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' Geoloyw lTechnxs Inc Page 2 Groundwater Monitoring Report Project No 640 2 January 31,2000 ' The groundwater gradient flow direction at this site has been consistent for the two events that it was measured During the July 26, 1999 monitoring event the groundwater gradient ' was N70°W with a slope of 0 0014 ft/ft Figure 2 is a groundwater gradient map for the November 24, 1999 event Table I in ' Appendix A contains the groundwater elevations and gradients to date 1.2 Groundwater Sampling Procedure ' On November 24, 1999, Del-Tech Geotechnical Support personnel arrived on-site opened pP p the wells, and measured the depths to water with an electrically actuated sounding tape The ' water level readings were recorded to an accuracy of 0 01 foot In wells where free-floating product is suspected, a clear disposable bailer was used to gauge the interface During this ' monitoring free product was not observed Stagnant water in the well casing was purged using a centrifugal pump, as recorded on the ' field logs (Appendix C) The rate of well purging was monitored The wells were purged of at least three casing volumes and until the groundwater parameters (temperature, conductivity, and pH) had stabilized (Appendix C), indicating that water representative of actual aquifer conditions was entering the well Groundwater parameter stabilization was characterized by three successive readings within 10% I Before a sample was collected, the well's water level was allowed to recharge to at least 80% of the initial level All water removed from the monitoring well and not used as a sample, was placed in a 55 gallon DOT (Department of Transportation 17-H) approved container that was properly labeled and temporarily stored on-site A stainless steel bailer was used to collect each sample Bailer cleanliness was assured by collecting a bailer blank (pouring distilled water through the bailer and collecting it in a VOA via]) prior to collecting the analytical sample IExtreme care was exercised while collecting samples to prevent agitation of the water contained in the bailer Water samples were transferred from the bailer into 40-m1 VOA vials, preserved with hydrochloric acid, using a bottom-emptying device that minimizes sample aeration during transfer of the sample All samples were checked for headspace bubbles, labeled, inserted into foam holders, and placed in an ice chest cooled to 4°C for Itransport to the laboratory The sampling technician wore disposable gloves while collecting all samples