On August 5 the EPA was conducting an investigation of the Gold King mine. The agency says “the intent of the investigation was to assess the on-going water releases from the mine and to treat mine water and to assess the feasibility of further mine remediation. The plan was to excavate the loose material that had collapsed into the cave entry back to the timbering. During the excavation, the loose material gave way, opening the adit and spilling the water stored behind the collapsed material into Cement Creek, a tributary of the Animas River.
“Initial estimates are that the release contained approximately one million gallons of water (estimated from the dimensions of the mine adit) that was held behind unconsolidated debris near an abandoned mine portal. There were several workers at the site at the time of the breach, all were unharmed.
“The large pulse of water dissipated in about an hour. The water in Cement Creek and the Animas River in Silverton is [now] clearing. The adit is still discharging lower flows into Cement Creek. EPA is rebuilding settling ponds to treat these flows. EPA will treat the mine water diverted to the ponds with caustic soda and flocculent once the ponds are built.
“EPA Region 8 has been coordinating with Region 6 and Region 9 and the states of Colorado, New Mexico, Utah, and the Southern Ute Tribe. Region 6 is working closely with the New Mexico Environment Department to evaluate possible impacts in New Mexico. Potentially impacted water systems have been notified and precautions are in place to ensure drinking water in homes is protected. EPA and NMED are providing assistance to community water systems and closely monitoring the situation.”
Next steps:
- Continue to treat drainage at mine site
- Continue to sample the Animas River corridor
- Evaluate and publish data as it is finalised
- Continue coordination with State, Federal, Tribal and local officials as well as community members, landowners/ water users
- Continue to provide drinking water and water testing to private well owners.