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not believed to be sealed and could provide a conduit through which water could flow into the active mine; however, as reported in the PHC, there is no indication that the mine is flooded. Mine inflow, except that used in the mining process, will be treated and discharged to the North Fork. The operator currently pumps approximately 250 gpm from the mine and has pumping capability to handle at least 500 gpm. The operator does have the necessary approval to discharge to the North Fork of the Gunnison River. The dischazge is expected to meet Colorado Dischazge Permit System (CDPS) standazds, but it is expected that the dischazge will have an elevated total dissolved solids (TDS). From water quality analyses of the flooded old Somerset Mine, TDS values of 3,200 mg/1 for the discharge can be expected. Post-mining impacts are expected to be small. The mine is expected to slowly flood to the level of the river, which is below the elevation of the portal. Dischazge from the portal is unlikely. The water quality of the flooded workings is anticipated to be the same as that of the old Somerset Mine. After mine closure, the proposed Sanborn Creek area is not expected to contribute additional dissolved solids to the river. Effects on Surface Water The areas of surface disturbance at the Sanborn Creek Mine are protected by sediment control systems including diversion and containment ditches, sediment ponds, and other alternate sediment control features such as rock, vegetation and straw 5lters. All point source discharges aze regulated under CDPS. Specific details regarding the sediment and drainage control systems are found in the Sanborn Creek Mine Permit, volume 1, pages 2.05-15, 2.05-16, and 2.051 through 2.05-48. Maps E8-3255, 3276, 3277, 3278, and 3279 also contain pertinent information. Drainage and sediment control information specific to the Sanborn Creek Permit Revision azea is located in the Permit Revision No. 1 binder, pages 2.05-15, 2.05-16; 2.05-43 through 48, and Appendix B. Drawings 5-002, 003 and 004 also contain pertinent information. Drainage from disturbed areas can contribute additional suspended solids to offsite stream systems; however, the above-referenced sediment control systems will effectively control sediment yield to offsite azeas. Other applicable effluent limitations will also be met, as required by the CDPS permit. There is no evidence of acid-forming or toxic-producing materials. The operation will result in slightly increased total dissolved solids levels in the North Fork of the Gunnison River. The sources are the discharge from Sanborn Crcek Mine 20 Petmit Revicioo No. 3