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R603 UPDATE-25 2/10/94 . Currently the ground water is in a continuation of a recharge cycle produced from the Spring of 1993 precipitation, see Depth to Water measurements on Table 1 . As would be expected, changes in vacuum at the wells influences the shape of the potentiometric surface. GROUND WATER QUARTERLY SAMPLING Ground water samples were collected on December 22, 1993 , see Table 1 . These samples were collected by a WEGE Geo-technician and "Chain of Custody" delivered on ice to a State certified testing laboratory (SUPERIOR PRECISION ANALYTICAL, INC. DHS #1332) for chemical analyses . These samples were analyzed for TPH and BTEX concentrations using EPA Methods 8015 and 602 respectively. Since diesel has never shown up in the sample results, the samples obtained on 11/27/90 and later were analyzed using EPA methods 5030 and 602 for Total Fuel Hydrocarbons and BTEX The next quarterly sampling will occur in March, 1993 . 3 . 0 RESULTS GROUND WATER SAMPLE RESULTS Ground water samples were obtained from all of the monitoring wells on December 22, 1993 . The latest sample results showed a continual decline in contaminant levels associated with the ground water at MW1, MW2 , MW4 , and MW8 The other wells that have some degree of ground water contamination (MW3 , MW10, and MW12) showed increases, see Table 1, Figure 5 and Appendix C The increase in contaminant concentrations found at MW3 , MW8 and MW12 is thought to be associated with the vacuum extraction system being turned off at times due to equipment modifications (heat exchanger addition) and equipment check (increase noise from compressor) , see Tables 1 and 3 . VAPOR RECOVERY OPERATIONS AND RESULTS On December 18, 1993 , the REMOX unit was off During this site visit a WEGE technician tried to restart the unit, but could not . A REMOX technician, after some repairs, restarted the unit noon February 2 , 1994 The REMOX units have operated for a total of 11515 hours out of a total of 18329 hours (6310 The new replacement operated 7767 hours out of 11712 hours (66%) . An estimated 72119 pounds of gasoline range hydrocarbons have been destroyed, see Tables 2, and 3 and Appendix D-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 low of 30 pounds per day of gasoline range hydrocarbons on July 19, 1993 . With the addition of the heat exchanger, and corresponding vacuum and air adjustments, the PAGE 2