DENVER (AP) — The Environmental Protection Agency said Wednesday it will set up a temporary treatment plant for wastewater flowing from the Gold King Mine in southwestern Colorado after 3 million gallons surged out of the mine in August, tainting rivers in three states.
Colorado's two U.S. senators urged the agency to build a longer-term plant to treat acidic water flowing from multiple mines in the Upper Animas River watershed around Silverton, saying pollution from inactive shafts is a serious problem across the West.
The EPA said it needs the temporary plant for the Gold King Mine because it will be unsafe to operate the settling ponds that are now in use when winter temperatures fall below zero.
The $1.8 million facility is expected to start operating by Oct. 14 and run for up to 42 weeks. The EPA said it will cost $20,000 a week to operate.
The plant would be portable, but EPA spokeswoman Christie St. Clair said she couldn't immediately provide details.
The EPA released documents last week saying it was considering the plant.
St. Clair said the EPA will decide whether to set up a longer-term treatment plant after a more detailed evaluation of other leaking mines in the Upper Animas River watershed. Underground water commonly seeps into inactive mines that perforate the mountainsides, and it often overflows from the mine openings.
Democratic Sen. Michael Bennet and Republican Sen. Cory Gardner urged the EPA to build a long-term plant, citing four inactive mines in the watershed that release a combined 330 million gallons of acidic wastewater every year — far more than the Gold King blowout.
In a letter to EPA Administrator Gina McCarthy, the senators said experts believe a treatment plant is the best initial step to deal with the problem. They asked her to make it a priority.
The letter was dated Tuesday and made public Wednesday.
An EPA-led cleanup crew inadvertently triggered the Gold King Mine blowout Aug. 5 when heavy equipment breached a debris dam holding back wastewater containing heavy metals. The water flowed into rivers in Colorado, New Mexico and Utah, including the Southern Ute Reservation and the Navajo Nation.
Utilities and farmers shut down drinking water intakes and irrigation canals. The EPA has said the water quality has returned pre-spill levels, but some officials have concerns about pollution lingering in sediment and have expressed doubts about the EPA's statements.
The EPA said water was flowing from the mine before the blowout and continued afterward.
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