2011-04-18_REPORT - C1996083 (2)

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Introduction 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 were virtually dry. Development in panels B4, B5, and a portion of B-6 developed during 2007 were also considered dry. The B-Seam has hit steadily increasing water inflows beginning in 2008. The inflow is predominantly from sandstone channels. As of the end of May 2008, the mine inflow was about one million gallons per day (-700 gpm). Much of the inflow is from sandstone channels around the B-8 panel. As of August 2008 the mine inflow had reduced to about 350 gpm. At the end of 2008 the mine inflow had increased to over 500 gpm. The mine inflow was recorded at 340 gallons per minute based on a July 2009 mine inflow report. • During 2009 the water produced in the mine was stored in the mined out B-1 through B-3 panels and discharged through outfall 006. Discharge from outfall 006 at times approached 1,000 gallons per minute. Average discharge from outfall 006 was 210 gpm. 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 and 2009 point sources of mine inflow were monitored. During 2010 the mine abandoned the northeast area of the mine and began mining to the west. The were no significant mine inflows in the 1 west mains or in the initial development of longwall Panel B-10. 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 2010 calendar year, the Bowie No. 2 Mine consumed 138.3 AC- FT of water in order to produce 1,325,000 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