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"bomb" water in the faults implies either a relatively young age or a mixture of old and young <br />waters. This supports the notion, presented above under the oxygen isotope discus35on, that <br />groundwater recharge may be relatively rapid, in this case, possibly less than ~0 years. <br />SUMMARY <br />Overall, the geochemical information supports an interpretation that waters from the faults <br />in the West Elk mine combined with meteoric water which had acquired dissolved constituents <br />en route to the Northwest panels sump, and this water is now leaking across the B-seam dam <br />between the Bear Mine and West Elk Mine and out the Edwards Portal seep. <br />Dilution of the fault water with impure meteoric water can explain trends in major element <br />composition that goes from a sodium bicarbonate water to a dilute, mixed sodium calcium <br />magnesium, sulfate water. The occurrence of sump water on a trajectory between the fault <br />waters and the seep water augment this interpretation. <br />Shifts in carbon, oxygen, and hydrogen isotope compositions also can be explained through <br />simple dilution with local impure meteoric waters. Variations in S"C between the faults and the <br />seep, and between the sump and the seep, do not provide a compelling azgument in favor of a <br />third water source; the same changes can be explained with other simple reactions, of natural <br />vaziability uncertainties. <br />Younger carbon-l4 and tritium ages in the sump and seep can be ascribed to the presence of <br />more modern waters in these azeas than the faults. Local meteoric waters would be modem <br />waters. <br />Sulfur isotope shifts require incorporation of sulfate which was probably derived from a <br />source azea undergoing sulfate reduction. Such shifts are compatible with methane oxidation. <br />which could explain the shift in S''C values as well. <br />Gas compositions support the notion that modern water may be a component of some of the <br />fault waters. Coupled with the fact that the oxygen and hydrogen isotopes fall close to the <br />meteoric water line, and the evidence that there has been only relatively minimal oxygen isotope <br />exchange between the waters and rock oxygen in even the hottest fault samples, argues for <br />somewhat rapid meteoric water rechazge of the fault waters. <br />The constant temperature of the seep indicates that, provided the sump water is the source of <br />the seep water, the sump is being constantly replenished with hot fault waters. If the fault waters <br />cease being dischazged to the sump, or if they are stored elsewhere, the seep waters, if derived <br />from the sump, should cool. Otherwise, this would azgue for a separate source. <br />There is evidence that the sump waters which were sampled may not be representative of <br />that in the entire sump, and so may differ from that which could be seeping across the B-seam <br />dam. A tracer study could clarify this question, decisively. <br />Missing and confusing data notwithstanding, there appears to be ample geochemical support for <br />the interpretation that the fault waters, once discharged to the Northwest Panels sump, are <br />combining with meteoric water and leaking across the B-seam barrier and out the seep. <br />The above description does not require a separate water source, requires no reverse ion <br />exchange to explain any of the data, and uses focally available water and minerals -- materials <br />10 <br />