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2007 AHR McClane & Munger Canyon Mines Page 4 <br />Munger Canyon Mine <br />The Munger Mine has been sealed and the disturbed areas were graded and seeded in <br />2007. There was no water encountered in mine; therefore, there has been no effect on <br />the hydrologic regime of the area. The current mine workings are shown on Figure 4. <br />Precipitation <br />Based upon Bureau of Land Management records from a rain gage in Ashford Canyon, <br />the 2007 water year experienced 15.0 inches of precipitation compared to average <br />precipitation of 18.0 inches. The rain gage is not located at the mine but about 3.5 <br />miles north at an elevation of 5895 feet compared with 5610 at the portals. The daily <br />rainfall record is detailed on Table 2. The greatest 24 hour precipitation event during <br />the water year, 1.4 inches, occurred on October 6t". Figure 2 presents a graphical <br />comparison of the 2007 total monthly precipitation and the average monthly <br />precipitation for the period 1977 through 2007. <br />Precipitation data are obtained from Min L. Choy, BLM, min choy(a~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 effect on <br />the quantity or quality of the surface waters near either mine sites has occurred. As the <br />Division notes in its approval package for the Munger Canyon Mine, the total area that <br />will be disturbed by both mine sites amounts to 0.12 percent of the area of the East Salt <br />Creek drainage basin above the mines. <br />Surface water samples from East Salt Creek were obtained for all four quarters during <br />the water year at monitoring stations SW-1 and SW-8. SW-4 only had flow during the <br />1St and 3~d quarter of 2007. Apparently the landowner is consuming or storing all of the <br />flow between SW-8 and SW-4. The results from all water samples collected during the <br />water year are presented in Table 4. The results from the samples collected from East <br />Salt Creek above and below the mine site are generally the same for all parameters. <br />Table 6 contains analyses of mine water discharged into East Salt Creek. The mine <br />water had an average TDS value of 1,893 mg/I. The average TDS value for East Salt <br />Creek at SW-1 was 2,581 mg/I during the water year. Therefore, mine water discharge <br />supplemented and slightly improved the water quality in East Salt Creek during the <br />year. <br />• <br />