DENVER — The U.S. Environmental Protection Agency fired back Thursday after a mining company accused the agency of failing to run a southwestern Colorado treatment plant at full capacity, letting untreated mine wastewater get into the Animas River.

EPA officials said the plant is running the way it was designed to, treating wastewater pouring from the inactive Gold King Mine. Scrubbing wastewater from additional sites would require expanding the plant, they said.

The exchange was the latest in a dispute between the agency and Sunnyside Gold Corp. over who should pay for a water study to help devise a cleanup plan for the area.

Doug Benevento, the EPA’s Denver-based regional director, said Sunnyside’s criticism of the treatment plant is designed to distract attention from the company’s responsibility to help with the cleanup.

“It’s unfortunate that instead of cooperating … they distract and try to point fingers back at us,” Benevento said, who was appointed by EPA Administrator Scott Pruitt.

Sunnyside said it isn’t responsible for the ongoing pollution problems.

“The fact is, (Sunnyside) is not the cause of water quality issues in the Animas River,” spokesman Larry Perino said in an email to The Associated Press Thursday.

The EPA designated the area a Superfund site in 2016, including Gold King and 47 other mining-related sites that are sending wastewater into the Animas.

The designation came a year after an EPA-led contractor crew inadvertently triggered a massive wastewater spill while excavating at an entrance to the Gold King. The spill sent a yellow-orange plume of toxic heavy metals into rivers in Colorado, New Mexico, Utah and on Native American lands.

Last month, the EPA ordered Sunnyside to pay for a study of underground water in part of the district. The company doesn’t own the Gold King Mine, but it does own several other sites in the Superfund district. The EPA said that makes the company a “potentially responsible party” under federal law.

Sunnyside argues it’s not liable for current pollution because it complied with state and court orders for cleaning up its sites. The company maintains the EPA endorsed the arrangement, but the agency disputes that.


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