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1 <br /> • indicate that gasoline range hydrocarbons g y bons are found between the 30 <br /> and 40 foot depths southeast of the excavation. Soil samples <br /> taken from the base of the three pump island excavations, <br /> indicated that contaminated soil remains beneath the eastern and <br /> western pump island areas at the 20 foot depth, see Figures 3B, 3C <br /> and Table 1. <br /> To remediate the aged gasoline range contaminated soil beneath the <br /> pump island area and the area southeast of the tank excavation, <br /> three vapor recovery wells will be installed using Hogate Drilling <br /> Co's B--40L Mobile Drill and 10" hollow steam augers. Borings will <br /> be advanced to the 35 - 40 foot depth under the direct supervision <br /> of a NEGE geologist. Soil samples will be obtained every 5 feet <br /> once into native soil, beneath the excavation back fill. All <br /> cuttings and sampler will be screened with a photoionizing <br /> detector (PID) , with selected samples being preserved, chain of <br /> custody hand delivered to Chemtech Laboratories for analysis. <br /> SOIL AND GROUND WATER SAMPLING PROCEDURES <br /> All samples were obtained by a qualified geologist working <br /> directly under the supervision of California Registered Geologist <br /> #3037. The samples were collected, preserved, labeled and chain <br /> of custody hand delivered to ChemTech Analytical Laboratories, <br /> 30 .7 Kilgore Road #210, Rancho Cordova, CA 95742 (916-635--3952) . <br /> ChemTech is a State of California certified lab (#359) . All <br /> samples obtained from the borings for the monitor wells were <br /> analyzed using the following EPA and DOHS methods: 5030 for <br /> extraction, 8015-TPH, and 8020/602-BTEX. Since initial sampling <br /> showed that TEL and EDB did not exist at this site these analyses <br /> were not carried out for this sampling. <br /> Prior to obtaining a ground water sample from each monitor well, a <br /> water interface probe was lowered into each well to obtain a depth <br /> to ground water measurement. Then the wells were purged <br /> (approximately 5 gallons) until temperature, pH, and conduct-vity <br /> stabilized, indicating that fresh ground water would be sampled. <br /> A dedicated sterile disposable PVC bailer was then lowered into <br /> the well to collect the ground water sample. The ground water was <br /> then slowly decanted into EPA series 200 clean glass sample <br /> containers (4-40 ml VOA vials per well) . The sample containers <br /> were then labeled (site designation, well number, date, time <br /> sampled and analysis) , sealed in zip lock baggies, placed in a <br /> cooler with ice and cooled to 4-C. The samples were then chain of <br /> custody, hand delivered to the laboratory performing the analysis <br /> (Chemtech) . <br /> Soil samples were obtained from the excavations by hand augering a <br /> 6" diameter hole six inches below the base of the excavation, then <br /> obtaining the sample by hand driving a 2"x6" sterile brass sleeve <br /> that had been inserted into a barrel sampler attached to rod <br /> extensions and a slam bar. The auger and sampler were cleaned <br /> -✓ with trisodium phosphate and clean water rinse, prior to and <br />