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2001 AHR McClane & Munger Canyon Mines Page 3 Source of Water Inflow As detailed in previous reports, the water flowing into the mine seems to be a mix of water infiltrating the graben along the faults and water in the coal seam. The zone of saturation of the coal seam was initially estimated using the results of exploration drilling. The drilling indicated that holes in the McClane graben were dry; specifically, holes 7-15-3 and 7-21-1. Additionally, a piezometer installed down dip from the mine outside of the graben has not realized water to date. Since the piezometer is down-dip and is dry it is apparent water flowing into the mine is from a perched aquifer in the area of the coal mine. The water within the perched aquifer flowing into the mine probably comes from surface water infiltration along the faults east and west of the mine. Both faults have ephemeral drainages crossing their surface trace. These faults may be one source of recharge to the perched aquifer. The water then infiltrates the coal seam which has become saturated over time. This assumption is supported by the previously documented cyclical nature of water inflow corresponding with periods of precipitation Future Water Inflow As the mine extends farther to the east and then north as shown in Figure 2.1.1 of the permit application, it is proven that water will be encountered. Figure 4.2-3, of the permit application, shows the saturated strata may again be encountered approximately 400 feet ahead of where mining stopped in 1997. During 2000 this saturated strata was encountered about 600 feet ahead of where mining stopped in 1997. This location is near the eastern edge of Figure 3, Mine Map, at about cross-cut 32 in the Main East Entries. The mine plans are to develop to the east and then to the north during 2002 so additional mine inflows/seeps may be encountered. As shown on Figure 4.2-3, the saturated strata appear to outcrop in the valley formed by the north split of Munger Canyon. Since the strata in the area dip at four percent to the northeast water may be infiltrating the seam along the valley bottom. Any water infiltrating the strata at this location will flow down dip until the aquifer is totally saturated unless there is an area where water may escape. The elevation of the saturated zone would approximate the elevation of the outcrop (5,600 ft) if no water flows out of the strata at a lower elevation. The elevation of the existing faces is approximately 5610 ft. There are no known springs or seeps that would allow escape of the water from the zone of saturation so it can be expected the coal seam will be saturated near the outcrop elevation. MONGER CANYON MINE The Munger Mine has been sealed and it is not expected to be reopened. There was no water encountered in mine; therefore, there has been no effect on the hydrologic regime of the area. The current mine workings are shown on Figure 4. Table I documents that water was used at the mine this year for dust control.