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Mr Jeffrey Wong Page 6 of 7 • readings in soil samples from the well suggested contamination was present from a depth of approximately 15 feet to at least 70 feet Laboratory analyses of soil samples, however, detected gasoline hydrocarbons in soil only from 20 to 30 feet The presence of apparent hydrocarbon odors, unverified by laboratory results, is similar to the situation at the subject property Relatively high concentrations of gasoline hydrocarbons were initially present in groundwater samples from well MW7 More recently, however, concentrations have been minimal A review of water level data indicates that depth to groundwater has fluctuated between 36 and 63 feet below grade since 1995 and the well screen has been submerged for some time Groundwater flow has ranged from northeasterly to southwesterly The water level data do not tend to support a mechanism for introducing contaminants to the 20-30 foot soil interval by groundwater transport We understand that new monitoring wells with higher screened intervals have been recently constructed at the site Data regarding groundwater flow and contaminant concentrations as determined from these wells has not yet been released 5.0 CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions • Groundwater, vadose soil and saturated soil in the vicinity of the former UST are significantly impacted by gasoline hydrocarbons No gasoline oxygenates were detected in the soil or groundwater • High concentrations of TPHg and BTEX in the groundwater suggest that free product may develop, however, none was observed during well development and groundwater sampling • Soil contamination of significance does not appear to be present below 80 feet bgs • The absence of soil contamination at some distance laterally from the release area has been confirmed Despite suspected hydrocarbon odors in soil in closer proximity to the release area these soils may be unaffected 5.2 Recommendations Based on the above conclusions Ground Zero recommends that additional borings and monitoring wells be advanced at the site in order to delineate the lateral extent of the contaminant plume, both in soil and in groundwater However, until additional data from the adjacent site to the northwest is reviewed for groundwater gradient and contaminant distribution no reasonable well locations can be proposed at this time &talgrounzelhairyslsumrpt doc