2015-01-26_REPORT - C1981020 (5)

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2014 AHR McClane & Munger Canyon Mines Page 4 Future Water Inflow When mining resumes development will be to the south where the coal seam is relatively dry. Since most of the water generated in the mine comes from the sealed areas in the north, the water inflow should be relatively constant or slowly decreasing. 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. 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. Munger Canyon Mine The Munger Mine has been sealed and the disturbed areas were graded and seeded in 2007. 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. Precipitation Because of budget restraints, the Bureau of Land Management did not monitor the rain gage in Ashford Canyon. Therefore, there is no precipitation data to report for 2014. Effect of the Mine on the East Salt Creek Regime Surface Water Due to the limited disturbance of the mines there is little chance any significant 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. Due to low flow conditions, samples were only taken at SW -1 during the first and second quarter of 2014 and SW -8 during the second quarter 2014. Results are shown in Table 4. Historically, results from the samples collected from East Salt Creek above and below the mine site are generally the same for all parameters. The McClane Canyon Mine only discharged to East Salt Creek during October 2013. A routine quarterly wet tests was performed. No pattern of toxicity was found.