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..~ ., (Page 2) MLNE ID # OR PROSPECTING ID # H-80-244 INSPECTION DATE 9/9/94 INSPECTOR'S INITIALS ACS OBSERVATIONS An inspection of the Cresson Project Phase 1 leach pad construction was conducted. . Geomembrane installation on the south side of the Phase 1 pad was underway at the time of this inspection. It was observed that~the electric generators that power the geomembrane welding apparatus were placed on a smooth base in accordance with the approved specifications. Gravelly areas at the exposed surface of the rolled soil component of the composite liner were being covered with a veneer of Carlton tailings. The consistently fine grained Carlton tails provide a very smooth finished eubgrade for the VLDPE. The pad edge anchor trench ie being excavated using the same trencher that was utilized to install the leak detection trenches. The anchor trench is rectangular, and 2.5 feet deep by 2 feet wide at the location inspected. Backfilling of the anchor trench had not yet commenced at the time of this inspection. The location near the Ironclad pit where the soil liner fill ie being screened and detoxified was inspected. The Ironclad tailing material oversize (material coming off the top of the 3 inch screen) is now being placed back onto the main Ironclad tailing pile, rather than being dumped into the Ironclad pit as was occurring previously, and ae was noted in the 8/29/94 inspection report. The hypochlorite application to the soil liner fill ie now occurring at an elevated station above the conveyor belt exiting the screen. The hypochlorite is fed onto the screened ironclad tails ae they pass underneath on the belt; the hypochlorite appears as a white stripe on the top of the mound of conveyed soil. Recent daily and weekly reports prepared by the Construction Quality Assurance Honitor were examined. These were found to be well prepared and highly detailed. The daily reports contained documentation of Golder's observations of toe dam lift placement and compaction, which the Division believes is critical to assure adequate performance of the facility. The reports also document Golder's observations of pressure and vacuum testing of installed geomembrane. The calibration records for hypochlorite detoxification of the Ironclad tails were also examined. Golder calibrates the hypochlorite feed to the conveyor each morning at the start of operations at the Ironclad facility. A further check on detoxification is made by correlating the contractor's (Ames) estimate of Ironclad material screened, with the amount of hypochlorite applied, during a given shift. It began raining at the site in the mid afternoon, and geomembrane installation had to be suspended for the day. cc: Berhan Keffelew, DMG Carl Hount, DMG Harry Posey, DHG Jim Dill ie, DMG I & E Contact Address ^ CE NAME John Hardaway ^ BL OPERATOR Crip ple Creek & Victor Gold Co. ^ FS STREET P.O. Box 191 ^ HW CITY/STATE/ZIP Victor. CO 80860 ^ HMWMD (CH) ^ SE ^ WQCD (CH) ^ OTHER