ARCHIVED REPORTS_XR0005580 - Laserfiche WebLink

Home Browse Search

' GeologrwfTechinics Inc Page 2 Groundwater Monitoring Report Project No 640 2 August 18, 2000 ' The groundwater gradient flow direction at this site has been consistent for the four events that it was measured ' Figure 2 is a groundwater gradient map for the May 1, 2000 event Table 1 in Appendix A contains the groundwater elevations and gradients to date ' 1.2 Groundwater Sampling Procedure ' On May 1, 2000, Del-Tech Geotechnical Support personnel arrived on-site, opened 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 Q 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% 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) 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 vial) prior to collecting the analytical sample Extreme 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 lee chest cooled to 4°C for transport to the laboratory ' The sampling technician wore disposable gloves while collecting all samples A chain of custody document, listing all samples collected and their intended analyses, ' accompanied the samples from the field to the laboratory, thereby providing a means to track their movement and insure their integrity 1