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Gladstone WTP

Site Contact:
Kerry Guy
On-Scene Coordinator


Site Location:
Silverton, CO 81433

Click here for sampling data (PDF format) during the IWTP shut down from March 14-16.

Click here for sampling/monitoring data (Excel format) during the IWTP shut down from March 14-16.

On August 5, 2015, 3 million gallons of mine influenced water was unexpectedly released from the Gold King Mine. Since October 2015, EPA has collected and treated discharge from the Gold King Mine at the Interim Water Treatment Plant (IWTP) at Gladstone, Colorado. As of June 2018, the IWTP has treated approximately 800 million gallons of Gold King Mine water. The IWTP is located about 9 miles north of Silverton, Colorado, in the Cement Creek drainage. Both the Gold King Mine and the IWTP are in the Bonita Peak Mining District Superfund Site.

The Gladstone IWTP removes metals in the mine impacted water through a lime neutralization, precipitation, and flocculation process. This process produces treatment solids, or sludge. Since the IWTP began operations, sludge generated by the treatment process has also been managed at that location.

However, all the available sludge storage capacity at the IWTP has now been filled, and EPA has identified another location where the additional sludge can be managed. In cooperation with the property owner, the new interim sludge management location will be established at the Kittimac Tailings source area, approximately 6.5 miles northeast of Silverton, along County Road 2.

EPA will mix the non-hazardous sludge with mine tailings located at Kittimac. This will reduce the high water content of the sludge and allow it to be more efficiently managed. A secondary benefit will be to immobilize heavy metals found in the tailings.

EPA completed approximately 75 percent of sludge management at the interim Kittimac repository by October 2018. The work will commence in Spring 2019.

For additional information, visit the Notices section.

A Map is available for viewing GIS information.