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Draft Supplemental Environmental Impact Report Page III-36 Forward Inc.Landfill 2018 Expansion Project Relocate South Fork of South Littlejohns Creek To create a contiguous disposal area and optimize landfill airspace,an approximately 3,000-foot reach of the South Fork of South Littlejohn Creek would be relocated to a new 3,400-foot long reach to be constructed along the eastern and southern boundaries of the landfill(see Figures III.C- 4,III.0-5,and III.0-6).The existing creek traversing the landfill is generally a trapezoidal channel with 10-to 12-foot banks and a 10-to 15-foot bottom width. The channel measures, on average, 60 feet from bank top to bank top. This equates to a 4.13-acre creek zone. According to the wetland delineation 16 approximately 1.25 acres of jurisdictional wetlands exists within the existing channel. The existing creek performs relatively well in terms of flood control.17 The creek relocation is intended to: (1)provide adequate flood control(i.e.,to have capacity to carry the 100-year flow within its banks),and (2)provide a stable channel design that meets or exceeds the functions and values of the existing creek.Under the proposed relocation,the existing channel would be moved approximately 1,000 feet to the south to accommodate the further development of the Forward Landfill (see Figures III.0-4,III.0-5,and III.0-6). The relocated creek would be approximately 3,400 feet in length and would have greater flood control ability than the existing channel.The new channel would be approximately 50 to 60 feet wide. The proposed relocation would create 1.87 acres of USCOE jurisdictional areas that are inundated at a regular basis.18 To address Federal Aviation Administration(FAA)concerns regarding creation of bird habitat,riparian habitat is proposed to be restored and/or created offsite rather than being incorporated within the relocated creek channel. Potential offsite mitigation sites include Westervelt Environmental Services'Bullocks Bend Mitigation Bank and Wildlands' Fremont Landing Conservation Bank,both in Yolo County, and the National Fish and Wildlife Foundations Sacramento District California In-Lieu Fee Program. Constructing the channel would require moving approximately 40,000 cubic yards of material. The creek relocation would use design and construction techniques similar to those used in the successful relocation of the North Fork of South Littlejohns Creek in 2002.Litter control in the relocated creek would follow established litter control practices at the site. A combination of monitored litter fences,screening,and litter pickers would be used. A new two-lane bridge("South Bridge')would cross the relocated creek from Austin Road, consisting of a clear span with engineered concrete footings located in the creek embankment. The bridge would be a concrete slab bridge or similar type construction. The bridge would be approximately 63 feet long by 28 feet wide, and allow for two twelve-foot-wide lanes with a two-foot shoulder. There would be one foot of freeboard between the 100-year water surface and the bridge soffit. 16 Monk&Associates,Environmental Consultants,Letter report to William H. Guthrie, U.S. Army Corps of Engineers, Sacramento District,June 22,2018(Monk&Associates,2018) 1'Project Description for Land Use Permit Application,Forward Landfill(Bryan A.Stirrat&Associates,2008). 18 Concept Design Report, South Branch of the South Fork ofLittle John Creek Relocation Project(Questa Engineering Corp,2017)