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bottom of the boring to approximately 1-foot above the well screen A 2- <br /> foot thick hydrated bentonite layer separates the sand from the overlying <br /> cement surface seal The cement sanitary surface seal in each of these <br />' wells was placed by tremie pipe <br /> The wellheads of all ten wells/piezometer are secured with locking <br />' wellplugs beneath at-grade traffic-rated vaults <br /> 2 -2 Monitoring Well Dcve$lQpinent <br />' wells MW-11 and MW-12 were developed on the date of the <br /> Monitoring P <br /> drilling using surge block agitation and bailer evacuation in order to settle <br /> 1 the sandpack prior to placing the bentonite and cement seals Additional <br /> water was removed prior to the sampling of each well in order to further <br />' clarify the groundwater produced in the wells In total, at least ten times <br /> the volume of the well casing in the saturated screened interval plus o n e <br /> total volume of water in the well casing was removed during the <br />' development process <br /> Monitoring wells MW-13 through MW-15 and piezometers P-1 through P-5 <br /> were developed at least 72 hours following completion of the <br /> wells/piezometers using surge block agitation and evacuation with pumps <br /> and/or bailers At least ten well casing volumes of groundwater were <br /> removed from the wells/piezometers during development Upon <br /> completion of the well development, the water produced in all ten <br /> Iwells/piezometers was relatively clear <br /> L3 Monitoring Well Sampling <br />' <br /> Between March 16 and 22, 2000, ASE associate geologist Ian Reed <br /> collected groundwater samples from each monitoring well for analysis <br /> Monitoring well MW-5 contained 020-feet of free-floating hydrocarbons, <br /> and therefore was not sampled A sheen was present on the surface of <br /> groundwater in monitoring well MW-6 and piezometer P-5 <br /> Prior to sampling, the wells were purged of four well casing volumes of <br /> groundwater using any combination of Purger pumps, Grundfos pumps <br /> and/or dedicated bailers The pH, temperature and conductivity of t h e <br /> purge water were monitored during evacuation, and samples were n o t <br /> icollected until these parameters stabilized Samples were collected from <br /> the wells using pre-cleaned dedicated polyethylene bailers The <br /> groundwater samples for volatile compounds were decanted from the <br /> bailers into 40-m1 volatile organic analysis {VOA} vials, preserved with <br /> Franks One Stop Report - May 2000 <br /> -10- <br />