LEAD, S.D. — Production and sales were down about 20% last year at the only active, large-scale gold mine in the Black Hills, according to reports filed with state regulators.

An annual report by Coeur Mining that was reviewed recently by the state Board of Minerals and Environment shows that Coeur’s Wharf Mine near Lead produced 76,840 ounces of gold last year, down 19.4% from 2017, the Rapid City Journal reported.

The mine also produced 50,575 ounces of silver last year, down 20.4% from the previous year.

Matt Zietlow, environmental manager at the Wharf Mine, said difficult conditions at the mine caused by a wet summer and snowy winter influenced production.

“If you have to put a lot of resources into making the mine safe again and making roads passable again, you’re taking people away from their regular jobs,” Zietlow said, “and that will impact things for a little while.”

Coeur’s annual report to investors for 2018 said combined sales of gold and silver from the Wharf Mine were $96.5 million in 2018, which was down 23% from $125.9 million the previous year.

Coeur’s gold and silver is refined into bullion and sold to multinational banks, bullion trading houses and refiners around the world.