SITE INFORMATION AND CORRESPONDENCE

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Geweke, FRP - 2 - 20 September 1993 , basis. The borings will be sampled every five feet and monitored in the field with a PID. Selected soil samples will be analyzed for TPHg and BTEX. The results will be compared to baseline samples. GeoAudit states that this soil bioremediation procedure will not affect the ground water, and, therefore, no Regional Board permit will be required. To bioremediate the ground water, they propose to introduce the bacteria through existing unspecified monitoring wells. To monitor the effectiveness of the bioremediation, GeoAudit recommends monitoring off=site monitoring wells, MW8, MW9, MW11, MW12, and MW13 on a monthly basis during the first quarter after inoculation. This monitoring is to ensure that the contamination has not migrated ahead of the bacteria. The samples will be analyzed for TPHg, BTEX, and pH. Monitoring pH may ensure that carbon dioxide "is not adversely affecting ground water quality". Because of the "indigenous nature of the bacteriological culture, not composing a waste or waste product, it is not anticipated that a waste discharge permit" will be required. Geweke would like to prepare a negative declaration in lieu of a permit. GeoAudit states that the completion time for in-situ bioremediation is dependent upon the number of inoculation wells, the number of inoculation events, the rate of bacterial migration in soil, and the suitability of selected bacterial cultures to the contaminants. In sandy soil GeoAudit estimates that it could take 12 to 24 months and up to 36 months in clayey soils. They assert that active in-situ bio has the potential to remediate soil and ground water to non-detectable levels. Because of the significant quantities of soil contamination, the fluctuation of ground water, and permit acquisition, GeoAudit proposes to initiate soil remediation in the first phase, immediately upon approval of the regulatory agencies, and to begin ground water remediation in the second phase, at a later date. COMMENTS GeoAudit was told by me, in June 1993, and subsequently by Pat Leary, that Waste Discharge Requirements were necessary for the discharge of the bacteria and medium to ground water. Pat recently sent a letter to the dischargers, requiring submittal of a Report of Waste Discharge and fee. This discharge falls under the General Permit for Underground Tanks but issuance of the permit will likely cause Geweke to miss their deadlines. The C&A requires that they begin startup activities by 15 October and begin remediation by 15 November 1993. There were several discrepancies in the text, figures, and Appendix C. Some of the cross-sections refer to borings or wells, GL-3 and GL-4, that are not described in other figures or the text. Other wells, VW-1 through VW-4, are mentioned in the text but not shown in the figures. The letter in Appendix C is addressed to me, however, the letter is unsigned, has no signature block, and I have not received a copy of this letter by mail or Fax. No mention is made of identifying or remediating the soil in the "smear zone" or soil zone that has become contaminated due to contact with fluctuating contaminated ground water. The extent of soil contamination shown in the FRP is limited to the vadose zone above the water table and smear zone. A complete description of the vertical and lateral extent of soil contamination must include the