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' Kathy Welt, MCC <br /> July 20, 1998 <br />' Page 3 <br /> During this period, "clean" water was segregated and was pumped to and discharged <br />' from the sedimentation ponds on the surface. <br /> • In January 1997, the second lazge fault system was encountered in the 14SE headgate <br />' (formerly termed the 1 SE headgate). Initial inflows were estimated at 8,000 gpm; and <br /> MCC's emergency procedures were implemented to protect the miners and save the West <br /> Elk Mine. With the restrictions on the sedimentation ponds noted above, the majority of <br />' the fault inflows was directed to the NW Panels sealed sump until eazly Mazch 1997, <br /> when water was observed seeping beneath, around, and through the seals at crosscut 14 in <br /> the 1NW tailgate; and, thus, the sump was considered "full". <br />' • Periodic observations at the seals indicated that the water level in the sump remained <br /> relatively constant indicating that there was little or no loss of water occurring. The <br />' utilization of the sump was geared toward enabling discharges to Lone Pine Gulch via a <br /> pipe through the northern-most 7NW seals (a.k.a. Lone Pine seals). However, the water <br /> level reached the seals in the 1NW headgate at crosscut 14 prior to having sufficient head <br /> at the Lone Pine seals for discharge. Consequently, the seals at crosscut 14 were replaced <br /> with new seals up-dip at crosscut 12. <br />' • Since discharges commenced in late December 1997, through the pipeline to Lone Pine <br />Gulch, the water quality of the sump water discharged has been adequate to meet <br />discharge limits. In particular, the TSS concentrations have been approximately 5 mg/L, <br />compared to influent concentrations of about 300 to 600 mg/L. <br />• MCC currently has the capacity to pump more than 2,000 gpm of water to the sealed <br />' sump and discharge up to 2,000 gpm via the Lone Pine pipeline. The dischazge permit <br />also allows discharge rates up to 2,000 gpm to Lone Pine Gulch. To date, the rates <br />pumped to and discharged from the sealed sump have roughly been equal and are <br />' typically less than 500 gpm. <br />• In February 1998, MCC completed two entries and a horizontal drill hole in the West Elk <br />Mine from the 11NE panel into the NW Panels sealed sump at the northeast comer of <br />1NW. A significant observation during the drilling of this hole was that there was no <br />water observed in the hole until the drill was within 17 feet of the NW Panels sealed <br />' sump. This observation presents compelling evidence of the tightness, or minimal <br />hydraulic conductivity, of the B-Seam coal. <br />' • Bear accessed the B-Seam via the Clark Mine C-Seam portal and sloped down to the B- <br />Seam south of the Edwards Mine. Most of the Bear No. 3 Mine B-Seam workings are <br />overlain by C-Seam workings. The interburden thickness between the B- and C-Seams is <br />' reported on Bear's mine maps as being approximately 40 to 70 feet. <br />• There is historic evidence of high TDS water in Bear's alluvial monitoring well AA-1, <br />' beginning in 1986. According to Bear's monitoring consultant, this well has contained <br />"tea" stained water since he began monitoring in eazly 1996 (similaz in color, but more <br />diluted than the current Edwards portal spring outflow). Furthermore, a CDMG <br />