Laserfiche WebLink
' struction, the berm will be continued to the nearest point of exit <br /> from the site. For Modules 7 through 11 , the perimeter berm will also <br /> ' be constructed one module ahead of the fill module. When construction <br /> of the perimeter berm interferes with any major natural drainage <br /> ' channels entering the site, the remainder of the perimeter berm will <br /> be constructed and joined with the berm adjacent to Module 1 . <br /> The discharge of sediment-laden runoff will be controlled by silt <br /> ' fences during the excavation, preparation, and operation phases. The <br /> silt fences will be constructed parallel to all drainage ditches and <br /> swales to control sediment at the source and limit the volume of flow <br /> ' passing through any one section of fence. A series of straw-bale <br /> dikes will be constructed approximately every 150 feet along the down- <br /> gradient silt fences to limit downgradient flow of sediment-laden wa- <br /> ter. <br /> ' Final cover and vegetation will be placed as soon as possible after <br /> ' each module is brought to final grade. Vegetative growth will reduce <br /> sheet flow run-off, limiting erosion and movement of sediment. <br /> ' 4.5 LEACHATE CONTROL <br /> ' In some areas of the United States, where precipitation is high or <br /> when cover on landfills is poor, rain may infiltrate through the land- <br /> fill cover soil and percolate into the waste fill . Leachate is pro- <br /> duced when the infiltration of water into the landfill exceeds the <br /> ' moisture-holding capacity of the wastes. When the absorptive capacity <br /> of the refuse is exceeded, leachate (water containing soluble sub- <br /> stances) is generated. <br /> 1 <br /> To evaluate leachate produced when precipitation infiltrates into <br /> ' landfills, the U.S. Environmental Protection Agency (EPA) uses the <br /> water-balance method developed by C.W. Thornthwaite. This method is <br /> ' based on the relationship between precipitation, surface runoff, evap- <br /> otranspiration, and soil -moisture storage. Using this method, the <br /> ' PJ9 9390209A.00D 16 <br /> ' EM(o11 Associates <br />