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1 <br /> After the collection of depth measurements, a submersible pump was used to purge <br /> ` between 4 and 7 gallons of water (minimum of 3 well volumes) from MW-2, MW-3, ASO-1, <br /> ASO-2 and ASO-3 to stabilize pH, temperature and conductivity Stabilization parameters <br /> were measured at 1-gallon intervals using an ICNI water analyzer Purge water aas placed <br /> in DOT drums Stabilization data sheets are included in Appendix C <br /> After stabilization, a sample was collected from each purged well The samples were <br /> collected using new, clean disposable plastic bailers Each sample was collected in two <br /> ' preserved 40-m1 VOA vials <br /> After collection,the samples were placed in a chilled container and transported under chain- <br /> of-custody to McCampbell Analytical, Inc (? TAI) in Pacheco, California for analysis Each <br /> sample was analyzed for TPH as gasoline and BTE&X in accordance with EPA methods <br /> 5030 and 602, respectively <br /> Samples were not collected from MW-1 and MW-4 because of the presence of free product <br /> However, the free product was hand-bailed from each well using a disposable bailer The <br /> ' removed product was placed in a DOT drum all drums N�ere stored across Monte Diablo <br /> Avenue at another property o"ned by AIr Russell Chapin <br /> ' 3.5.2 Groundwater Depth and Flow Direction <br /> Groundwater depth at the site on January 12, 1995 "as bew een 20 and 21 feet belo\% <br /> surface grade (bsg) Fiee product was encountered in MW-1 and MW-4 ho"e,.er, the <br /> adjusted groundwater depths are included in Table 2 <br /> Frguie 3 illustrates the elevation of the prezometrrc surface on January 12 1995 <br /> Groundwater flow direction at the site continues to be southwest, consistent %\rth previous <br /> measurements at the site <br /> 3.5 3 Laboratory Results of GroundNiater Samples <br /> Analytical results of all water samples are summarized in Table 3 No hydrocarbons N\ere <br /> detected in MW-2 However, TPH as gasoline was detected in samples from NII-3, ASO-1, <br /> ASO-2 and ASO-3 at concentrations of 2,200 ppb, 2,200 ppb, 58,000 ppb and 110,000 ppb, <br /> respectively, concentrations of BTE&X Nvere also detected in each of these wells The <br /> laboratory report and cliarn-of-custody is included in Appendix D <br /> 3.6 Vapor Extraction/In-Situ Air Sparging Pilot Test <br /> ' 3.6.1 The SAVE System <br /> On January 14, 1995, a 24-hour soil vapor extraction (SVE) and in-situ air spargrng (IAS) <br /> pilot test was initiated The pilot test was performed to piovrde additional vapor extraction <br /> ' penbyal quda Se— Io <br /> C1W'lh rRP/3 95,SC W 12 1ftS6.02 U <br /> 1 <br />