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of the mine inflow water would be discharged to a normally dry drainage located below <br />the proposed mine portal. The point of discharge would be located approximately 40,000 <br />feet upstream from East Salt Creek. <br />Because of the normally dry condition of the unnamed tributary to East Salt Creek that <br />would receive mine water discharge (50 gpm), it is highly unlikely that surface water <br />would ever reach East Salt Creek because of seepage losses within the channel. <br />Assuming a moderately low hydraulic conductivity for the alluvium in the unnamed <br />tributary of about 15 ft/day (silt to silty sand (Freeze and Cherry 1979), an approximate <br />distance for surface water flow can be calculated. Although the alluvium is likely thin in <br />the upper most reaches of this tributary where the Mancos Shale is near the surface, the <br />alluvium is likely relatively thick along most of the tributary. At a discharge rate of 50 <br />gpm, surface flow would extend down the drainage from the portal less than 1,000 feet. <br />This does not consider losses due to evaporation or transpiration (ET), which could be <br />considerable if there is any ponding or increased vegetation growth, resulting from the <br />• new source of water. Conservatively, surface water flow would extend down the <br />unnamed tributary less than 3% of the total distance to East Salt Creek and would not <br />extend beyond the permit boundary. <br />Water quality data from East Salt Creek above and below the nearby McClane Canyon <br />Mine are reported in Tables 1A and 1B. The water quality of mine inflow to the Red <br />Cliff mine is expected to be similar to that observed at the McClane Canyon Mine (Table <br />2). The McClane mine inflow water quality is very similar to the ambient surface water <br />quality in East Salt Creek, and in general, contains lower total dissolved solids <br />(comparing Tables 1 A, 1 B, and 2). It is likely that bedrock ground water naturally <br />discharges to the surface water drainages, such as East Salt Creek, that drain the Book <br />Cliffs. <br />Nearby A VFs <br />Two larger drainages (East Salt Creek west of the study area and Big Salt Creek east of <br />the study area) contain AVFs, as identified in OSM reconnaissance mapping (OSM <br />ERO Resources Corp. Page 4 <br />AVF Determination - Red Cliff Mine 611912008