The Environmental Protection Agency has a “laundry list of activities” the agency would like to see completed this summer at the Superfund site near Silverton, including monitoring at several key mines.
Last September, the EPA formally listed the Bonita Peak Mining District as a Superfund site to address 48-mining related sites believed responsible for degrading water quality in the Animas River.
During the summer and fall, the EPA begin preliminary investigations on the hydrology in the Animas River basin, taking water samples, studying mine sites and pinpointing sites the agency could immediately address while long-term solutions are evaluated.
At the Animas River Stakeholders Group meeting in Silverton on Thursday, Superfund site project manager Rebecca Thomas told the 20 or so attendees the EPA has laid out a work plan for the summer.
Thomas said much of the work will be a continuation of last year’s activities, including collecting data and water samples, as well as looking at flow control structures at the Gold King Mine, the site of the EPA-triggered mine spill in August 2015.
The EPA also will install a pressure gauge system to monitor the bulkhead at the Mogul Mine, adjacent to the Gold King, which are both significant contributors of heavy metals into Cement Creek, a tributary of the Animas River.
The EPA wants to install a ground monitoring well between the inner and outermost bulkheads at the American Tunnel, the drain for the Sunnyside Mine workings. It’s suspected the American Tunnel’s water level has reached capacity and could be responsible for increased discharges out of adjacent mines, such as the Gold King.
Thomas said crews will compile more data for the possible closure of the bulkhead at the Red & Bonita Mine, another contributor into Cement Creek. Specifically, EPA wants to better understand the water hydrology of the mine workings.
As for the EPA’s interim water-treatment plant at Gladstone that treats discharges out of the Gold King Mine, Thomas said the agency is looking at about six sites to store the mine waste.
“This is increasingly more important for us as we start to run out of room for sludge management (at Gladstone),” Thomas said.
She said there may be more than one location for the mine waste, and that the agency hopes to have that finalized by May.
Thomas added that the EPA is planning a few quick-action remediation projects at sites within the Superfund listing where there is an immediate benefit to the environment, water quality and managing adit discharges.
She said 27 of the 48 sites qualify for early-action remediation, which could include fixing mine waste ponds, remediating waste rock dumps or redirecting clean surface water away from known polluted areas.
“There’s no way we’re going to get all the work done, but the hope is to get some of the work done,” Thomas said.
The Bureau of Land Management, Colorado Department of Public Health and Environment and the U.S. Forest Service – all working on the Superfund site – also listed a few projects they have planned for this year.
Most notably, the BLM has permission to undergo a pilot project with Texas-based Green Age Technologies to test a new treatment on mine wastewater that many in the stakeholders group have said holds promise for low-cost water treatment.
The BLM and Green Age will spend 21 days treating discharges out of the American Tunnel and Gold King Mine with a technology known as cavitation, which separates metal ions from water.
The EPA had promised the town of Silverton before the community supported Superfund designation that the agency would embrace new technologies for mine-waste treatment.
