The Environmental Protection Agency is considering hauling waste from the Gold King Mine outside Silverton more than 70 miles to the Bondad landfill south of Durango because the agency expects it will run out of storage space.
Critics say the proposed plan is not financially or environmentally practical when the cost of hauling and dumping the sludge, including the carbon footprint of all those truck trips, are taken into account.
“You may be getting some zinc out of the water and saving some fish, but think of the environmental damage and carbon footprint,” said San Juan County Commissioner Scott Fetchenhier. “It’s huge.”
But the EPA may be left with no other option.
A temporary water-treatment plant was set up at the cost of $1.5 million in October 2015, just three months after the EPA triggered the Gold King Mine blowout, which sent a torrent of mine waste down the Animas and San Juan rivers.
Since then, the water-treatment plant has been removing potentially toxic metals out of waste discharging from the mine, which continues to leak at about 600 gallons a minute, according to EPA officials.
For years, the standard for treating acidic mine wastewater has been to use a lime treatment to raise the pH of the water so that dissolved metals become solids and can settle in settling ponds.
Lime treatment is highly effective in improving water quality, but the process generates a massive amount of sludge, about 95 percent of which is the lime added to help in the first place. About 5 percent of the sludge is the actual toxic metals. But the sludge as a whole is considered non-hazardous and may be dumped in a landfill.
The EPA’s water treatment plant for the Gold King Mine produces about 4,600 cubic yards of sludge every year, said Cynthia Peterson, an agency spokeswoman.
For the past three years, the EPA has deposited the sludge on-site at the temporary water-treatment plant in an area known as Gladstone, about 6 miles north of Silverton on County Road 110. However, the EPA is likely to run out of storage capacity at the site by July, Peterson said.
The EPA has been actively trying to find other places around Silverton to dump the sludge, namely the Sunnyside tailings pond or the Howardsville site – both existing sites for mine waste – with no success.
Sunnyside Gold Corp. owns the Sunnyside tailings pond. Todd Hennis owns the Howardsville site; he also owns the Gold King Mine. Both are “potentially responsible parties” in the EPA’s Superfund cleanup.
The EPA may be forced to haul the sludge nearly two hours over two mountain passes and through Durango to dump it at the Bondad landfill, about 18 miles south of Durango off U.S. Highway 550.
“Our preference would be to identify options that don’t involve transporting sludge off-site,” Peterson said. “We will continue to coordinate with local officials and agency partners to identify the most appropriate option to manage sludge.”
Fetchenhier agreed the best spot for dumping sludge would be an already affected area in Silverton, but he acknowledged the difficulty in finding a property owner who would be open to the idea.
Still, Fetchenhier, a geologist and former miner, questioned the ultimate benefits of a lime treatment plant. First, the lime has to be mined and then crushed. Then, it has to be hauled 100 miles from Farmington to Silverton. And the cost of the plant is $1 million a year to operate.
Committing to hauling the sludge to a landfill nearly two hours away, and the fees associated with the landfill, is likely to significantly increase the cost of treatment. It also has an environmental impact, Fetchenhier said.
“You’re not winning,” he said. “The carbon footprint and landfill issue is huge. That’s why it needs to stay here.”
The EPA hasn’t made a final decision either way, and it didn’t have specifics about the cost or number of truckloads it would take to transport the waste to the Bondad landfill.
Pete Maisel, a former Silverton Town Trustee who is part of the Silverton/San Juan County Planning Group for the Bonita Peak Mining District Superfund site, questioned why the EPA hasn’t found a suitable place for the sludge.
“It’s been three years, and they still can’t find a repository,” Maisel said.
One suggestion has been to change the chemistry of the sludge and put it back in the mine workings. That process hasn’t been proven as viable, said Peter Butler with the Animas River Stakeholders Group.
“If you change the chemistry of the sludge, then it could come in contact with water and be OK,” Butler said. “But I don’t think people are confident they’re ready to try that process yet.”
Since the water treatment plant went into operation, some have called for the EPA to treat discharges out of the Mogul and Red & Bonita mines, as well as the American Tunnel. The EPA has previously said it is evaluating its options for long-term cleanup solutions in the mining district.