ARCHIVED REPORTS_SITE CHARACTERIZATION WORK PLAN

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up to forty-five (45)soil borings on the property utilizing a combination of hand-auger and direct-push drilling techniques (Figure 3). Thirty (30) direct-push borings will be located in and around the northern and western portions of the former Time Oil terminal tank farm where documented unleaded gasoline spills occurred in 1981 and 1983, and the locations of the former ASTs and product piping. Fifteen (15) additional direct-push borings will be advanced in the area of the overhead truck loading rack and pump manifold. In each of the borings, soil samples will be collected at 2.5 and 5 feet bgs, and 0.5 to 1 feet above the soil/water interface (7.5 to 10 feet bgs) from each boring, and submitted for laboratory analyses. A log of each hand auger/direct-push boring will be prepared in the field. Soil samples will also be collected at 0.5 to 1 foot bgs from the twenty-five (25) borings located in the tank farm area to assess lead in soils related to historical surface coating maintenance of the former ASTs. Soil cuttings generated during direct-push boring activities will be placed in Department of Transportation (DOT) approved 55-gallon IA2 drums or an on-site roll-off box pending receipt of analytical results and subsequent disposal. Details and procedures for field screening and soil sample collection from the hand auger/direct-push soil borings and the associated laboratory analyses are presented in the Sampling and Analysis Plan (SAP) provided as Appendix B. 4.3 Hollow-Stem Auger Soil Borings/Monitoring Well Installation A California P.G. or a geologist working under the direct supervision of a California P.G will direct a California licensed well installer to advance up to sixteen (16) hollow-stem auger soil borings for the installation of additional B, C, and D Zone groundwater monitoring wells to better define the magnitude and extent of contamination in the intermediate and deep water-bearing zones. The wells will be installed near existing well TO/R-2R (B, C, and D Zone wells), west of Buckeye well AR/MW-5A (B and C Zone wells), west of Buckeye well AR/MW-8A (B and C Zone wells), near existing well TO/R-5R (B, C, and D Zone wells), near existing well TO/R-3R (B and C Zone wells), near existing well TO/WC-213 (C Zone well), and south and east of existing well TONT-2R(B, C, and D Zone wells). In order to better define the stratigraphy beneath the site, lithologic samples will be collected continuously from the C Zone wells west of AR/MW-8B and AR/MW-5A, the C Zone well near existing wells TO/R-3R and TO/WC-213, the D Zone wells near TOB-2R and TO/R-5R, and the D Zone well east of TO/T-2R. The anticipated total depths of the borings for the B, C, and D Zone borings are approximately 40, 75, and 85 feet bgs, respectively. Soil samples for laboratory analysis will be collected at 2.5 and Site Characterization Work Plan,Final, May 18,2012 1007-012,002 4-2