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CLOSURE REQUEST 5-31-94 deep in 97 cubic yard increments . Sampling of this aerated soil on August 16, 1990, indicated that the only component remaining was kerosine range hydrocarbons that ranged from 30 to 140 mg/Kg; BTEX were below detection limits . This soil was used at the top of the backfill of the UST excavation. Over-excavation of the pump island areas generated approximately 350 cubic yards of soil . Laboratory results of the samples obtained August 22, 1990 indicated that the majority of the soil was below 50 ppm TPH in the kerosine range with minor toluene, ethylbenzene and xylenes . Aeration of this soil commenced on September 6, 1990 . Sample results obtained on September 19, 1990 showed the soil to be below detection limits for petroleum hydrocarbons and BTEX Approximately 30-40 cubic yards of soil was generated from deepening the eastern and western pump island excavations to the 20 foot depth. A composite sample of this excavated soil showed Y only 18 ppm as kerosine range hydrocarbons was in the soil, this soil was spread thinly on the asphalt and left, see Table 5. Aeration of the soil was performed in the following manner. 1 . Using a front end loader with a one yard bucket approximately the permitted amount of the stockpiled soil was removed from the covered piles and then the piles were recovered 2 . The removed soil was then aerated by moving the soil with the bucket of the loader to various locations within the aeration zone and forming numerous small piles These piles were continually reworked throughout the day 3 Towards the end of the day, the individual small piles were combined and then spread upon the aeration area at approximately a 6" thickness and left to aerate. 4 . Once field screening with a HNu PID indicated the soil to be clean it was repiled and covered and a fresh segment of soil was removed from the stockpiled covered soil piles and aerated in the same manner. This was performed until all of the excavated soil had been worked in this manner 5 . Once the certified laboratory results showed that a soil segment was below detection limits for gasoline range hydrocarbons, benzene, toluene, ethylbenzene and xylenes and below 100 ppm TPH for kerosene or diesel range, that soil was placed into a completed aeration pile and later used for backfill on site IN-SITU VAPOR EXTRACTION Laboratory results of the samples obtained from the over- excavations and soil borings performed on site indicated that further excavating would not be cost effective to remove residual soil contaminant . Ground water also needed to be remediated. Due page23