williams said. “A cleanup project of this magnitude takes immense coordination and expertise, and we look forward to our continued partnership with the US EPA and the Elem Indian Colony to protect the community.”
Before finalizing the cleanup plan, EPA held a 90-day public comment period and hosted online question and answer sessions, in-person open houses, and hybrid (online and in-person) formal public hearings for both the whole community and a tribal-focused audience. The agency captured both written and verbal comments, considered them in cleanup planning, and responded to them in the final decision document.
The plan is detailed in a document called a Record of Decision (ROD). The ROD and other documents on how the EPA decided on this plan are found in the site’s Administrative Record posted on EPA’s website.
EPA has already completed eight earlier cleanups at Sulphur Bank to protect community members and the environment. These prior cleanups included controlling soil erosion, improving surface water management, removing contaminated soil on the Elem Indian Colony, and capping mine waste beneath roadways. EPA also continues to study Clear Lake’s complex ecosystem, sediment, and north wetlands to understand how to reduce mercury pollution.
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