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Case Summary: Cleanup Agreement Reached at Former Uranium Mine on Spokane Indian Reservation

On January 7, 2012, a settlement agreement between the U.S. Environmental Protection Agency (EPA), the Department of the Interior (DOI), Dawn Mining Company, LLC, and its corporate parent, Newmont USA Ltd. was approved by the U.S. District Court for the Eastern District of Washington. The agreement settles the mining companies’ and DOI’s liabilities under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, commonly known as Superfund) at the Midnite Mine Superfund Site.

Under the settlement, the mining companies will design, construct, and implement the cleanup plan selected by EPA in 2006 that is projected to cost approximately $193 million. The site, a former 350 acre open-pit uranium mine, poses a potential threat to people’s health and the environment because of the presence of heavy metals and elevated levels of radioactivity.

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Information about the Companies

In 1954, Jim and John LeBret, members of the Spokane Tribe, found uranium in an area of the Tribe’s Indian Reservation in Washington state. The LeBret brothers and several other tribal members formed Midnite Mines, Inc. and secured mining leases administered by the Bureau of Indian Affairs, a Bureau within DOI. Midnite Mines, Inc. then joined with Newmont USA Limited, a U.S. mining conglomerate, to create Dawn Mining Company with Newmont as the fifty-one percent shareholder and Midnite Mines, Inc. owning forty-nine percent.

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Information about the Midnite Mine Superfund Site

The Midnite Mine Superfund Site is located in eastern Washington state within the boundaries of the Spokane Indian Reservation. The site is on lands held in trust for the Spokane Tribe and individual Indian allottees.

Under leases signed by DOI and the Dawn Mining Company, the 350-acre site operated as an open-pit uranium mine between the years 1955-1965 and again from 1968-1981. As a result of the widespread mining activity, the site contains two open pits partially filled with water, four pits completely filled with waste rock, at least seven stockpiles of ore and protore, numerous dump areas, and multiple piles of waste rock. More information on the Midnite Mine Superfund Site.

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Pollutants and Environmental Effects

EPA documented cadmium, chromium, nickel, zinc, radium 226, uranium 234, uranium 238, polonium 210, copper, lead and lead 210 throughout the Site. These hazardous substances are currently present in groundwater, surface water, and sediment and pose risks to human health and the environment. In particular, local residents face the risk of contamination through residential land use, ground water ingestion, and tribal subsistence land use.

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Overview of the Settlement Agreement

The settlement agreement between the U.S. and the mining companies resolves a 2005 cost recovery action, under which the U.S. sought reimbursement for past cleanup costs incurred by EPA at the site and a declaratory judgment on liability for future costs needed to restore the site.

Cleanup Actions

Under the consent decree, the mining companies agree to perform the remedial design and remedial action (RD/RA) with EPA oversight. The RD/RA is projected to address 40 million cubic yards of contaminated soil and water. This work includes:

  • installing a drainage layer and sumps in the two pits left open after mining,
  • consolidating existing waste rock in the pits,
  • covering the pits to keep out surface water,
  • ongoing maintenance such as removal and treatment of water that enters from the pit walls.

In addition, the mining companies will reimburse EPA approximately $18.7 million for EPA’s past cleanup and oversight costs at the site and will pay 100% of EPA’s future cleanup and oversight costs.

Financial Assurance

The consent decree ensures the viability of the cleanup by requiring the mining companies to provide financial assurance in the amount of $193 million, the anticipated cost of cleanup. To fulfill this financial assurance obligation, the mining companies will deposit $42 million in a trust fund and will secure a letter of credit for $151 million.

DOI will reimburse EPA approximately $7 million for EPA’s past cleanup costs, and to settle DOI’s future liabilities at the site, DOI will provide a lump sum payment of $42 million to the mining companies. The mining companies will deposit this $42 million in a trust fund as part of its financial assurance obligation.

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For more information, contact:

David Smith-Watts
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Washington, D.C. 20460

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