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AGI''s mobile--laboratory was.present to .perform on-site chemical analysis for BTEX . ru and TPHd on splits of the confirmation samples. The ability to generate accurate __analytical results on location provided assurance.that excavation 'objectives had been n met and allowed immediate refilling of the excavation. The mobile laboratory reports -- are provided in Appendix B. x -= 6.0 BIOREMEDIATION During the course of the excavation, impacted soil was transported by Crisp Construction personnel°in a. dump truck to the treatment cell. Approximately 800 - Ea yards was moved between Jul 9th through Jul 13th. The treatment cell-is located in Y Y 9 Y the east comer of the property. Once impacted soil had been moved to the cell, Solmar Corp L-104 biocultures were introduced to the soil for remediation purposes. The biocultures were previously mixed with fertilizer and water to optimize bioactivity. = Ey The treatment-cell-was positioned at the east side of the site. 'The cell was 110 feet by i 95 feet and accommodates impacted soil to a depth of:2 feet (Exhibit 4). The bottom of the cell is lined with Visquene plastic sheets. Containment of impacted soil is achieved Alf : by 3 112 to 4 foot earthen berms which are also lined with plastic sheeting to separate . the clean soil of the berms from the impacted soil of the excavation. E Initial;composite soil samples were collected from the approximately 800 cubic yards s :of.soil staged at-the treatment cell in a grid which is displayed on Exhibit 4. The - 9TPH(diesel).concentration of the samples analyzed for July 13th range from 2900 to 270ppm, Erespectively. The analytical results are in in Appendix C. Impacted r soil-from the excavation remained on site until concentrations were remediated to approximately 100- ppm-level. The treatment cell was disked and kept moist by Leonard Crisp on a bi-weekly schedule in order to enhance remediation. ri October 6, 1993,..Dave:Derickson-sampled the treatment cell in areas 2 and 7 in tE- order to assess progress(Exhibit 5). At this time cell grid 2 contained 190 ppm TPH f4 diesel and non-detect BTEX while cell grid 7 was 32.ppmand non-detect BTEX. Due � to TPH diesel in..cell grid 2 being above the x 100 ppm cut off, the treatment cell was u z allowed to remediate for another month. Then on November9,_1993; Dave Derickson - . = :composite`sampled..cell grid 5 which resulted in 0.8 ppm TPH diesel and a non-detect for BTEX. At this:juncture AGI proceeded ahead for final sampling of the treatment cell. +° = Final sampling occurred on December-3, 1993 and was witnessed by Michael Collins, = San Joaquin PHS/EHD. Sampling was performed by retrieving representative samples from four spots.within each cell from a depth of approximately 1 foot below -grade. A single composite sample was generated for each cell. Samples were placed in brass sleeves which were sealed with teflon and then n placed in an ice chest with temperatures at or below 4 degrees centigrade. These samples were then sent to Ai 7of9 -^ qH