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R604 :UPDATE 9-MARCH, 1992 • VAPOR RECOVERY RESULTS UNDER VARIANCES # 91-19 AND 91-20 . The vapor extraction system was shut down on November 21, 1991 upon completion of operation under Initial Variance #91-19 and 90 day Variance #91-20 . A total of 13 , 116 pounds of gasoline range hydrocarbons was removed from the soils and ground water beneath this site by that time. The vadose zone vapor recovery wells (P1 , P3-Swarm and EX) contributed little to the total recovered hydrocarbons during this time period, P1 = 1 . 3 pounds, P3-Swarm = 561 . 4 pounds and EX = 127 pounds, see Table 3A "RE-EQUILIBRATION" OF HYDROCARBON PHASE IN VADOSE WELLS (P1 , P3- SWARM AND EX) . P1 P1 was placed back on line on November 6, 1991 , after being off line since September 25 , 1991 . November 12 , 1991 analysis of P1 displayed a relatively flat line chromatogram, the minute peaks found on the chromatogram are most likely attributed to residual compounds from the earlier analysis of the calibrant, P1 was then taken off line and used to show vacuum influence from the other • vadose zone wells, P3-swarm and EX. The vapor recovery system was turned off on November 21, 1991 but restarted briefly on December 16 , 1991 , to test the vadose wells after a period of "re- equilibration" had occurred. P1 was hooked into the vacuum system at this time and a sample obtained from the orifice for that well was analyzed using the 10 s 50 PID chromatograph. After completion of sampling the wells, the vapor recovery system was shut off. The resulting chromatogram showed only instrument noise. Another site visit occurred on January 27 , 1992 . P1 , P3- Swarm and EX were connected to the vacuum recovery system and the system restarted. A sample of the effluent from the pumps was then obtained and then the vacuum recovery system was dismantled. The resulting chromatogram was a flat line, indicating the absence of gasoline petroleum hydrocarbons in the areas of the vadose wells. The P1 well has never showed much vapor recovery and the area around the well is know void of petroleum hydrocarbon vapors indicating the Lack of petroleum hydrocarbons in the soil . P3-Swarm P3-Swarm wells P3. P3A and P3D have been continuously pulled from since their installation. The chromatogram produced from the analysis on November 21 , 1991, shows a relatively flat line, with minor response probably being attributed to residual peaks from the previous analysis . The vapor recovery system was then shut off and two periods of "re-equilibration" occurred. The first . period ended on December 16 , 1991 , when the vapor recovery system was briefly re-started during the site visit to sample the ground water monitoring wells. The resulting chromatogram was a flat page 7