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MANfiEPS ESfiNE0.5CChLATui15 The stainless steel sleeves containing samples for chemical analysis were capped with plastic caps The samples were placed in plastic bags and stored on ice at a temperature of ' approximately 4°C for transport to an analytical laboratory The remaining soil was described following the Unified Soil Classification System (USCS) under the direction of a California Registered Geologist A grab groundwater sample was collected with a Teflon bailer from inside the augers during the drilling of BH-13 The sample was sealed in a plastic bag and stored on ice at a temperature of approximately 4°C for transport to the analytical laboratory 1 After boring BH-13 was completed the borehole was backfilled with Lonestar 2116 sand from ' 65 ft to 44 ft bgs to prevent grout from intruding the aquifer and disrupting monitor well MW- 2A Bentonite chips were placed on top of the sand from 44 ft to 35 7 ft bgs After the ' bentonite hydrated, the borehole was backfilled to the surface with a bentonite/cement grout The concrete sidewalk was patched with concrete ' 2.1.3 Monitor Well Construction Monitor well MW-9 was constructed of 4-inch diameter Schedule 40 PVC casing A 20-foot section of 0 010-inch slotted PVC screen was installed from 55 ft to 35 ft bgs The screen extended approximately 3 ft above the water table A sand pack (Lonestar 2116) was placed from the bottom of the boring to 33 ft bgs A 3-foot bentonite seal was placed above the sand pack After the bentonite seal hydrated, the remaining annular space was grouted to the surface ' with a bentonite/cement grout A traffic grade flush mount utility box was installed over the monitor well A locking water tight cap was installed on the monitor well Appendix A ' contains the well log ' The monitor well was developed by pumping 60 gallons of groundwater from the well (approximately 6 5 well volumes) Prior to pumping, sediment present in the bottom of the well was removed with a bailer The top-of-casing elevation was surveyed relative to other wells at ' the site ' 2.1.4 Analytical Methods Soil samples were analyzed by EPA Method 8020 for benzene, toluene, ethylbenzene and total xylenes (BTEX), by EPA Method 8015M for total petroleum hydrocarbons-gasoline fraction 1 ' L W-wm ,.=WCxsA IST 5 0ct�r 19%