ARCHIVED REPORTS_XR0012025 - Laserfiche WebLink

Home Browse Search

' 08 July 1999 AGE-NC Project No 95-0130 Page 2 of 5 ' 2 2 GROUND WATER SAMPLING Following well purging, ground water levels in monitoring wells MW-1 through MW-5, VW-IC, ' VW-2A and VW3-A achieved a minimum of 80 percent recharge prior to sample collection Ground water samples were collected from the purged wells utilizing new, disposable polyethylene bailers and three EPA-approved 40-m1 VOA vials containing 0 5 ml 18% hydrochloric acid as a sample preservative Care was taken to ensure that visible air bubbles were not present in the vials after filling and capping Ground water sample containers were labeled with the well designation, date, time, and sampler's initials 23 LABORATORY ANALYSIS OF GROUND WATER SAMPLES ' Eachroue g d water sample was Iogged on achain-of-custody form,placed in a chilled container and ' transported to a California Department of Health Services (DHS)-certified laboratory for analysis in accordance with • EPA Method 8015M for total petroleum hydrocarbons quantified as gasoline (TPH-g), • EPA Method 8020 for volatile aromatic compounds benzene, toluene, ethyl benzene and ' xylene (BTEX) with methyl-tertiary butyl ether (MTBE), and • EPA Method 8260M for tertiary butanol (TBA), di-isopropyl ether (DIPS), ethyl tert butyl ether(ETBE), tert amyl methyl ether(TAME) and MTBE 3.0. FINDINGS AGE determined ground water flow direction and gradient from the field data collected on 26 March 1999 Laboratory analysis detected TPH-g and BTEX in eight ground water samples, fuel oxygenated compounds were detected in five ground water samples ' 31 RELATIVE GROUND WATER ELEVATION AND GRADIENT The depths to ground water from wells MW-1 through MW-5, VW-IC, VW-2A and VW-3A were measured between 3 7 3 8 and 3 8 76 feet below the tops of the well casings Ground water elevations at the site were calculated to be between 21 63 feet and 22 46 feet below mean sea level, ground water elevations are depicted in Figure 3 Ground water elevation at the site increased an average I 79 feet between the December 1998 and the March 1999 ground water monitoring events, a trend Adranced GeoEmironmental,Inc I