Contractors will begin work again to complete stabilization work started last fall at the Gold King Mine near Silverton, Colorado.
This work involves the continued stabilization of the mine adit, as well as additional stabilization of the mine waste pile located in front of the adit. The Environmental Protection Agency’s (EPA) contractor started work July 9 and will continue through October.
Gold King Mine waste water spill was a 2015 environmental disaster. EPA personnel along with workers for Environmental Restoration LLC caused the release of toxic wastewater when attempting to add a tap to the tailing pond for the mine.
Workers accidentally destroyed the plug holding water trapped inside the mine, overflowing the pond, spilling 3 million gallons of mine waste water and tailings, including heavy metals such as cadmium and lead, and other toxic elements into Cement Creek, a tributary of the Animas River in Colorado.
The EPA anticipates the interim water treatment plant at Gladstone will continue to capture and treat any discharge from the mine. However, should any of this work impact downstream watersheds, EPA will notify stakeholders in accordance with the Gold King Mine Stakeholders Alert and Notification Plan available on the EPA’s website.
The planned work activities include:
• Continue work outside of the Gold King Mine (GKM) adit and portal by installing steel bracing and concrete.
• Work with San Juan County to develop a plan for managing road dust from vehicle traffic related to cleanup activities.
• Implement the GKM Stakeholders Alert and Notification Plan with updates as needed.
• Continue to operate the interim water treatment plant (IWTP) at Gladstone to treat discharge from GKM adit.
• Remove solids from the retention ponds and filter bags at the IWTP and place them in the nearby drying area, constructed in June 2016.
• Transport and dispose of dry solids from the IWTP at a local repository (if one is available) or landfill.
• Conduct an analysis of alternatives to continued operation of the IWTP and engage the public in the process.
EPA issued a memorandum in March 2016 establishing a consultation process to help its regional offices prepare for work at hardrock mining and mineral processing sites with possible fluid hazards. The memo includes precautionary measures intended to prevent the type of event that occurred at GKM on Aug. 5, 2015, including headquarters technical consultation.
The consultation process for GKM has been completed, including review of site-specific work plans, a technical assessment of the potential for a fluid release, and verification of a carefully designed and coordinated contingency plan.