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r EVAX Project 8239-02 April 7, 1992 Joe Soil Sampling The borings were advanced to a depth of between 15 and 20 feet below ground surface and soils were sampled at 5 feet depth intervals. At i each sampling interval , soil samples were taken using a California modified, split spoon sampler loaded with 3 steam cleaned, brass sleeves each of 2-inch diameter and 6-inch length. Sampling involved advancing the boring to a point just above the sampling depth, sliding the sampler loaded with brass sleeves through the hollow stem of the augers, and then driving the sampler 18 inches into the relatively 1 undisturbed soils with a standard 140-pound hammer dropped repeatedly 30 inches. The number of blows needed to drive the sampler each successive 6 inches was recorded by the geologist. Heaving sands were encountered below groundwater level in the borings. Soils were examined and characterized by the EVAX geologist with 1 reference to the Unified Soil Classification System. Soils were field screened with a Heath Tech Porta Model flame-ionization detector (FID) . The portable FID is a gas analyzer that measures, on a qualitative basis, total volatile hydrocarbon/organic content. A portion of the soils retrieved from each sampling interval was placed in a zip-lock plastic bag. The bag was sealed and, after approximately 5 minutes, Ie the intake probe of the FID was placed in the head space of the bag and an FID reading was taken. The geologist also examined soil cuttings emerging from the augers during the drilling of the borings. Geological and other field data are summarized in the Logs of Borings/Wells, Appendix B. 1 The geologist selected 8 soil samples to be analyzed for gasoline product constituents. The samples represented soils taken at or near the current groundwater level , and soils considered from field observations to be impacted by hydrocarbon products. Sample BI-W represented soils with a slight product odor taken from the boring of MW-1 at approximately groundwater level , 8 to 9 feet below ground surface. Sample B1-10.5 represented soils from the MW-1 boring at a depth of approximately 10.5 feet below ground surface. Samples B2-6.0, B2-10.5, and B2-15.5 represented soils from the boring of MW-2: B2-6.0 was taken immediately above groundwater level at a depth of 6.0 feet, and B2-10.5 and B2-15.5 were taken below groundwater level at a depth of 10.5 and 15.5 feet, respectively. Samples B3-6.0, B3-10.5, and B3- 15.5 represented soils taken at corresponding depths from the boring of MW-3. A chain of custody record was initiated in the field and followed the samples to the laboratory. -3-