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prior to arriving, and before leaving the site Soil samples were collected by advancing the augers to the desired sampling depth interval, and driving a split spoon sampler equipped with clean brass liners The sampler was then retrieved and dissembled, and the soil samples retained for chemical analysis were cut from the soil filled acetate liner, sealed with foil and plastic endcaps, labeled, logged onto chain-of-custody forms and placed in a chilled ice chest The boreholes were logged using the Unified Soil Classification System under the supervision of a registered geologist Additional lithologic information was collected to describe the subsurface geology The samples were continuously collected at intervals of obvious contamination and at stratigraphic features of interest Three groundwater monitoring wells were installed The wells were cased with Sch 40 PVC casing, threaded together, glues were not used The slotted interval was cased with 0 020 inch slot and the annular space around the slots was backfilled with a 2/12 size sand Previous experience has shown this to be a reliable well design in fine grained and stratified depositional environments Final well design was modified to the site specific conditions encountered in the borehole during drilling Once the aquifer strata has been defined, the casing was lowered to the bottom of the borehole, leaving a slotted interval above the occurrence of groundwater to observe for floating product The sand pack was placed to a point about two feet above the slots A bentonite sea[ was placed atop the sand pack, and a cement grout seal placed atop the bentonite using a tremae line, filling from the bottom to top of the borehole A traffic rated well head access box and security device completed the well The location for monitoring well MW-3 was adjusted in the field after discussions with the PHS-EHD representative The location was moved about 15 feet closer to the former underground storage tank location from the initially proposed location Well Head Survey All wells will be surveyed to mean sea level using a known datum This allows accurate measurements and groundwater gradient to be calculated Mo!]itonng Well Sampling and Develo ment All monitoring wells were developed to remove the drilling muck, grade the sand pack and provide a more complete hydraulic connection to the aquifer The well volume was calculated and a number of those volumes were removed until the water clears and the amount of sand pumped was minimal The well was then allowed to recover for at least 72 hours prior to sampling A log of the development was kept for each well Each monitoring well was sampled Each borehole was advanced into the aquifer and temporarily cased Each monitoring well was purged using calculated well volumes based upon the depth to water in each casing Depth to groundwater measurements were made to the nearest one-one hundredth of one foot, and also checked for the presence of separate phase product As each purge volume was removed, measurements of pH, electrical conductivity and temperature were taken until these parameters stabilized, which is interpreted to indicate aquifer water entering the casing The sample was carefully collected with a clean bailer and poured into the appropriate laboratory prepared container with minimum cavitation Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest Upon completion of well sampling, the well was closed and locked and the sampler moved to the next sampling point Haley Wells Project No 4111 Page 2