ARCHIVED REPORTS_XR0006948 - Laserfiche WebLink

Home Browse Search

Firstuarter 2001 Ground Wa Q ter Monitoring Report Cleanea and Abatement Order No 5-00-707 EAI Project No 1232 2 0 FIELD INVESTIGATION 21 Ground Water Elevation Survey On March 27, 2001, all new well casing elevations (see Section 1 1 2) were surveyed to the established referenced datum point for the project ' 2.2 Ground Water Sampling On March 27, 2001, prior to purging or sampling activities, depth measurements to fluid levels ' were obtained by EAI from all monitoring wells associated with the Wards (MW-1 through MW-7) and Unocal (MW-10 through MW-25D) sites Depth measurements were obtained using an interface probe accurate to 0 01 foot (see Table 2) No free-product was detected in any of the wells The water level measurement for each well was converted to mean sea level (MSL) datum by subtracting the measured water level for each ' well from its respective "top of well casing elevation" datum (see Table 2) On March 27 and 28, 2001, ground water samples were collected by EAI from all ground water monitoring wells associated with the Wards and Unocal sites Prior to sampling, the wells were purged using a Grundfos MP-I submersible pump Temperature, conductivity, pH, and turbidity were recorded to evaluate the effectiveness of purging activities (see Appendix A) The wells were sampled in the order that purging activities were completed As requested by the RWQCB, all wells associated with the Wards and Unocal sites were to be sampled using a point source bailer Mr Marty Hartzell with the RWQCB was present during sampling of well MW-7, the first well sampled during this sampling period Well MW-7 was sampled using a point source bailer After reviewing the sampling procedure in the field with Mr Hartzell, it was determined that sampling using disposable bailers was as representative as the point source bailers, and therefore, all remaining water samples were obtained from dust below the water surface using Voss Technologies disposable bottom bailers equipped with ' volatile organic compound sampling tips Use of these bailers precludes the potential for cross- contamination ' Each water sample was sealed in three 40-milliliter volatile organic analysis (VOA) vials with Teflon septa lined lids The VOA vials were completely filled so that no head space existed between the sample and the lids The samples were labeled with the sample point identification, preservative added, if any, date, time, and EAI project number, and immediately placed into a chilled ice chest The samples were kept chilled until delivered to the laboratory for analytical testing All samples were logged on a chain of custody record form (see Appendix B) 0HL1 MM0171 4 ' ENVIRONMENTAL AUDIT, INC