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Fntnre 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 possible that water will be encountered . Figure 4.2- 3, of the permit application, shows that the saturated strata may again be encountered approximately 400 feet ahead of where milting stopped in 1997. This location is near the eastern edge of Figure 3, Mine Map. If water is once again encountered, its existence will be documented and detailed in future reports. As shown on Figure 4.2-3 the saturated strata appear 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 a]ong the valley bottom. Any water infiltrating the strata at this location will flow down dip unti] the aquifer is totally saturated unless there is an azea 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 5636 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 that the coal seam will be saturated near the outcrop elevation. MIINGER CANYON MINE To date there has been no water encountered by this mine; therefore, there has been no effect on the hydrologic regime of the area. A current mine workings map is included as Figure 4. Table 1 documents that no water was used at the mine this year. PRECIPITATION Based upon Bureau of Land Management records from a rain gage in Ashford Canyon, the 1998 water yeaz experienced near average amounts of precipitation, 18.03 inches. The average annual precipitation since monitoring began in 1977 has been about 16.55 inches. There were no record high or low precipitation months. As depicted on Figure 2, only two months had significantly higher than normal precipitation, February and March. The rain gage is not located at the mine but about 3.5 miles north at an elevation of 5895 feet compared with 5610 at the portals. The daily rainfall record is detailed on Table 2 and graphed on Figure 2. No major precipitation events occurred during the year. The largest was 0.77 inches on February 27th . It was followed the next day by a 0.75 inch event. No discharge from the sediment pond was necessary. In fact the pond was dry in early June and was completely cleaned. To date the pond has not experienced any real inflows and remains dry except for a small pool of water. EFFECT OF THE MINES ON THE EAST SALT CREEK REGIME Surface Water Due to the limited disturbance of the mines there is little chance that any signiScant effect on the quantity or quality of the surface waters near either mine sites has occurred. As the Division notes in its approval package for the Munger Canyon Mine, the total area that will be disturbed by both mine sites amounts to 0.12 percent of the area of the East Salt Creek drainage basin above • the mines. AHR - 98 Page - 3 l 1 - 23 - 98