SITE INFORMATION AND CORRESPONDENCE

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Geological Technics Inc Page 2 Former Moresco Property Project No.251.2 December 20,1995 2.0 ADDITIONALLY PROPOSED WORK -2.1 Installation of Vapor Extraction Wells Because preliminary information suggests that this site exhibits favorable conditions for remediation by soil vapor extraction (SVE) technology, we recommend that the feasibility of using SVE technology to mitigate the vadose zone contaminants be evaluated by a vapor extraction pilot test. Therefore while the drilling equipment is onsite we propose to install two permanent vapor extraction wells and convert the proposed exploratory borehole to the north into a multilevel soil vapor extraction monitoring well for conducting the pilot test. After the test is concluded the wells would'be in place for use during the remedial program if it is confirmed that SVE technology is an appropriate remedial technology. Geological Technics Inc. recommends that the 2 vapor extraction..wells be installed adjacent to the former point of release where the UST' was located (adjacent to proposed MW-1 and existing SB-1/1A) and be constructed as shown in the table below. Drilling, sampling, and well construction will be conducted according to protocol established for this site. Vapor Extraction Well Construction Well Details Well Diameter Screened Filter Pack Bentonite Cement Interval pea gravel Annular Grout, 0.040" (ft) (ft) Seal (ft) (ft) VEW-1 4" 54.5-67 52.5-67 49.5-52.5 0-49.5 VEW-2 4" 30-40 28-40 25-28 0-25 Multilevel Vapor Extraction Monitoring Well Construction Well Details Well Diameter Screened Filter Pack Bentonite Cement Interval #3 sand Annular Grout. 0.020" (ft) (ft) Seal (ft) (ft) VEMW-1 1" - - 20-22 0-20 1" 22.5-23.5 22-24 24-37 - lit 37.5-38.5 37-39 39=58 - 1" 58.5-59.5 58-60 60-77 - 1" 77.5-78.5 77-79 79-90 -