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a� KLEINFELDER equipment utilized to remove soil beneath the Chevron Pipeline after it is removed. Plate 7 is a cross section depicting the proposed excavation area beneath the Chevron Pipeline and the adjacent PG&E pipeline No. 2. An additional constraint was removal of soil in proximity to PG&E's Line 2 and related geotechnical considerations. Figure 7 was forwarded to both PG&E and Chevron Pipeline company for a response. It is Kleinfelder's understanding that the approximate excavator dimensions and weight shown, and trench excavation area in Plate 7 is acceptable to both companies for removal of soil beneath the Chevron Pipeline and adjacent to PG&E's Line 2. The proposed excavation is approximately 6 '/= feet deep and 6 feet wide, along approximately 300 linear feet of pipeline traversing the spill footprint area. Kleinfelder will provide confirmation soil sampling at the bottom of the excavation with direction from Chevron. I Kleinfelder anticipates collection of a bottom sample approximately every 50 linear feet. Both companies will have standby personnel present during removal of soil at the Chevron Pipeline. Based on preliminary indications from the bellhole excavation around PG&E's Line 2, excavation immediately around Line 2 is not anticipated, although removal of soil above Line 2 at depths from surface to about 3 feet bgs is expected with potential deeper soil removal in the vicinity of the rupture point. PG&E has requested confirmation sampling along additional areas of Line 2 trending through the oil footprint area. Kleinfelder has proposed sampling every 50 linear feet along Line 2, which would include about 5 additional sample points northwest of the initial bellhole excavation (Plate 6). Mr. Bryan Nicholson of PG&E has tentatively agreed and stated that either himself or another PG&E representative will be present to observe excavation of the Chevron Pipeline adjacent to Line 2 to observe soil conditions and potentially direct soil sampling in and around Line 2. Preliminary indications are that petroleum impacted soil was noted from surface to depths of about 3 feet bgs (2 feet above Line 2). Depth of contamination in the rupture area by Line 2, however, is likely deeper than 3 feet bgs. Field observations and soil sampling from the bellhole excavation around Line 401 indicated petroleum impacted soil right above and along the edges of Line 401, and therefore, for worker safety and potential corrosion issues, PG&E is requesting removal of soil on the top of Line 401, and likely from the sides as well. The bottom area may not need to be excavated, according to PG&E, if similar concentrations are detected beneath the pipeline as found during the bellhole excavation. Please note however, that PG&E has indicated that 2 feet of soil removal beneath Line 401 is sufficient even it higher contaminant levels are found. It has been agreed between Tom Crawford, PG&E Project Supervisor and Kleinfelder, that deeper excavation than two feet directly beneath PG&E's pipeline/s are not practical. t 44843.T04/STO5R1333/DH:Iv Page 6 of 17 ©2005 Kleinfelder, Inc. October 25,2005