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The water within the perched aquifer flowing into the mine probably <br />• comes from surface water infiltration along the faults east and west <br />of the mine. This assumption is supported by the cyclical nature of <br />water inflow corresponding with periods of precipitation. Both <br />faults have ephemeral drainages crossing their surface trace near <br />the mine end may receive water from the drainages. The water then <br />infiltrates the coal seam which has become saturated over time. <br />MUNGSR CANYON MINE <br />To date there has been no water encountered by this mine; therefore, <br />there has been no effect on the hydrologic regime of the area. A <br />current mine workings map is included as Figure 2 and Table 1 <br />documents that there has been no water imported or used at the mine. <br />PRECIPITATION <br />The 1991 water year was a near normal year. Total precipitation of <br />16.95 inches was BB percent of average for the last ten years. <br />Since about half of the rainfall occurred during three months, there <br />were both dry and wet spells during the year. Notable events <br />occurred during the first two days of August when there was about <br />2.5 inches of rainfall. The storms were both intense and dropped <br />the equivalent of a 100 year event at the mine over a 28 hour <br />period. Surface water samples for the third quarter were gathered <br />on the first day of the storms. <br />• EFFECT OF THS MINES ON THS BAST SALT CREEK REGIME <br />Surface Water <br />Due to the limited disturbance of the mines there is little chance <br />that any significant effect on the quantity or quality of the <br />surface waters near either mine sites has occurred. As the Division <br />notes in its approval package for the Munger Canyon Mine, the total <br />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 <br />mines. <br />Surface water samples are being taken on McClane Creek (SW-2 and <br />SW-5), Munger Creek (SW-3), and Sast Salt Creek (SW-1 and SW-8) as <br />required by the monitoring program. Results of the quarterly <br />sampling for each of the monitoring sites are shown on Table 4. <br />Additional samples are occasionally taken at other sites and results <br />are also included in Table 4. Both McClane and Munger Creeks were <br />dry most of the year as is normal. The results of surface water <br />sampling ere significant in that this is the first time that en <br />intense storm event has been monitored with water sampling. <br />\J <br />Page - 3 <br />