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CVAT L A S S O C I A T E S I N C watertight, flush-mounted, traffic-rated vault. Monitoring well construction details are depicted on the well logs contained in Appendix A. 2_4 Well Surveying and Development On January 26, 2005, an ATC field specialist surveyed the locations and elevations of wells MW7 and MW8. The surveyed well casing elevations are indicated in Table 1. The wells are scheduled to be surveyed to Geotracker standards in April 2005 and will be immediately uploaded and included in the next quarterly report. On January 26, 2005, the two new monitoring wells were developed by pumping to remove sediment that may have accumulated in and around the well casing during installation. Between 18 and 25 gallons of groundwater (at least ten well volumes) were purged during development of each well. Groundwater purged from the wells was contained in DOT-approved 55-gallon drums and stored on-site pending proper disposition. Monitoring well development information is included in Appendix B. 2_5 Groundwater Sampling and Analyses On January 26, 2005, groundwater samples were collected from wells MW 1 through MW3 and MW5 through MW8. Well MW4 was under water and deemed inaccessible during the groundwater monitoring event. Prior to collection of groundwater samples, the depth to water was measured in the remaining wells and the pH, electrical conductivity, and temperature were measured in groundwater purged from the monitoring wells and recorded. A minimum of three well casing volumes were purged from wells MW1 through MW3, MW5, and MW6, and as described in Section 2.4, at least ten well casing volumes were purged from wells MW7, and 6d MW8 prior to sampling. The wells were allowed to recover and samples were collected from each well using disposable polyethylene bailers. Field purge logs are presented in Appendix B. L The groundwater samples collected from each well were submitted to State-certified Argon Laboratories (Environmental Laboratory Accreditation Program Certification. No. 2359) in Ceres, California for chemical analyses of total petroleum hydrocarbons quantified as gasoline (TPHg) utilizing EPA Method 8015B; benzene, toluene, ethylbenzene, and xylenes (BTEX) utilizing EPA Method 802113; and methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether �,. (ETBE) di-isopropyl ether (DIPE), tertiary amyl ether (TAME), tertiary butyl ether (TBA), 1,2- dichloroethane(1,2-DCA), and 1,2-dibromoethane (EDB) utilizing EPA Method 8260B. 3.0 ANALYTICAL RESULTS TPHg and BTEX constituents were detected in the groundwater samples collected from wells -• ,-, MW2 and MW3. Toluene was detected in the groundwater sample collected from well MW2 at a NOW/ very low concentration. Only benzene exceeded the maximum contaminant level (MCL) of 1.0 micrograms per liter (gg/L). MTBE was detected in the groundwater samples collected from L SAEnviromental\17861-Glover\REP0RTS\2005QMR1 andwellinstal lreport.doc 4