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Since groundwater is anticipated at approximately 50 feet bgs, the well screen intervals will extend' from approximately 40 to 60 feet bgs. Blank PVC casings will thread into the tops of the well screens and extend to the surface: Filter packs of Monterey#3 graded and washed sand will be placed in the annular spaces between the boreholes and well casings and approximately two feet above the tops of the screened intervals (Le., 33 feet legs). The ells will be surged and purged by the driller,following the placement of the sand packs and prior to the installation of the well seals. Periodic surging and purging of each well will continue, until at lest five well volumes have been removed; Overlying the filter packs, two feet of hydrated bentonite chips will be placed within the annular spaces between the boreholes and the well casings (i.e., 36 to 33 feet fags). Over the hydrated bentonite, surface seals of neat cement grout will be installed. The tops of the wells will be secured with Watertight caps and traffic-rated,flush-mount street boxes, i licensed land surveyor will survey each of the newly-installed wellheads. The surveyor will measure the elevations of the tops of well casings to the nearest 0.01 foot, referenced to benchmark. The locations of the wells and other site features will also be surveyed. ;3.x.2 foil tom lln and final ss During drilling, undisturbed soil samples will be collected at five-Brat intervals lasing a modified California split-spoon sampler, lined with two-inch diameter by six-inch long brass or stainless steel sample sleeves. A field geologist will log each sof the !undisturbed soil samples for hydrogel logic and lithologic characteristics according to the Unified Soil Classification System, and screen each sample for any organic vapors fusing a ph atoioni ation detector (PID), To further evaluate the lateral extent of impacted soil, rap to three samples per boring will b ' submitted for laboratory analysis. `tentatively, the soil samples collected at 20,45 and 60 feet bg will be submitted for analysis. Additional scall samples may be submitted for analysis„ if necessary to'characterize isubsurface conditions, Field observations and sample selection will be reviewed with the EHD inspector, prior to sample submittal to the lab; 9