Laserfiche WebLink
WASTE DISCHARGE REQUIREMENTS <br /> DEFENSE DISTRIBUTION REGION WEST TRACY <br /> SAN JOAQUIN COUNTY <br /> data necessary to evaluate the system's effectiveness and its potential application to other <br /> areas on the Depot as part of the site's final remedial action. <br /> 13. The main components of the Dischargers' full scale groundwater cleanup system include <br /> the following: <br /> a. Extraction wells in three different areas. The extraction wells will be screened <br /> within the uppermost sand and gravel aquifer, north and northeast of DDRW main <br /> facility. Extraction of approximately 1250 gpm (1.8 MGD) of contaminated ground <br /> water will be made from three different areas. <br /> b. Two separate air stripping facilities to treat the extracted contaminated ground <br /> water. Each air stripping tower's hydraulic design capacity is approximately 500 gpm. <br /> The system has been designed, based on use of best practicable treatment or control <br /> method (BPT), to achieve monthly median discharge limits for TCE and PCE of 0.5 <br /> µg/1. A vapor control unit, utilizing granulated activated carbon, will be used to <br /> remove trace organics from the tower's exhaust air. <br /> c. Shallow aquifer reinjection wells and infiltration galleries for the disposal of the <br /> treated ground water. Treated groundwater may also be discharged for disposal to <br /> the existing storm water evaporation/percolation pond during the summer months (May <br /> through October). Provided the Discharger maintains adequate volume in the storm <br /> water pond for storm events, discharge to the storm water pond will be allowed year- <br /> round. <br /> 14. The existing storm water evaporation/percolation pond collects storm water runoff at <br /> DDRW Tracy. Storm water runoff to this storm water pond is currently being monitored <br /> pursuant to Waste Discharge Requirements Order No. 89-209 issued to regulate waste water <br /> disposal from the sanitary sewer system. <br /> 15. The beneficial uses of the ground water are domestic, municipal, industrial, and agricultural <br /> supply. <br /> 16. The Board adopted a Water Quality Control Plan for the Sacramento and San Joaquin River <br /> Basins, Third Edition, which contains water quality objectives for all waters of the Basin. <br /> These requirements are consistent with that Plan. <br /> 17. The Discharger is required to protect the environment to the greatest degree possible (Public <br /> Resources Code, Section 21000, et seq.). <br />