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baseline conditions. Hence, this data establishes pre-existing sulfur concentrations in the soils of the site and ground water. Similarly, sulfates were detected at 9,400 mg/kg (one order of magnitude above the highest sulfate value detected in the ground water sample from MW-2) in the site's soils, once again establishing pre-existing conditions on site. Water levels appear to have risen about three feet since 1991 on the basis of the available Dames and Moore data. If groundwater had been found to occur at shallower depths and in contact with the background sulfur or sulfate (737 mg/kg of sulfur and 9,400 mg/kg of sulfate), it may cause a rise in those concentrations compared to1991. Relatively low TOC in groundwater is interpreted as background for the aquifer sediments. The presence of Chrysene in MW-3 was the only detection of a PAH. Dames and Moore had detected Pyrene and Fluoranthene in soil at 0.5 feet from MW-4 and their Total Recoverable Petroleum Hydrocarbon (TRPH) data showed detection in all samples (range from 33 to 190 mg/kg). This shows a background of TRPH and possible PAH in the surface soils and sediments. Dames and Moore had attributed treated wood fragments in surficial fill soils as a possible source of PAH in their report. However, MSC's most recent storm water data from the 2002 season (see Appendix C) revealed non-detected concentrations of PAH in the storm samples. Moreover, Dames and Moore's data revealed Di-n- Butyl Phthalate at 1.1 mg/kg in sample MW-3B-10.0 (10 feet deep). In view of the above, in our opinion, the presence of Chrysene is attributed to low background concentrations within the sediment and fill of the area. VII. Conclusions and Recommendations TRE has sampled the four existing groundwater monitoring wells on industrial Parcels 1, 2, and 3 at the MSC site. These wells were repaired and redeveloped prior to sampling for selected inorganic and organic parameters. The wells had apparently not been sampled since 1991/1992, and only Dames and Moore data for Wells MW-1 and MW-4 were available for comparison of ground water samples. However, soil samples results were also available and used as indicators of pre-existing conditions for the site. Groundwater flow was plotted as south-southwesterly over the site. A localized groundwater mound occurs near Well MW-2 and is attributed to the nearby pond that caused a localized effect. Analyses for PAH in 1991 and storm water did not reveal any PAH. Since Dames and Moore only sampled MW-1 and MW-4, there are no comparisons for MW-3. The only PAH detected was Chrysene, which was detected at 17 ugh I in MW-3, and the other three wells showed non-detected concentrations of PAH. Dames and Moore did observe a widespread background of TRPH and detected 9