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A California gold mine’s toxic legacy: Inside the fight over reopening a treasure trove

For five years Rise Grass Valley has been trying to get a permit, but the people of Grass Valley are overwhelmingly rejecting the mine. And CEO Ben Mossman.


Below are a few excerpts. Read the full column in LA Times. Or, watch the news coverage from SpectrumNews1.



Like many of California’s estimated 47,000 abandoned mines, the Idaho-Maryland has a toxic legacy. To get the mine running again, Rise Grass Valley would have to drain its flooded tunnels and continuously pump groundwater from it. Mossman says the treated water will be “better than drinking water” and that the mine will actually create a surplus of much-needed water that could be used for agriculture and other needs. But detractors are leery of a project that requires pumping groundwater as California is in the midst of climate change and an extreme drought that is adding to strains on underwater aquifers. Elsewhere in the state — most famously the Central Valley — overpumping has caused land to sink.

Before coming to Grass Valley, Mossman was the president and chief executive of a company called Banks Island Gold. It ran the Yellow Giant gold mine on remote Banks Island off the coast of British Columbia, on the traditional land of the Indigenous Gitxaala Nation — which long opposed the mine because of potential pollution. Mossman started mining there in 2014. But after he received complaints, provincial inspectors showed up the next year and found that his company was releasing mine waste and contaminated water into creeks, ponds and wetlands. Mossman and his chief geologist are currently on trial in British Columbia on nine federal and 20 provincial charges related to spills at the mine, a spokesman for the British Columbia Prosecution Service said.

Inside his company’s small Grass Valley office, green-and-gold yard signs for potential mine supporters proclaim: YES! IDAHO-MARYLAND MINE. But if they are displayed around town, they are hard to find.

Meanwhile, on front lawns and in storefront windows, black-and-gold signs scream: PROTECT OUR AIR, WATER, QUALITY OF LIFE. NO MINE.

If it reopens, mining will commence on the ancestral homeland of the Nevada City Rancheria Nisenan Tribe, who were brutalized and forced off their land during the Gold Rush. Shelly Covert, a spokeswoman for the tribe, said she was stunned to hear the mine could be reopened. Like the Gitxaala people in Canada, the Nisenan don’t want Mossman’s mine because of the harm it could do to the environment. “This land is just starting to revive,” she said. “They’re saying, ‘The science is great now. We don’t have to worry about anything.’ I still almost get speechless because I think it’s just so irresponsible.” “The county is so naive in trying to assist this group to gain status,” Mossman wrote. Then he sarcastically alluded to the tribes of the Great White North, where the Gitxaala could not stop his last mine from opening. “Welcome to Canada.”

Hailey Branson-Potts is a Metro reporter for the Los Angeles Times who joined the newspaper in 2011. She grew up in the small town of Perry, Okla., and graduated from the University of Oklahoma. Times researcher Jennifer Arcand contributed to this report.


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