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.
10/6/05: 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. ERRS began excavation around former mill buildings. Brought in mini-excavator for the day to help w/ excavation around buildings. OSC Weigel returned to Boise.
10/7/05: Personnel on site: 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 2 dozer D6; 1 haul truck 40-ton; 1 water truck; 1 mini-excavator. ERRS completed pulling back side slopes of tailings pile to 3:1 and shaping top of pile. ERRS completed excavation around former mill buildings. Mini-excavator demob.
10/10/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. RPM Matt Wilkening mobilized to site as OSC representative for Weigel. ERRS began placing cover material on tailing pile. Working from staged piles of cover material around the pile. One dozer decon'ed and waiting to be picked up. The second haul truck arrived on Sunday.
10/11/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. ERRS continued placing cover material on tailing pile. First 1-foot lift is high clay content material previously stockpiled on site by property owner. First 1-foot lift compacted using loaded haul trucks. All stockpiled cover material has been used. Began hauling cover material from barrow site on the hillside for final 1-foot lift of topsoil.
10/12/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. ERRS continued placing cover material on tailing pile. Jute netting arrive in AM.
10/13/05: Personnel on site: 1 EPA; 8 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. ERRS continued placing cover material on tailing pile. Dozer that had been deconned on 10/8 removed from site today. One ERRS employee demob'ed from site.
10/14/05: Personnel on site: 1 EPA; 7 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. ERRS continued placing and compacting cover material on tailing pile. OSC Rep. Wilkening demob'ed for Boise.
10/15/05: Personnel on site: 7 ERRS contractor. Equipment on site: 2 excavator 330; 1 front loader 938; 1 dozer D6; 2 haul truck 40-ton; 1 water truck. ERRS completed placement of cover on tailings pile. Reclaimed topsoil barrow area. Decon'ed equipment. 2 ERRS personnel demob'd from site.
10/17/05: Personnel on site: 1 EPA; 5 ERRS contractor. All equipment off rent except 1 excavator and 1 haul truck. OSC Weigel re-mob'ed to site. Revegetation subcontractor arrived and broadcast fertilizer over tailings pile cap and applied specified seed mix (native grasses and forbs) using a no-till drill seeder. Seed was spread by hand along toes of slopes. ERRS began laying out and anchoring jute erosion control matting over seeded side slopes. Re-vegetation subcontractor completed work.
10/18/05: Personnel on site: 1 EPA; 5 ERRS contractor. All equipment off rent except 1 excavator (used for loading jute netting). ERRS completed placement and anchoring of jute netting on seeded 3:1 side slopes. All ERRS personnel except 1 demob'ed from site. OSC demob'ed.
Revegetation subcontractor to return on 10/19 to apply straw mulch over seeded tailings pile. Survey subcontractor to conduct topographical site survey of tailings pile on 10/19, for as-built drawings of completed work. Fencing subcontractor to install approximately 270 feet of three-strand barbwire fence at toe of tailings pile along Broadford Road, to keep snowmobilers and 4-wheelers from riding up onto the tailings pile from Broadford Road.
Need to have discussion with Idaho DEQ and Blaine County regarding appropriate institutional controls to ensure the integrity of completed cleanup work into the future.
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