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Draft Supplemental Environmental Impact Report Page IV.F-29 Forward Inc. Landfill 2018 Expansion Project Impact F.2.Potential"Take"of Chinook Salmon and Steelhead. Construction of the realigned channel and abandonment of the existing channel could result in the stranding of fish. In addition, if the relocated channel is opened up immediately prior to a significant rainfall event and/or a significant release of irrigation water, a sediment plume could attract Chinook salmon ' and/or steelhead from the San Joaquin River into the channel and cause potential mortality to the fish. This is a potentially significant impact. ' In the long term,restoration of the realigned creek channel would provide habitat for some semi-aquatic and riparian wildlife species,but is not expected to provide suitable habitat for salmonids due to low flows and the highly modified flow regime (pers. comm.Sydney Temple, ' Questa Engineering Corporation). Mitigation Measure F.2-1. To ensure that no aquatic vertebrates are stranded during abandonment of the existing South Branch of the South Fork of Littlejohn's Creek,the following measures shall be implemented: • Channel abandonment shall be restricted to the dry season(i.e.,between June 15 and October 15). • Channel abandonment shall occur only when the channel bottom has been dry for at least one week,that is, at least one week after the most recent release of water from ' Farmington Reservoir or any other sources. • Prior to initiation of any work within the abandoned channel (e.g., construction of coffer dams, filling, connecting to the realigned channel), a qualified biologist approved by the ' USFWS and CDFW shall inspect the entire length of the work area for any stranded aquatic vertebrates;any stranded aquatic vertebrates shall be captured and relocated to the nearest body of water in the same stream system. • Only a qualified biologist with all necessary federal and/or State permits may relocate fish and amphibians. Federally and State-listed species may only be relocated by biologist holding the appropriate federal or State permits. A record shall be maintained and submitted to the USFWS and CDFW of all fish and amphibians captured and relocated. • Any observed mortalities of species-status species shall be immediately reported to the USFWS and CDFW. Mitigation Measure F.2-2. Water shall be released into the restored South Branch of the South Fork of Littlejohn's Creek gradually to avoid creating a sediment plume downstream that could attract and cause mortality to Chinook salmon or steelhead from the San Joaquin River to enter the channel. After the relocation of the channel is completed and is ready to convey water, initial flows will be released at approximately 2 cubic feet/second (cfs), and shall be monitored to assure that water is released gradually through the channel for the first week after re- opening. This reduced flow would avoid causing a sediment plume. The restored channel shall not be opened prior to or during a significant rainfall event, and initial releases into the channel shall be coordinated with the Central San Joaquin Water Conservation District to ensure no significant releases are scheduled during the initial opening of the channel. Implementation of these mitigation measures would reduce salmon/steelhead impacts to a less than significant level because it would avoid causing a sediment plume.