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2011 AHR McClane & Munger Canyon Mines Page 4 <br />As shown on Figure 4.2 -3, the saturated strata appear to outcrop in the valley <br />formed by the north split of Munger Canyon. Since the strata in the area dip at <br />four percent to the northeast, water may be infiltrating the seam along the valley <br />bottom. Any water infiltrating the strata at this location will flow down dip until the <br />aquifer is totally saturated unless there is an area where water may escape. The <br />elevation of the saturated zone would approximate the elevation of the outcrop <br />(5,600 ft) if no water flows out of the strata at a lower elevation. There are no <br />known springs or seeps that would allow escape of the water from the zone of <br />saturation so it can be expected the coal seam will be saturated near the outcrop <br />elevation. <br />Munger Canyon Mine <br />The Munger Mine has been sealed and the disturbed areas were graded and <br />seeded in 2007. There was no water encountered in mine; therefore, there has <br />been no effect on the hydrologic regime of the area. The current mine workings <br />are shown on Figure 4. <br />Precipitation <br />Based upon Bureau of Land Management records from a rain gage in Ashford <br />Canyon, the 2011 water year experienced 21.70 inches of precipitation <br />compared to average precipitation of 17.68 inches. The rain gage is not located <br />at the mine but about 3.5 miles north at an elevation of 5895 feet compared with <br />5610 at the portals. Figure 2 presents a graphical comparison of the 2011 water <br />year total monthly precipitation and the average monthly precipitation for the <br />period 1977 through 2010. Precipitation data are obtained from the BLM <br />(NDieteri @blm.gov). <br />Effect of the Mine on the East Salt Creek Regime <br />Surface Water <br />Due to the limited disturbance of the mines there is little chance any significant <br />effect on the quantity or quality of the surface waters near either mine sites has <br />occurred. As the Division notes in its approval package for the Munger Canyon <br />Mine, the total area that will be disturbed by both mine sites amounts to 0.12 <br />percent of the area of the East Salt Creek drainage basin above the mines. <br />Surface water samples from East Salt Creek were obtained all four quarters <br />during the water year at monitoring station SW -1 and SW -8. The results from all <br />water samples collected during the water year are presented in Table 4. Due to <br />the mine being idle, the sampling required for the first through fourth quarters in <br />2011 were based on an approved short list of parameters for temporary <br />cessation. The results from the samples collected from East Salt Creek above <br />and below the mine site are generally the same for all parameters. <br />The McClane Canyon Mine discharged to East Salt Creek during March of 2011. <br />