SITE INFORMATION AND CORRESPONDENCE 1995-2004

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Ms. Frances E. Anderson Page 5 and resolution of that issue, we are again simply directed in the DTSC cover letter of j December 26, 1995 that the "...RWQCB comments must be addressed". c The issue surrounding the completeness of soil characterization in Area I, as discussed in detail above, is another example where agency coordination in honoring prior approvals is lacking. The final point which bears discussion is the issue of uncertainty regarding the site. As the Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA makes clear(in Section 1.1), "...the objective of the RI/FS process is not the unobtainable goal of removing all uncertainty, but rather to gather information sufficient to support an informed risk management decision regarding which remedy appears to be most appropriate for a igiven si e e recognize t at t e reduction o uncertainty to levels which support an informed risk management decision is necessarily an iterative and interactive process. In this case, it is a process which has taken more than eight years and has cost PG&E in excess of$2 million. / Frankly, it is unfair to characterize our meetings and conference calls concerning the repeated investigations, draft soil operable unit feasibility study, treatability studies, and groundwater modeling which PG&E and its consultants have performed in good faith over the last two years as "not resulting in significant progress." The investigation and analyses which were the subject of those meetings were certainly undertaken by PG&E with the intention of satisfying the agencies' requirements. However, in many cases, the results of those efforts have been criticized by the agencies as not responding to uncertainties which, in PG&E's opinion, go beyond the standard of reasonability. For instance, your direction at our November 30, 1995 meeting was to use the Designated Level Methodology or its equivalent to demonstrate the potential effects on groundwater from chemicals in soils outside of PG&E's source areas. PG&E chose not to use the Designated Level Methodology in favor of what is, in our opinion, a more rigorous, / conservative model in general use, VLEACH. VLEACH is widely accepted by regulators at the state and federal level, and uses site-specific geologic information and chemical properties in the analysis. At our meeting to discuss the model results,the agency representatives focused principally on whether the model assumptions were sufficiently conservative, whether the data regarding Area I soils was sufficient for model input, and whether our sensitivity analysis was within sufficiently large bounds. While these are all legitimate elements for review and discussion(and, in our opinion, were fully satisfied in our presentation),their discussion was to the complete exclusion of the model results. As I discussed with you at that meeting, more communication and agreement among our respective staffs regarding model input before performing the model trials would have certainly streamlined the process--to a point. Considering the tenor of the agency comments at the meeting, however, it is unlikely that any level of discussion alone could have breached the data gaps perceived to be impeding acceptance of the model results.