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constructing a sediment pond is not warranted. Sediment contributions from the small disturbed area can effectively be <br />controlled using the stated Best Management Practices (BMP's), and therefore falls under a n SAE, consistent with <br />applicable provisions of Rule 4.05.2(3)(b). The will be no discharge or mixing of mine water with surface drainage <br />from the site. Given the limited site area, agravel-surfaced pad azea, the drainage and sediment control measures, and <br />the effectiveness of the BMP's in reducing peak settleable solids concentrations to 0.23 ml/1 (modeled results), TCC <br />submits that an SAE is justified for this site. The estimated peak flow and runoff from the site for the 10-year, 24-hour <br />storm event is 1.52 cfs and 0.17 acre-feet, respectively. The peak settleable concentration in the runoff from the <br />proposed Bleeder Shaft pad area is less than natural settleable solids concentrations for runoff from undisturbed lands, <br />given similar conditions. <br />The upgradient diversion ditches will be triangular ditches designed to safely divert the peak flow from the 10-year, 24- <br />hour storm with a minimum of 1-foot of freeboard and located as shown on Figure 1, Bleeder Shaft Pad SAE. The <br />shaft pad will be constructed such that it slopes toward the gravel filter. The check dam and grass filter efficiency was <br />modeled using the SEDCADTM4 check dam and grass filter utility. Exhibit 5 is submitted to demonstrate that <br />application of diversion ditches, drainage collection ditches, wattles, Ctitrlex blankets, and the sump, rock check dam, <br />and grass filter can effectively control and treat runoff from this area. <br />(51 Topsoil. A narrative exolainine the method of removal and the amount to be removed and the nlan for <br />storage of tonsoil. subsoil. and other material within the nernvt area subiect to requirements of the topsoil removal <br />perfomrance 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 fume of material to be <br />salvaged. A man of anv proposed storage structures shall accomnanv the narrative. The maps shall be prepared <br />accordine 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 haute-pad 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 Minine District Dewaterint= 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 />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 <br />will be windrowed to the side of the road and left in place. The 1,200 CY that will be salvaged from the road <br />extension will be placed in the stockpile that will be established on the fan pad. In addition to the topsoil stockpiled <br />from the road extension, approximately 740 CY will be salvaged and stockpiled from the pad. The soil resources <br />information was derived from information presented in Exhibits 7 and 8, Soil Profile Description and Soil Mapping <br />Unit Descriptions, Map No. 19, Mine No. 3, Soils presented in permit C-84-062. These materials are incorporated <br />herein by reference. At the bleeder fan site, Twentymile will establish a test pit to verify topsoil depths prior to <br />. salvaging topsoil. The stockpiled topsoil, which is located within the pad area, will be stabilized with the topsoil <br />stockpile stabilizing seed mixture. Prior to salvaging any topsoil from the site, a T & E species reconnaissance for <br />MROS-194 2.05-84.1 07/2/05 <br />