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18 February 2003 <br /> E AGE-NC Project No 96-0229 <br /> Page 3 of 9 <br /> 2 13 Equipment Decontamination <br /> Prior to soil boring advancement,the hollow stern augers were pressure washed Sampling tools and <br /> brass sleeves used for sample collection were thoroughly washed with a solution of Alconox, and <br /> were thoroughly rinsed with clean tap water pnor to each sampling sequence Following drilling <br /> activities, rinseate generated from decontaminating the equipment was placed in properly labeled <br /> DOT-approved model 17H 55-gallon drums and was stored on-site in an area lacking public access <br /> 2 1 4 Monitoring Well Completion <br /> 1 Soil bonngs MW-11 and MW-12 were single-completed as groundwater monitoring wells utili/ing <br />` an assembly of 2-inch diameter, schedule 40, blank polyvinylchlonde (PVC) well casing and <br /> perforated, 2-inch diameter PVC well casing (0 020-inch slot) Each well was installed by placing <br /> I the PVC well casing assembly through the hollow stem of the augers to the total depth of each <br /> i boring The augers were incrementally raised as No 2/12 Lonestar Lapis Luster sand (filter pack) <br /> was slowly poured down the annulus between the well casing and the inner wall of the hollow stem <br /> i auger The filter pack was placed adjacent to the screened casing from the bottom of the boring to <br />` a point approximately two feet above the top of the screen, following filter pack placement, a surge <br /> block was inserted into the well casing and was alternately raised and lowered (surged) repeatedly <br /> for approximately 20 minutes Approximately three feet of bentonite pellets (annular seal) were <br /> placed above the filter pack and€.ere hydrated with clean tap water The remaining annular space <br /> was backfilled with portland cement (grout seal) As-built momtonng well-construction diagrams <br /> are included as Figures 3 and 4 <br /> 2 1 5 Monitoring Well Development <br /> On 04 November 2002, monitoring wells MW-11 and MW-12 were developed utilizing a stainless <br /> steel hand bailer and a two-stage submersible pump Groundwater was purged from each monitoring <br /> well until groundwater was visually sediment free,approximately 25 gallons ofwater were removed <br /> from each well Purged ground water was containerized in properly labeled D O T -approved model <br /> 1 7117 JJ-gd11011 UrU111h d1IU WdS btUIVU U11-bill: III do drUd IdLling pUUII(. dL(.eSS <br /> 2 1 6 Surveying of Monitoring Wells <br /> On 22 November 2002, a California state-licensed survey engineer from Baumbach & Piazza, Inc <br /> surveyed a reference point on the casing top of wells MW-11 and MW-12 to the nearest 0 01-foot <br /> F <br /> Advanced GeoEnvironmental,Inc <br /> I <br />