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<br />STATE OF COLORADO <br />DIVISION OF MINERALS AND GEOLOGY <br />Department of Na[ural Resources <br />1313 Sherman St., Room 215 <br />Denver, Colorado 80203 <br />Phone: (303) 8663567 <br />FAX: (303) 832-8106 <br />DATE: January 31, 2006 <br />TO: Sandy Brown <br />FROM: Dan Mathews <br />RE: 2005 AHR for McClane and Munger Canyon Mines <br />Permit No. C-80-004 (McClane) and C-81-020 (Munger) <br />COLORADO <br />DIVISION O F <br />MIN SRALS <br />GEOLOGY <br />REC LAMATION•MI NING <br />SAFETY•SCIENCE <br />Bill Owens <br />Governor <br />Russell George <br />Ezecmive Director <br />Ronald W. Cattany <br />Division Director <br />Natural Resource Trustee <br />I have conducted a preliminary review of the 2004 AHR for McClane and Munger Canyon Mines. <br />I need to request assistance from a staff hydrologist, to conduct the PHC review. Jim Burnell has <br />conducted the reviews in the past. Monitoring appears to have been conducted in conformance <br />with the approved plan, with the exception of certain apparent discrepancies associated with <br />CDPS permit reporting. Precipitation was significantly higher than average during the water year, <br />and higher than it has been in recent years. East Salt Creek flows were higher and TDS levels <br />lower than in recent years. Operator was able to obtain data from the ephemeral drainages of <br />McClane Creek and Munger Creek during the year, which is not always the case. <br />McClane <br />McClane Creek Temporary Diversion <br />Based on survey information presented in last year's AHR, a technical revision was submitted <br />and approved to install a new culvert "P" at the road crossing on lower McClane Creek, which will <br />re-direct the creek away from the eroded diversion segment that was created when the road was <br />constructed across the channel prior to August 3, 1977. The culvert will reestablish the original <br />flow path of McClane Creek, and will result in flow down McClane Creek entering East Salt Creek <br />downstream of the haul road bridge, rather than upstream of the bridge. <br />Minewater InflowlDischarge <br />Relevant data is included in Table 1, and comparison to PHC projections is provided in the <br />narrative. Of note is the fact that reported inflow of 31.5 gpm is the highest inflow reported since <br />coal production resumed in 2000; it is approximately twice as high as inflow reported for last year, <br />and over 150% of the projected inflow predicted in the PHC in Appendix N of the permit <br />application, when projection assumptions are adjusted for "actual" coal production of 300,000 <br />tons per year rather than "worst case" coal production of 1.7 million tons per year. Historically, <br />reported minewater TDS levels have been lower than average TDS values reported at SW-1, the <br />upstream monitoring site on East Salt Creek. Based on values reported in the 2005 report, <br />minewater discharge TDS was slightly higher than average TDS values at Site SW-1. This <br />appears to be due to the lower stream TDS values associated with elevated stream flows. <br />Ground Water Sampling <br />• Required quarterly monitoring data for Wells GW-1 and GW-3 (water level and field <br />parameters) were provided. <br />• CDPS mine water discharge sampling data were reported in CDPS discharge reports (see <br />Permit System records, not required to be included in AHR). One item of note is that the <br />Office of Office of Colorado <br />Mined Land Reclamation Active and Inactive Mines Geological Survey <br />