2014-10-15_PERMIT FILE - C1982056A (7)

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borings (up to 30 feet) using a hollow -stem auger, and/or excavation of shallow (up to 15 feet) test pits. For both soils borings and test pits, surface disturbance is minimal (no more than 10 x 10 feet for boreholes, and 10 x 15 feet for test pits) and both disturbance and subsequent stabilization occur within a timeframe of less than one day for each site (typically test pit excavation/soils boring, and backfilling and leveling of the resultant small area/auger -hole, occurs in a continuous sequence within the course of less than two hours for each location). The geotechnical investigation activities do not involve the use of water and are conducted under dry conditions, so the potential for related hydrologic impacts is negligible. All geotechnical disturbance is reseeded by broadcast seeding within 6- months of disturbance, although natural revegetation typically occurs much sooner due to the limited timeframe and extent of the associated disturbance. Occasionally perforated PVC pipe may be inserted in a completed borehole, and the remainder of the hole backfilled with clean gravel, as a temporary piezometer installation to measure any fluctuation in water - levels. This type of piezometer installation is normally very temporary (typically used less than a month) and will not impact groundwater due to the shallow depth and use of natural cuttings as backfill. Any piezometer installations are reclaimed by either pulling the PVC pipe and placing additional fill, or plugging the PVC pipe in -place using bagged bentonite grout, then capping the installation with a minimum 1.5 -foot surface plug of natural clays or cement with a site marker. (5) Topsoil. A narrative explaining; the method of removal and the amount to be removed and the plan for storage of topsoil, subsoil, and other material within the permit area subject to requirements of the topsoil removal performance standards of 4.06.2. This narrative shall specify the depth of material to be salvaged from all disturbed areas based on the soil information required by 2.04.9 and shall specify the volume of each type of material to be salvaged. A map of any proposed storage structures shall accompany the narrative. The maps shall be prepared according to the requirements of 2.10. RESPONSE See response to 2.05.4, Reclamation Plan, below for details concerning the Foidel Creek Mine. Twentymile Coal Company does not propose to disturb any additional land within the Fish Creek Tipple permit area. The Fish Creek Tipple and adjoining haulroad were constructed prior to the promulgation of regulations mandating topsoil salvage and storage. Thus, the best plant growth medium available is a mixture of spoil and soil materials which will be substituted for topsoil. This situation is further discussed within the Fish Creek Tipple/Loadout Appendix, pages 2.04 -36 through 2.04 -38 and pages 2.05 -37 through 2.05 -38 of Volume VIII. Eastern Mining District Dewatering Facility - The Eastern Mining District Dewatering Facility will require salvaging and stockpiling approximately 13,360 CY of topsoil from the access road and the facility site. During upgrading of the road, approximately 3,600 CY of topsoil will be windrowed to the side of the road. The topsoil along the length of the road is approximately 30 inches deep. The facility site will require salvaging and stockpiling approximately 8,300 CY of topsoil. The topsoil from the site area is approximately 30 inches deep. A test pit will be dug to verify the topsoil depth obtained from previous soil mapping work. The stockpiled topsoil, which is located within the pad area, will be stabilized with the topsoil stockpile stabilizing seed mixture. Additionally, approximately 6,295 CY of topsoil will be salvaged from the treatment pond site. This site has been relocated closer to the road to facilitate delivery of chemicals. Bleeder Fan - The bleeder fan facility will require salvaging and stockpiling approximately 4,700 CY of topsoil from the access road and the facility site. During the upgrading of the road, approximately 2,800 CY of topsoil will be windrowed to the side of the road and left in place. The 1,200 CY that will be salvaged from the road extension will be placed in the stockpile that will be established on the fan pad. In addition to the topsoil stockpiled from the road extension, approximately 740 CY will be salvaged and stockpiled from the pad. The soil resources information was derived from information presented in Exhibits 7 and 8, Soil Profile Description and Soil Mapping Unit Descriptions, Map No. 19, Mine No. 3, Soils presented in permit C -84 -062. These materials are incorporated herein by reference. At the bleeder fan site, Twentymile will establish a test pit to verify topsoil depths prior to salvaging topsoil. The stockpiled topsoil, which is located within the pad area, will be stabilized with the topsoil stockpile stabilizing seed mixture. Prior to salvaging any topsoil from the site, a T & E species reconnaissance for Ute Lady's Tresses, Spiranthes diuvialis, will be conducted, and the results forwarded to the Division. It is not anticipated that this species will be found, as the site appears to be outside of its natural range. MR14 -283 2.05 -84.9 10/09/14