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depth of approximately 150 feet bgs,if possible.If refusal is met during CPT logging prior to attaining the ( target depth,one additional attempt will be made at each location by moving a short distance from the original location and making one more attempt.If the second attempt fails,CPT logging in that location will be abandoned. Prior to beginning field work,boring and well permit applications will be submitted to PHS for approval. All boring locations will be marked and Underground Service Alert(USA)will be notified,and approval from Cal Trans and the City of Stockton will be obtained for work on Caltrans and City of Stockton property. 3.1.2 Grab Groundwater Sampling Adjacent to each of the seven CPT borings,additional borings will be installed to obtain grab groundwater samples. These borings will be completed using direct push methods that are compatible with the CPT sampling rig,as described below.The exact sampling depths will be determined in the field by the onsite field geologist based on the CPT lithologic logs. I Groundwater Samples Grab groundwater samples will be collected from seven boring locations using a Hydropunch'sampler or equivalent sampling equipment. Upon reaching the appropriate depth for sampling,the sampling device will be lowered to the bottom of the boring and advanced an additional 4 to 5 feet into the undisturbed portion of the aquifer. Groundwater samples will be extracted from the sampling device using a small diameter bailer and transferred to appropriate sample containers.Sample bottles to be analyzed for volatile organic compounds will be filled so that no air bubbles are present within the bottle. All relevant information (e.g.,boring designation,volume of water extracted,time of sampling)will be recorded in a field i notebook. Groundwater samples will be collected at each significantly different lithologic unit encountered vertically. Groundwater sampling is expected to focus on the sandy zone present at approximately 100 feet bgs. E All groundwater samples will be analyzed for TPH-gas and BTEX by EPA Method 8015/8020,and oxygenates,including 1,2-Dichloroethane (1,2-DCA), 1,2-Dibromoethane (EDB),and tert Butanol (TBA) by EPA Method 8260,in a state-certified laboratory. All samples will be shipped to a California-certified laboratory using chain-of-custody procedures for analysis. Upon completion of the grab groundwater sampling,the boring will be abandoned by backfilling with a cement grout tremied into the boring through one-inch diameter PVC tremie pipe. 3.2 Well Installation The following discussion details the procedures for the installation of monitoring wells and one extraction well. All wells will be installed on Del Monte property,City of Stockton public right-of-way,and/or CalTrans property. 3.2.1 Monitoring Well Installation Four monitoring wells will be installed to a depth of approximately 100 ft bgs,and one deep monitoring ( well will be installed to approximately 150 ft bgs at the locations shown in Figure 2. The actual number and locations of monitoring wells will be assessed after receiving the results of the CPT grab groundwater i CATEMPNORKauw_DCAJ.DOC g