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1 <br /> was washed in a tri-sodium phosphate (TSP) solution and rinsed <br /> twice with water prior to each sampling run. <br /> 3.2 Well Completion <br /> MW-3 was completed using 20 feet of 0. 20 PVC slotted casing. With <br /> approval from Ms. Mary Meays of the PHS/EHD, MW-4 was completed <br /> with 25 feet of 0 . 20 PVC slotted casing. The monitoring well <br /> designs are shown in Appendix A. <br /> 3 . 3 Water Sampling <br />' The monitoring wells were surveyed relative to a benchmark with an <br /> assigned elevation of 100 feet. The depth to groundwater in MW-2 , <br /> MW-3 and MW-4 was measured on October 4 , 1993, to the nearest 0. 01 <br /> foot with a Solinist water level meter. After measurement of the <br /> I depth, a 4-inch Grundfos submersible pump was used to surge and <br /> purge the wells. Between 33 and 42 gallons of water (3 well <br /> volumes) were removed from each well to stabilize temperature, pH <br /> I and conductivity before collection of a water sample. Stabilization <br /> data were collected using Orion pH, conductivity and temperature <br /> meters. The purge water was placed in 55-gallon drums and stored <br /> on-site. Stabilization data are summarized in Table 1. <br /> A water sample was collected from each well using a new disposable <br /> plastic bailer. Each sample was collected in five 40-m1 EPA vials, <br />' placed in a chilled container and transported to a state-certified <br /> laboratory. <br /> I A water sample was also collected from the domestic well on the <br /> site (see Figure 2) . This sample was collected from the sampling <br /> port on the domestic well on October 12 , 1993 . The domestic well <br /> sample was collected in four 40-m1 EPA vials, placed in a chilled <br /> container and transported to a laboratory for analysis. <br /> 3 . 4 Laboratory Analysis <br /> Four soil samples from each monitoring well underwent laboratory <br /> analysis. Samples from depths of 30, 45, 75 and 85 feet from each <br /> well were analyzed by Alpha Analytical Laboratories (AAL) in Ukiah. <br /> The samples were analyzed for total petroleum hydrocarbons (TPH as <br /> gasoline) and volatile aromatics (BTE&X) in accordance with EPA <br /> methods 8015m and 80201 respectively. At the request of the <br /> PHS/EHD, the soil samples were also analyzed for volatile <br /> halocarbons in accordance with EPA method 8010. <br /> The monitoring well water samples were also transported to AAL and <br /> analyzed for TPH as gasoline, volatile aromatic compounds (BTE&X) , <br /> and halogenated organic compounds (HVOC ' s) ib accordance with EPA <br /> methods 8015, 602 , and 601, respectively. The domestic well sample <br /> was transported to Western Environmental Science and Technology <br /> (WEST) in Davis and analyzed for HVOC' s. <br /> 5 <br />