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28 January 1998 AGE-NC Project No. 96-0232 Page 4 of 6 water after washing with a solution of Alconox. All hollow stem augers will be steam-cleaned prior to advancement in each borehole. 3.3. WELL COMPLETION Each soil boring will be dual completed as ground water monitoring wells by utilizing 2-inch diameter, schedule 40, blank PVC casing and 2-inch diameter screened casing (0.020-inch slot). A PVC casing will be emplaced through the hollow stem of the augers to the total depth of the boring. The augers will be incrementally raised as a#3 Lonestar Lapis Luster sand (filter pack) is slowly poured down the annulus between the well casing and the inner wall of the auger. The filter pack will be placed from the bottom of the screen to a point approximately 2 feet above the top of the screen. Following filter pack placement,a surge block will be inserted into the PVC casing and lowered then raised (surged) repeatedly for approximately 10 minutes. Thereafter, a minimum of three feet of bentonite coded pellets (annular seal)will be placed above the filter pack as an anular seal between a shallow screened interval and the deep screened interval. The shallow screened interval will next be installed by placing PVC well casing through the augers to the top of the annular seal. The filter pack will be placed in a similar manner as above and a surge block will be used for approximately 10 minutes. Three feet of bentonite chips will be placed above the shallow screened filter pack and hydrated with clean tap water. Finally, the anular space will be sealed with Portland type II cement. Proposed ground water monitoring well construction diagram is included as Figures 3. The design of each monitoring well may be modified based upon field observations and site conditions. Monitoring wells will be developed utilizing a submersible pump. Water will be purged from each well so that each well is essentially sediment free.Purged ground water will be stored on-site in DOT drums in an area lacking public access. A reference point will be marked on the top of each well head, and surveyed by a licensed surveying engineer the to the nearest 0.01 foot to determine the elevation relative to a surveyed benchmark. 3.4. LABORATORY ANALYSIS Selected soil and ground water samples will be analyzed for MTBE in accordance with EPA methods 8260. Laboratory reports of soil and ground water analysis;testing methods, laboratory quality assurance/quality control (QA/QC)reports, and sample chain of custody documentation will be included with a report of findings. Advanced GeoEnvironmenta 1,Inc.