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Work Plan For Monitoring Well Installation-Fortner Unocal Station No. 0187 <br /> March 31, 1997 <br /> Task 1. Pre-Field Activities <br /> GSI will update the site safety plan. GSI will obtain an encroachment permit from the City of <br /> Stockton and a well installation permit from SJCPHS. Underground Service Alert (USA) will be <br /> notified a minimum of 48 hours prior to initiating well installation activities. <br /> Task 2. Field Activities <br /> GSI will install one off-site groundwater monitoring well at the location shown on Figure 3. Drilling <br /> and well installation will be performed by a California licensed well driller. The well boring will be <br /> drilled with eight-inch-diameter hollow-stem augers to a total depth of approximately 55 feet bgs. <br /> We estimate groundwater will be encountered at approximately 35 feet bgs, and propose to construct <br /> the well with 20 feet of screen within the saturated zone and 10 feet of screen extending above the <br /> saturated zone. The proposed well construction is shown on Figure 4. <br /> A G-R geologist will monitor the drilling activities and prepare a log of the boring. Soil samples for <br /> description and possible chemical analysis will be obtained from the well boring at five-foot intervals, <br /> as a minimum. Soil from each sampled interval will be screened in the field for the presence of <br /> volatile organic compounds using a photoionization detector (PID). Although the actual number of <br /> samples submitted for chemical analysis will depend on site conditions and field screening data, we <br /> anticipate a minimum of two unsaturated samples from the boring will be submitted for chemical <br /> analysis as described in Task 5. <br /> Drill cuttings will be stored at the site pending receipt of chemical analytical data and disposal. The <br /> drill cuttings will be stockpiled on and covered with plastic sheeting. Soil samples will be collected <br /> from the drill cuttings as described in Appendix A. These samples will be submitted to the laboratory <br /> for compositing into one sample, and then analyzed as described in Task 5. Steam cleaning rinsate <br /> waste water will be stored at the site in properly labelled drums pending disposal. <br /> Task 3. Wellhead survey. <br /> Following installation, GSI will have the well casing elevation surveyed to MSL by a California <br /> licensed surveyor. Horizontal coordinates of the well will also be obtained. <br /> Task 4. Well Development and Sampling. <br /> GSI will develop the newly installed well after being allowed to stand a minimum of 72 hours <br /> following completion. A groundwater sample will be collected from the well upon completion of <br /> development. Well development and sampling procedures are described in Appendix A. <br /> Groundwater removed from well during development will be stored at the site in properly labelled <br /> drums pending disposal. The newly installed groundwater monitoring well will be included in the <br /> quarterly monitoring and sampling program for the site. Groundwater samples will be analyzed as <br /> described in Task 5. <br /> 7827.21-1 3 <br />