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the fault waters have much less. This implies that both have a young atmospheric carbon component. The higher pmc in the sump water implies the sump water has more modern water than the seep water. This implies further that there must be an older water diluting the sump water between the sump and the seep, assuming of course that the sump water is the source of the seep, or that the seep water did not evolve directly from the sump water that was collected. Neither interpretation appears to be favored. The tritium ('H) values for most of the samples, both fault, sump and seep, generally record some component of "post-bomb" water. a few of the fault waters do not. Again, the greater amount of deuterium in the sump requires an expla~ration similar to that provided for the "C values, namely that there is either a second source of "old" water between the sump and the seep, or the sump water is not representative of water that possibly recharges the seep. Overall, the greater abundance of "bomb" water in the sump and seep relative to the fault implies that the faults contain a higher abundance of non- bomb, i.e. old, water. Nonetheless, the presence of any "bomb" water in tl~e faults implies either a relatively young age a mixture of old and young waters. This supports the notion, presented above under the oxygen isotope discussion, that recharge ma}~ be relatively rapid, in this case, possibly less than 50 years. Summary Overall, the geochemical information supports an interpretation that waters from the faults in the West Elk mine, combined with meteoric water which has acquired some dissolved constituents en route to the Northwest panels sump, is leaking across the B- seam dam between the Bear Mine and West Elk Mine underground workings and out the Edwards Portal seep. Dilution of the fault water with meteoric water explains most of the trends in major element composition as well as the shifts in carbon, oxygen, and hydrogen isotope compositions. Younger carbon-14 and tritium ages in the sump and seep can be ascribed to the presence of more modern waters in these areas than the faults. Sulfur isotope shifts require incorporation of sulfate which was probably derived from a source area undergoing sulfate reduction. Gas compositions support the notion that modem water is a component the fault waters. The constant temperature of the seep indicates that, provided the sump water is the source of the seep water, [he sump is being constantly replenished with hot fault waters. There is evidence that the sump waters 7