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r r R603 UPDATE-18 7/09/93 CONDENSATE REMOVAL AND WELL PURGING BY LTT Condensation from vapor extraction is collected in moisture drop out tanks constructed of 12" PVC pipe, before the manifold, to prevent moisture build up on the vacuum pump filter. All fluids removed from the condensation traps are placed in the 1000 gallon "ConVault" Table 4 represents the field notes from LTT condensate removal and well purging (MW2 and MW3 condensate into the same trap and the condensate removal is represented with MW2 data) , see Appendix B . As of May 24 , 1993 LTT has removed an estimated 4063 gallons of ground water from MW1, MW2 , MW3 , MW8, MW10 and water condensate from traps for MW2&3 , MW10, EX and 26 25 gallons of product from the condensate traps . Total fluids removed as of May 24 , 1993 . 4225 gallons of ground water/condensate water and 48 75 gallons of product (162 previously recovered condensate water and 22 5 gallons of product) 4 . 0 SUMMARY There has not been any evidence of floating product or product sheen on the ground water in MW1 since April 14, 1992 and MW3 and MW10 since November 11, 1992 Only occasional product sheen is found with the condensate recovered from the vapor extraction moisture dropouts and manifold Vapor recovery and well purging has reduced the hydrocarbons in ground water significantly since the May 25, 1990 sampling, see Table 1 . Using benzene as an indicator, monitoring wells MW4, MW5, MW6 , MW7 and MW9 have been reduced to below detection limits while the wells being utilized for vapor extraction (MW1, MW3 , and MW10) have been reduced by better than 99% MW2, which is also utilized for vapor extraction has been reduced 81% and MW8 has been reduced by approximately 2216 . Of the newly installed wells MW11 and MW12 , MW11 has always tested below detection limits . MW12 has not shown any significant change in benzene concentrations On June 14 , 1993 , a sample of the water being treated by air stripping inside the "ConVault" was obtained for certified laboratory analysis, before dumping approximately 800 gallons of this water to the City of Stockton' s sanitary sewer, see Appendix A As of June 22, 1993 , an estimated 20658 gallons of gasoline range hydrocarbons have been removed from the soil and ground water beneath this site . Previously removed floating product (40 25 gallons) , condensation from vapor extraction (48 75 gallons) , projected petroleum hydrocarbon in situ oxidation CO2 vapor recovery (59261 pounds/6 . 25 pounds/gallon = 9481 76 gallons) and vapor extraction-destruction of hydrocarbons (69298 pounds/6 . 25 = 11087 68 gallons) No chlorinated solvents were detected in chromatogram comparisons, "i . e " 1, 2 , -Dichloroethane (DCE) - retention time 2 . 079 minutes, Trichloroethylene (TCE) - retention time 3 023 minutes and Tetrachloroethylene (PCE) retention time 3 75 minutes . a PAGE 3