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Consolidated Forward Inc. Landfill Page 13 site. The surface -water collection drain system will be designed to divert the water to the storm water collection basin in the southwest comer of the currem Austin Road Landfill, at times when enough surface water accumulates to have dischareed into the collection basin. All waste at the proposed Fonvard Landfill will be separated from the north and south branches of Littlejohns Creek by a levee system or other acceptable method designed to protect the site from a 100 -year flood event. The project includes channel reconfiguration and localized flood protection berms to isolate the landfill surfaces from floodwaters. The project design also includes provision of replacement floodplain area and storage volume in an easement along the relocated North Branch of the South For'< of South Littlejohns Creek. The channel and floodplain storage easement are designed to ac.-ommodate the 100 -year, 24- hour storm. The design also includes a three-foot freeboard. 45 (F.2) Proposed as Part of the Project: The JTD articulates the programs of drainage control structures and monitoring to inhibit erosion and sedimentation. Proposed structural controls include the drainage control system and daily cover. Operational controls include maintenance of the drainage system by keeping ditches clear of debris and excessive vegetation, and making ne-_-AYd repairs to drainage structures. Corrective measures will be implemented if inspections show excessive erosion or JMML damage to drainage channels. Eroded areas will be mitigated by removing loose debris Ipfollowed by replacement, regrading, and compacting the area. Monitoring and protection against sediment from entering the Littlejohns stream channel VWRI be implemented, including the diversion of part of Littlejohns Creek farther away from the landfilled area. In order to minimize sediment transport to the Littlejohns Creek landfill slopes, ridgetops, and peripheral areas will be revegetated to inhibit erosion. 46 (F.3) Proposed as Part of the Project: The liner and Jeachate collection system for the expansion sysu= -both over the top of the existing unlined Austin Road landfill and the extension of the existing leachate collection system at Forward— have been designed to meet or exceed the regulatory requirements as shown and discussed in the applicants JTD. The TI'D and the adequacy of the leachate collection system and associated monitoring are under review br- the RWQCB. The regulatory required separation between the liner and groundwater will be implemented to allow for chemicals in the leachate to attenuate before reaching the groundwater, should the leachate breach the collection system. The project design includes a leak detection system under the saps. The liner system will be overlain by a protective operations la•. cr consisting of a one -foot thickness of soil and a one -foot thick gravel layer that serves as the leachate collection layer. This t�vo-foot layer will serve to protect the liner system from slip or jagged materials in the waste.