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.. Coca-Cola Enterprises - West -,, Job No. 90054 of contamination, to provide a stratigraphic description of the subsurface, and to obtain selected soil samples for chemical analysis. All borings were drilled to a minimum depth of 65 feet below grade using a truck-mounted drilling rig equipped with 7-inch outside diameter (O.D.) continuous-flight hollow-stem augers (Photograph No.2). Boring locations were selected in the field on the basis of the soil gas survey results, visual observations made during the tank removal operations, and overall vertical and lateral site coverage. Boring locations are shown on Figure 3. i Soil samples were collected at 5 or 10 foot intervals starting at depths of 5 or 10 feet and ' continuing to the full depth of exploration. All soil samples were collected in general accordance with American Society of Testing and Materials (ASTM) method D-1585. Samples were collected with a 3-inch O.D. modified California split-barrel sampler containing three 2 1/2-inch diameter by 6-inches long brass sample retainers. The sampler was lowered through the center of the auger and driven in front of the auger bit into the undisturbed soil with a 140- pound drop hammer. The sampler was then withdrawn (Photograph No. 3) and opened to obtain the samples. The penetration resistance values (i.e.blow counts) for each sample interval are recorded on the edited boring logs. The edited boring logs are presented in Appendix C. Upon retrieval, soil from the upper retainer was examined visually for organic contamination by the USTEC field geologist and then classified in general accordance with the Unified Soil Classification System (ASTM Standard D-2487). The middle sample retainer was prepared for submittal to Sequoia Analytical Laboratory,Redwood City,California,for chemical analysis. The lower sample was used for organic vapor monitoring and sample screening (Photograph No.4). The procedures followed for vapor monitoring are described in Section 3.6. 3.4 GROUNDWATER MONITORING WELL CONSTRUCTION j Borings 132, B3, B6, B11, and B12 were completed as groundwater monitoring wells MW-1 . through MW-5, respectively. Groundwater monitoring wells were installed through 8 5/8- } , itch inside diameter (l.D.) hollow-stem augers. The groundwater monitoring wells were n„ constructed of a single string of 4-inch O.D., schedule 40, flush-threaded polyvinyl chloride (PVC) well screen and blank casing. A 30-foot length of PVC well screen with a slot size of 1 ? O.OIO-inches was installed at depths ranging from 90 to 82 feet with about 10 to 15 feet of well 6 ; Old