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• (Page 3) • NINE ID / OR PROSPECTING ID / ~ K-80-446 INSPECTION DATE 10/21/94 - 10/24/94 INSPECTOR'S INITIALS GSC When temperatures rise, water in the cover drain fill on the upper southeastern elopes of the pregnant pond rune downslope and into the pregnant pond anchor trench. This occurs at various intervals downelope from the cover material. Most of these areas are completely covered with VLDPE liner, however, in two places the soil liner was exposed and some erosion had occurred. John Hardaway explained that water is pumped from the trench within 24 hours of accumulation pursuant to a Division requirement. He also stated that the entire area exposed above the anchor trench will be examined and tested for moisture and density after all geotextile ie installed on the pregnant pond and before the area ie overlapped. Gundel Lining Syeteme personnel were observed installing 300 foot long panels along the eastern aide of the toe berm. Oversize rocks had been removed from the clay liner before the VLDPE was applied. A portion of the western half of the toe berm was inspected and no oversize rocks or angular fragments were observed. Liner installers and q)1/QC personnel were observed looking for and marking defects and oversize protrusions, completing fusion welds along the panel seams, extrusion welds on patches, performing pressure taste on seam welds and vacuum taste on patches. Pete Bowers of Golder explained how seam welds are tested. An attempt is first made to pressurize the entire seam. If this ie not possible, the seam ie tested in segments until a positive teat ie completed over the entire seam and the defective seam welds, if any, are removed. Pete also showed where the temperature is monitored on site where seam welding is being conducted. An inspection of the northeastern elope of the pad revealed there are at least two significant folds in the VLDPE liner. This was pointed out to Pete Bowers who said that he has not yet cleared the area. The topsoil stockpiles east of the heap leach pad and near the processing plant area were inspected. The downelope areas are lined with anchored hay balsa. Topsoil material is resting on top of the bales near a dry drainage which begins just below the topsoil stockpile. This has been mitigated by anchoring two lines of bales in the drainage within 50 feet of the stockpile perimeter and three additional lines at approximate 100 foot intervals further below. The eastern and western portions of the topsoil stockpile have been graded to 3:1 approximately and the central portion adjacent to the existing access and haul road ie at repose. The operator brought to the Division's attention that portions of the soil liner exposed when the pregnant pond anchor trench was excavated are below the minimum 12" spec. Both aides of the trench are covered by VLDPE liner in moat of the northern and eastern portions of the pad, however, the soil liner thickness was checked in the exposed areas. The liner ranged from 1 to 7.5 inches thick near the southwestern extent of the trench and 4 inches thick in the northeastern elope below the 15 inch solution collection pipe. The exposed areas were limited to the uphill aides of the trench. Dave Dix and John Hardaway explained that the thin areas were filled and compacted prior to installation of the pregnant pond geomembrane and that this would be done on areas upelope from the trench prior to installation of the geomembrane. The Division will consider this under further investigations. The Division observed the placement of drain cover fill on the upper liner on~the evenings of 10/22/94 and 10/23/94. On both nights two dozers (CAT D8 and D9) were pushing the cover material. Two CA/QC personnel were on site with 4 Ames laborers. There were three banks of portable lights in the area. Ae the material was pushed downelope there were certain angles at which the material was shaded. The laborers carry flashlights for when this happens, however, a more satisfactory solution would include more strategic placement of the portable lights. Ted Birdeill explained that the lights are periodically repositioned. Oversize rocks ranged from about 1.5 inches to over 6 inches in size. Many of these were somewhat rounded but some angular fragments were found. The crews did a good job of wrinkle control ae the new material is pushed downslope. This is accomplished by shoveling some fill on the downelope aide of wrinkles developing in the liner, weighing them down and preventing them from doubling over. On the morning of 10/24/94 a deer was discovered in Pond SA. It was removed by operator personnel using rope.