The historic Ruth Mine mill tailings were the result of a historic mining and milling activity in the Homewood Canyon Mining District, which was mined for its gold lode deposits during the early 1900’s to 1950’s time period. The Ruth Mill was constructed during the 1920s-1930’s period ’ with a rotary ball mill-cyanidation tank circuit. The mill tailings were produced by the rotary ball milling operations.
Approximately +20,000 tons of mill tailings were generated by mining and associated milling operations. These mill tailings were discharged from the mill site over a last +50-year period downslope onto the alluvial fan surface adjacent to Homewood Creek and a residential area downstream. The largest tailings pile forms an elongate-shaped deposit that is eroding into Homewood Wash. The Ruth Mine tailings contain elevated levels of arsenic.
Significant potential human health risks to the community and regional environmental impacts may have resulted from release of arsenic-bearing tailings into the waters of the state and airborne sources. The Ruth Mine have been designated as an AML CERCLA site. Sediments sample results indicate that elevated arsenic levels exist on the hillslope below the mill and steam and floodplain sediments. Monitoring water wells were drilled during 2007-2008 in the Homewood Canyon area adjacent and downstream from the mine.
A preliminary site inspection was undertaken during April 2006, when elevated concentrations of arsenic were detected in the mill tailings material. This survey was followed up by a detailed CERCLA investigation resulting in the compilation of a Removal Site Inspection (RSI) during 2007-2008 document. An Engineering Evaluation/Site Evaluation (EE/CA) document was compiled by an environmental contractor during 2008-2009.
The Engineering Evaluation/Site Evaluation document several remediation options including and capping excavation and consolidation of mill tailing wastes. A mill tailings capping proposal would minimize runoff onto adjacent lands during storm events as well as minimize air-borne transport of arsenic particulate material. The capped mill tailings would be recontoured with native soil and then reseeded with native plants. A post-remediation monitoring and sampling program would be implemented to determine effectiveness of remediation efforts. No selection of a preferred remediation alternative has been made to date.
Risks: Water quality, Arsenic contamination
Location: Section 4, T23S, R43W, SBBM, Inyo County, CA
Field Office: Ridgecrest
Congressional District: 25