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J. E. STOVER & ASSOCIATES, INC. P.O. Boz 60340 GRAND JUNCTION, COLORADO 81506 PHONE: (970) 245.4101, FAX 242-7908 MINE ENGINEERING MINE RECLAMATION June 8, 2006 Dan Mathews Division of Minerals and Geology 101 South 3rd Suite 301 Grand Junction, CO 81501 Re: McClane and Munger Canyon Mines Permits C-1980-004 (McClane) and C-1981-020 (Munger) 2005 Water Year Annual Hydrology Report CIVIL ENGINEERING CONST. MANAGEMENT ~~v~i~~0 SUN ~ X1006 dM~~1°e~d Gp0~o9Y v~jD" Dear Mr. Mathews: - -' ~ ` " The DMG's preliminary adequacy review letter dated April 21, 2006 requested additional information. On behalf of CAM MINING LLC, the following discussion and amended data are provided: CAM - A goal of this adequacy response is to propose the best baseline data available for the Ground Water Monitoring Wells and to integrate it into the permit and upcoming AHR's. In the groundwater section of AHR's for 1986, 1987, 1988, 1989, 1990, 1991 and 1992, it states baseline data from 1986 was used. However, when you review Table 5 from the same AHR's, S W L baseline year 1981 was used. Then, in water year 1993 in the groundwater section, the text changes and it says baseline data from 1981 with no reference to 1986 baseline data, The next AHR the operator could locate was for water year 1996 and in the groundwater section it states SWL baseline data for 1981 and 1986 are used. The 1985 and 1986 (1986 WY) data were collected in response to Stipulation 4 of the Central Facilities Revision for wells GW-2 through GW-8. Stipulation No. 4 apparently asked for an additional year of baseline data. The operated has summarized the 1981 and 1986 WY data which for future reports will be used as baseline. Baseline data for GW-1 will be obtained from 1983 and 1984 monitoring. The baseline data are presented on new Table 4.4i. There was no activity or discharge during the1985-986 water-year, so the EC values should berepresentative ofpre-mining conditions. Well GW-1 has not been affected by mining so the 1983 1984 monitoring data should be acceptable for baseline conditions. 1. On page 5 of the AHR, CDPS Discharge Monitoring Reports are mentioned. Please amend the narrative to include a brief summary addressing the occurrence and nature of any CDPS effluent criteria exceedances during the water year, for any_of the discharge points. CAM -Added summary addressing the occurrence and nature of effuent criteria exceedance at the McClane Canyon Mine in August 2005. Please see updated pages 5 and 6. 2. DMG -Due to installation of Culvert P, mine water now enters East Salt Creek downstream from SW-1. Coordination of SW-1 sampling concurrent with mine discharge events would provide useful information, and should be conducted as practicable. DMG -With regard to groundwater, we recommend that the discussion in the AHR be expanded and the permit document(s) may need to be clarified or supplemented with additional information. The approved monitoring program for McClane includes wells GW-1 and GW-3. The monftoring program for Munger includes wells GW-1, GW-3, and GW-6. The current approved programs include quarterly monitoring for freld parameters only (temperature, pN, specifrc conductance, and static water level). Six alluvial wells were drilled and samples were collected forlaboratory analysis during the period December 1977 through April 1979. Since the time of baseline data collection, apparently no samples have been collected for laboratory analysis. Field parameters only are measured for the wells in the current monitoring program. We have the following specific comments regarding the presentation and analysis of groundwater data.