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5. The DOSd representative observed numerous dead brown trout in the <br />Purgatoire River from a point dotirnstream of the Ciruela Canyon confluence. On <br />March F, 1988, the DOW representative counted 348 dead fish in the river below <br />the discharge. Dead fish were observed for a distance of approximately 3 <br />miles downstream. <br />6. On March 7, 1988, the DOW representative returned to the vicinity <br />of the mine. The representative observed the river upstream of the confluence <br />with Ciruela Canyon and found one dead trout. This trout appeared to have <br />been dead for a longer period of time than the trout which were examined below <br />the confluence, based on observations of the eyes of the fish. No other dead <br />fish were observed upstream of the confluence on March 7, 1988. <br />7. Aquatic biomonitorin <br />e sample <br />eitluent <br />upstream sample tlitl not exhioit toxicity in the oiomonitoring tes[s. i~er <br />Division policy, effluent is considered to be "acutely toxic" if it is lethal <br />to greater than 50% of the test organisms. <br />8. On March 7, 1988, a representative of tl~e Division inspected the <br />site and observed dead fish in the Purgatoire River below the Ciruela Canyon <br />confluence and observed no dead fish in the river above the confluence. <br />9. On Marrh 1~ 1~~ , the <br />the site and o sserved that fish wereved that fish were <br />Ciruela Canyon confluence. The~re~r <br />point 002, and in the river, ob th up <br />10. <br />ty. <br />acutel <br />Division representative again inspected <br />still dying in the river below the <br />ese~rar;ve collected samples at dischar <br />e run on <br />ci The upstream sample showed no <br />11. In an effort to control the levels of suspended solids in the <br />minewater discharge, the company began adding flocculants to the wastewater, <br />beginning early in 1988, to aid in settling out of the suspended material <br />prior to discharge. At least one of the flocculants used by the company is <br />toxic to trout at certain concentrations. P1ore specifically, the flocculant <br />Nalco 8852 is lethal to 50% of trout in 96 hours at a concentration of 0.47 <br />parts per million. <br />' 12. The Purgatoire River and Ciruela Canyon are "state waters" as <br />defined by 25-8-103(19), C.R.S. (1982). <br />~~, r <br />4~ <br />u~Z <br />-2- <br />