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Surface Water Effects <br /> With the exception of two small area exemptions, all runoff from the disturbed <br /> area at the mine site will be routed through sediment ponds. Effects of mining <br /> on this water will involve changes in the magnitude and duration of runoff and <br /> changes in water quality. <br /> The effects on water quantity are expected to be minimal. A decrease in <br /> permeability due to the construction or roads and buildings can be expected to <br /> cause an increase in runoff amounts. The rate of runoff will increase over <br /> natural conditions because of the increased efficiency of conveyance channels. <br /> However, these effects are moderated by the detention of runoff in the pond and <br /> subsequent evaporation of pond water. In general, only slight changes in the <br /> hydrologic balance of surface water are expected due to the underground mining <br /> operations proposed at the King I and II Mines. <br /> Changes in water quality can be expected to occur as a result of mining. <br /> Increases in erosion rates are expected from the disturbance of soils and <br /> vegetation; however, these are compensated by deposition of sediment in the <br /> sediment ponds. An increase in total dissolved solids (TDS) may occur from <br /> well water pumped and used for dust suppression and other operational use. <br /> Evaporation of water standing in the ponds may also cause an increase in TDS, <br /> although the increase above background concentrations (1500-2000 mg/1) is not <br /> expected to be large. <br /> The Division has determined that probable hydrologic effects on surface water <br /> identified above will not preclude use of the water below the point of discharge <br /> from the mine. This conclusion is based on the small and infrequent flows <br /> relative to the large amount of dilution available in receiving waters. The quality <br /> of surface water is limited on site and the treatment systems should act to <br /> mitigate any adverse effects on surface water. <br /> Protection of Hydrologic Balance <br /> Pursuant to Rule 2.07.6(2)(c), the Division has assessed the probable hydrologic <br /> impacts to ground water and surface water at the King I and II Mines. The <br /> Division finds that the mine operations have been designed to prevent material <br /> damage to the hydrologic balance outside the permit area. Discussion on the <br /> probably hydrologic consequences may be found in King I Appendix 4(6). <br /> IV. Topsoil <br /> The baseline soil inventories for the King I and II Mines are presented in Section <br /> 2.04.9 of the permit application. Topsoil replacement is described in Section 2.05.4. <br /> 18 <br />