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9. SIISFACS AND G$OIINDWATg$ HYD$OLOGY The Division still has several concerns regarding protection of surface and groundwater quality which must be adequately addressed before the application can be approved. Essential baseline groundwater geochemistry and appropriate geochemical analysis of waste rock and tailings material still have not been submitted to the Division for review. The following comments are taken from the hydrology review provided by Tom Schreiner of our Denver Office and forwarded to DGMC in memo form via fax on 11/28/94: a. A minimum of three (3) baseline surface water samples from Little Deadwood Gulch need to be collected and sent to a qualified laboratory for analysis. The lab should be familiar with Colorado surface water standards and reporting procedures. The results provided by DGMC thus far (sample nos. 94060901, 94060902, & 94060903) are inadequate because the detection limits presented are too high, there is no measurement of hardness, and the metals values are not reported in micrograms/liter. The Division also recommends that surface water in Little Deadwood Gulch be monitored at least quarterly during mining & reclamation in order to verify protection of surface water quality. b. A minimum of three (3) representative baseline groundwater samples need to be collected and sent to a qualified laboratory for analysis. No groundwater results have been provided thus far. This requirement is critical in order to determine ambient groundwater quality which may serve as the clean-up standard for spent ore leachate. If groundwater in the vicinity has already been classified by the Water Quality Control Commission, then appropriate standards defined by the WQCC will be used. The Division will also apply a cleanup standard of 0.2 mg/1 WAD cyanide for all detoxified process water and spent ore leachate. There should be at least one (1) representative groundwater sample collected each year to evaluate potential changes in groundwater quality. c. The ore analysis provided is not acceptable as it does not accurately simulate the conditions under which the ore will be processed and reclaimed. The operator will need to have representative samples of each ore body to be mined sent to a reputable laboratory and analyzed for metals leachability using a standard method, such as the Nevada/New York Water Mobility procedure. It will also be necessary to have the operator estimate the anticipated volumes of each ore type to be mined. Existing acid/base accounting results are valuable; 9