2008-05-01_REPORT - C1996083 (6)

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Introduction S Mine water inflow results were consistent with the predictions presented in the mining permit application. Discharged Water The D-Seam mine began discharging inflow water at a rate of approximately 5 g.p.m. from the underground workings during the fourth quarter of 2002. This water is directed from the portal areas to Sedimentation Pond C. The estimate of mine water inflow during the first two months of 2004 was about 25 g.p.m. When D9 panel was complete early in March 2004, dewatering of the D-Seam ceased. Mining in the B-Seam began in January 2004. Water was encountered as the tunnels were excavated to provide access to the B-Seam in late 2003 and water continues to be encountered. During 2004 it was estimated the B-Seam produced about 15 g.p.m. The B1, B2 and B3 panels developed during 2005 and 2006 in the B-Seam are virtually dry. Development in panels B4, B5, and a portion of B-6 developed during 2007 were also considered dry. However, development work has encountered additional water inflow rates in the 50 gallon per minute rate. During 2008 the mine started encountering additional mine inflows in the mains north of Panel B-7. That mine inflow will be further discussed in next years report. Up through 2006 there have not been any specific point sources in the D-Seam or B-Seam. Water inflow into the mine was associated with overlying igneous sills, sandstone channels or fractures in the roof or flow from fractures in the floor. The pattern of water inflow is one of steadily decreasing flow as the face mines through an area and advances away from it. During 2007 the operator did not monitor any point sources of mine inflow. During 2008 it is expected there will be point sources of mine inflow that will be monitored. Consumptive Use The Bowie No. 2 Mine extracts dust suppression and sanitary water from the Deer Trail Ditch via a pump station located on the Deer Trail ditch as shown on Map15-1 of the permit application. The pump station is metered. This meter records the consumptive use of water from the Deer Trail Ditch. During the 2007 calendar year, the Bowie No. 2 Mine consumed 256.9 AC- FT of water in order to produce 5,481,000 tons of coal. Pond evaporation is estimated at 4.8 AC-FT per year. The addition of the estimated pond evaporation to the mine consumption produces a consumptive use of 261.7 AC-FT of water for the 2007 year and is less than the estimated 323.4 AC-FT indicated in the permit application. This usage indicates that water for dust suppression and fire prevention and coal preparation at the Bowie No. 2 Mine averaged approximately 47.8 AC-FT per million tons of coal produced. Conclusions There was no water discharged from the mine during 2007. Mine Water Inflows are estimated at approximately 50 gallons per minute. Approximately 160 gallons of water per minute are introduced to the mine from the Deer Trail Ditch. Any sudden increase in mine inflow values could be reasonably incorporated into the dust suppression process. t