2010-09-02_PERMIT FILE - C1982056A (3)

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In May 2003, a second borehole is to be drilled in the same general area as the first boring, for a similar use. The location of the second boring is illustrated in Map 24. This boring will be 8 -inch diameter, cased with 6 -inch diameter steel piping. The piping will be grouted in place and connections made at the top and bottom for completing the airline. • When the line(s) are no longer needed, the airline tubing will be grouted in place and the remainder of the facility removed from the site. The usable equipment will be salvaged for later use. Site 109 Diversion The diversion will consist of a 6 inch PVC PIP irrigation pipe attached to the existing 109 riser. This line will be buried and will cross the existing berm immediately to the north of the 109 riser. From that point, the line will parallel the berm, crossing the roadway near the operations center at a depth of approximately 3 feet. Should ground conditions warrant it, an 8 -inch diameter steel pipe will be installed to act as a protective sleeve for the PIP pipe where it crosses the road. The line will then be buried along the berm until reaching the east end of the heavy- equipment pad, where the line will make a 45' turn to the north and pass under the PM Bay access road. Again, a protective steel pipe sleeve may be installed should conditions warrant it. From the PM Bay Road down to the existing Site 114 vertical culvert the line will be buried to a depth of 6 -8 feet. At Site 114, the existing culvert, which has been backfilled with washed rock, will be utilized as an infiltration point, with the line entering the culvert at a depth of not less than 6 feet. Water will then infiltrate into the spoils and replenish the aquifer prior to being pumped from Site 114 to the million- gallon tank and thence underground. Line location is shown on Map 24. In order to increase operational flexibility, the Site 109 Diversion may be plumbed directly into the line- feeding Site 114. Therefore, when this option is exercised all the water from site 109 will be diverted to site 114. An underground rock filter was installed along the six -inch water line at the location shown on map 24. The rock filter is needed to help filter the water discharged from the underground mine before it is placed into the million gallon tank. The rock filter will be constructed by excavating the existing spoil material to a depth of approximately 15 - 20 feet and . placing a gravel pack in the excavated area. Prior to excavating the spoil material, the topsoil will be stripped from the site and temporarily stockpiled adjacent to the area to be excavated. The disturbance associated with the construction of the filter is approximately 0.06 acres. After the gravel has been placed in the excavation, the gravel extends to within approximately 2 feet of the surface and encompasses an area of approximately 15 x 15 feet, the spoil material will be placed back into the remaining open excavation. The spoil will be graded to blend with the topography and the topsoil reapplied. The topsoil will be seeded with the pastureland seed mixture. It is anticipated that the topsoil will be redistributed during late March or early April, depending on field conditions. The disturbance lies upstream of a rock filter dam, which controls runoff from the area. The combination of the rock filter, vegetation filter and rapid reclamation of the site will provide secondary sediment control for the site. Stock Water Pond Line A stock water pond water -line was tied into TCC's existing No. 6 well and water can be pumped up to a pond located on the bond release area south of the portal area. The location of the buried line is shown on Map 24, Surface Facilities. The line will remain after reclamation, so no reclamation or bond information is included. Material Disposal Area A solidified waste disposal area is proposed near the low- quality coal stockpile. Materials to be buried in this area would be comprised primarily of hydrocarbon contaminated materials (such as floor -dri) which are non - hazardous and are solidified by mixing with cement. The solidified waste would be buried in the old spoils on the east storage pad (above the dry storage building) as shown on Map 24. Spoil material would be excavated to a depth of 5 -10 feet, and would be set to the side until the solidified material had been placed into the excavation. The excess spoil • material would then be used to backfill the remaining void and cap the solidified material. Any extra spoil material will either be stockpiled or spread across the pad area. Placement of the solidified material would likely progress along the pad from east to west, with placement occurring over a number of episodes. Once the area has been MR 10 -246 2.05 -21 08/16/10