BUTTE, Mont. (AP) — Montana and federal officials have reached a tentative agreement on the removal of more contaminated mine waste around Butte.
The U.S. Environmental Protection Agency expects to finalize the agreement by the end of the year, the Montana Standard reported Friday. It includes the removal or containment of mine waste and the creation of stormwater retention ponds along Upper Silver Bow and Blacktail creeks.
Beginning in the 1800s, crews working Butte's massive network of copper mines dumped mining waste into streams and wetlands around the city.
Emergency cleanup work on some of the contaminated sites began in the 1980s.
Negotiations over the remaining cleanup have been ongoing between the EPA, Montana, and BP, the parent company of Atlantic Richfield Company, since 2009.
In disclosing the agreement, officials said the parties were changing the structure of the negotiations to get more public input. That's a departure from previous confidential negotiations in which comment was solicited from the public only after a final agreement was reached.
EPA Region 8 Administrator Shaun McGrath stressed that more negotiations will be needed on each of the points being discussed.
"The devil is in the details," he said, adding that "all of the points are being discussed concurrently" in the negotiations. "When we have agreement on one, we will share it with the public."
Some of the work, to remove the Parrot mine tailings waste, is projected to start in late summer or early fall, DEQ director Tom Livers said.
Atlantic Richfield Company became responsible for Butte mining damage after it purchased The Anaconda Copper Company in 1977. As of last year, the company said it had paid the state $74 million to settle lawsuits, including money for removing the tailings.
A 2010 study showed that an underground plume of contaminated water linked to the Parrot mine had arsenic levels at more than 10 times the drinking water standard and copper levels at more than 7,500 times the standard.
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