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AGI's mobile laboratory was present to-perform on-site chemical analysis for BTEX and TPHd on splits of the confirmation samples. The ability to generate accurate analytical results on location provided assurance that excavation objectives had been met and allowed immediate refilling of the excavation. The mobile laboratory reports are provided in Appendix B. 6.0 BIOREMEDIATION i During the course of the excavation, impacted soil wa"s- transported by Crisp Construction personnel in 'a dump truck to the treatment cell. Approximately 800 yards was moved between July 9th through July 13th. The treatment cell is located in. the east corner 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. The treatment cell was positioned at the east side of the site. The cell was 110 feet by 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 sal is achieved 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. Initial composite soil samples were collected from the approximately 800 cubic yards of soil staged at the treatment cell in a grid which is displayed on Exhibit 4. The TPH(diesel) concentration of the samples analyzed for July 13th range from 2900 to 270 ppm, respectively. The analytical results are included in Appendix C. Impacted 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. On October 6, 1993, Dave Derickson sampled the treatment cell in areas 2 and 7 in order to assess progress (Exhibit 5). At this time cell grid 2 contained 190 ppm TPH diesel and non-detect BTEX while-cell grid 7 was 32 ppm and non-detect BTEX. Due to TPH diesel in cell grid 2 being above the_ 100 ppm cut off, the treatment cell was allowed to remediate for another month. Then on November 9, 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 placed in an ice chest with temperatures at or below 4 degrees centigrade. These samples were then sent to 7 of 9 4