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C A M B R I A Ms.Lori Duncan November 18,2005 During September 1997, Cambria installed monitoring wells MW-4 through MW-7. Cambria's November 11, 1997 Site Investigation Report/Quarterly Monitoring Report — Fourth Quarter 1997 describes this investigation. 2000-2001 Cone Penetration Test Borings and Well Installation: During May 2000, Cambria drilled two cone penetration test borings (SB-5 and SB-6), and during November 2001, installed groundwater monitoring wells MW-10 and MW-11. Proposed wells MW-8 and MW-9 could not be installed at the original proposed locations in Pacific Avenue due to the presence of utilities. Boring SB-5 contained up to 6,020 ppm TPHg and 19.3 ppm benzene. No TPHg was detected in soil samples from boring SB-5 at or below 60.5 fbg, and no benzene was detected at or below © 80.5 fbg, vertically delineating these constituents in soil in the former UST area. Methyl tertiary butyl ether (MTBE) was not detected in soil samples from boring SB-5. No TPHg, benzene, or MTBE was detected in soil samples from boring SB-6 or well borings MW-10 and MW-11. TPHg and benzene were detected in groundwater samples from boring SB-5 at concentrations up to 283,000 and 51,900 ppb,respectively. The highest concentrations were detected at 50 fbg,and concentrations dropped off dramatically with depth in boring SB-5. No fuel oxygenates were detected in boring SB-5. TPHg and benzene were detected in groundwater samples from boring SB-6 at concentrations up to 1,670 and 37.6 ppb, respectively. MTBE and di-isopropyl ether (DIPE) were detected at 50 fbg at concentrations of 33.8 ppb and 18.6 ppb, respectively. No other oxygenates were detected in boring SB-6. Cambria's January 11, 2002 Fourth Quarter 2001 Groundwater Monitoring/Site Investigation Report and Receptor Survey presents investigation results. 2001-2002 Receptor Survey: During 2001, Cambria conducted a receptor survey. California Department of Water Resources records identified four water production wells (three domestic wells and one municipal well) within the study area. The approximate well locations are plotted on Figure 1. The closest well to the subject site is a domestic well located approximately 450 feet northwest of the site. A second domestic well is located 850 feet northeast of the site. During 2002, Cambria performed a door-to-door survey to determine the status of these two wells. During the survey, Cambria spoke to residents at both locations and confirmed that neither of these domestic wells is in use. Both residences are serviced by City water, and the wells are either not functioning or not being used. Table 1 presents the well survey data. No surface water bodies were identified within the survey area. Cambria submitted the results of the receptor surveys in our January 11, 2002 Fourth Quarter 2001 Groundwater Monitoring/Sire Investigation Report and Receptor Survey and January 6, 2003 Site Investigation and Third Quarter 2003 Groundwater Monitoring Report. , 2002 Well Installation: During August 2002, Cambria installed wells MW-8 and MW-9 across Pacific Avenue from the subject site. No TPHg, benzene, toluene, ethylbenzene, and xylenes (BTEX), or MTBE was detected in well borings MW-8 or MW-9. Cambria details this 3