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West Elk Mrne <br />I~ MCC's stratigraphic cross-sections from boreholes in the permit area (Figure SE and Figure SF) <br />confirm this fmding. Again, "aquifer" is a term which should not be used in this context. <br />6. "Information obtained from drilling experience in the mine, and the presence of springs and <br />seeps in the region, indicate that the only potential (emphasis added) regional bedrock aquifer <br />in the general azea is the laterally continuous Rollins Sandstone. The laterally discontinuous <br />lenticular sandstones within the upper Mesaverde Formation support only localized <br />groundwater flows and aze considered to be insignificant in ~erms of the overall hydrologic <br />balance." (p. 8). <br />WWE emphasizes that this statement appears in neazly all of the documents/reports/permit <br />language from the West Elk Mine, and is consistent with the long-term understanding of Messrs. <br />Rold and Dunrud. The only potential the Rollins Sandstone has as an aquifer is that it is a <br />sandstone unit, and as such, would be thought to contain water, but due to the depositional <br />immaturity of the Rollins Sandstone, it actually acts as a water barrier. Furthermore, the Rollins <br />Sandstone is not an aquifer at the mine or in the vicinity, as discussed eazlier in Section 2.05.6. <br />"Should water from different sources mix as a result of subsidence fracturing, modifications in <br />groundwater chemistry could be observed. No significant changes in water chemistry aze <br />predicted, however, due to the small volumes of groundwater present in the Mesaverde <br />Formation and the similarity in chemistry of individual aquifers." (p. 20). <br />I. WWE has evaluated probable water quality changes in some detail and has reached the same <br />conclusion. The groundwater quality data collected by MCC in 1996 and 1997, continue to support <br />this statement. <br />8. "Water often enters the mine in a newly opened area by de-watering the coal seam, adjacent <br />roof or floor. These sources of mine inflow usually dry up within one to two weeks. These <br />strata store and transmit very little water and aze not considered to be aquifers. Therefore, the <br />impacts of de-watering the coals and the strata immediately above and below the coals within <br />the Mesaverde Formation will have an insignificant impact on the hydrologic balance." (p. 20). <br />B-Seam longwall experience indicates that some inflows continue past "one to two weeks," but <br />these inflows generally drop to levels of less than 10 gpm, except; as noted from the fault system <br />inflows. ' <br />9. CDMG staff quantified the maximum mining impact on the North Fork and the probable <br />mining impact on the North Fork for total dissolved solids (TDS), using conservative <br />assumptions. Conclusions from this analysis contained with the CHIA aze as follows: <br />• "The assessment indicates that no significant impacts will occur on the North Fork at <br />the maximum extent of mining and no water uses will be precluded." <br />• "No significant impacts to the system aze anticipated and no water uses will be <br />precluded on the North Fork of the Gunnisom m the probable development <br />~, scenario." (p. 26) <br />2.05-146 November 1004 PRII <br />