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site (typically test pit excavation/soils boring, and backfilling and leveling of the resultant small area /auger -hole, <br />occurs in a continuous sequence within the course of less than two hours for each location). The geotechnical <br />investigation activities do not involve the use of water and are conducted under dry conditions, so the potential for <br />related hydrologic impacts is negligible. <br />All geotechnical disturbance is reseeded by broadcast seeding within 6- months of disturbance, although natural <br />revegetation typically occurs much sooner due to the limited timeframe and extent of the associated disturbance. <br />Occasionally perforated PVC pipe may be inserted in a completed borehole, and the remainder of the hole <br />back:filled with clean gravel, as a temporary piezometer installation to measure any fluctuation in water- levels. <br />This type of piezometer installation is normally very temporary (typically used less than a month) and will not <br />impact groundwater due to the shallow depth and use of natural cuttings as backfill. Any piezometer installations <br />are reclaimed by either pulling the PVC pipe and placing additional fill, or plugging the PVC pipe in -place using <br />bagged bentonite grout, then capping the installation with a minimum 1.5 -foot surface plug of natural clays or <br />cement with a site marker. <br />18 -Left Ventilation Shaft Installation (TR09 -66) <br />Approximately 420 feet of the light -use road crosses upland areas, where road construction will involve removal of <br />any large vegetation and stripping and stockpiling of other vegetation, soil, and organic materials. Similarly, the <br />shaft pad is located in an upland area. In order to reestablish effective vegetative cover, TCC will recover and <br />stockpile a maximum of 18 inches of soil material from shaft disturbance areas. With a total road disturbance area <br />of approximately 0.3 acres, approximately 750 cubic yards of soil will be salvaged from the road corridor, and <br />12,800 cubic yards from the 5.3 acre pad area. The soil salvage volumes are indicated on Table 49A. Prior to <br />initiating soil removal activities, temporary sediment control, in the form of wattles and/or silt fences, will be <br />installed downgradient of the road and pad to control runoff and sediment. Soil materials will be salvaged and <br />placed in two soil material stockpiles. The stockpiles are located where they will not be subject to vehicle traffic or <br />erosion from runoff, will be stabilized by seeding with TCC's temporary seed mix, and topsoil signs will be posted. <br />• (5) Topsoil. A narrative explaining the method of removal and the amount to be removed and the plan for <br />storage of topsoil, subsoil, and other material within the permit area subject to requirements of the topsoil removal <br />er�formance standards of 4.06.2. This narrative shall specify the depth of material to be salvaged from all disturbed <br />areas based on the soil information required by 2.04.9 and shall specify the volume of each type of material to be <br />salva£ >ed. A map of any proposed storage structures shall accompany the narrative The maps shall be prepared <br />according to the requirements of 2.10. <br />RESPONSE <br />See response to 2.05.4, Reclamation Plan, below for details concerning the Foidel Creek Mine. Twentymile Coal <br />Company does not propose to disturb any additional land within the Fish Creek Tipple permit area. The Fish Creek <br />Tipple: and adjoining haulroad were constructed prior to the promulgation of regulations mandating topsoil salvage <br />and storage. Thus, the best plant growth medium available is a mixture of spoil and soil materials which will be <br />substituted for topsoil. This situation is further discussed within the Fish Creek Tipple/Loadout Appendix, pages <br />2.04 -36 through 2.04 -38 and pages 2.05 -37 through 2.05 -38 of Volume VIII. <br />Eastern Mining District Dewatering Facility - The Eastern Mining District Dewatering Facility will require <br />salvaging and stockpiling approximately 13,360 CY of topsoil from the access road and the facility site. During <br />upgrading of the road, approximately 3,600 CY of topsoil will be windrowed to the side of the road. The topsoil <br />along the length of the road is approximately 30 inches deep. The facility site will require salvaging and <br />stockpiling approximately 8,300 CY of topsoil. The topsoil from the site area is approximately 30 inches deep. A <br />test pit will be dug to verify the topsoil depth obtained from previous soil mapping work. The stockpiled topsoil, <br />which is located within the pad area, will be stabilized with the topsoil stockpile stabilizing seed mixture. <br />Additionally, approximately 6,295 CY of topsoil will be salvaged from the treatment pond site. This site has been <br />• <br />relocated closer to the road to facilitate delivery of chemicals. <br />Bleeder Fan - The bleeder fan facility will require salvaging and stockpiling approximately 4,700 CY of topsoil <br />from the access road and the facility site. During the upgrading of the road, approximately 2,800 CY of topsoil will <br />MR 10-243 2.05 -84.8 <br />05/31/10 <br />