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O (Page 2) MINE ID / OR PROSPECTING ID / N-80-266 INSPECTION DATE 11-10-94 INSPECT'OR'S INITIALS CBM OBSERVATIONS This inspection concentrated on leach pad construction activities. when the inspection started, soil liner compaction was taking place just west of geomembrane panel 159. The environmental staff of the mine were picking oversize rocks out of newly placed soil liner material. Heavy equipment was working on the ridge north of Arequa Gulch to remove material and bring it down to proper grade. Hot wedge welding of the panel 154/199 seam was observed. This was a 'tie in' seam where newly placed geomembrane was being welded to geomembrane that had been in place for a few days. The geomembrane was especially dirty but not wet. At times, two liner laborers were necessary to prepare the material by brushing off dirt prior to welding. The joining of the pregnant solution pond area to the upper liner along the south aide of the pregnant pond was observed. The geomembrane pieces moat be extrusion welded and then vacuum tested. No problems were observed in this procedure. The edge of. panel 184 was inspected. Where runoff has flowed down the soil liner in this area some erosion damage was observed. Panel 184 material was rolled back later in the day and the erosion damage repaired prior to deploying more geomembrane. Ridges and rough edges of loader tracks were observed while panel 203 was being deployed. Rebound cracking of the soil liner material was also noted in this area. A Colder Q1~/QC person was notified of the situation and the geomembrane was removed and the soil liner recaopacted until almost no rebound cracks were observed. Two additional density and moisture taste of the soil liner material were performed prior to reapplication of the geomembrane. The soil liner material was found to be within specifications. The panel was then redeployed manually. The inspection was resumed at 1845 hours eo drainage layer deployment could be observed. The drainage layer material was being deployed in a 5 foot lift to construct an access road for haul trucks down the north aide of the pad to the pregnant pond area. On sections of the liner where elopes were steeper than 3H:1V the dozer was required to slow its pushing rate eo 'mass movement' of the drainage layer material would not occur. Most of the time the dozer was operating slowly enough. Occasionally, the dozer operator had to be warned to slow down. At approximately 2300 hours at least three 35 ton truckloads of material that contained a more than usual amount of oversize material were delivered to the area. It became very hard for the Amee laborers to keep up with sorting out the oversize material and, eventually, the dozer operator was instructed by the Golder representative to atop. Unfortunately, this did not occur until this inspector saw many pieces of oversize material being overridden by other material. The contractor was required to excavate a section of drainage layer material approximately 12 feet long by 2 feet wide by 5 feet deep. Excavation to within one foot of the geomembrane was accomplished by tracked backhce. Excavation down to the liner was done by hand. Many pieces of oversize rock were found and removed. Spreading of the drainage layer was halted for approximately 1.5 hours while the buried oversize material was removed. The Ames and Bateman representatives had some ideas for controlling this situation in the future. Source control of the material will be done by making sure that much oversize material will be avoided by pushing a stockpile of material off the top of the pad two area during daylight. The loader operator on pad two will be instructed ae to where to obtain I 6 E Contact Address NAME Mr. John Hardaway OPERATOR CC & V Gold Mining Co. STREET P.O. Box 191 CITY/STATE/ZIP Victor, CO 80860 cc: Berhan Keffelew, DHG ^ CE ^ BL ^ FS ^ HW ^ HMWMD (CH) ^ SH ^ WQCD (CH) ^ OTHER