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04 January 2013 AGE -NC Project No. 12-2179 Page 7 of 7 depth) but wide (3 feet at the bottom) drainage ditch around the eastern perimeter of the landfill that will direct all collected surface water toward the area south of the existing landfill where a previously located collection area has been planned. In order to direct collected surface water from the landfill cover, via gravity to this collection area, the perimeter drainage ditch will be located partially up the side slope at the north end, gradually moving down the slope as the ditch elevation drops. In addition, a perimeter berm will prevent potential flooding of the adjacent land surface around the landfill by containing flow from the bottom portion of the side slope areas. Infiltration of collected surface water from the majority of the final cover (as directed by the perimeter drainage ditch) will naturally occur within the collection area to the south. The perimeter ditch will be constructed, when reducing the existing side slopes, by shaping the ditch cross-section into the native soil materials within the reduced 5:1 side slopes. This raised ditch is being constructed in order to avoid any excavation of soils around the perimeter of the landfill where debris has previously been identified. However, prior to complete establishment of the vegetative cover, preferential pathways may be created down the slopes during significant rain events that might result in unintended channels on the completed side slopes. As the locations of these channels will be self -determined during the initial storm events after completion of the final site grading, the design will allow for the construction of engineered channels after completion of the cover system construction (but not as part of the initial construction). The cover will need to be maintained until establishment of the vegetative cover is complete. Rip -Rap channels may be required where preferential pathways begin to appear following major storm events. These field -located channels would be constructed of 12 inches of appropriately sized rip -rap, replacing the upper layers of 6 inches of topsoil and 6 inches of common fill. Advanced GeoEnvironmental, Inc.