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-52- The Division finds that the roads are in compliance with the Regulations. Ponds, Impoundments, and Diversions The drainage and sediment control system at the mine and loadout were reviewed for compliance with Rules 2.05.3(4) and 4.05. This information is briefly described on pages 27-40 and pages 48-50 of Rule 2.05. Substantial design detail can be found in Volumes 8 and 8A, Sheet 6 of the OVWM design specifications, Volume 6, Map 6A-2C of the Waste Disposal Appendix and Map 6A-5D of the Reclaimed Configuration Appendix. CWI constructed a clean water diversion above the main mine site to protect the lower elevation fills. This diversion ditch experienced a slide. Following several stability evaluations N olume 6), CWI buttressed the toe of the slide and built an ancillary ditch along the south side of the cut to ensure capacity for water flow during a 100-year, 24-hour event. Annual maintenance is performed on the original ditch. The Division approves this structure as designed. Three variances were granted from the requirements of Rule 4.05.2 in accordance with Rule 4.05.2(3). The variance grants an exemption from passing disturbed drainage through a sediment pond prior to discharge. One "small area exemption" was granted for the fan level bench and explosives area above the portal area. This area contains an intake airshaft, fan, and topsoil stockpile. Since the site was small, level, experiences only minor use, and has been reseeded, the variance was granted. Construction of a pond on this bench would be difficult because of the small area involved. A small area exemption was also granted accordance with Rule 4.05.2(3) for the fill outslopes at the new West Mine Portal Benches. The operator has demonstrated that construction of a sediment pond to control drainage from these areas during construction and mine operation is infeasible. Alternative sediment controls, including proper sequencing of topsoil salvage and placement during construction, immediate seeding and mulching of the topsoiled fill outslopes, placing erosion control netting over the mulched outslopes, and the placement of erosion control mats and silt fencing in strategic locations, was implemented during the construction and operation phase to control runoff from these areas, which total 3.3 acres. A monitoring program used to ensure that site discharge effluent limitations will be met and that surface erosion will be kept at a minimum. During the reclamation phase sediment control soil dikes and other necessary ponding structures were installed to control runoff. A third small area exemption was granted fora bench holding a water storage tank and ventilation shaft north of the OVWM portal. The total disturbed area covers less than one acre. CWI installed silt fences to control off-site sedimentation.