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<br />National King Coal, LLC <br />King II Mine <br />Colorado Mining Permit <br />#C-1981-035 <br />Technical Revision #TR-11 <br />Small Area Exemption #1: Preliminary Portal Excavation <br />National King Coal, LLC proposes to expose the seam outcrop at the King II mine portal bench <br />site for the purpose of gathering coal seam, roof and floor data in preparation for final <br />engineering design and construction of the portal bench area as approved in Permit Revision <br />PR-O8 of Colorado Mining Permit #C-1981-035. <br />This task would involve moving atrack-hoe type excavator to the known outcrop site on the <br />hillside as shown on the attached Map "King II-SAE #1 Preliminary Portal Excavation. It is <br />anticipated that the excavator will be able to access the site without the construction of a <br />road. In the event that a crude road would need to be constructed to access the site, the road <br />would follow the approved portal road alignment as shown on Map "King II-007B Sediment <br />Control Plan". All sediment control measures proposed for the portal site excavation will be <br />followed for any disturbed areas. <br />Sediment control measures will consist of a silt fence for retaining all sediment within the <br />disturbed area. Silt fence selection and installation will follow NRCS guidelines as shown on <br />the attached Colorado Fact Sheet. All topsoil and subsoil will be stockpiled separately and <br />protected from erosion. Mine development waste (earth which contains coal) will be removed <br />from the site and transported to the King Coal Mine (King I) refuse pile. Clean fill material will <br />be brought in as necessary to achieve Approximate Original Contour. Upon completion of data <br />collection activities, fill material will be returned to the "cut° and compacted in 12 inch lifts <br />using the bucket of the excavator: Likewise, subsoil and topsoil, respectively, will be returned <br />to the cut in 12 inch lifts and compacted using the bucket of the excavator. The area will be <br />re-seeded using the seed mix approved elsewhere in this plan. Surface runoff from the <br />disturbed area can be expected to be alkaline, with no generation of chemical leachates from <br />the small disturbed area. <br />It is estimated that the disturbed area at the portal excavation site will measure approximately <br />20 feet by 20 feet square. <br />Minimum sediment trapping capacity of a silt fence is calculated fora 20 ft X 20 ft disturbed <br />area fora 10 year, 24-hour storm event as follows: <br />Disturbed area = 20 ft X 20 ft = 400 ftz. <br />Assume 10-year storm erodes 0.1 ft of sediment (which equals soil loss of 233 tons per acre) <br />Total sediment eroded from 400 ftz disturbed area = 0.1 ft X 400 ft2 = 40 ft3. <br />Depth of sediment trapped along 25 ft-long silt fence = 40 ft3 / 25 ft long = 1.6 ft <br />Silt fence dimensions will allow for burying the bottom of the fence and tying back the ends. <br />National King Coal, LLC King II Mine <br />Small Area Exemption # 1, TR-11 Page 1 <br />Preliminary Portal Excavation September 20, 2006 <br />