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under those areas known to be flooded. <br />(d) In the now - abandoned Hawk's Nest Mine several drill holes were drilled <br />down from the active mine into lower seams. It is believed that these <br />holes are not sealed and could provide a conduit for water to flow into the <br />Sanborn Creek mine; however, as reported in the PHC, there was no <br />evidence of flooding of the mine at the time of this renewal. <br />Mine inflow, except that used in the mining process, will be treated and <br />discharged to the North Fork. The discharge will meet NPDES standards, but <br />it is expected that the discharge will have an elevated TDS for which there are <br />no discharge standards. From recent water quality analyses, TDS values of <br />3,200 mg /l for the discharge can be expected. During the emergency mine <br />water discharge of the Sanborn Creek Mine in 1999, water quality analyses of <br />the discharge water showed TDS ranging from a low of 2668 mg /l to a high of <br />4785 mg /1. <br />Post - mining impacts are expected to be small. The Sanborn Creek mine is <br />expected to slowly flood to the level of the river, which is below the elevation <br />of the portal. Discharge from the portal is unlikely. The water quality of the <br />flooded workings is anticipated to be the same as that of the old Somerset <br />Mine. After mine closure, the proposed Sanborn Creek area is not expected to <br />contribute additional dissolved solids to the river. <br />The Elk Creek Mine, based on data from other mines in the vicinity, should not <br />experience problems with inflow or eventual discharge from the portal. <br />Inflows experienced in the vicinity include 115 gpm in the B seam at Oxbow, <br />15 gpm in the C seam at Oxbow, and very little water at all in the D -seam in <br />Bowie I and II, with inflows of approximately 10 gpm. These inflow totals led <br />to the conclusion that there is little likelihood of eventual discharge from the <br />portals. <br />In October 2004, the Division approved TR -47, which proposed to transfer <br />mine sump water from the D -Seam to the underlying abandoned C seam <br />workings at a rate of up to 3 million gallons per year via a surface borehole <br />located in the upper Elk Creek facilities. A description of the operation is <br />found on Page 2.05 -96b. <br />A similar mine water transfer operation was proposed for the Hubbard Creek <br />Fansite facility, and approved under TR -51 in September 2005. With this <br />operation, D -Seam water may be transferred to the B -Seam workings. <br />2. Effects on Surface Water <br />The areas of surface disturbance at the Somerset Mine are protected by <br />sediment control systems including diversion and containment ditches, <br />sediment ponds, and other alternate sediment control features such as rock, <br />22 <br />