ARCHIVED REPORTS_XR0010433 - Laserfiche WebLink

Home Browse Search

IFel"NUORc Groundwater samples were collected from wells MW1, MW2, and MW3 on May 29, �a 1996 The samples were analyzed for TPH-G, TPH-D, TPH as JP4}et fuel, MTBE, and BTEX Analytical results for the groundwater samples identified no detectible concentrations of these ' constituents at or above laboratory detection limits in MW1 and MW3 However, the samples from MW2 reported TPH-G at 149 micrograms per liter (µg/L), benzene at 0 76 lig/L, xylene at 0 76 µg/l, and MTBE at 149 µg/L 3.0 GROUNDWATER SAMPLING ' �tl G� The following sections describe the groundwater sample collection, groundwater laboratory analytical results and waste storage and disposal Samples were collected according �h to the Sampling and Analysis Plan submitted in Versar's Site Investigation Workplan, dated August 2, 1995, and Workplan Addendum, dated May 10, 1996 Ift 3.1 Groundwater Sample Collection On December 31, 1996, groundwater samples were collected from groundwater [5 monitoring wells MWI, MW2, and MW3 at the Site Prior to purging and sampling, depths to groundwater in monitoring wells MW 1, MW2, and MW3 were recorded at 42 87, 42 87, and 42 55 feet bgs, respectively Each monitoring well was purged of approximately three casing lidp volumes of water, the water level was allowed to recover to at least 80 percent of the pre-purge level, and then the wells were sampled During purging activities, the pH, temperature, and conductivity of the purged water were monitored and recorded at regular intervals to assess the influx of representative formation water into the well Data collected prior to and during purging and sampling were recorded on monitoring well purge tables included as Appendix A Samples were collected, placed in containers, preserved, and analyzed within the time constraints consistent with applicable regulatory agency requirements Samples were tracked S using V ersar's chain-of-custody forms The sampling team maintained custody of the samples ' from the time of collection until submittal to the laboratory C3.2 Groundwater Sample Analytical Results Three groundwater samples were collected and submitted for laboratory analysis Each sample was analyzed by Excelchem Environmental Labs, California certification#2119 Analytical results for this and the two previous quarters are presented in Table 2 of this report I MWl, MW2, and MW3 were analyzed for TPH-JP4, BTEX, and MTBE Analytical results for the groundwater samples identified no concentrations of TPH-JP4, BTEX, and MTBE at or above laboratory detection limits in MW 1 Concentrations of xylenes and a concentration of ` benzene equal to the detection limit were reported in MW3 MW2 contained concentrations of H 1PROJECTS10SA1STOCKTONI3RDIREPORT FL 5