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<br />t <br />Monitor holes 2-7L and TW2-7L are on the same location and apparently also responded to <br />the two leaking exploration holes. Longwall panel 3 was mined past this location in April 1990 <br />t and the water level had dropped below 300 feet. Longwall panel 4 was mined past this <br />location in August 1991. Well 2-7L has a dry blockage at 650 feet while TW2-7L has a dry <br />blockage at 660 feet. <br />' During this monitoring period, the average water level in monitor hole 36-2L has remained <br />t unchanged at a depth of 188 feet. Monitor hole 35~L was found to have a dry obstruction at <br />438 feet. The 35-4 location was mined through in October 1994. The hole is venting air and <br />has been capped. <br />' Monitor hole 4-20L showed a relatively static water level of 237.0 feet during this monitoring <br />' period. <br />The response of "lower sandstone facies" monitoring holes 2-17L, 2-7L and TW2-7L to mining <br />' and leaking exploration holes indicates the area of influence in the "lower sandstone facies" is <br />larger than that in either the "upper sandstone facies" or the "siltstone-coal facies". However, <br />' the response of these monitoring holes to low flows of about 1 gpm in the leaking exploration <br />holes further indicates the low water flow characteristics of the "lower sandstone facies". <br />' From the baseline data, all three zones should be classified as "aquitards" in that they will <br />yield water but at very slow rates. Mining in the D Seam so far has encountered only small <br />' flows of water and the mine is essentially dry. Previously, water leaking out of caved areas <br />was routed to the sumps at the end of gateroads. From there it was pumped to the surface <br />through boreholes and discharged. The boreholes were designated as sump dewatering <br />holes (SDH2, SDH3, SDH5, and SDH6, see Plate 1). The dewatering hole SDH6 was never <br />drilled, and will not be drilled, because of the abandonment of the mining area due to the mine <br />' fire. The quantity and quality of this water is discussed in Section 2.2.2.5. No underground <br />water has been pumped out of these locations since the January 31, 1996 underground fire <br />episode. <br />' 2.2.1.4 Bedrock Water Quality Water sampling and analysis are no longer required from <br />' the bedrock monitoring holes. However, as required by DMG, prior to entering Federal leases <br />C-8424 and C-8425, one water quality sample was collected and analyzed from each of the <br />monitoring holes in federal leases C-8424 and C-8425. Such sampling was limited to the <br />' middle (coal facie) zone <br /> <br />io <br />1 <br />