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greater than the head exerted by the mine water. The State Engineer's records show two wells have been completed in the Cliffhouse Sandstone approximately one mile downgradient from the King Coal Mine workings (the V. Paulek and G. Paulek wells). Menefee Formation -Like the Cliffhouse Sandstone, mining impacts to the Menefee Formation are improbable because it is unlikely the workings of the King Coal and King II Mines will fill with water. Ground water points of compliance are not warranted for the Hay Gulch alluvium, Phe Menefee Formation, the Cliffhouse Sandstone, or the Point Lookout Sandstone because, as explained above, the King Coal and King II Mines lack the potential to negatively impact these units. Surface Water Effects With the exception of two small azea exemptions, all runoff from the disturbed area at the mine site will be routed through sediment ponds. Effects of mining on this water will involve changes in the magnitude and duration of runoff and changes in water quality. The effects on water quantity aze expected to be minimal. A decrease in permeability due to the construction or roads and buildings can be expected to cause an increase in • runoffamounts. The rate of runoffwill increase over natural conditions because ofthe increased efficiency of conveyance channels. However, these effects are moderated by the detention of runoff in the pond and subsequent evaporation of pond water. In general, only slight changes in the hydrologic balance of surface water are expected due to the underground mining operations proposed at the King Coal Mine. Changes in water quality can be expected to occur as a result of mining. Increases in erosion rates are expected from the disturbance of soils and vegetation, however, these are compensated by deposition of sediment in the sediment ponds. An increase in total dissolved solids (TDS) may occur from well water pumped and used for dust suppression and other operational use. Evaporation ofwater standing in the ponds may also cause an increase in TDS, although the increase above background concentrations (1500-2000 mg/1) is not expected to be large. The Division has determined that probable hydrologic effects on surface water identified above will not preclude use of the water below the point of dischazge from the mine. This conclusion is based on the small and infrequent flows relative to the large amount of dilution available in receiving waters. The quality ofsurface water is limited on site and the treatment systems should act to mitigate any adverse effects on surface water. • 18