SITE INFORMATION AND CORRESPONDENCE

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sampler was retrieved and dissembled, and the soil filled brass liner was sealed with Teflon® paper and plastic endcaps, labeled and logged onto chain-of-custody forms and place in a chilled ice chest. Drill cuttings were placed on plastic and auger decontamination water was stored in DOT approved 17H drums on site until analysis was completed. 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. Soil samples were checked in the field for visible evidence of contamination and a combustible gas meter (Gastech Tanktector) was used to screen soils at each sample interval for the presence of petroleum vapors. The samples were collected at five-foot intervals and at stratigraphic features of interest and/or intervals of obvious contamination. Well Construction One groundwater monitoring well (MW-1) and one vapor extraction well (VW-2) were installed (see attached exploratory boring logs and well construction details). The roundwater well was constructed with Sch. 40 PVC threaded casing; glues were not used. The slotted interval was 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 aquifer depositional environments. This was discussed with the PHS-EHD representative at the site and is consistent with the proposed well construction provided in the workplan. The final well design was modified to the site specific conditions encountered in the borehole during drilling. Once the strata of interest was 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 seal was placed atop the sand pack, and a cement grout seal placed atop the bentonite using a tremie line, filling from the bottom to top of the borehole. A traffic rated well head access box and a locked cap completed the well. The vapor well was constructed with threaded Sch. 40 PVC casing with a 0.10 slot interval, with the annular space filled with clean 3/8 inch pea gravel, to allow for a greater vapor flow from the surrounding soil. A bentonite seal was placed atop the gravel pack, and a cement grout seal placed atop the bentonite using a tremie line, filling from the bottom to top of the borehole. A traffic rated well head access box and a locked cap completed the well. Monitoring Well Development and Sampling The groundwater monitoring well was developed by Blaine Tech Services of San Jose, CA, to remove the drilling muck, grade the sand pack, and to provide a more complete hydraulic connection to the aquifer. A well volume was calculated and a number of those volumes were removed until the water became clear and the amount of sand pumped was minimal. A log of the well development is enclosed. The well was allowed to recover for 24 hours prior to sampling. At the time of sampling, the well was purged using a calculated well volume based upon the depth to water. 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. The well was not surveyed. As each purge volume was removed, measurements of pH, electrical conductivity and temperature were taken until these parameters stabilize, which was Linden School District 2