The Department of Justice, the U.S. Environmental Protection Agency (EPA) and the state of New Mexico today announced a settlement with Chevron Mining Inc. (CMI) requiring $143 million in cleanup work at the Chevron Questa Mine Superfund site near Questa, New Mexico. As part of the settlement, the company will perform a pilot project to cover about 275 acres of the tailing facility where mine waste or “tailings” are stored, operate a water treatment plant and install groundwater extraction systems. CMI will also pay over $5.2 million to reimburse EPA’s past costs for overseeing cleanup work at the site.

“This settlement will advance substantial cleanup work at the Questa site, and require actions to prevent future contamination of the Red River,” said Assistant Attorney General John C. Cruden for the Department of Justice’s Environment and Natural Resources Division. “This settlement is the product of excellent cooperation between the state and federal governments and CMI to continue the vital cleanup work at the Chevron Questa Mine Site.”

“This settlement builds on the consent decree entered into in September of last year and represents another affirmative step towards remedying the serious environmental damages suffered by this beautiful area of New Mexico as a result of decades of extensive mining activities,” said U.S. Attorney Damon P. Martinez of the District of New Mexico. “In addition to requiring crucial cleanup work, the settlement includes important measures to prevent further contamination of the environment and provides for extensive monitoring to ensure compliance.”

“Protecting precious water resources is essential to the health of New Mexico’s communities and the state’s economy,” said EPA Regional Administrator Ron Curry. “While mining pollution is a complex issue, EPA and our partners are pleased to see the next phase of the cleanup at the Questa site take shape.”

“This $143 million cleanup is a powerful example of regulatory protections that work,” said Acting Secretary Butch Tongate for the New Mexico Environment Department. “In addition to the $112 million already collected for environmental work during this administration, the State of New Mexico is pleased with the enforcement of regulations that hold Chevron Mining accountable for the environmental impacts caused by the now-closed Questa Mine which will foster a renewed Questa/Red River destination area.”

The proposed partial consent decree, if approved by the court, will provide for the next phase of the cleanup at the former mine site. It is the largest settlement of its kind for cleanup work in EPA Region 6. CMI has already completed a number of response projects at the site under previous agreements with EPA, including the cleanup of Eagle Rock Lake and the removal of numerous tailing spills. The new work will improve efforts to permanently prevent contamination from the site from affecting the Red River and other water resources and further reduce risks for nearby communities and the surrounding environment. This includes covering and revegetating about 275 acres of the tailings facility, improving and installing new systems that prevent contaminated water from reaching the Red River and operating and maintaining a water treatment plant. The settling parties will also monitor the remedy’s long-term effectiveness at reducing risks to human health and the environment.

The proposed settlement announced today follows on a September 2015 consent decree entered into by the United States, on behalf of the U.S. Fish and Wildlife Service of the Department of the Interior and the Forest Service of the Department of Agriculture, and the State, on behalf of the New Mexico State Office of Natural Resource Trustee, resolving claims for natural resource damages at the Site. Under that consent decree, CMI paid more than $4.2 million for restoring, replacing or acquiring natural resources damaged by mine activities. The current consent decree addresses separate claims from the natural resource damages consent decree.

The Chevron Questa Mine, previously known as the Molycorp Mine, operated intermittently from 1919 until 2014, when CMI permanently closed the mine. Mining operations and waste disposal contaminated soil, sediment, surface water and groundwater. While the mine was operating, approximately 328 million tons of acid-generating waste rock were excavated and deposited in nine large waste rock piles. After molybdenum was extracted from ore, the tailing was transported by pipeline to a tailing facility where it was deposited in tailing impoundments.

The cleanup is being accomplished under the federal Comprehensive Environmental Response, Compensation and Liability Act, commonly known as Superfund. The Superfund law protects human health and the environment while safeguarding taxpayer dollars by holding parties that contributed to contamination responsible for cleaning it up. Since 1980, EPA’s Superfund program has managed the cleanup of the nation’s most hazardous waste sites and has responded to environmental emergencies, oil spills and natural disasters.

The public has the opportunity to submit written comments on the consent decree, which is subject to the 30-day comment period and final approval by the court. A copy of the consent decree is available at www.justice.gov/enrd/consent-decrees.