EPA knew of 'blowout' risk for tainted water at gold mine

Anger Swells at EPA Over Toxic Gold Mine Spill

WASHINGTON (AP) — Internal documents released late Friday show managers at the U.S. Environmental Protection Agency were aware of the potential for a catastrophic "blowout" at an abandoned mine that could release "large volumes" of wastewater laced with toxic heavy metals.

EPA released the documents following weeks of prodding from The Associated Press and other media organizations. EPA and contract workers accidentally unleashed 3 million gallons of contaminated wastewater on Aug. 5 as they inspected the idled Gold King Mine near Silverton, Colorado.

Among the documents is a June 2014 work order for a planned cleanup that noted that the old mine had not been accessible since 1995, when the entrance partially collapsed. The plan appears to have been produced by Environmental Restoration, a private contractor working for EPA.

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EPA knew of 'blowout' risk for tainted water at gold mine
DURANGO, CO - AUGUST 7: The Animas River flows through the center of Durango on August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
SILVERTON, CO - AUGUST 7: Water flows into pits of mine wastewater below the Gold King Mine on August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 7: Kalyn Green, resident of Durango, stands on the edge of the river August 6, 2015 along Animas River. 'I come down to the river every morning before work.' said Green. 'The river in a sense of calm for me.' Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 7: People get their first look at the Gold King Mine wastewater that flowed into the Animas River August 7, 2015 at the 32nd Bridge. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
SILVER TON, CO - AUGUST 7: Water runs through the land that was damaged by the mine wastewater spill August 7, 2015 along Animas River. A crew from Environmental Restoration is on the scene and is flushing water over the land and doing construction on the site. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 7: Mack Goshorn, from Loveland, looks out over the city of Durango on August 6, 2015 along Animas River. Goshorn, a resident of Durango from 1941 to 1955, came back to the city for a funeral of a high school friend. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 7: The Animas River flows through the center of Durango on August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
SILVERTON, CO - AUGUST 7: Mine wastewater pours out of pipes August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 7: Mine wastewater washes up on shore August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
SILVERTON, CO - AUGUST 7: Mine wastewater empties into pits below the mine August 7, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 8: Trisha Rickey sits near the shore of the Animas River after taking pictures of the river August 8, 2015. Over a million gallons of mine wastewater from the Gold King Mine in Silverton has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 8: Abby Leatherman and Clifford Field work on cleaning a boat that is done for the season August 8, 2015 at Mild and Wild. Three of the 38 guides that are employed at Mild and Wild showed up for work today since all recreational use on the Animas River has been halted since the spill. Over a million gallons of mine wastewater from the Gold King Mine in Silverton has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 6: Residents wait as water comes back in anticipation of the mine wastewater coming downstream August 6, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
DURANGO, CO - AUGUST 6: Residents sit on the edge of the river while waiting a glimpse of the mine wastewater that spilled into the river earlier in the day August 6, 2015 along Animas River. Over a million gallons of mine wastewater has made it's way into the Animas River closing the river and put the city of Durango on alert. (Photo By Brent Lewis/The Denver Post via Getty Images)
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"This condition has likely caused impounding of water behind the collapse," the report says. "ln addition, other collapses within the workings may have occurred creating additional water impounding conditions. Conditions may exist that could result in a blowout of the blockages and cause a release of large volumes of contaminated mine waters and sediment from inside the mine, which contain concentrated heavy metals."

A subsequent May 2015 action plan for the mine also notes the potential for a blowout.

There are at least three ongoing investigations into exactly how EPA triggered the disaster, which tainted rivers in Colorado, New Mexico and Utah with lead, arsenic and other contaminates. EPA says its water testing has shown contamination levels have since fallen back to pre-spill levels, though experts warn the heavy metals have likely sunk and mixed with bottom sediments that could someday be stirred back up.

The documents, which the agency released about 10:30 p.m. eastern time, do not include any account of what happened immediately before or after the spill. The wastewater flowed into a tributary of the Animas and San Juan rivers, turning them a sickly yellow.

Elected officials in affected states and elsewhere have been highly critical of the EPA's initial response. Among the unanswered questions is why it took the agency nearly a day to inform local officials in downstream communities that rely on the rivers for drinking water.

Much of the text in the documents released Friday was redacted by EPA officials. Among the items blacked out is the line in a 2013 safety plan for the Gold King job that specifies whether workers were required to have phones that could work at the remote site, which is more than 11,000 feet up a mountain.

EPA did not immediately respond Friday night to questions from the AP. In the wake of the spill, it has typically taken days to get any detailed response from the agency, if at all.

On its website, contractor Environmental Restoration posted a brief statement last week confirming its employees were present at the mine when the spill occurred. The company declined to provide more detail, saying that to do so would violate "contractual confidentiality obligations."

The EPA has not yet provided a copy of its contact with the firm. On the March 2015 cost estimate for the work released Friday, the agency blacked out all the dollar figures.

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