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+1 T Mr Micheal Infurna • 4 sand was observed in the upper portion of the sample collected from 34 5 to 36 feet bgs The lower portion of that sample interval contained silt as did the sample collected from 39 5-41 feet FID readings ranged from 800 parts per million (ppm) in the 25 foot sample to > 10,000 ppm in the 15, 20, and 35 foot samples, Discoloration of the soil was present as a gray mottling in the samples collected from the 24 5-26 and 34 5-36 foot intervals Petroleum hydrocarbon odors were noticeable throughout In borings MW 1 and MW3, groundwater was first encountered in sands at a depth of approximately 23 feet bgs In boring MW2, groundwater was not observed until a depth of approximately 30 feet The water level in this boring subsequently rose to approximately 23 feet bgs The evidence indicates that the shallow aquifer at the site is unconfined and not confined as previously reported However, the fine grained sequence in the immediate area of the former UST is very slow to yield and gives the appearance of local confinement Soil and Groundwater Analytical Results The soil samples collected from borings MW 1 and MW3 did not contain any detectable amounts of TPHg or BTEX The soil sample collected from MW2 at a depth of 20 feet, contained 1,200 parts per million (ppm) TPHg, <0 75 ppm benzene, 45 ppm ethylbenzene, 81 ppm toluene and 200 ppm total . xylenes The soil sample collected from MW2 at a depth of 40 feet contained 210 parts per mullion (ppm) TPHg, 2 2 ppm benzene, 18 ppm toluene, 7 3 ppm ethylbenzene, and 25 ppm total xylenes Soil analytical results are summarized in Table 1 Laboratory reports and chain of custody documentation are included in Attachment C The groundwater analytical results in wells MW 1 and MW3 were reported as non-detectable for TPHg and BTEX In well MW2, TPHg was detected at a level of 120,000 parts per billion (ppb) Benzene, toluene, ethylbenzene and total xylenes were detected at concentrations of 20,000 ppb, 38,000 ppb, 7,800 VV6 F )pb, respectively Gfoundwater analytical results are summarized in I able 2 Laboratory reports and chain of custo y documentation are included in Attachment C CONCLUSIONS Groundwater, vadose soil and shallow saturated soil in the vicinity of the former UST are impacted by gasoline hydrocarbons The relatively high concentrations of TPHg and BTEX reported in groundwater from well MW2 suggest that free product may develop, although none was observed during the current investigation Wells NMI and MW3, located upgradient of MW2, contained no detectable concentrations of petroleum hydrocarbon constituents The extent of downgEadient contaminant migration is currently unkaom4 The vertical extent of soil contamination appears to have been defined by the work previously completed by Philip Environmental Soil contamination of significance does not appear to be present beneath a depth of approximately 45-50 feet The lateral gregersulaubaud rpt