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_28_ Probable Hydrologic Consequences The anticipated impacts of the Munger Canyon Mining operation on the quality and quantity of ground water and surface water in the area are minimal. This is due mainly to the small area of surface disturbance related to the mine, as well as the characteristics of the ground water environment. The disturbance related to the operation will encompass approximately 122 acres, 35 of which are located in P4unger Canyon. Compared to the total drainage area in Munger Canyon (5,085 acres), approximately seven-tenths of a percent of the Munger Canyon drainage will be impacted by the operation. Although increases in concentrations of total dissolved solids (TDS) and total suspended solids (TSS) are expected to result from the disturbance, the areal comparison indicates that the significance of the increases in TDS would be diminished due to dilution, and TSS will be controlled by sediment ponds. Furthermore, once the runoff from the Munger watershed reaches the East Salt Creek Valley, the impact would be diminished further. The disturbance due to the portion of the operation situated in Munger Canyon only accounts for five-hundredths of a percent of the total drainage area of East Salt Creek above the confluence with Munger Canyon (67,223 acres). A similar relationship with respect to dilution occurs for the portion of the operation situated along the East Salt Creek drainage (87 acres). This accounts for approximately 0.12 percent of the total drainage area of East Salt Creek below the confluence with Munger Canyon (72,373 acres). There is a potential for the operation to deplete the quantity of flow in f4unger Creek and East Salt Creek. This potential is slight. Water stored in impoundments will always be less than two acre-feet per structure and there are only six structures. The ponds will also be dewatered to the required storage capacity following any major storm event, thereby returning stored runoff to the system. Additionally, precipitation in the area is so low (8.8 inches annually) that it is expected that very little to no water will be stored in the impoundments most of the time. Very little ground water was encountered during exploratory drilling and around the permit area. Salt Creek Mining Company does not expect to have discharge mine water as a result of consistent inflow into the mine. Some depletion of surface water by infiltration into the mine workings through natural and mine-induced fractures may occur. The amount of depletion would be minor due to the steep local topography and low precipitation. The slope varies from 2v:lh to 6v:lh, and the precipitation is 8.8 inches per year. The very low amount of surface water runoff that does occur is concentrated in periods of snowmelt and thunderstorm events. These events produce short duration, high volume runoffs which, when coupled with the steep topography, yreatly favors surface water runoff over the infiltration of water. No wells or springs were identified in Munger Canyon and no ground water rights have been adjudicated within a three-mile radius of the Munger Canyon Mine. There is, therefore, no potential for damage to the quality and quantity of ground water in the mine plan and general areas.