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subsequently becomes available for water quality standards based on table values, these water <br /> quality standards should be reviewed for compatibility with ambient conditions. The water <br /> quality standards for cadmium and zinc are x+ s values based on Amax data for the twelve <br /> month period of record of July, 1981 through June, 1982. This data is in terms of total metals. <br /> However, all data had suspended solids of less than 30 milligrams per liter. The November 12, <br /> 1981 samples for zinc, iron and manganese were determined to be outliers. The monitoring <br /> location for Segment 13 was on Coal Creek 30 meters upstream from its confluence with the <br /> Slate River and the water quality standards are specific to this location. <br /> 7. Pagegment 14 <br /> An aquatic life classification has not been assigned to this segment because the presence of <br /> aquatic life is extremely limited, flow is intermittent, gradient is steep, and fish habitat is not <br /> present. The potential economic impact of standards to protect an aquatic life classification is <br /> therefore not justified. <br /> 8. Pagegment 15 <br /> Water Supply and agriculture are existing uses. An aquatic life, class 1 classification may <br /> require occasional ammonia removal. The City of Gunnison supported aquatic life, class I <br /> classification. <br /> 9. Page 4, Segment 17 <br /> The Division's initial proposal for water quality standards for segment 17 was based on table <br /> values from 0-100 hardness/alkalinity column. The standards adopted are the same with the <br /> exception of zinc which represents the x+ s of the Amax data for the period of record. The <br /> Amax data was in terms of total metals. However, all data used had total suspended solids of <br /> less than 30 milligrams per liter. <br /> 10. Pagegments 21(a) 21(b) and 22 <br /> Indian Creek has been resegmented into 2 segments, 21(a) and 21(b),to reflect variability's in <br /> water quality and aquatic life. <br /> The uranium standard of 2.0 mg/I for Segment 21(a) is sufficient to protect the aquat65ic life in <br /> that segment. The standard is consistent with historic instream conditions and the existing <br /> discharge at SW33. The determination that this standard is sufficient to protect aquatic life is <br /> based upon bioassay and benthic studies which are included in the record (Homestake additional <br /> Exhibit A, Vol. I1, pp. 232-235 and Homestake Exhibits H-N). This standard will adequately <br /> protect the classified uses assigned in Segment 21(b), and in Segment 22, Lower Marshall Creek. <br /> The uranium standard of.3 mg/I for Segment 21(b) is sufficient to protect the aquatic life in that <br /> segment. The more stringent standard adopted here is consistent with historic instream <br /> conditions based upon data taken at both monitoring stations within the segment, namely SW3 <br /> and WQCD 149. The Division, in implementing and enforcing the standard for Segment 21(b), <br /> should recognize this fact that the standard reflects data from both stations. SW3 is located on <br /> Indian Creek approximately 660 feet below the confluence of Indian Creek and Bull Creek, and <br /> Station 149 is located in close proximity to Homestake sampling station SW4. The standard for <br /> segment 21(b) will adequately protect the classified uses assigned in segment 22, including the <br /> water supply use that exists there. It should be noted that there is not water supply use in either <br /> segment 21(a) or segment 21(b). <br /> 11. Page_6, Segments 29, 30, 31, and 33 <br /> A U.S. Forest Service letter dated December 9, 1981, provided water quality data for streams on <br /> segments 29, 30, 31, and 33 of the Upper Gunnison. It was considered unreliable because the <br /> 17 <br />