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The drilling contractor will install the deep monitoring well in an 8-inch diameter sod boring, drilled 1 through the conductor casing with hollow-stem augers to a total depth of approximately 52 feet The deep well will consist of a 10-foot section of two-inch diameter, Schedule 40, flush-threaded and machine-slotted (0 020-inch) PVC well screen spanning from approximately 42 to 52 feet bgs Blank PVC casing will thread into the top of the well screen and extend to the surface A filter pack of Monterey#3 graded and washed sand will be placed around the well screen and approximately two feet above the top of the screened interval (i e , 40 feet bgs) Overlying the sand pack, two feet of bentonite pellets will be placed within the annular space between the borehole and the well casing Over the hydrated bentonite, a surface seal of neat cement grout will be installed with a tremae pipe The top of the well will be secured with a water-tight locking cap and a traffic-rated, flush-mount street box 3 2 3 Soil Sampling and Analysis During drilling, undisturbed sod samples will be collected at 5-foot intervals using a modified California split-spoon sampler, lined with two-inch diameter by six-inch long stainless steel sample sleeves During the drilling of the deep well, the sods will be continuously cored between 40 and 52 feet bgs, to confirm conductor placement and well construction A field geologist will log each of the undisturbed soil samples and the continuous core for hydrogeologic and lithologic characteristics according to the Unified Soil Classification System, and screen each sample for any organic vapors using a photoionization detector(PID) Since the extent of impacted sod is mostly defined, additional sod samples will not be submitted for laboratory analysis If any soil samples exhibit evidence of impact (e g , petroleum odor, discoloration or PID reading), they may be submitted for analysis Field observations and sample selection will be reviewed with the EHD inspector, prior to sample submittal to the lab Any submitted sod samples will be sealed with Teflono film and plastic end caps, labeled, packaged in an iced cooler and transported with chain-of-custody documentation to a state of California-certified hazardous waste testing laboratory for analysis Each of the sod samples will be analyzed for TPH-as-diesel, TPH-as-gasoline, and BTEX by EPA Method 8020/8015M, and for MTBE, DIPS, ETBE, TAME, TBA and 1,2-DCA by EPA Method 8260B i11