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n 31 p Mr Martin Harris April 27,2004 r� Page 6 of 7 l other oxygenated gasoline additives were detected in the sample, although the field technician noted a"diesel"odor in water purged from the well Analytical results of soil and groundwater samples collected in January 2004 are summarized in Table 2 Laboratory reports and chain of custody documentation are included in Attachment D Confirmation groundwater samples collected from site wells in March 2004 contained substantially lower concentrations of gasoline constituents TPHg was detected only in wells MW1 and MW7 at concentrations of 720 ppb and 190 ppb,respectively Ethylbenzene and xylenes were detected only in well MW and 38 ppb and 37 ppb, respectively MTBE was detected in wells MW I, MW3, and MW5 at concentrations of 5 0 ppb, 12 ppb, and 3 1 ppb, respectively Analytical results of groundwater samples collected from site monitoring wells are summarized in Table 3 Field purge logs and the laboratory report for samples collected in March 2004 are included in Attachment E 4.0 SUMMARY Boring CPT1 and soil boring SB4 were advanced to approximately 35 feet bgs, and groundwater monitoring wells MW5 through MW7 were installed to depths of approximately 19 feet bgs to further investigate the nature and extent groundwater contamination beneath the site ® Soil beneath the site generally consists of sandy soil from the ground surface to approximately I 1-12 feet bgs, silt and clay from 11-12 feet to 16 feet bgs, sandy soil from 16 feet to 17 5-19 feet bgs, fine-grained soil from 17 5-19 feet to approximately 21 feet bgs, sandy soil from 21 feet to 26 feet bgs, fine-grained soil from 26 feet to 28 5 feet bgs, and sandy soil from 28 5 feet to 35 feet bgs, the maximum depth explored Field observations (odors, staining, PID readings) indicated that soil in the boring closest to the former UST (MW7) has been mildly impacted by petroleum hydrocarbons No constituents of concern were detected in the soil samples collected from borings MW5 and MW6 at the capillary fnnge Groundwater was first found at depths of approximately 8 feet bgs to 10 feet bgs during drilling Shallow groundwater near the former UST has been mildly to moderately impacted by petroleum hydrocarbon constituents Low levels of MTBE have migrated a relatively short distance downgradient of the former source In the most recent sampling event, none of the site wells contained MTBE at levels . exceeding the primary maximum contaminant level (MCL) of 13 ppb The secondary MCL of 5 ppb was exceeded in only one well (MW3 at 12 ppb) Groundze/souzalreports/WELLRPT2b doc