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` ~~ • (Page 2) • ' MINE ID # OR PROSPECTING ID #M-80-244 INSPECTION DATE 10-13-99 INSPECTOR'S INITIALS BK_ OBSERVATIONS The Division conducted a monitoring inspection of the site in response to the operators's report of a Cyanide Spill that occurred outside of the protected area on 10-12-99. On 10-12- 99, late in the afternoon, CC&V contacted the Division to inform the fact that a cyanide spill had taken place outside of the protected area and that the operator had implemented all the necessary emergency response plan for such spill as approved in the Emergency Spill prevention plan for the site. The phone message also stated that none of the spill reached the waters of the United States. On 10-13-99, the Division's representative arrived on site at 7:OOam and proceeded to the spill area. Present during the inspection was, Mr. Scott Lewis of CC&V, the Manger of Environmental Affairs. Mr. Lewis explained how the spill occurred. It appeared, a weld in one of the 24" header pipe ruptured along the south side of the toe dam and allowed the spill to occur. Again, according to Mr. Lewis, APPROX. 1271 gallons of solution containing a total of .96 lbs of Sodium Cyanide or 0.51 lbs of cyanide was released outside of the protected area. Since the existing solution application system has in place a sensor that detects changes in both pressure and flow with in 11 seconds, the computer shut off the pumps. The print out from the computer shut off system was provided showing what was reported by Mr. Lewis. The solution that existed with in the Header Pipe prior to rupture & shut off time was what was released on to the unprotected areas. All the contaminated soli was removed and placed on to the leach pad or protected areas. The area where contamination occurred after removal of the contaminated soil was treated with Calcium hypochlorite to make sure, all the residual cyanide was detoxified. According to Mr. Lewis, all the clean up was completed by 10:30am on 10-12-99. water sampling in Arequa gulch was initiated immediately. Samples from AG 1.5 NPDES COMPLIANCE POINT OOlA AND GROUND WATER monitoring points 3A-36 AND 3B-63 were collected and the operator plans to collect samples on a daily basis to make sure no contaminants reached the waters of the United States. Results are requested to be expedited and should be reported to the Division as soon as available. The Division also collected a sample from AG 1.5 AND SAMPLE WAS DELIVERED TO THE CDOH&E LAB THE SAME DAY and requested an expedited result. Operator was offered a split but declined and collected its own sample. Inspected the low volume and high volume solution collection system area for phase II had recorded the following readings. LOW VOLUME PUMP #1 READ .43 FEET OF HEAD LOW VOLUME PUMP #2 READ .26 FEET OF HEAD HIGH VOLUME PUMP #4 READ 24.9 FEET OF HEAD HIGH VOLUME PUMP #5 READ 27.0 FEET OF HEAD HIGH VOLUME PUMP #6 READ 31.2 FEET OF HEAD Inspected the Phase II& III expansion areas, work was continuing in both areas. Clay liner was being deployed and being compacted along the West facing slopes of the Phase II expansion areas.Drain cover was being placed along the North facing slopes of the Phase II expansion areas. In the upper area of the Phase ii leach pad area where the valley of the leach pad and under drain were located which was completed in 1996, the operator had removed the ore, drain cover fill and geomembrane liner to determine why the AREA WAS CONTRIBUTING A LOT OF WATER TO THE LEAK DETECTION SYSTEM. According to Mr. Lewis, after the liner was removed, all they found was a very wet spot but clay liner was measured to be 14" in thickness. He stated that the clay liner was dried prior to placement of geomambrane. At the time of the inspection, Poly flex the liner installers were finishing up deploying liner and conducting minor repair work. Two Golder QA/ QC personnel were on site making sure the work was being conducted in accordance wit the approved specification. Inspected a small area approx. 150 square feet