SITE INFORMATION AND CORRESPONDENCE 1993-1995

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James L. Tjosvold, P.E. September 15, 1995 Page 2 monitoring wells) would be postponed until PG&E had collected at least six sets of monthly groundwater elevation measurements. These water level measurements would be used to further refine gradient data, to enable selection of the optimal locations for the additional wells. After six months, the need to continue groundwater level measurements would be evaluated. On May 1, 1995, a revised schedule incorporating six months of groundwater elevation measurements prior to the Phase IV Work Plan submittal was sent to you. PG&E has collected six months of water level data for the three groundwater zones, A, B and C. However, we lack any water level measurements for Zone C during the Fall/Winter months and only have Fall/Winter water level measurements during November, 1992 and December, 1994 for Zones A and B. Because of this, PG&E proposes to collect additional water level measurements in all zones for the next four months (FaMinter) to determine if there is a seasonal change in groundwater direction prior to locating and installing the new wells. Therefore, PG&E has revised the schedule to incorporate time for collecting Fall/Winter water level measurements prior to submittal of the Phase IV Work Plan. The attached schedule incorporates four additional months of groundwater level measurements (through December, 1995) and submittal of the Phase IV Work Plan by January 8, 1995. During this time, PG&E will work with the City of Stockton to obtain permits to install monitoring wells along Hazelton Avenue. II. Soil Operable Unit Feasibility Study Submittal On August 17, 1995, PG&E submitted its proposed remedial actions objectives and goals for the Stockton project. These proposed objectives and goals were to be used to develop and evaluate possible alternatives in the soil operable unit feasibility study (soil FS) for the Site. In the August 17, 1995 letter, PG&E proposed submitting the draft soil FS to DTSC and the RWQCB within eight weeks of obtaining agency concurrence with the remedial action objectives and goals. During subsequent telephone conversations, Fernando Amador(DTSC) and Patricia Sullivan (PG&E) agreed that the soil FS would incorporate the following range of remedial goals: 1) cleanup soil to background levels; 2) remediate soil to reduce or eliminate future possible impacts to groundwater; and 3) maintain site cap and deed restrictions at site (no action). It was agreed that the soil FS would be submitted to DTSC by November 8, 1995. The attached schedule incorporates this understanding.