ARCHIVED REPORTS_DRAFT ENVIRONMENTAL IMPACT REPORT

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at the City's existing Crossroads Business Park facility and 0.16 mgd of wastewater is treated at the City's WRP-1 MBR facility(Gibson,pers. comm., 2007). At buildout,the City of Lathrop is projected to generate approximately 11.5 mgd of wastewater. The main component of the City's integrated wastewater disposal strategy is to maximize use of recycled water on 1,022 acres of irrigated land within the City. Once the recycled water demand is met,the City plans to maximize the use of its allocated capacity at the Manteca WQCF. At build out,the City would discharge up to 2.2 mgd to the Manteca WQCF,if capacity is available. Lastly,when the recycled water demand and the Manteca WQCF allocation have been met,the City plans to discharge the remaining treated effluent to the San Joaquin River. The project includes a tertiary treatment system, including nitrification-denitrification, coagulation, filtration, and ultraviolet light disinfection. Treated effluent would be discharged to the San Joaquin River through a high rate diffuser system that would rapidly mix the effluent with river water. The newly expanded WRP-1 plant is designed to treat approximately 0.75 million gallons per day of raw sewage. The treated effluent(i.e.,recycled water)meets Title 22 standards for reuse and is used for a variety of purposes including landscape irrigation and farming activities for fodder crops. The new expansion includes advanced membrane bio-reactor(MBR)technology to produce high quality recycled water to be used to irrigate landscaping, schools, and parks and to grow crops on designated land application areas.A new recycled-water system consisting of storage ponds,pump stations, and a distribution system is currently being constructed as part of a WRP-1 expansion project. CITY OF STOCKTON REGIONAL WASTEWATER CONTROL FACILITY EXPANSION The City of Stockton Regional Wastewater Control Facility(RWCF)is located in the southern portion of Stockton. The plant is owned and operated by the City of Stockton and provides tertiary treatment prior to effluent discharge to the San Joaquin River. The San Joaquin River bisects the plant site. In general,the preliminary, primary, a portion of the secondary and the solids handling facilities are located east of the river,while the remaining secondary facilities and the tertiary facilities are located west of the river. Although the current dry weather design flow of the secondary plant is 38 mgd,the City optimizes the operation of the tertiary plant,which allows a permitted discharge flow of 55 mgd(Burrell,pers. comm.,2007). The City is in process of a six-stage plant expansion program for its RWCF. Stages one and two were expected to be completed in 2003. Planning was initiated for stages three through six;however,the master planning process and environmental compliance were put on hold while the City makes a decision regarding privatization of their operation and maintenance of its municipal utilities. Privatization of the facilities was approved in early 2003. DELTA WETLANDS PROJECT The Delta Wetlands Project(DW) involves diverting and storing water on two Sacramento—San Joaquin Delta islands(Bacon Island and Webb Tract,termed"reservoir islands") for later discharge for export sales or to meet outflow requirements for the San Francisco Bay/Sacramento San Joaquin Delta estuary. During periods when the reservoir islands are not being used to store water, shallow water would be managed within an inner levee system on the reservoir. The project also involves seasonally diverting water to create and enhance wetlands and to manage wildlife habitat on two Delta islands(Bouldin Island and Holland Tract,referred to as "habitat islands"). These islands would be operated to support wetlands and wildlife habitat.Additionally,recreation facilities would be constructed along the perimeter levees on all four DW islands. To operate the project,DW would improve and strengthen levees on the four islands and install additional siphons and water pumps on the perimeters of the reservoir islands. The initial water storage capacity of the reservoir islands would be 238,000 acre-feet(AF) and increase to 260,000AF in 50 years due to soil subsidence. The mean annual diversion and discharge is estimated to be 222,000-225,000 AF and 180,000-202,000 AF,respectively. Both reservoir islands could be filled and emptied in EDAW Manteca WQCF and Collection System Master Plans EIR Cumulative Impacts 5-6 City of Manteca