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-18- <br /> Coal Processing Waste Enbankment Sediment Control <br /> A system of two sediment ponds is planned to be constructed for the five-year <br /> coal processing waste disposal area. These ponds will treat the drainage from <br /> an area of 15.3 acres. The two ponds are designed to have a combined storage <br /> capacity of 3.46 acre-feet of which 1 .1 acre-feet is for storage of sediment <br /> from the drainage area. 0.60 acre-feet is for storage of runoff, and 1 .76 <br /> acre-feet is excess storage. The drainage ditches leading to the sediment <br /> ponds are equipped with turnout gates so either pond can accept the runoff <br /> from the drainage area or both ponds can receive the drainage. Both ponds are <br /> designed to have 24 inch cmp principal spillways with gated orifice holes <br /> located at the maximum sediment storage elevation plus an incised emergency <br /> spillway capable of passing the 25-year, 24-hour peak flow. <br /> The applicant's sediment control plan does not include any sediment control <br /> for the topsoil stockpile. Therefore, the following stipulation is necessary: <br /> Stipulation No. 12 <br /> THE PERMITTEE IS DIRECTED TO CONSTRUCT A BERM AT LEAST THREE FEET IN <br /> HEIGHT AROUND THE LOWER ENO OF THE TOPSOIL STOCKPILE PRIOR TO <br /> CONSTRUCTION OF THE PILE. THIS BERM MUST BE PLACED A MINIMUM OF <br /> 15 FEET FROM THE TOE OF THE TOPSOIL STOCKPILE. THE TOPSOIL STOCKPILE <br /> MUST BE IMMEDIATELY SEEDED AND MULCHED UPON COMPLETION OF TOPSOIL <br /> STRIPPING IN THE FIVE-YEAR REFUSE DISPOSAL AREA. <br /> A general plan for the coal processing waste embankment during years 6-40 was <br /> submitted. This general plan shows that one additional sediment pond will be <br /> constructed during the life of the pile. <br /> Small Area Exemptions <br /> In addition to the southwest corner of the Mine No. 4 pad, which was discussed <br /> previously, the applicant has requested small area exemptions from <br /> constructing sediment ponds on: 1) The Mine No. 3 middle coal storage bin pad <br /> (0.08 acres), 2) The Mine No. 4 lower coal storage bin pad (0.44 acres) , and <br /> 3) Mine No. 1 powder magazine, Mine No. 4 powder magazine, and the Rock Tunnel <br /> powder magazine (all less than 0.1 acres). These areas are small and there is <br /> no mixture of surface drainage from surface area. In addition, these areas <br /> are graveled and some portions are planned to be revegetated. Therefore, <br /> based upon the above discussion and pursuant to Rule 4.05.2(3), the Division <br /> hereby grants small area exemptions from construction of sediment ponds on the <br /> aforementioned areas. <br /> Stream Channel Reconstruction <br /> The applicant has reconstructed one portion of the Dutch Creek Channel . <br /> The portion of the Dutch Creek channel which has been reconstructed, is <br /> approximately 600 feet in length directly above the confluence of Dutch Creek <br /> and Coal Creek. The reconstructed channel is trapezoidal in shape and <br /> concrete lined. In discussions with the applicant, it was determined that the <br /> reconstructed channel will be a permanent feature. The applicant originally <br /> provided no information on the sizing of the reconstructed channel in the <br /> original submission. However, the applicant subsequently submitted a plan to <br /> prove that the reconstructed channel is in compliance with Rule 4.05.4(2)(b) . <br />