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A. Maintenance of a High Temperature at the Seep. <br />Since the seep was first monitored, temperature has fluctuated very little. Division records <br />indicate variations on the order of tenths of a degree to a few degrees since November 1997. <br />Thus, because the temperature has remained relatively constant, and high, there must be a <br />constant supply of heat to the seep water source. If the fault waters reach the seep via seepage <br />through the coal wall, down-dip of the sump, then the sump water itself must be the source of the <br />thermal mass. Without a heat source at that point, the seep water could not have maintained the <br />measured high temperatures. West Elk Mines maintains that the seep water heat comes from <br />thermal waters beneath or close to the seep. An alternative simple explanation seems possible. <br />When warm fault waters (at least 85 to 95° F, and possibly higher) were encountered, they <br />were conveyed to the NW Panels sealed sump. As the sump eventually filled, water was <br />discharged to the North Fork Gunnison River via the Lone Pine Gulch pipeline. Because warm <br />incoming water is eventually dischazged via the Lone Pine Gulch pipeline, a relatively high <br />temperature has been maintained in the sump. Thus, a relatively constant, high temperature <br />could have been maintained in the seep. <br />B. Major Element Chemistry and pH. <br />Because the geochemical composition of the fault waters do not match that of the seep, West <br />Elk Mine maintains that this is evidence that the two waters come from different sources, through <br />different fractures. Waters in the Rollins Sandstone aze tazgeted as a possible source. However, <br />the Rollins Sandstone water is likewise of a composition different from the seep. While this does <br />not dismiss the Rollins as the source of the seep water, or at least a component of the seep, it <br />does require an explanation of how the Rollins water evolved from its composition to that of the <br />seep water. That path is at least as complicated as a path from the fault waters to the seep water. <br />A feasible model for evolution of the seep water from the fault water via interaction with certain <br />minerals and meteoric water can be developed. <br />Snow and rain infiltrate rocks tip gradient of the NW Panels sealed sump. As these waters <br />travel through the rock mass, soluble constituents enter the water. As these meteoric waters <br />containing dissolved solids mix with the fault waters in the sump, the sump water changes in <br />composition. <br />The addition of Ca and Mg might be explained by the dissolution of dolomite, (CaMg)C03 <br />or some combination of minerals such as K-feldspar, gypsum and/or clay. The presence of <br />bicarbonate in the waters argue for a carbonate source, although the other mineral sources cannot <br />be excluded. If dolomite was dissolved, the incoming fluid containing it should also contain an <br />equivalent (more-or-less) amount of bicarbonate. The seep water contains a lower amount of <br />bicarbonate than the fault, but more than enough to balance the Ca and Mg from dolomite <br />dissolution. Therefore, it is feasible that the incoming meteoric water contained Ca, Mg and <br />bicarbonate, but the bicarbonate was lower in that fluid than the fault waters, so the net effect <br />was to lower bicarbonate in the mixture. <br />6 <br />