2008-11-24_PERMIT FILE - C1996083 (8)

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B-Seam and Strata Above B-Seam Water Quality Analysis, Bowie Coal Mine 6 Conclusions • • The water quality in the strata Above the B-Seam is highly variable across the Permit area and may be due to the heterogeneous nature of the coal-bearing strata (Mesa Verde Formation). • The water quality data indicate that several wells installed in the strata Above the B-Seam may have been compromised by grout contamination. Wells DH58a, DH-67B, TC-03-02 and TC-03- 03 are likely contaminated. • The variable nature of the water quality in the strata Above the B-Seam is likely present throughout and beyond the current Mine Permit boundary area. • The water quality in the B-Seam is reasonably consistent in wells DD-NM4x98-28 and DH-67B. • The water quality in well TC-03-O IB has an extraordinarily high pH, averaging 11.8 s.u. and indicates possible grout contamination. • The water quality in the B-Seam is likely consistent throughout the current Mine Permit boundary area and beyond. • It should be noted that the available water quality data from the wells analyzed in this study are limited to only a few samples; therefore, any detailed statistical analysis of the data or assessment of seasonal trends is not possible. The expected range of water quality values of pH, TDS, Total iron, and Total manganese for the groundwater Above the B-Seam and within the B-Seam in the mine area, presented in Tables 3 and 4, was determined based on available water quality data discounting information from potentially grout contaminated wells. TABLE 3 - EXPECTED RANGE FOR ABOVE B-SEAM WATER QUALITY EXCLUDING SUSPECT CONTAMINATED WELLS H Field H Lab TDS Total Iron Total Mn MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX ABOVE B SEAM ALL 7.6 <10.0 7.26 <10.0 1285 4683 0.05 17.7 <MDL 0.56 SITES TABLE 4 - EXPECTED RANGE FOR B-SEAM WATER QUALITY EXCL UDING SUSPECT CONTAMINATED WELLS H Field H ab TDS Total Iron Total Mn MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX B SEAM 6.5 8.8 7.47 9.37 2186 8131 .011 31.8 <M L = 1-129 ALL SITES September 2008 HydroGeo, Inc. 0