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24 March 1993 (GeoAudit 640-S) Page 4 of 5 respectively) . Benzene, toluene and ethylbenzene were not detected in any of the soil samples. Xylenes were detected only in sample B3-20 (at a depth of 20 foot depth) at a level of 0. 22 µg/g (ppm) . TPH as gasoline was detected in sample B3-20 at a leve pm. No TPH as gas was detected in any other soil sample. The analytical results are summarized in Table 3 . The laboratory report and chain of custody are attached in Appendix A. Benzene and ethylbenzene were not detected in any of the water samples. Toluene and xylenes were detected only in the sample from MW-2, at levels of 0. 38 µg/L and 2 .2 µg/L (ppb) , re egt-iv 1 . TPH as gasoline was detected in the sample from MW-2 a 530 f�ppb) . TPH as diesel was detected in the sample from MW-5 at 80 ppb (no other sample was analyzed for TPH as diesel) . TPH as gasoline was also detected in samples from MW-4 and MW-5 (110 ppb and 290 ppb, respectively) . However, according to Alpha Analytical Laboratories, 50% of the gasoline contamination in MW-4 and 97% of the gasoline contamination in MW-5 is "an isolated peak between benzene and toluene" (see laboratory report) . To identify this peak, the sample from MW-5 was analyzed for halogenated / volatile organics. Of the 31 HVO analytes, only 1, 2-Dichloropropane ✓_ was detected (330 ppb) . The water sample analysis are summarized in Table 4 . The laboratory report and chain of custody are attached in Appendix B. CONCLUSIONS The analytical results of the soil samples indicate that the soil contamination associated with the former underground storage tank is limited in lateral extent above groundwater levels. Only one soil sample contained any hydrocarbon contamination (B3-20; MW-2) and this sample is well within the saturated groundwater zone (20 feet in depth) . The limited contamination in this boring indicates that hydrocarbons in the vadose zone are present primarily beneath the former location of the UST's. Because of the limited lateral extent, the soil contamination can probably be remediated by excavation and either on-site treatment or off-site disposal. TPH as gasoline in the water samples (except MW-5) are contoured in Figure 4 . The TPH value of the sample from MW-4 was adjusted to represent only the gasoline fraction in the contour map. The dissolved hydrocarbon plume apparently extends off-site from pastern side of the property. Additional investigation on the neighboring property to the east will be probably be required in y order to fully define the contaminant plume.