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an air sparging and soil vapor extraction (AS/SVE) system. The system consisted of two sets of <br /> ( AS/SVE wells and two sets of nested piezometers. The system was shut down in November <br /> 1995,when rising groundwater levels submerged the SVE wells. An estimated 8,787 pounds of <br /> I TPH-gasoline were removed during the period of system operation,however,as indicated by <br /> the quarterly monitoring results at the site,elevated concentrations of gasoline constituents are <br /> still present in groundwater in the former tank and pump area. <br /> SECTION 3 <br /> ' Sampling Methodologies and Analytical Plan <br /> This section presents the sampling methodologies and techniques to be followed in conducting <br /> this focused field investigation. The sample analytical plan is also presented. <br /> 3.1 Sampling Methodologies <br /> 3.1.1 Cone Penetrometer Testing (CPT) <br /> All borings installed during this field investigation will be installed using a CPT drill rig. CPT <br /> lithologic logging will be conducted using a standard electronic piezocone (CPTU).CPTU <br /> measurements of cone bearing,sleeve friction,and dynamic pore water pressure will be <br /> recorded at 5 cm intervals for the entire length of each boring. An ultra-violet induced <br /> fluorescence (UVIF) module will be used in addition to the CPTU to log the borings installed <br /> in the former tank and pump area. The UVIF module detects the presence of petroleum <br /> hydrocarbons in soil and groundwater and will be used as a screening tool to provide <br /> information about the vertical distribution of petroleum hydrocarbons. <br /> CPT borings will be installed at 7 locations on the Disco site.Five borings will be installed <br /> upgradient,downgradient, and within the former tank and pump area, and 2 borings will be <br /> installed downgradient of the site as shown in Figure 2. The downgradient borings will be <br /> installed in the shoulder area of Highway 4,approximately 140 feet downgradient from the <br /> former tank and pump area. CPT logs will be obtained in each of the borings to a depth of <br /> approximately 150 feet,if possible. If refusal is met during CPT logging prior to attaining the <br /> target depth,one additional attempt will be made at each location by moving.a short distance <br /> from the original location and making one more attempt. If the second attempt fails,CPT <br /> logging in that location will be abandoned. <br /> Prior to beginning field work,boring permit applications will be submitted to PHS for <br /> approval,all boring locations will be marked and Underground Service Alert(USA)will be <br /> notified,and approval from Cal Trans for work in the shoulder area of Highway 4 will be <br /> obtained. <br /> 3.1.2 Soil and Grab Groundwater Sampling <br /> P 9 <br /> Adjacent to each of the seven CPT borings,additional borings will be installed to obtain soil <br /> and grab groundwater samples.These borings will be completed using direct push methods <br /> that are compatible with the CPT sampling rig,as described below. The exact sampling depths <br /> will be determined in the field by the onsite field geologist based on the CPT lithologic and <br /> UVIF logs. <br /> SFO/CABERNEdGR0UP5/EBGIDELMONTFIPLANT_33ANORKPLAN GPT.000 4 <br />