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31 March 2008 AGE-NC Project No. 98-0500 Page 3 of 10 • SVE/IAS operation, monitoring/sampling and maintenance; • Report preparation. 2.1. PRE-FIELD WORK ACTIVITIES Upon CVRWQCB approval of this work plan, AGE will secure all relevant San Joaquin County Environmental Health Department(EHD)permit or regional permits and prepare an updated health and safety plan in accordance with Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities (National Institute for Occupational Safety and Health Administration, U.S. Coast Guard and U.S. Environmental Protection Agency, 1985). AGE will notify the CVRWQCB a minimum of 72 hours prior to commencement of any work. Prior to mobilization, the area of excavation will be clearly marked and an utility clearance obtained through Underground Service Alert. 2.2. INSTALLATION OF SVE REMEDIATION WELLS Based on TPH impacted-soil and highest concentration of all dissolved contaminants in ground water, determined on data collected during the on-going investigation, AGE proposes installation of deep, single completed SVE wells west of the dispenser area and east of the former dispenser area, to address the vadose zone contamination. Additionally to augment the in-situ air sparging ground water remediation technique,AGE proposes to installed additional IAS wells south,west and east of the former fuel dispenser island.The wells of significant benefit would be installed near wells MW-7 and MW-8,area which have the greatest dissolved hydrocarbon concentrations.The current operation of the SVE and IAS indicates the wells proposed would readily mitigated soil contamination within the vadose zone and treat shallow hydrocarbon ground water(Figure 3). Proposed SVE well locations are illustrated in Figure 4; well installation procedures are described in Section 3.2. The site stratigraphy requires the installation separate well screen, covering significantly differ stratigraphic unit, laterally across the site. The upper thirty feet of the site with a coarse grained unit and the depths between thirty-five feet bsg and the current water table (or fifty-five feet bsg). The proposed wells will be screened 35 to 55 feet bsg. These new wells, in conjunction with other SVEAAS wells,observation or monitoring wells will be utilized to monitor the mitigation of the site. Proposed wells will be installed at the following locations: • A SVE well will be located southeast of vapor well VW-14, near anew IAS well. • A SVE well will be located northeast of vapor well VW-14, near a well MW-48. Advanced GeoEnvironmental,Inc.