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Ms. Victoria McCartney May 16, 2006 Page 2 of 4 • At least three times the volume of standing water was purged from the monitoring well. • After the purge cycle was compete, a groundwater sample was collected for analysis with a disposable polyethylene bailer and transferred to the appropriate laboratory-supplied sample container. Pre-preserved laboratory-supplied containers were used for sample collection. IGroundwater monitoring and sampling field data sheets are presented as attachments to the G-R monitoring report, provided in Attachment 1. Subsequent to collection, samples were packed on ice, cooled to approximately 4°C, and shipped under appropriate chain-of-custody protocols for analysis to Lancaster Laboratories (Lancaster) of Lancaster Pennsylvania, a California-certified analytical laboratory. Analyses included the following parameters: • total petroleum hydrocarbons in the gasoline range [TPH-G (C6-C10)], total petroleum hydrocarbons in the diesel range [TPH-D (C10-C28)], total petroleum hydrocarbons in the motor oil range [TPH-MO (C16-C36)], and methanol by United States Environmental Protection Agency (USEPA) Method 8015; + benzene, toluene, ethylbenzene, and total xylenes (BTEX)by USEPA Method 8260B; and • t-butyl alcohol (TBA), methyl tertiary butyl ether (MTBE), di-isopropyl alcohol (DIPE), ethyl . tertiary butyl alcohol (ETBE), tertiary amyl methyl ether (TAME), 1,2-dichloroethane (1,2- DCA), ethylene dibromide (EDB), also known as 1,2-dibromoethane, and ethanol by USEPA Method 826013. A quality assurance/quality control sample inclusive of a trip blank was also submitted for laboratory r analysis. The laboratory supplied trip blank accompanied the sample delivery group. Trip blank samples were collected at a rate of one per 20 samples for TPH-G, BTEX, and MTBE. Analytical results for the quarterly groundwater monitoring event are included as attachments to the G-R monitoring report, provided in Attachment 1. Purge water and equipment decontamination water generated during the sampling event was containerized for off-site disposal. Monitoring Results Depth to water measurements were subtracted from the surveyed top-of-casing elevation to calculate the I groundwater elevations for each monitoring well. Depth to water and the calculated groundwater elevations are presented in Table 1 of the G-R monitoring report (Attachment 1). Calculated groundwater elevation data were then used to construct the groundwater potentiometric map (Figure 1 of the G-R monitoring report, provided in Attachment 1). Separate phase hydrocarbons (SPH) were not observed during gauging of the monitoring wells. Groundwater elevations at the site ranged from 11.11 (MW-16) to 11.91 (MW-5) feet below mean sea level. Groundwater elevations across the site have increased an average of 1.90 feet since the fourth quarter of 2005. The groundwater flow direction was generally to the southeast, as illustrated on the potentiometric map (Figure 1 of the G-R monitoring report, provided in Attachment 1) and the horizontal 11362822.doc BLASLAND, BOUCK& LEE, INC. engineers,scientists,economists i