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' ~ - ~ • ( Page 2 ) • MINE ID / OR PROSPECTING ID 0 M-83-141 INSPECTION DATE 6 7 95 INSPECTOR'S INITIALS ACS OBSERVATIONS On May 30, 1995 the Division received a telephone report that the Gold Hill Mill tailing pond had been filled by runoff and was about to overtop. Tim Hartley, Acting Mill Manager, was immediately contacted and Mr. Hartley stated that he would immediately assess the situation and report back to the Division. On May 31, 1995 Mr. Hartley reported that the pond was being drawn down through the decant system, that the water level behind the Hazel-A bulkhead was only 2.5 to 3 feet leaving plenty of bulkhead freeboard, and that there was a 2 man crew at the mill monitoring the decanting of the pond water. During the Division's inspection it was observed that there was no water in the pond. The decant riser at the southwest end of the pond (closest to the mill building) ie below the level of the tailing surface. It appears likely that at least some tailing would have flowed into this riser along with the pond water. The decant water line from the tailing pond to the Hazel-A ad it was inspected. There was a small amount of what appears to be tailing material on the ground next to a clean out valve located in the line. The Hazel-A ad it and bulkhead were inspected. There was approximately 1.5 feet freeboard behind the bulkhead. The sill behind the bulkhead appeared gray in color indicating that there may be a deposit of tailing. The bulkhead was leaking in several locations, primarily between the edge of the bulkhead and the rib. A water sample of the leakage was collected and preserved. The leak sampled filled a 1-liter bottle in just a few seconds, and this was just one of several leaks. Water quality analysis of the sample will be provided to the operator and other interested parties when it becomes available. From observations made during this inspection, it is concluded that a lack of available storage capacity in the pond, and a lack of available storage capacity in the Hazel-A ad it, ae well ae the fact that the Hazel-A bulkhead is leaking, has resulted in a discharge of tailing pond water down Caeh Gulch. Cash Gulch ie tributary to Gold Run which in turn ie tributary to Four Mile Creek. The volume of tailing pond water discharged down Caeh Gulch is estimated to be 10,000 cu. ft. This is based on a survey of the storage capacity of the pond that the Division completed in February of 1995 (as described in 2/28/95 inspection report). In its current configuration, the cold Hill Mill tailing pond and decant system cannot be operated ae a zero discharge facility. The operator mu et provide the Division with a viable water management plan, the implementation of which will prevent any future unpermitted discharges. As a stop-gap measure, the valve in the decant line was closed to prevent any additional pond water from flowing to the Hazel-A adit. The proposed borrow source behind (northwest) the existing tailing impoundment was inspected. It was agreed that the operator would dig test pits to demonstrate the depth to bedrock, and estimate the volume of available borrow. It was agreed that the storm water retention berm on top of the dam crest would be constructed from this borrow area, and not from mine waste. It was agreed that construction of the storm water berm would be completed the week of June 19, 1995. All topsoil must be segregated to the aide of the borrow area for re-spreading and reclamation once the job ie complete. It was agreed that the diversion ditches would be cleaned-out concurrently with the storm water berm construction. Problems identified during this inspection, along with specified corrective actions and correction dates, are listed on the last page of this report. COM, Inc. should be aware that the Division will not approve the new Gold Hill Mill application (File No. M-94-117) until a viable water management plan ie reviewed and approved. Also, the operator ie reminded that all flaws in the liner must be repaired by July 1, 1995.