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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 the underground workings at the Sanborn Creek facility, and drainage from waste piles located at the site. The previously documented discharges from the Somerset Mine no longer exist since mining and mine dewatering activities have ceased and the old portals have been permanently sealed. Specific anticipated water quality impacts are discussed within the Cumulative Hydrologic Impact Study for the North Fork of the Gunnison River. It has been found that the Somerset Mine operation, including the Sanborn Creek addition, will not cause significant salinity increase in the North Fork of the Gunnison River. The mine will not adversely impact flooding processes or streamflows in the North Fork of the Gunnison River. Mining operations are not expected to decrease flows in any of the ephemeral or intermittent drainages to be undermined. The operation will not adversely impact downstream water users. The operator will use about 35,000 gallons per day for underground and aboveground dust suppression. This water will be drawn from an existing surface water right of 1.8 cfs, on the North Fork of the Gunnison River. More detailed information is available in the CHIS for the North Fork of the Gunnison River. IV. Topsoil • 1. The Division has determined that selected overburden materials may be used for, or as a supplement to, topsoil. The resulting soil should be equal to or better than the available fill material. This determination will be based on physical and chemical analyses and field-site trials approved by the Division (4.06.2(4)(a)). Somerset Mining Company has agreed to remove and/or bury coal and coaly material on the pre-law Elk Creek yard area. Since topsoil is not available, the resulting surface material will be tested to determine if it is suitable as plant growth medium. If it is not, it will be covered by at least six inches of suitable plant growth medium or topsoil salvaged from development of the present coal mine waste pile area or the Sanborn Creek facilities areas. The areas stripped of topsoil for emplacement of the Sanborn Creek facilities will be regraded following mining, tested and treated with topsoil in a similar fashion. All stockpiled topsoil will be used in reclamation. None will be left stockpiled upon final reclamation. The topsoil stockpiled at the upper Hubbard Creek area will be used to partially cover pre-law waste piles that exist at the lower Hubbard Creek area. The upper Hubbard Creek bench will be retained as an approved USFS parking tot. V. Sealing of Drilled Holes and Underground Openings 1. The Division will require that each hole, well or other underground • opening be capped, sealed, backfilled, or otherwise properly managed (4.07.3). -16-