The mill site was active during the 1950's for the production of mercury by reprocessing old mine tailings from adjacent mercury mines in the Griswold Hills area near Panoche Valley, San Benito County. The production records are unpublished, but from the minimal amount of calcines (roasted cinnabar ore) located on the site less than 200 flasks were produced. The site contained two retorts, a water well, two mobile homes, two water tanks, several outbuildings, an old drilling rig, and several pieces of heavy equipment.
Restoration and Final Costs
Site restoration began in the Spring of 2001 and was completed in the Fall of the same year. All salvageable equipment and site debris were removed by the claimant. The calcines and retort bricks were buried on site. The repository was capped, fenced and revegetated. The water well was plugged and officially abandoned. The disturbed areas was recontoured and seeded. Total cost from characterization to restoration was about $10,000.
Risks: Water quality, Hg contamination
AMLIS #: CA021900007
Field Office: Hollister
Congressional District: 17