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R603 UPDATE-32 9/8/94 .' INTRODUCTION This update, STATUS UPDATE 32 , presents data from August 8 , through September 2, 1994 . Site visits were conducted on August 17, 31 and September 2 , 1994 The permit to dump treated ground water to the sewer has been renewed. Presently we are batch dumping the treated water from the "ConVault" whenever it is full The water for treatment is collected from the vapor recovery condensate dropouts and produced from the sampling and monitoring of the monitor wells by Lawrence Tank Testing (LTT) pumping service The last batch dump occurred on December 22 , 1993 of 800 gallons LOCATION The station is located at 6425 Pacific Avenue at the intersection of Douglas Road, Stockton, in San Joaquin County, California. The site lies in Section 21 , T2N, R6E, MDB&M at approximately 12 feet above mean sea level (MSL) (see Figures 1, 2 , 3) The parcel is # 31 and can be located in Assessor' s Book 97 on page 41 (97-041-31) On October 2 , 1992, a licensed surveyor with Nolte & Assoc . surveyed all monitoring well locations and top of casing elevations to a known datum, i.e City of Stockton Bench Mark Number 12 , elevation 11 74 ' above mean sea level VAPOR RECOVERY OPERATIONS AND RESULTS The original REMOX unit operated for a total of 14452 hours out of a total of 21048 hours (690) As of September 2 , 1994 the new replacement unit operated 11304 hours out of 16797 5 hours (671) , for a total of 25, 756 out of 37845 5 hours (68%) As of September 2 , 1994 an estimated 73897 pounds of gasoline range hydrocarbons have been destroyed, see Table 2 and Appendix A - Air Monitoring Report Since February 18 , 1993 the vapor recovery/destruction has been declining from an average above 200 pounds per day of gasoline range hydrocarbons to a present low of less than 10 pounds per day of gasoline range hydrocarbons on April 26 , 1994 Presently the system is destroying a range from 6 to 1 pounds per day of gasoline range hydrocarbons SUMMARY There has been no 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 . The last evidence of product, as a sheen in the condensate recovery system, was on March 1, 1993 Vapor recovery has reduced the hydrocarbons in ground water significantly since the May 25, 1990 sampling, see Table 1 Using benzene as an indicator, monitoring wells MW1, MW4 , MW5, MW6 , MW7 and MW9 have been reduced to below detection limits while the wells being utilized for vapor extraction (MW2 , MW3 , PAGE 1