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The mine portal is located at the crop line <br />T here are no historic springs in the area <br />None of the historic underground mines in the area are know to discharge, and the No.9 Mine portal is at a <br />higher elevation than any of the old mines <br />Effects of Seepage from No 9 Portal Backfill <br />The No.9 Mine portal backfill will have surface area of approximately five acres. Using an infiltration <br />rate of three inches per year, the annual infiltration will be less than 1 gpm. This amount is insignificant <br />and will, therefore, have no measurable effect on nearby aquifers. Also, the backfill area is <br />stratigraphically separated from the nearest aquifer, the Twentymile Sandstone, by 360 feet of very low <br />permeability interbedded claystone, siltstones, and sandstones. <br />No 5 and No 6 Mine -Water Handling System <br />The No.5 and the No.6 mine -water handling system will be reclaimed when it is no longer needed at the <br />BTU EC mine complex. The area in which the ponds and boreholes are located will be returned to the <br />approved pasture land -use. <br />The first step, as in all reclamation activities, is the removal of all - surface structures and facilities. This <br />will include the electrical substation; chemical feed station, and borehole covers. These structures and <br />facilities will be removed from the site and salvaged or scrapped. Once the facilities and structures are <br />removed from the site, the piping will be removed from the ponds and the protective covering around the <br />boreholes will be removed. Any excess embankment material will be used as backfill at the various portal <br />locations. All water lines, pipes, and pumps will be removed from the site. The boreholes will be sealed <br />according to requirements of Rule 4.07, Sealing of Drillholes and Underground Openings. Pads around <br />the boreholes will be reclaimed and the excess material will be used to backfill the discharge ditch leading <br />to the Williams Fork River, <br />The access road leading to the site will be reclaimed. The top six inches of the road material will either be <br />hauled to the waste disposal site, or used as road surface material on existing roads. The culverts will be <br />removed and the ditch along the side of the road will be maintained until the 5A portal area is reclaimed. <br />The entire area will then be topsoiled. The topsoil will be redistributed to a depth of 6 -12 inches. After <br />redistribution of topsoil, the material will be sampled and analyzed to determine if any amendments are <br />necessary. Reclaimed areas will be seeded with the pastureland (hayland) seed mixture. A rangeland drill <br />will be used for seeding, however, in the event the seed mixture is broadcast seeded, the seeding rate will <br />be doubled. The area will be straw mulched at a rate of two tons /acre. <br />It is possible that during site reclamation, portions of the Williams Fork River bank may be disturbed. In <br />these areas, P. Arundinacea will be added to the pastureland ( hayland) seed mixture at a rate of one <br />pound /acre. <br />The dewatering site for the 7 -North Angle will be reclaimed when it is no longer needed. Reelamat�or <br />activities will be as follows: powerline removal, building and facilities removal, and grouting of the hole. <br />Upon completion of this work, the salvaged topsoil will be redistributed over the pad and the area will be <br />reseeded and returned to cropland. <br />R07 -? <br />