REP40291 - Laserfiche WebLink

Home Browse Search

Movnlain Coal Company 1998 Annual Hydrology Report West Elk Mine NE Panels Sealed Sump • As described in the Probable Hydrologic Consequences (PHC) of MCC's permit, an additional underground sump has been proposed in the area of the now mined out 10 and 11 Northeast panels. Mining of Panel 11 was completed in July 1998. This sump will hold water to be pumped out to the Sylvester Gulch pumping facility, which was approved in Technical Revision No. 83. A treatment facility was also proposed to be constructed in conjunction with the pumping facility, but given the good quality water being dischazged from the NW Panels sealed sump into Lone Pine Gulch, MCC believes that water from the NE Panels sealed sump will be as good of quality. The NE Panels sealed sump and the Sylvester Gulch pumping facility is expected to be on-line during WY99. As the majority of MCC's futwe mining will be to the south and east of the existing portals, MCC will soon utilize the NE Panels sealed sump as the primary sump. MCC still intends to hydraulically connect this sump with the NW Panels sealed sump with the NW Sump #1 Horizontal Drill Hole, as discussed in the PHC. Samples of Mine Water Inflows Minor Revision No. 208, approved by the Division on January 21, 1998, added the requirement to collect mine water samples and report the results in the Annual Hydrology Reports. Results of the samples collected during WY 1998 aze included in Appendix H of this report. All locations where a mine water sample was collected aze shown on Map 1. • MCC collected numerous samples in the vicinity of the Lone Pine seals to ascertain the water quality of the water to be pumped out of the NW Panels sealed sump. In addition, MCC collected water quality samples from the pipeline during discharge in compliance with MCC's CDPS permit. MCC also collected water quality samples from the NW Sump Horizontal Drill Hole (NW Sump HDH #1), which is the drill hole that will hydraulically connect the NW Panels sealed sump to the NE Panels sealed sump. The water from this horizontal hole is considered to be the "bottom" of the sump. MCC also collected samples from development mining azeas in the B South Mains and the 14 Tailgate. Water quality samples were collected from a horizontal hole, identified as 14SEHG HDH #3 on Map 1 that was drilled through the 14SEHG fault. This hole was drilled to determine the extent of the 14SEHG fault, and to discover more information about this fault. Water quality samples were also collected, from the 14 Tailgate, entry #1, cross-cut 15, which is also along the 14SEHG fault. Mine Water Balance Figwe 6 shows the mine water balance components for WY98. Inflows from the 14 SEHG fault and the B East Mains fault continued to have a significant impact on the mine water balance. North Fork diversions of 372 acre-feet were nearly identical to WY97, which is reasonable considering that mine production was about the same. The total volume of water entering the mine from pond FW-1, inflows from the 14SEHG fault and the B East Mains fault, and other . minor inflows was approximately 827 acre-feet. 3 - 1.500 age 2 Wrig t Water Engineers