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V � <br /> - 2.2.2 Groundwater Grab Sampling <br /> At the top of the groundwater-bearing zone in each of the sample locations, a push driven <br /> groundwater sampling device consisting of a steel inner core well screen nested inside a steel <br /> outer sampler sheath will be advanced an additional two feet into the formation. When the <br /> .� desired depth is reached, the sampler will be pulled up approximately four feet to expose the <br /> open borehole to the inner core well screen. From this temporary well, a groundwater grab <br /> w <br /> sample will be collected by lowering a polyethylene tubing and check valve system down the <br /> hollow center of the drilling rod and into the groundwater column. Groundwater will be pumped <br /> to the surface using an oscillating motion. <br /> V <br /> 2.2.3 Borehole Abandonment <br /> w <br /> Each of the push-point soil borings will be abandoned by filling them with a cement/bentonite <br /> grout. The grout will be pumped from the surface to the bottom of the hole using a grout pump <br /> �- and tremie tube system. Any surface pavement will be restored to its existing condition. <br /> 2.2.4 Laboratory Analyses of Soil and Groundwater Grab Samples <br /> All soil and groundwater grab samples will be contained, labeled, packaged and stored in an <br /> iced cooler for transport under chain-of-custody documentation to a state of California <br /> Department of Health Services certified analytical laboratory. <br /> +•r <br /> From SB-6 (southwest corner of UST excavation), the soil samples collected from 20, 25, 30, <br /> 35-feet bgs and the capillary fringe (i.e., zone of groundwater fluctuation) will be submitted for <br /> laboratory analysis. Each of these soil samples will be analyzed for TPH-as-diesel, TPH-as- <br /> gasoline, benzene, toluene, ethylbenzene, xylenes (BTEX) and methyl tertiary butyl ether <br /> (MTBE) by modified EPA Method 8015/8020. The soil samples from 20-feet bgs and from the <br /> y <br /> capillary fringe will also be analyzed for volatile organic compounds including the alcohol and <br /> ether oxygenate compounds methanol, ethanol, tertiary butanol, MTBE, di-isopropyl ether <br /> �--► (DIPE), ethyl tertiary butyl ether(ETBE) and tertiary amyl methyl ether(TAME) by EPA Method <br /> 8260. <br /> From SB-7 (remote fill location), the soil samples collected from 5, 10, 15-feet and the capillary <br /> fringe will be submitted for laboratory analysis. Each of these soil samples will be analyzed for <br /> TPH-as-diesel, TPH-as-gasoline, BTEX and MTBE by modified EPA Method 8015/8020. In <br /> addition, the soil samples collected from 5-feet bgs and from the capillary fringe will be analyzed <br /> for volatile organic compounds including the oxygenate compounds by EPA Method 8260. <br /> 5 <br />