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L tnrraductinn On January 30, 198b, the Colorado Division of Minerals and Geology (CDMG) approved a Technical Revision to reduce the hydrologic monitoring program at the site. Stations associated with the Revision Area No. 2 in Deep Creek (DC-1, W-17 and W-18) were not required to 6e monitored by the current program; the water quality parameters of arsenic, cadmium, lead, mercury, molybdenum and selenium were eliminated from all stations except well W-161ocated in the reclaimed area of the east pit; water quality sampling of the Stolisteimer Creek alluvium was added to station A-1 and eliminated from station W-1; and frequency of sampling, depth-to-water measurements, and stream discharge measurements were not changed by this revision. In June 1988, the CDMG approved a techtical revision to conduct this monitoring program on a quarterly basis and in May 1990, a technical revision was approved which eliminated all groundwater monitoring at the site and all monitoring wells were reclaimed. In January 1992, the CDMG approved a reduction in surface water sampling to quarterly flow measurements and semiannual water quality at three surface stations. Tn early 1993, a decision was made to resume alluvial aquifer monitoring and in late summer, wells A-1, W-1 and W-S were reinstalled for the purposes of this monitoring. Groundwater in bedrock aquifers were not resumed because [he analysis of the probable hydrologic consequences of mining impacts indicated that no further potential impacts would occur. The following sections of this report describe the methods and results of the hydrologic monitoring program conducted at the Chimney Rock Mine site during 1996. Also contained in this report is e comparison of the data collected over the 1985 through 1946 period and recommendations for future monitoring.