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coal and overburden, calculations have shown that these flows should be minor. <br />The flows can be expected to occur with a considerable lag time. There will be <br />a comparable diminution of flow in the North Fork but mine pumpage will <br />return this amount to the river, minus that used in the mine. The cone of <br />depression from dewatering of the strata will only extend to the boundary of the <br />North Fork and will not adversely impact any wells. <br />2. The potential exists that the mine may encounter water inflow from faults and <br />fractures. No particular faults have been identified. The largest fault that the <br />old Somerset Mine encountered had a sustained inflow of 120 gpm, which <br />contributed 50 percent of the total inflow. <br />The Sanborn Creek workings undermined portions of two abandoned mines - <br />the Oliver Mine and the Hawk's Nest Mine. The Oliver Mine was mined in the <br />1930's and is thought to be flooded. An exposure of the workings adjacent to <br />the old county road formerly discharged water at a rate of a few gallons per <br />minute. About 90 percent of the workings of this mine lay downdip of the <br />discharge point. <br />The Hawk's Nest Mine lies north of the Oliver Mine and is stratigraphically <br />higher than the Oliver D seam. Hawk's Nest mined in both the E and F seams. <br />The workings of this mine are probably not flooded, as indicated by <br />measurements in an old drill hole. Also, during operation of the Hawk's Nest <br />Mine, there was very little inflow. <br />Because potential exists for subsidence to cause fracturing of the interburden <br />between the B seam and the flooded workings of the Oliver Mine, Oxbow <br />Mining, LLC limited extraction in the Sanborn Creek Tracts under those areas <br />known to be flooded. <br />4. At the abandoned Hawk's Nest Mine, several drill holes were drilled down <br />from the active mine into lower seams. It is believed that these holes are not <br />sealed and could provide a conduit for water to flow into the Sanborn Creek <br />mine; however, as reported in the PHC, there was no evidence of flooding of <br />the mine at the time of this renewal. <br />Mine inflow, except that used in the mining process, will be treated and discharged <br />to the North Fork. The discharge will meet NPDES standards, but it is expected that <br />the discharge will have an elevated TDS for which there are no discharge standards. <br />From recent water quality analyses, TDS values of 3,200 mg /l for the discharge can <br />be expected. During the emergency mine water discharge of the Sanborn Creek <br />Mine in 1999, water quality analyses of the discharge water showed TDS ranging <br />from a low of 2668 mg /l to a high of 4785 mg /l. <br />Post- mining impacts are expected to be small. The Sanborn Creek mine is expected <br />to slowly flood to the level of the river, which is below the elevation of the portal. <br />22 <br />