2019-02999. Notice of Proposed Good Samaritan Settlement Agreement and Order on Consent for Removal Action for the Corona/Twin Peaks Mine Site, Napa County, California

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of proposed settlement; request for public comment.

SUMMARY:

In accordance with the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended (“CERCLA”), notice is hereby given that the Environmental Protection Agency (“EPA”), has entered into a proposed settlement, embodied in an administrative Good Samaritan Settlement Agreement and Order on Consent for Removal Action (“Settlement Agreement”), with Tuleyome. Under the Settlement Agreement, Tuleyome agrees to carry out a removal action that will include pilot studies to assess the effectiveness of various chemical amendments to address discharges from the Corona drainage tunnel, mine waste consolidation, and revegetation. The work will also include improvements to the existing infiltration trenches and construction of other surface water runoff controls.

DATES:

Comments must be received on or before March 25, 2019.

ADDRESSES:

The Settlement Agreement is available for public inspection at the United States Environmental Protection Agency, Superfund Records Center, 75 Hawthorne Street, Room 3110, San Francisco, California 94105. Telephone: [phone]. Comments should be addressed to Larry Bradfish, Assistant Regional Counsel, Office of Regional Counsel (ORC-3), U.S. Environmental Protection Agency, 75 Hawthorne Street, San Francisco, CA 94105; or Email: [e-mail]; and should reference the Corona Mine/Twin Peaks Mine Site, EPA R9-2018-17. EPA's response to any comments received will be available for public inspection at the same address.

FOR FURTHER INFORMATION CONTACT:

Larry Bradfish, Assistant Regional Counsel (ORC-3), Office of Regional Counsel, U.S. EPA Region IX, 75 Hawthorne Street, San Francisco, CA 94105; Email: [e-mail]; Phone [phone].

SUPPLEMENTARY INFORMATION:

Notice of this proposed administrative settlement is made in accordance with the Section 122(i) of CERCLA. The Settlement Agreement concerns work to be done by Tuleyome, a non-liable party in connection with the Corona Mine/Twin Peaks Mine (“Site”), located in Napa County, California. Tuleyome is a non-profit volunteer organization focused on protecting the wild and agricultural heritage of the inner Coastal Range and Western Sacramento Valley California. Tuleyome maintains offices at 607 North Street, Woodland, CA 95695. Tuleyome certifies in the Settlement Agreement that it is not a liable party under CERCLA, and that it does not intend to acquire ownership in the Site. This Settlement Agreement falls under EPA's Good Samaritan Initiative, which adopted CERCLA administrative tools including a model Administrative Settlement and Order on Consent (AOC). The purpose of these administrative tools is to reduce barriers under CERCLA for non-liable volunteers to clean up orphan mine sites. The Corona Mine/Twin Peaks Mine Settlement Agreement is based on the updated 2018 model AOC, and has been vetted with EPA Headquarters Office of Site Remediation Enforcement. Parties to the Settlement Agreement include the EPA and Tuleyome.

The Site that is the subject of this Settlement Agreement includes 32 contiguous acres of land that has been disturbed from past mining efforts at the Corona and Twin Peaks mercury mines. The 32-acre project is located within a larger 328.8-acre area that is owned by Corona/Twin Peaks Historical Association LLC which obtained the property from the previous owner, John Livermore (deceased), in 2012. Under this Settlement Agreement, Tuleyome agrees to carry out a removal action involving pilot studies to assess the effectiveness of various chemical amendments to address discharges from the Corona Mine drainage tunnel, mine waste consolidation, and revegetation. The work will also include improvements to existing infiltration trenches and construction of other surface water runoff controls. Tuleyome has performed work at the Site since 2016 under oversight by the California Regional Water Quality Control Board, Central Valley Region.

The performance of this work by Tuleyome will be overseen by EPA. The settlement includes a covenant not to sue Tuleyome pursuant to Sections 106 or 107(a) of CERCLA. EPA will consider all comments received on the Settlement Agreement in accordance with the DATES and ADDRESSES sections of this Notice and may modify or withdraw its consent to the Settlement Agreement if comments received disclose facts or considerations that indicate that the settlement is inappropriate, improper, or inadequate.

Dated: February 6, 2019.

Enrique Manzanilla,

Director, Superfund Division, EPA Region 9.