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i to position the sampler at the bottom of the boring. Therefore, 2-foot long, discrete-interval core samples were collected every 5 feet for the remainder of boring B3-3, using the Large- Bore Soil Sampler The Large-Bore Sampler is able to collect better samples under these conditions because the piston-tip of the sampler remains sealed (closed) as it is being driven. ' Groundwater was noted to be flowing into the boring at about 12 feet bgs and a groundwater sample was collected at this depth using the method described above at Site 2. Soil cores were visually examined for the presence of staining, discoloration, or odors indicative of petroleum hydrocarbon contanunation and these observations were recorded on ' the hthologic log (Appendix A). Weak to moderate product odor was first detected in core samples from boring B3-3 at about 10 feet bgs. Strong product odor together with greenish- gray to dark gray soil discoloration was detected within the interval from about 15 to 20 feet ' bgs. Selected soil samples were transferred to a clean plastic bag that was sealed for subsequent headspace screening using the PID The PID was also used to monitor ambient air , in the breathing zone around the boring and was used to periodically screen for volatile organics inside the open borehole. The PID values were recorded on the lithologic log (Appendix A) Discoloration in soils continued to about 25 feet bgs, while product odor ' diminished substantially below this depth The PID readings recorded from headspace screening of soil samples declined to non-detect below 30 feet bgs. After reviewing the core samples and PID recordings, Carol Oz of PHS/EHD requested that soil samples at 10, 16, 20, ' 35, and 40 feet bgs be submitted to the laboratory for PHC analysis from each of the three borings p1wed at the site. The second boring (B3-2) was drilled to a total depth of 41.0 feet bgs and was located approximately 23 feet north of boring B3-3, along the northwestern edge of the former UST ' --excavation-(Figure 3)=Two-foot�long-soil-core-samples=were collected every-Meet beginning - _ —at- feet bgs-using the Large-Bore�Soil Sampler. Soil samples were prepared for laboratory submittal as in boring B3-3. Discolored soils with strong petroleum product odor were detected beginning with the core sample collected from 14 to-16 feet bgs As-in boring-B3-3, -- soil discoloration and moderate to strong product odor continued to about 25 feet bgs, with ' product odor and PID readings diminishing substantially below this depth (Appendix A). A groundwater sample was collected at a depth of 13 feet bgs using the slotted-screen method described above. In addition, a depth-discrete groundwater sample was collected at a depth ' of 31 to 35 feet bgs to determine if groundwater was impacted with PHCs below the interval of strong soil discoloration and odor This groundwater sample was collected using a Geoprobe* Screen-Point Sampler which utilizes a 4-foot long, stainless steel screen that remains sealed while being driven to the target depth Following the collection of the soil core sample from 29 to 31 feet bgs, the sampler was attached to the probe rod and driven to 35 feet ' bgs. The sleeve shielding the screen was then retracted exposing the screen to the formation 6 98117ANVRPTS%S23U.9MN Rrr 1 1