Grass Valley, CA – In the heart of the historic Gold Rush area, Grass Valley is no stranger to legacy contamination from gold mines, but holding companies accountable for fixing the contamination has proven to be no small feat. Community Environmental Advocates Foundation (CEA Foundation) is working to change that. A Canadian-headquartered company, Rise Gold Corp., purchased the Idaho- Maryland gold mine property in 2017 in hopes of reopening the mine, but were denied a permit by Nevada County Supervisors in 2024 due to extensive concerns about unmitigated risks to the surrounding community. Unfortunately, the project denial also killed prospects of cleaning up some of the toxic mine waste residues left over from the past century, including acres of contaminated mine tailings and ongoing polluted mine drainage into local creeks.

After losing their bid to open the mine, Rise Gold abandoned an agreement with the California Department of Toxic Substances Control to clean up the mine tailings. And without the approval of the mine, the prospect of an interim solution to the polluted drainage into the creeks was also lost.

Dealing with the creek pollution is now firmly on CEA Foundation’s radar. The contaminated mine water flows from the Idaho-Maryland Mine into Wolf Creek near central Grass Valley. To address the problem, CEA Foundation has filed a lawsuit against Rise Gold Corp and its subsidiary Rise Grass Valley (Rise) for violations of the Clean Water Act. The lawsuit requires Rise to obtain a National Pollution Discharge Elimination System permit (NPDES) to address the problem. A 60-day Notice Letter was sent to Rise on September 5, 2024. To avoid litigation, additional time was provided by CEA for Rise to commit to obtaining a permit, but without success. As a result, the legal complaint was filed in U.S District Court in Sacramento on December 20, 2024, but CEA is still hoping for – and working towards – a voluntary resolution.

The mine drains the polluted water from the flooded Idaho-Maryland Mine directly into the main branch of Wolf Creek at several points near Centennial Drive. The contamination is well documented. For example, test results in a document provided for Rise’s own environmental studies, “Groundwater Hydrology and Water Quality Analysis Report for the Idaho-Maryland,” EMKO, February 2021, show that the mine effluent contains arsenic, ammonia, and other contaminants exceeding safe thresholds.

And an April 2019 Environmental Protection Agency (EPA) Site Inspection Report shows mine drain outflows have high levels of Arsenic, Barium, Chromium, Cobalt, Copper, Lead, Manganese, Nickel, and Zinc.

Rise had applied for a Use Permit in 2019 to de-water and conduct mining. Although a mine-water treatment system was part of Rise Gold’s failed attempt to open the mine, the proposed treatment system also failed to adequately address the mine drainage into Wolf Creek. This contaminated drainage, which has been a source of pollution since the mine refilled with water after mine closure in 1956, will likely require a treatment facility running in perpetuity.

The CEA Foundation lawsuit requires that Rise obtain a NPDES permit and cease violating the Clean Water Act, taking a key step towards developing a long term solution that restores clean water flowing into Wolf Creek now and into the future.

Community Environmental Advocates Foundation (CEA Foundation) advocates for responsible land use and environmental protection policies and actions in Nevada County. Our goal for Nevada County’s future is a thriving community, a sustainable economy, and a healthy environment.

CEA Foundation

PO Box 972, Cedar Ridge CA 95945
website: https://www.cea-nc.org
email: info@cea-nc.org