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Additionally, a piezometer installed down dip from the mine outside of the graben has <br />not realized water to date. Since the piezometer is down-dip and is dry, it is apparent that <br />the water flowing into the mine is from a perched aquifer in the area of the coal mine. <br />The water within the perched aquifer flowing into the mine probably comes from surface <br />water infiltration along the faults east and west of the mine. Both faults have ephemeral <br />drainages crossing their surface trace. These faults may be one source of recharge to the <br />perched aquifer. The water then infiltrates the coal seam, which has become saturated <br />over time. This assumption is supported by the previously documented cyclical nature of <br />water inflow corresponding with periods of precipitation. <br />Future Water Inflow <br />As the mine extends farther to the east and then north as shown in Figure 2.1.1 of the <br />permit application, it is proven that water will be encountered. Figure 4.2- 3, of the <br />permit application, shows that the sattuated strata may again be encountered <br />approximately 400 feet ahead of where mining stopped in 1997. This saturated strata was <br />encountered 600 feet ahead of where mining stopped in 1997. This location is near the <br />eastern edge of Figure 3, Mine Map. <br />As shown on Figure 4.2-3, the saturated strata appear to outcrop in the valley formed by <br />the north split of Munger Canyon. Since the strata in the area dip at four percent to the <br />northeast water may be infiltrating the seam along the valley bottom. Any water <br />infiltrating the strata at this location will flow down dip until the aquifer is totally <br />saturated unless there is an area where water may escape. The elevation of the saturated <br />zone would approximate the elevation of the outcrop (5,600 ft) if no water flows out of <br />the strata at a lower elevation. The elevation of the existing faces is approximately 5610 <br />ft. There are no known springs or seeps that would allow escape of the water from the <br />zone of saturation so it can be expected that the coal seam will be saturated near the <br />outcrop elevation. <br />MUNGER CANYON MINE <br />To date there has been no water encountered by this mine; therefore, there has been no <br />effect on the hydrologic regime of the area. A current mine workings map is included as <br />Figure 4. Table 1 documents that no water was used at the mine this year. <br />PRECIPITATION <br />Based upon Bureau of Land Management records from a rain gage in Ashford Canyon, <br />the 2000 water year experienced 10.91 inches of precipitation compared to average <br />precipitation of 16.28 inches. The rain gage is not located at the mine but about 3.5 miles <br />north at an elevation of 5895 feet compared with 5610 at the portals. The daily rainfall <br />record is detailed on Table 2. The greatest 24-hour precipitation event during the year, <br />0.55 inches, occurred on January 25. Figure 2 presents a graphical comparison of the <br />2000 total monthly precipitation and the average monthly precipitation for the period <br />1977 tfirough 2000. <br />3 <br />