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INFORMATION SHEET WASTE DISCHARGE REQUIREMENTS, ORDER NO. R5-2003-0017 VILLAGE WEST MARINA INVESTORS, PEGASUS GROUP GENERAL PARTNERS, CITY OF STOCKTON VILLAGE WEST MARINA MAINTENANCE DREDGING PROJECT SAN JOAQUIN COUNTY These Waste Discharge Requirements apply to maintenance dredging of the Village West Marina basin, adjacent to 14-mile Slough within the town of Stockton in San Joaquin County. The objective of the project is to remove 30 years of accumulated sediments and restore hazard-free boating and access to the marina. Maintenance dredging activities include dredging the Village West Marina basin, disposal of dredged sediments into a diked disposal site on land(Dredged Material Disposal site), discharges of effluent from the Dredged Material Disposal (DMD) site into surface water, and water quality monitoring during the dredging operation. The dredging operation will involve the use of a pipeline hydraulic suction dredge for maintaining needed depth for boating and marina access. The hydraulic dredging method greatly reduces the amount of turbidity within the water column. The Order only allows the use of a hydraulic suction dredge. Approximately 70,000 cubic yards of sediment will be removed from the marina basin, restoring the basin to its original design depth of—10 Mean Low Low Water. Following the completion of dredging operations, the Order will be rescinded. During excavation, a pipeline will transport the dredged material slurry to the DMD site for settling and disposal. The DMD site is a 50.5 acre former wastewater treatment basin owned by the City of Stockton. In the DMD site, solids will settle out and the "effluent'or"return water"will be pumped back into 14-Mile Slough. The DMD site is designed for a 96-hour holding time to remove a significant portion of suspended material from the effluent. The disposal site has a maximum dredge material capacity of 125,000 cubic yards. The DMD site will fully contain dredged material and prevent any surface runoff or erosion into waters of the state, except for the effluent discharge to 14-mile slough. The estimated rate of effluent discharge during the dredging operation will average 2.7 million gallons per day. After drying, the material may be removed for reuse at other locations. Dredging operations should be completed in approximately 3 weeks time. The Discharger has performed analytical analyses of sediments to be dredged in order to determine the anticipated sediment quality during dredging operations. The sediment constituents and average concentrations found in dredge material indicate water quality impacts will not occur at the marina dredging location or during the material disposal decant process. The Monitoring and Reporting Program includes monitoring during dredging at three locations: the dredge site, the effluent from the disposal site, and the receiving water. During dredging and disposal, the following constituents will be monitored: turbidity, dissolved oxygen, suspended solids,pH, flow, temperature, arsenic and tributyltin.