SITE INFORMATION AND CORRESPONDENCE

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log sro 27 March 2007 / ✓ / �j, AGE-NC Project No. 97-0249 " Page 6 of 7 • MTBE was not detected in HU3 this quarter; well MW-14C was inaccessible and was not sampled this quarter. • 1,2-DCA was detected ingroundwater samples MW-lthroughMW-6,MW-8A and MW-10 (A, B) at maximum concentrations of 41 µg/1 from well MW-3. The estimated extent of dissolved 1,2-DCA in HU 1 is depicted on Figure 11. 1,2-DCA increased from non detect the second consecutive quarter in samples from wells MW-6 and MW-10A; 1,2-DCA was detected for the first time since sampling began in the sample from well MW-5. 5.0. RECOMMENDATIONS Based upon the results of the fust quarter 2007 investigation, AGE presents the following recommendations: • Continue quarterly ground water monitoring at wells MW-1 through MW-17; the second quarter ground water monitoring event was performed in April 2007,and a report of findings is forthcoming. • The adjacent Flag City Chevron is currently being considered for closure by the CRW QCB; due to the location and screen intervals of Flag City Chevron wells MW-11, MW-12, MW-13,MW-16,MW-17 and MW-18 on or near the 3B's property,responsibility of these wells should be transferred to the 3B's investigation. • Due to marginal delineation of the soil plume,additional soil investigation may be warranted beneath the former UST area, in the current gasoline and diesel fuel dispenser areas, and west-northwest of MW-3, which should coincide with the installation of any future remediation wells (i.e. soil vapor extraction wells). • Generally,the core of the dissolved petroleum plume appears to located in HU 1 within the area of wells MW-1, MW-2, MW-3, MW-6, MW-8 and MW-10; outside of the dissolved petroleum core area,only low petroleum concentrations have been detected on-site towards the north (MW-5), and towards the southwest (Flag City Chevron MW-13). Based on the data collected during the first quarter 2007,additional ground water monitoring wells are not warranted at this time and the existing monitoring well network may be sufficient to complete a site Corrective Action Plan (CAP). Advanced GeoEnvironmenfal,Inc.