2011-03-14_REPORT - C1981022 (2)

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O Monitor well SC-3 is located east of the Sanborn Creek reclaimed mine portal area along the entrance to the pre-existing ranch road to Coal Gulch. Monitoring well SC-3 was completed into the B Seam coal. Monitoring data were collected from well SC-3 prior to any substantial mining in the B-Seam of the Sanborn Creek Mine. The SC-3 well is up-gradient relative to the B seam underground mining activities but down-gradient from the North Fork of the Gunnison River The plastic pipe casing is squeezed at the 20 foot level making it difficult to lower a bailer. Using a smaller diameter bailer we have found very minimal water available in the well. In fact there are times when the initial bailing of the well to remove one volume effectively drains the available water. The lack of water in the well and the poor water quality suggests there is little transmissivity and connection between the North Fork of the Gunnison River and the B seam coal at this particular vicinity of the mine. As the of SC-1 and SC-3 wells serve to monitor only the Rollins sandstone and B-seam coal respectively up- rag dient of the Sanborn creek mining area, their utility towards the monitoring of the Sanborn creek mine itself remains somewhat limited. 6.0 Mine Water Information Elk Creek Mine Water The water utilized in the mine continues to be all imported from the alluvial water supply well located near the North Fork of the Gunnison River per the OMLLC water rights and Augmentation Plan. Water that is collected. and routed to the underground Elk Creek mine sump generally comes from a number of sources, including overspray on mining equipment and beltlines for dust control, motor cooling and general leaks and spillage, inflow from sealed mine areas, etc. During July, 2005 a thermal event occurred in the 0 West Panel gob. Control of the event was facilitated, in part, by pumping of water into the area for cooling purposes. Subsequently, in late 2005, it was observed that the sealed 4 West and 5 West gate road areas were generating approximately 14 gpm and 12 gpm of water respectively from behind the mine seals. The water was eventually routed to the mine sump. We believed that the source of water draining from these two sealed gate roads is the water pumped into the area earlier in the year, working its way down gradient to these two low points in the mine. During 2006, the two seals noted above plus a third seal located in 4 West and 5 West panel gob flowed a combined 17.2 gpm. All flows are collected and eventually routed to the mine sump. In addition, a large perched, but temporary, water zone flowed in the west end of 10 West and flowed into the gate road. It was also collected and pumped to the mine sump. By the end of 2006, the 10 west water flow had greatly diminished to where the entire flow is now pumped just 10 minutes a day to 132132. ® During 2007, a similar perched zone flowed temporarily in the west end of 11 West and pumped to the mine sump. By the end of 2007, the 11 West water flow had greatly diminished. The 4 West and 5 West seals still flow - 17.0 gpm. 16