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UST. Groundwater samples collected after well installation were reported to contain TPH-G up to 52,000 micrograms per liter(ltg/L). No additional subsurface investigation work has been conducted at the site since 1997.The following scope of work has been prepared from discussions during our meeting with the CVRWQCB and from available site data to move the site towards site closure consideration. 2.0 PROPOSED TASKS Winzler&Kelly proposes to install three groundwater monitoring wells and two soil gas monitoring points with up to six soil samples collected from each monitoring well boring for analytical purposes, in order to define the vertical and horizontal extent of petroleum hydrocarbon impacted soil. The top of casing elevation for the new groundwater monitoring wells at the site will be surveyed relative to mean sea level. The horizontal location of the new monitoring wells will also be surveyed with high precision utilizing global positioning system equipment. The attached Figure 2 shows the locations of the proposed soil borings/monitoring wells. Also included in the scope is a 2,000-foot radius sensitive receptor survey and four quarters of groundwater monitoring and sampling. 2.1 PRE-FIELD ACTIVITIES Prior to initiating the drilling and sampling activities, each proposed boring location will be marked with white paint and Underground Services Alert(USA)will be notified at least 48 hours before the field event, in order to clear subsurface utilities. A private underground locating company will also be hired to clear each drilling location. A soil boring and well construction permit be obtained from the San Joaquin County Environmental Health Department(SJCEHD).Additionally, he SJCEHD and the CVRWQCB will be notified of the proposed field activities at least five days in advance. 2.2 DRILLING AND MONITORING WELL CONSTRUCTION ACTIVITIES Drilling will be performed utilizing a truck mounted hollow-stem auger drill rig. The three soil borings slated to become monitoring wells will be sampled every 5 feet utilizing a California split spoon sampler. Drilling and sampling equipment will be decontaminated before and after each use using a steam cleaner. Soil cuttings and decontamination rinsate will be stored in properly labeled Department of Transportation approved 55-gallon steel drums,pending evaluation of disposal options. The three monitoring wells are proposed to be drilled to a depth of approximately 50 feet bgs, dependent on where depth-to-groundwater is encountered. Each well will be constructed using 2-inch diameter polyvinyl chloride (PVC) casing with a 20-foot long section of 0.020-inch factory slotted screen extending from a depth of approximately 30 to 50 feet bgs in each well (or 5 feet above and 15 feet below the groundwater surface).The well annulus will be packed with#2/12 or equivalent sized Lonestar sand from the total depth of the boring to at least 6 inches above the screened interval,followed by 2.0 feet of hydrated bentonite chips and a neat cement sanitary seal to within 6 inches of the ground surface. The surface of each well will be completed with a traffic- 2 W INZLER&KELLY 03009-10017-37020 August 2011