LEAD, S.D. – The state Board of Minerals and Environment unanimously endorsed the expansion of the Coeur Wharf Resources mine, just north of Terry Peak and west of Lead, during its Thursday meeting in Pierre.
The action is contingent on the later submission of surety bonds and conditions that the mining company address and mitigate a surface water quality violation on its property. The violation is caused by excessive amounts of selenium, which is a naturally occurring mineral in soil that can pollute water and be harmful to people and fish in great amounts.
The department first noticed increases in selenium in False Bottom Creek, which is on Wharf property, in 2014 and sent a warning letter to Wharf in 2021. Wharf had begun depositing rock at the site in an effort to reclaim an area no longer used for the mine, though Wharf Environmental Manager Matt Zietlow previously said it was “unknown” if Wharf caused the problem.
The board members at their Thursday meeting continued a hearing that was held two months ago regarding Wharf’s expansion, which is expected to extend the mine’s life by one to three years, or until 2028 or 2030. The mine was granted four other expansion permits in its 40-year history, the latest in 2011.
The expansion will disturb an estimated 31.9 million tons of material, including 6.7 million tons of ore and 25.2 million tons of overburden and non-mineralized rock. Wharf’s 2022 gold and silver sales totaled over $150 million, and its net income was over $34 million. Wharf paid about $4.3 million in state mineral severance taxes last year.
The board heard testimony in May from Wharf, the Department of Agriculture and Natural Resources and Rapid City-based activist Carla Marshall, who filed as a formal intervenor to oppose the expansion.
The conditions of the permit include a timeline to treat selenium amounts in False Bottom Creek to meet required selenium limits by 2025, and a requirement to submit monthly updates to the department. It also requires that Wharf submit an annual surface and groundwater characterization report.
Board member Gary Haag said he would like to see Wharf or the Department of Agriculture and Natural Resources keep the board informed about the schedule and implementation of the treatment system.
The permit conditions will keep the board and the public more informed about the remedies made at False Bottom Creek, Chairman Rex Hagg said.
“Everybody has stepped up to agree to address it, and that’s the main thing,” the chairman said during the meeting. “I feel comfortable that the state’s interest is being served by that.”
The permit will not be officially approved until Wharf presents surety bonds for the expansion, which will be presented to the board at its next meeting later this year.
Wharf did officially object to the department’s statement that it is in violation of the Clean Water Act, saying it did not receive formal notice of the violation and that there hasn’t been a hearing on the violation. The state Department of Agriculture and Natural Resources disputed the claim, saying that the notification was appropriate.
The Wharf Mine is the only active, large-scale gold mine in the Black Hills.
