Resolution Revising the Amendment to the Water Quality Control Plan for the Santa Ana River Basin to Incorporate Organochlorine Compounds Total Maximum Daily

Resolution Revising the Amendment to the Water Quality Control Plan for the Santa Ana River Basin to Incorporate Organochlorine Compounds Total Maximum Daily

Loads (TMDLs) for San Diego Creek, Upper and Lower Newport Bay, Orange County, Californial, Adopted by Resolution No. R8-2007-0024 The Santa Ana Regional Water Quality Control Board (Regional Water Board) adopted an amendment to the Water Quality Control Plan for the Santa Ana River Basin (Basin Plan) to incorporate Organochlorine Compounds Total Maximum Daily Loads (TMDLs) for San Diego Creek, Upper Newport Bay and Lower Newport Bay on July 15, 2011. The State Water Resources Control Board (State Water Board) approved the Basin Plan Amendment on July 26, 2013 and the U.S. Environmental Protection Agency approved the amendment on November 12, 2013. Resolution No. R8-2011-0037 establishes TMLDs for 1,1,1-trichloro-2, 2-bis(p-chlorophenyl)ethane (DDT) and toxaphene in San Diego Creek and its tributaries; chlordane, DDT, and polychlorinated biphenyl (PCBs) in Upper Newport Bay; and, chlordane, DDT, and PCBs in Lower Newport Bay. The Basin Plan amendment also establishes informational TMDLs for chlordane and PCBs for San Diego Creek and its tributaries. TMDL allocations are assigned to urban, construction and roadway (Caltrans) discharges, commercial nurseries, agricultural discharges, open space discharges, streams and channels and undefined sources. The implementation plan for the TMDLs that is identified in the amendment addresses organochlorine compound impairment in the affected waters in an adaptive, phased manner, focusing on accelerating the natural attenuation of these compounds in the watershed through enhanced implementation of Best Management Practices (BMPs) by responsible parties to reduce the erosion and transport to surface waters of fine sediment to which the organochlorine compounds tend to adhere. Many of these BMPs are already in place as the result of existing permits issued by the Regional Water Board or State Water Board for storm water and construction activities, and/or in response to other establishes TMDLs. Monitoring and special investigation results will be used to consider refinements to both the BMPs and the TMDLs. Revisions to the TMDLs will be considered through the Basin Planning process. Compliance with sediment, water column and fish tissue targets that protect human health and aquatic habitat and attain Basin Plan water quality objectives is to be achieved as soon as possible, but no latter than Dec. 31, 2020.

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