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(4.05.18(1)). <br />F. Probable Hydrologic Consequences <br />The anticipated impacts of the Munger Canyon Mining operation on the quality and <br />quantity of ground water and surface water in the area are minimal. This is due mainly <br />to the limited extent of underground workings and small area of surface disturbance <br />related to the mine, as well as the characteristics of the ground water environment. <br />The operation has affected approximately 39.6 acres in the Munger Canyon watershed, <br />with an existing surface disturbance of 21.2 acres and approximately 20 acres of <br />underground workings. There will be no expansion of underground workings. <br />Compared to the total drainage area in the Munger Canyon watershed (5085 acres), <br />approximately seven -tenths of a percent of the Munger Canyon drainage are impacted <br />by the operation. Although increases in concentrations of total dissolved solids (TDS) <br />and total suspended solids (TSS) are expected to result from the disturbance, the areal <br />comparison indicates that the significance of the increases in TDS would be diminished <br />due to dilution, and TSS will be controlled by the small area exemption sediment <br />controls, and stabilization seeding. Furthermore, once the runoff from the Munger <br />watershed reaches the East Salt Creek Valley, the impact would be diminished further. <br />The disturbance due to the portion of the operation situated in Munger Canyon accounts <br />for less than three -hundredths of a percent of the total drainage area of East Salt Creek <br />above the confluence with Munger Canyon (67,223 acres). Disturbance in the East Salt <br />Creek valley proper is inconsequential, limited to the access/haul road that was in <br />existence prior to operations, and was upgraded in 1977. <br />There is minimal potential for the operation to deplete the quantity of flow in Munger <br />Creek and East Salt Creek due to the limited disturbance acreage and the sealed status <br />of the portals. Very little ground water was encountered during exploratory drilling in <br />and adjacent to the permit area. There has been no discharge of mine water, due to the <br />limited extent of mine workings and the sealed status of the mine. Some depletion of <br />surface water by infiltration into the mine workings through natural and mine -induced <br />fractures may occur. The amount of depletion would be minor due to the steep local <br />topography and low precipitation. The slope varies from 2v:lh to 6v:lh. <br />The very low amount of surface water runoff that does occur is concentrated in periods <br />of snowmelt and thunderstorm events. These events produce short duration, high <br />volume runoff which, when coupled with the steep topography, greatly favors surface <br />water runoff over the infiltration of water. <br />No wells or springs were identified in Munger Canyon and no ground water rights have <br />been adjudicated within a three-mile radius of the Munger Canyon Mine. There is, <br />therefore, no potential for damage to the quality and quantity of ground water in the mine <br />plan and general areas. <br />21 <br />