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When measured against the material damage suspect criteria list, <br />all parameters measured for the surface water sites were within <br />compliance ranges except for two; cadmium and manganese. <br />Cadmium Comments <br />Slightly elevated cadmium levels were observed for both above and <br />below the mine on McClane Creek. Since the raised levels observed <br />were within a .O1 range and exist both in the above mine and below <br />mine waters, it can be assumed that this is due to natural causes, <br />and not the mine. <br />Manganese Comments <br />However, this is not the case with increased Manganese levels <br />observed in all surface water wells, both below and above the <br />McClane Mine. The material damage suspect level for manganese is <br />.2 mg/1 and the following levels were recorded in the third quarter <br />for the wells listed below: <br />SW-1 East Salt Creek above the mine 5.220 mq/1, 26.1 times <br />the recommended level, <br />SW-8 East Salt Creek below the mine 4.660 mg/1, 23.3 times <br />the recommended level. <br />However the data show an actual .56 mg/1 decrease downstream <br />SW-5 McClane Creek above the mine 7.090 mg/1, or 35.45 times <br />the recommended amount, <br />Sw-2 McClane Creek below the mine 6.950 mg/1, or 34.75 times <br />the recommended amount. <br />Again, the numbers decrease below the mine <br />Clearly, there exists a potential problem with manganese in the <br />McClane Canyon area. Comparison with the Munger Mine proves this <br />to be true. <br />SW-3 Munger Creek below the mine 0.831 mg/1 in the 1st <br />quarter. This makes sense since the area is devoid of surface <br />water except in storm events, with two out of four quarters <br />dry. <br />From the above data, it can be assumed that this phenomena is <br />localized in the McClane Canyon. Since the manganese levels <br />decrease the further downstream one goes, it can be ascertained <br />that the high levels observed do not originate with the mining <br />operation. <br />More extensive review of manganese levels from 1988 to 1992, <br />indicate. that this is a recent phenomena, with levels rising since <br />1991. Therefore, two solutions present themselves: one, a geologic <br />rationale, and two, a human error factor may be present. <br />A review of the geologic rock types suggest that perhaps this <br />manganese may be originating in the Mancos shale outcrops, known to <br />be high in certain metals. A Mancos shale outcrop can be found to <br />the north of the permit area. Evidence of recent weathering of a <br />