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Monitoring Well Installation Procedures The groundwater monitoring wells will be installed using hollowstem drilling methods Each will be installed in a borehole to the depth shown The wells will be installed under approved HD permits and the work will be supervised by a registered geologist (see detail drawing) The site has been logged and the site stratigraphy has been mapped Borehole lithologic logging will be performed to verify strata contacts on a limited as needed for installing the well slots at the desired depth interval The boreholes will be advanced by drilling to the desired depth with pre-cleaned hollowstem augers Augers, sampling tools and rods will be cleaned after each borehole and prior to leaving the site Soil logging for contact verification will use the Unified Soil Classification System (USCS) using a split-spoon soil sampler advanced at the desired depth A geologist will log the soil and retain samples as needed If soil samples are retained, they will be collected in clean brass liners completely driven to completely fill the liners in the sampler drive The soil sample will be takers from the split-spoon, sealed with Teflon paper or foil, capped with plastic endplugs, logged onto a chain-of-custody form and packed of crushed ice for shipment of the laboratory Each well will be constructed in the appropriate borehole as shown The wells will use two-inch diameter Schedule 40 PVC casing as shown Casing will be joined using threaded joints and glues will not be used The casing will be cut to the required length and threaded together with a bottom casing endpiug and lowered through the hollowstem auger The slotted intervals will use factory machine cut 0 020-inch slots Once the well casing is set, an aquarium (or equivalent) sand pack will be placed in the casing annular space using the hollowstem auger as a tremie pipe The sand pack will be placed to a level about 2-feet above the slotted interval A bentonite clay spacer will be placed atop the sand pack and hydrated prior to the cement grout placement to prevent grout invasion into the sand pack A cement grout seal will then be placed atop the bentonite clay and raised to the surface from the bottom to the top of each annular space using the hollowstem augers as a tremie pipe A traffic rated locking well vault box will complete each monitoring well head surface access Proposed Groundwater Monitoring Well Details Prol No 4233-3 Stefanos Gasoline Dimensions as shown 1419 Charter Way Date Nov 2003 Wnght Environmentai Services, Inc. Stockton, CA Tracy, CA Figum.T. part 2 of 2