SITE INFORMATION AND CORRESPONDENCE 1995-2004

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James L. Tjosvold, P.E. November 5, 1996 Page 2 the Phase IV groundwater investigation. PG&E also presented the proposed remedial objectives and goals for soil and groundwater and the proposed points of compliance to be used in the FS during this conference call. Agency comments on the Phase IV Groundwater Investigation Draft Report, received by PG&E on July 9, 1996, were addressed by PG&E in a letter addendum dated August 7, 1996. On September 6, 1996, DTSC and the RWQCB commented on PG&E's August 7, 1996 letter addendum. On September 24, 1996, PG&E responded to the September 6, 1996 agency comments. "The Quarterly Monitoring Report, PG&E Stockton Former MGP Site, Second Quarter, 1996", containing the results of groundwater monitoring conducted in June, 1996, was submitted to DTSC and the RWQCB on July 31, 1996. The next quarterly groundwater monitoring occurred in September, 1996. The results of this monitoring were submitted to DTSC and the RWQCB on October 31, 1996 in the"Quarterly Monitoring Report, PG&E Stockton Former MGP Site, Third Quarter, 1996". II. Activities Performed During Current Ouarter: As agreed to at the May 22, 1996 meeting, PG&E is combining the soil and groundwater into a single FS. The draft schedule submitted to the agencies on June 6, 1996 included several agency meetings to be conducted prior to submittal of the draft soil and groundwater FS. These meetings and/or conference calls include discussion and agreement on: Area I soil source areas; ARARs; screening of soil and groundwater remediation technologies; VLEACH model and mixing cell model input parameters and preliminary model results; the use of the VLEACH model and mixing cell model during the FS; and preliminary and detailed evaluation of remedial action alternatives. Several of these meetings were conducted during the third quarter, 1996, as described below: • On August 8, 1996, PG&E, DTSC and the RWQCB met to discuss future activities at the site. Agreement was reached on the soil and groundwater goals for the FS (as discussed in PG&E's June 5, 1996 letter). It was also agreed that Zone A groundwater had been characterized, that no new Zone C groundwater monitoring wells are needed, and that PG&E will further characterize the soil source areas in Area I and investigate the diesel and PNAs found in Zone B groundwater in Area II. • On August 28, 1996, PG&E, DTSC and the RWQCB met to discuss input parameters to the VLEACH model; the groundwater mixing cell; preliminary VLEACH model results; and the application of VLEACH during the FS. In addition, agreement was reached on the soil data needs for defining Area I source areas.