The Minnie Moore Mine Site presently consists of the 6-acre tailings pile, as well as the remains of the former mill and shop, and a still intact bunkhouse. The main tailings pile is located just south of the site entrance from Broadford Road. It lies on relatively level ground and rises about 20 feet above the original ground surface. The tailings pile is bordered on the east by Broadford Slough, which runs within five feet of the toe of the tailings pile in some places. Lead concentrations in an exposed 6-acre tailings pile at the Site range from 1,400 to 18,500 parts-per-million (ppm). Elevated concentrations of metals exist in nearby soils, including lead concentrations of 4,300 ppm at the former mill building area. The removal action includes the construction of a permanent clean cover for the tailings pile at the Minnie Moore Mine. Other nearby soils containing lead concentrations of 700 ppm or more will be removed and excavated areas will be backfilled with clean fill. EPA and contractor personnel mobilized to the site for cleanup on 9/26/05.
9/29/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck. ERRS continued pulling back side slopes of tailings pile to 3:1 and shaping top of pile.
9/30/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck. ERRS continued pulling back side slopes of tailings pile to 3:1 and shaping top of pile. EPA OSC left site to spend weekend at home. ERRS to continue working 10-hour day on Saturday and take Sunday off.
10/3/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck. EPA OSC re-mobilized to site. ERRS continued pulling back side slopes of tailings pile to 3:1 and shaping top of pile.
10/4/05: Personnel on site: 2 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck. EPA RPM Matt Wilkening arrived on site to review site work. Wilkening will be OSC representative week of 10/10/05, as Weigel has response duty that week. Three Idaho DEQ personnel from Twin Falls office visited site to review site conditions and cleanup progress. ERRS continued pulling back side slopes of tailings pile to 3:1 and shaping top of pile. EPA, ERRS contractor and site property owner examined alternate source of topsoil on site for use as final cover and growing medium for re-vegetation. Determined that we will use this better quality (less rocky) source of topsoil for final 1-foot cover. Using this source will require a longer haul and an additional haul truck than previously anticipated. Already stockpiled soil with high clay content will be used for first 1-foot lift of cap.
10/5/05: Personnel on site: 2 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck. ERRS continued pulling back side slopes of tailings pile to 3:1 and shaping top of pile. EPA met with Blaine County roads and bridges supervisor to discuss requirements along Broadford Road, where toe of tailings pile comes down to road. With reduced side slopes of tailings pile there is concern that traffic, particularly motorcycles and 4-wheel drive vehicles, will ride up onto the tailings pile at the sharp corner of Broadford Road adjacent to the re-configured tailings pile. Agreed that the County will install a warning sign at the corner, and EPA will install barb-wire fence at toe of tailings pile adjacent to road. Wilkening de-mobilized from site.
Continue shaping tailings pile to 3:1 side slopes and 10:1 crown. Continue excavating contaminated soils in former mill area and incorporate on tailings pile. Backfill excavated areas with clean soil. Place 2 foot clean soil cover on tailings pile. Revegetate tailings pile. Projected completion date 10/21/05.
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