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~~ V Tom Augustine, Senior Mining Engineer for WFC had heard rumors that dead fish had been observed on Saturday, March 5, 1988 in the Purgatoire River. Further, Division of Wildlife (DOW) personnel had been seen in and around the Purgatoire River over the weekend of March 5, 1988. Consequently, I telephoned Bob Holder, District Wildlife Biologist for the Division of Wildlife in the Trinidad area, the morning of March 8, 1988. In response to my inquiry, he reported that the Division of Wildlife had counted 517 dead fish, mostly Brown Trout of various size ranges below Ciruela Canyon. I told Mr. Holder that I had sampled the previous week and hadn't noted any problems at WFC sampling station PRS-3, which is downstream of Ciruela Canyon. Because the fish loss was downstream from the Golden Eagle Mine discharge at Ciruela Canyon, WFC immediately undertook a sampling program to identify the potential cause of the fish loss. The sampling program results are included in the response to item 6 above. Since WFC is very familiar with the water quality of the mine discharge, and the only chemical treatment which WFC utilizes is the flocculant for settling suspended solids, we suspected that it might have been the flocculant which caused the fish mortality. Therefore, WFC stopped using NALCO 8852 immediately after learning of the fish loss on March 8, 1988, and after unsuccessful trials with NALCO 8873, discontinued all flocculant use on March 11, 1988. On March 10, 1988 WFC notified the Division of Wildlife, Colorado Department of Health and Colorado Mined Land Reclamation Division by letter and by phone that the fish mortality might have resulted from an overdose of the NALCO 8652 flocculant. On March 9 and 10, WFC continued investigations including sampling from the western boundary of the New Elk Mine approximately five miles upstream from the fish loss to approximately four miles downstream from the Ciruela Canyon discharge. Sampling was completed by March 10, 1986 and samples were submitted to a commercial laboratory for analyses. WFC continued to make a diligent effort to identify the source of the problem by working with government agencies, laboratories and the product supplier. Our opinions as to the probable cause of the fish mortality were addressed in the April 22, 1988 meeting. At this time WFC reported that an operational error had occurred resulting in an overdose of the NALCO 8852 flocculant.