Minnie Mine

Mining claims associated with the Minnie Mine facility were staked by Fred Higby, who operated a small cyanide leach plant in 1982. The cyanide heap leach operation was later operated by Cordilleran Development, Inc., which ceased mining in 1986. During operation, the plant consisted of three process ponds, two leach pad liners, a process plant building, and the open pit mine itself.

As a result of the death of several livestock at the site, Ecology issued a series of enforcement orders requiring remedial action.  These activities resulted in the construction of a soil cap over contaminated ore and other process materials. 
 
As a result of soil contamination remaining at the site, the United States Forest Service placed institutional controls in the form of internal land use restrictions on the property. These land use restrictions prevent the disturbance of the soil cap, and prevent any land use which may result in the release of contamination contained within the soil cap.

Based upon cleanup activities conducted and the institutional control at the site, Ecology has determined the site is no longer a threat to human health and the environment.

Periodic reviews are conducted every 5 years by Ecology for sites that have institutional controls. The review is intended to examine the effectiveness of cleanup activities and to assure the continued protection of human health and the environment.

Periodic Review Results

Soils with metals concentrations higher than Model Toxics Control Act (MTCA) Method A cleanup levels are still present. Institutional controls in the form of USFS land use restrictions protect the integrity of the soil caps present at the site.

The remedial actions conducted at the site appear to be protective of human health and the environment.

Based on the periodic reviews, Ecology has determined that the requirements of the institutional controls are being satisfactorily followed. No additional remedial actions are required by the property owner. It is the property owner’s responsibility to continue to inspect the site to assure that the integrity of the cap is maintained.