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September 23, 2015: EPA Announces Gold King Mine Water Treatment System for Winter 2015-16

Sept. 23, 2015

(Washington, D.C.) -- The U.S. Environmental Protection Agency (EPA) announced today that a portable, temporary treatment system will be located in Gladstone, CO to continue treating water discharged from the Gold King Mine during winter 2015-16. This system will replace temporary settling ponds constructed by the EPA in August 2015.

The transition to the portable treatment system is necessary as winter temperatures at the mine site (elevation 10,500 feet) can reach -20F, making it unsafe to manually treat water at the mine site. The schedule calls for the treatment system to be operational by Oct. 14, 2015. EPA’s contractor, ER LLC, awarded a subcontract Sept. 22, 2015 to Alexco Environmental Group (US) Inc. to complete the work.

This system will treat the approximately 550 gallons per minute (gpm) of water that continue to flow from the mine, including the discharges related to ongoing work in the mine to stabilize conditions. The system is designed to handle up to 1,200 gpm. The objective of the treatment system is to neutralize the mine discharge and remove solids and metals. Although the Gold King Mine discharge is just one of many into Cement Creek, the treatment will remove a portion of the metal loading to Cement Creek.

The EPA continues to evaluate data to determine the impact of the Gold King Mine on water quality.