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TPH-G was detected in groundwater samples collected from each of the three monitoring wells ' MW-1, MW-2 and MW-3 and from three of four push probe groundwater samples (GP-3, GP-4 and GP-5) Benzene was detected in each of the three monitoring wells and one push probe ' sample (GP-4) See Table 1 for a summary of the results The remaining BTEX constituents, toluene, ethylbenzene and total xylenes were not detected at or above laboratory reporting limits in groundwater samples collected from either the onsite monitoring wells or push probes GP-2 ' through GP-5 No water was available to collect from push probe location GP-1 Detectable TPH-G concentrations ranged from 22 to 2,000 parts per billion Benzene was detected in each of the monitoring wells and one push probe groundwater sample (GP-4) and ranged from 1 to ' 1,100 parts per billion For an approximation of benzene and TPH-G concentration isocontours see Plates 4 and 5, respectively Based upon the groundwater sampling results it appears the contaminant plume remains within the subject site but in close proximity to the northern border ' of the site The five oxygenates ETBE, MTBE, DIPE TAME and TBA and ethanol and methanol were ' found to be "none detected" in the four groundwater samples collected from push probe groundwater samples GP-2 through GP-5 ' Based on comparison to previous groundwater sampling results from monitoring wells MW-1, MW-2 and MW-3 it appears TPH-G and benzene concentrations Have generally decreased (Table 1) However, benzene concentrations found in groundwater samples collected at the site during the June 2000 push probe assessment and the July 2000, first semi-annual groundwater sampling event have been found to exceed State and Federal MCLs of 1 µg/l and 5 µg/1, respectively ' 7.2.2 Soil Sampling Results A single soil samples from each of the push probes GP-1 through GP-5 (five soil samples) were submitted for analyses for petroleum constituents Each of the five soil samples submitted for ' analyses from the push probe locations were collected at the estimated capillary fringe area at depths ranging from 28 to 32 feet bgs Four of the push probe locations were advanced north by northwest of the former UST and one push probe was advanced south of the former UST at the request of Mr Mike Infurna from PHS/EHD Mr Infurna additionally stated that only the soil sample from the push probe with the highest PID reading would need to be analyzed for oxygenates, methanol and alcohol That locatior was GP-3 located north by northwest of the former UST Push probe GP-3 had a the highest PID reading of 9 ppmv None of the requested petroleum constituents were detected at or above laboratory reporting limits for these five soil ' samples Based on review of soil logs for the five push probe locations, three monitoring wells and other former boring locations (Plate 2) it appears that the soils within the water bearing zones (depths near 28 feet bgs and deeper) are predominantly clay with discontinuous layers of silts and some sands Clay was present in the water bearing zones in push probes GP-3, GP-4 and GP-5 and monitoring wells MW-1 and MW-3 Silts and clayey silts were found at depths of 33-43 feet bgs 20-4439-01 E01/2000R726 Page 12 of 17 ' Copyright 2000 Kle►nfelder Inc October 16,2000