SITE INFORMATION AND CORRESPONDENCE

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RJ • • 23 December 2002 AGE Project No. 96-0229 Page 2 of 3 southeast ofthe Top Filling Station and immediately south of the Knowles/Roek Property. Historically, SEI has reported elevated MTBE concentrations in their ground water monitoring wells MW-1,MW-4,MW-5,MW-6 and MW-8.MTBE was reported during their September 2002 monitoring event at concentrations as high as 69,000 µg/l. 4. AGE is in the process of installing off-site multi-level wells to help delineate and/or differentiate the impacted ground water plumes from the three above referenced sites. AGE has obtained an off-site access agreement with Goodwill Industries to install one .multi-level well ncrldicast of the Tc—Filling Stat,'-_n a*. 66 South Wilson Way. AGE is currently working with GZA in preparing an off-site access agreement that will allow AGE to install two additional multi-level ground water monitoring wells on the Knowles/Roek Property. 5. AGE discussed the need for interim remediation(i.e. ground water extraction) at the site to implement hydraulic control and inhibit further offsite migration of the dissolved petroleum plume. As noted above, MTBE concentrations have been detected from Top Filling Station well VW-3B at concentrations as high as 440,000 µg/1, from Top Filling Station well MW-6A at concentrations as high as 43,000 µg/1 and a trend of increasing MTBE concentrations has been reported from the Knowles/Roek Property well MW-14 (located approximately 90 feet east-southeast of the site) since March 2001. 6. AGE discussed the site conditions that are conducive for a groundwater extraction pump- and-treat system. AGE has identified the First Water Zone at depths between 30 feet bsg and approximately 55 feet bsg, and has submitted a theoretical capture zone analysis to the SJCEHD. 7. Mr. Henderson advised that AGE needs to submit a site conceptual model for the Top Filling site, and additional lateral and vertical investigation (i.e. multi-level monitoring wells) will be necessary to complete site assessment. As a result of the above referenced meeting, AGE recommends the preparation of an interim remediation work plan for ground water extraction(pump-and-treat)to halt further down-gradient migration of the plume of contamination.Upon SJCEHD approval,AGE will submit a detailed cost estimate to the Underground Storage Tank Cleanup Fund (USTCF) for pre-approval. Advanced GeoEnvironmental,Inc.