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Mr. Harlin Knoll August 13,2001 Page 2 A_filter pack of Monterey 43 graded and washed sand will be placed through the hollow stem augers as they are slowly retrieved,and until the sand reaches approximately two feet above the top of the screened interval. The well will be surged and purged by the driller, following the placement of the sand pack and prior to the installation of the well seal. Periodic surging and purging will continue until the amount of suspended sediment in the groundwater decreases and stabilizes and/or until at least five well volumes have been removed. Overlying the sand pack,two feet of hydrated bentonite chips will be placed within the annular space between the borehole and thewellcasing. Over the hydrated bentonite,a surface seal of 20:1 cement;bentonite grout mixture will be installed. The top of the well will be secured with a water-tight cap and a traffic-rated, flush-mount street box. A licensed land surveyor will survey the newly-installed wellhead into the existing monitoring well network. Soil Sampling;and Analysis Turing drilling, undisturbed soil samples will be collected at 5-foot intervals using a modified California split-spoon sampler lined with two-inch diameter by six-inch long brass or stainless steel sample sleeves. A geologist will log each of the soil samples for hydrogeologic and lithologic characteristics according to the Unified Soil Classification System and screen each sample for organic vapors using a photoionization detector (PID). Since the position of the proposed well is outside of the area of the former UST,only three of the soil samples will be submitted for laboratory analysis. The samples collected at the bottom of the soil boring,within the capillary fringe(i.e.,interval of groundwater fluctuation), and from the deepest part of the unsaturated vadose'zone will be submitted for analysis. Additional soil samples may submitted for analysis,if required to adequately characterize the site. Field observations and sample selection will be reviewed with the PHSIEHD inspector,prior to sample submittal to the lab. Each soil sample will be sealed with Teflone 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. The lab will analyze each of the soil samples on a standard turn-around for Total Petroleum Hydrocarbons (TPH)-as-gasoline,benzene,toluene,ethylbenzene, xylenes(BTEX),methyl tertiary butyl ether(MTBE), di-isopropyl ether(RIPE),ethyl tertiary butyl ether(ETBE),tertiary amyl methyl ether(TAME), tertiary butanol (TBA), and 1,2-dichloroethane(1,2-IBCA) by EPA Method 8260B.