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The anticipated impacts of the Munger Canyon Mining operation on the quality and quantity <br />of ground water and surface water in the area are minimal This is due mainly to the limited <br />extent of underground workings and small area of surface disturbance related to the mine, as <br />well as the characteristics of the ground water environment. <br />The operation has affected approximately 36 acres in the Munger Canyon watershed, with an <br />existing surface disturbance of 17.9 acres and approximately 20 acres of underground <br />workings. There will be no expansion of underground workings, and only very limited <br />additional surface disturbance (construction of low water crossings following culvert <br />removal along the haul road during the final phase of reclamation operations). Compared to <br />the total drainage area in the Munger Canyon watershed (5085 acres), approximately <br />seven - tenths of a percent of the Munger Canyon drainage are impacted by the operation. <br />Although increases in concentrations of total dissolved solids (TDS) and total suspended <br />solids (TSS) are expected to result from the disturbance, the areal comparison indicates that <br />the significance of the increases in TDS would be diminished due to dilution, and TSS will <br />be controlled by the sediment pond, small area exemption sediment controls, and <br />stabilization seeding. Furthermore, once the runoff from the Munger watershed reaches the <br />East Salt Creek Valley, the impact would be diminished further. The disturbance due to the <br />portion of the operation situated in Munger Canyon accounts for less than three- hundredths <br />of a percent of the total drainage area of East Salt Creek above the confluence with Munger <br />Canyon (67,223 acres). Disturbance in the East Salt Creek valley proper is inconsequential, <br />limited to the access/haul road that was in existence prior to operations, and was upgraded in <br />1977. <br />There is minimal potential for the operation to deplete the quantity of flow in Munger Creek <br />and East Salt Creek, due to the limited disturbance acreage, sealed status of the portals, and <br />existence of only a single small impoundment, with water storage of less than 1 acre -foot. <br />The pond will be dewatered following any major storm event, thereby returning stored runoff <br />to the system. Due to the low annual precipitation in the area, it is expected that very little to <br />no water will be stored in the impoundment most of the time. Very little ground water was <br />encountered during exploratory drilling in and adjacent to the permit area. There has been no <br />discharge of mine water, due to the limited extent of mine workings and the sealed status of <br />the mine Some depletion of surface water by infiltration into the mine workings through <br />natural and mine - induced fractures may occur. The amount of depletion would be minor due <br />to the steep local topography and low precipitation. The slope varies from 2v: to 6v: lh. <br />The very low amount of surface water runoff that does occur is concentrated in periods of <br />snowmelt and thunderstorm events. These events produce short duration, high volume <br />runoff which, when coupled with the steep topography, greatly favors surface water runoff <br />over the infiltration of water. <br />No wells or springs were identified in Munger Canyon and no ground water rights have been <br />adjudicated within a three -mile radius of the Munger Canyon Mine. There is, therefore, no <br />potential for damage to the quality and quantity of ground water in the mine plan and general <br />23 <br />