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prism. The surface water control plan for both the existing Forward and Austin Road Landfills consists of an integrated system of bench ditches, perimeter swales, and stormwater sedimentation basins. The final landfill is designed so surface water will run off the landfill via sheet flow until it is intercepted by a bench ditch. Bench ditches subsequently drain toward downdrains which discharge to perimeter channels. Finally, the perimeter channels drain to a sedimentation/detention basin. As required for a Classal,Iandfa e system for the future Forward Landfill has been designed to convey a peak discharge resulting from a>1,000-year, storm event. The final stormwater drainage control facilities based on this criteria are shown on Drawing 9 and supporting information is presented in Drawing 10, Hydrology Map and Appendix G. The drainage network for the completed landfill is designed to carry stormwater at velocities-that will intr ize ditch erosion. The operations manager monitors and inspects the condition and order of facilities, surfaces, and slopes as part of the daily operations. Surface drainage facilities, final soil cover areas, intermediate fill surfaces, and on-site access roads are observed routinely, and at least weekly during high-intensity rainfall periods. All necessary repairs are performed promptly. Temporary berms, straw mulch, or other erosion-control measures may be used to prevent erosion damage of soil covered areas when weather conditions inhibit complete repairs. All completed WMUs, cut and fill slopes, and portions of the landfill that will be exposed for more than 180 days will be covered to minimize erosion and downstream sedimentation. The effectiveness of the surface drainage control structures will be maintained by keeping drainage ditches clear of debris and excessive vegetation and by making repairs, as necessary, to correct the effects of physical damage, erosion, settlement, or other events detrimental to effective operation of the drainage control system. Corrective measures will be implemented if inspections reveal excessive erosion or damage to the drainage channels or if settlement causes ponding of runoff on the final cover. Eroded areas will require removal of the affected loose material followed by replacement and regrading of the area to match the adjacent surface contours. If ponding is observed in a channel over the final cover, the channel will be regraded to permit proper drainage of runoff. Inspections and maintenance of the drainage system will be carried out quarterly and after large precipitation events. Forward Landfill JTD 7-14 L:\Allied\2000.193\Reports\finaljtd:Sec-7.0:08/20/01 BRYAN A.STIRRAT 6 ASSOCIATES