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Monisorinp Results Surface water chemistry was observed to be stable over the eleven year monitoring period (Table 1 and Appendix n. The water may be classified as a mixed calcium/magnesium-sul- fate/bicarbonate type water. The degree of ionization varied with season, being highest during ' low flow and lowest during high flow. The ratio of calcium to magnesium was generally consistent over the~seasons; however, there is a shift in the ratio of sulfate to bicarbonate, with ' bicarbonate being more prevalent during high flow conditions. These ionic conditions also influenced the conductivity and TDS as exhibited in the graphs in Appendix I. ' Analysis of trace metals indicates low concentrations. Aluminum and iron were detected in all samplings, higher values being reported during high flow events (Appendix n. Manganese and zinc were also sampled and found in only trace amounts. ' Mining and reclamation operations at the Chimney Rock Mine appear to have little or no effect on the quantity or quality of area surface waters. This may be due to the mines inactive status during 1985 through 1989. Backfill and grading activities occurred in the Revision 1 Pit and Surface facilities during 1990 and 1991; however, sediment control ponds established o^ the disturbed areas eliminated runoff of surface waters from the mine site. All NPDES forms were ' filed with the Colorado Department of Public Health and Environment during quarterly reporting periods. CDMG also received copies of these reports. Results of the annual pond survey conducted in October aze contained in Appendix III. ' GROUNDWATER ' The three alluvial wells A-1, W-1 and W-5 were replaced and added to the monitoring program in 1993. Water levels were measured during the quarterly samplings with water chemistry being ' analyzed during the second and fourth quarters. All data is contained in Appendix II. Water levels in the three wells varied seasonally. W-1 was dry during the second, third and fourth ' quarters while well W-5 was dry in the third quarter. ' Water quality was analyzed from wells A-1, W-1, and W-5. The water is considered a mixed ion calcium/magnesium-sulfate bicarbonate type. Historically, well A-1 has a higher ion concentration than well W-5 as exhibited by the values of conductivity, TDS, and cation anion analysis. Sodium and magnesium concentrations were also higher in well A-1. No water was analyzed from well W-1 because it was dry for both sampling periods and only a partial water sample could be obtained from well W-5 in December due to the low volume in that well. 1 ' 1995,053/3/0130-96(9~59uv) 6