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I � for volatile compounds using an Organic Vapor Meter (OVM) The soil was screened by emptying soil from one of the sample tubes into a plastic bag The bag was then sealed and placed in the sun for approximately 10 minutes After the VOCs were allowed to volatilize, the OVM measured the vapor in the bag through a small hole punched in the bag OVM readings are used as a screening tool only, since the procedures are not as rigorous as those used in the laboratory OVM readings can be found on ' the boring logs presented in Appendix B ' 4 2 2 Air Sparge Well Construction and Development The well was constructed within the hollow stem augers using 2-inch ' diameter flush-threaded, schedule 40, 0 020-inch slotted PVC well screen and blank casing The well was screened between 16 and 17-feet bgs to allow for the infection of air at the ver) bottom of the water-bearing zone ' The reason for the very short screened interval was to provide for sparging the maximum possible aquifer thickness since this is a very thin water bearing zone ' The well casing was lowered through the augers and #2112 filter pack sand was placed in the annular space between the well casing and the borehole from the bottom of the boring to 0 5-feet above the screened interval Prior to placing the sanitary seal, the well was developed using ' surge block agitation and evacuation with a bailer Once the sandpack was settled and there was a significant reduction in the amount of fine sediment in the purged water, 1-foot of bentonite pellets were placed on top of the sand pack The bentonite was hydrated with water prior to placing the cement sanitary seal Cement mixed with 3 to 5 percent bentonite powder by volume was used to fill the annular space between the bentonite layer and the surface to prevent surface water from infiltrating into the well The well head is protected with a locking well plug beneath an at-grade, traffic-rated well box 4 .3 Soil Samnle Analysis The soil sample collected from 11 5-feet bgs in boring EW-1 was analyzed by Kiff Analytical, LLCof Davis, California (ELAP #2236) for TPH-G, BTEX, ' oxygenates and HVOCs by EPA Method 8260 This sample was selected since it represented soil that appeared to have the highest hydrocarbon ' concentrations based on field indications such as odor, staining and OVM readings, as well as representing the capillary zone This analysis was performed to provide a pie-remediation baseline for this location The soil sample contained 220 ppm TPH-G, 150 ppm TPH-D, 0 26 ppm toluene, Frank's One Stop Interim Remediation System Workplan — September 2000