ARCHIVED REPORTS_XR0012667 - Laserfiche WebLink

Home Browse Search

KLE1NFELDER 4 RESULTS This section presents the ground water elevation data and the analytical results for ground water and vadose zone samples collected during the assessment activities described in Section 3. Some of the data collected and presented in previous investigations (Table 1) are also summarized in this section for comparison. 4.1 WA'T'ER LEVELS Water levels were measured on each sampling date. Using the surveyed casing elevations for the eight wells (Welt Master List in Appendix A), ground water elevations were computed. The water depths and elevations for each sampling date are presented in Table 2. The data for the past year are contoured on Plates 7 through 10. The contour maps indicate that the shallow zone of ground water at the site has been approximately 26 to 30 feet above mean sea level (30 to 34 feet below ground surface) over the past year and that the ground water gradient has been approximately 1% to the south-southwest. From our observations,ground water gradient appears to be consistent 4.2 GROUND WATER ANALYSIS The analytical results for the ground water sampling performed to date, including the last three quarterly sampling events,are presented in Table 3. The purge data sheets, chain-of- custody forms and original laboratory reports for the last three sampling events are included in Appendix B. Original laboratory reports for data collected prior to November 1987 are contained in previous Kleinfelder reports,summarized in Table 1. The data presented in Table 3 indicate that: o benzene, toluene, ethylbenzene, and xylene were not detected in water samples collected from MW-1 through MIA'-8 during the last two quarterly --- -- -- -- -- - ---sampling-rounds,-except-for-1.3-ug/l of toluene detected-in-a-sample _- MW-1 during February 1988 and 1.3 ug/I of toluene in a sample from MW-2 during May 1988. (The detection limit for toluene is 1.0 ug/1). w. 113-88-908 9