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i t� LIGHT, AIR & SPACE CONSTRUCTION ENVIRONMENTAL SERVICES COMPANY State Contractor's License Number 445403 State EPA R.E.A.Number 04072 Office 408-979-1661 Table 1. Groundwater Data in Monitoring Wells,December 2, 2008 Well Number Depth to Top of Casing Groundwater Comments Groundwater(ft) Elevation (ft) Elevation(ft) MW-1 9.40 16.62 7.22 None MW-2 9.41 16.42 7.01 None LA�MW-3 8.70 15.42 6.72 None 5.0 Discussion The soil samples from the soil stockpile show that very low TPHD concentration was detected in p p t composites. TPHG, BTEX, MTBE and fuel oxygenates were not detected to any soil composite samples. TPHG, TPHD, BTEX, MTBE and fuel oxygenates were not detected in any soil IF samples collected from the exploratory boreholes (see Table 3). �I Groundwater data showed TPHG at 69 micrograms per liter (ug/1) in MW-1 and MTBE at 3.99 ug/l in MW-3. No other contaminants were detected in the groundwater samples. The laboratory reported that the TPHG did not match the typical pattern for gasoline. The water sample collected from the on-site drinking water well showed that TPHG,TPHD, BTEX, MTBE and fuel oxygenates were not detected (see Table 4). The USTs reportedly had not been used since about 1985. Soil excavated from the tank pits was placed on a plastic lined pad and allowed to aerate. The composite soil sample data reported herein show only TPHD was detected between 3 and 72 micrograms per kilogram (mg/kg), and the laboratory reported that these did not match the typical diesel fuel pattern. The soil samples collected from boreholes drilled for monitoring wells showed that contaminants were not detected. The groundwater TPHG detection was very low and also did not match the gasoline pattern. MTBE was detected in groundwater at MW-3 but was below the State Primary Maximum Contaminant Limit of 13 ug/l. These data do not indicate a significant soil or groundwater contaminant problem in our opinion. January 5, 2009 Page 7 of 12 MAIN OFFICE • 1707 Ln-1'LE ORCHARD STREET,SUITE A •SAN JOSE•CA•95125 MAILING ADDRESS•Y.U.Box 36303•SAN JOSE•CA•95158-6103•4081979-0661 ,408/979-0621 FAX•L.nsCUNST'!R;noL.COn7 E-MAIL GENEILAL AND FNGINEERING CONTRACTOR•HAZARDOUS SUBSTANCE REMOVAL CONTRACTOR•SITE ENVIRONMENTAL ASSESSMENT'S WETLAND ANO RIPARIAN HABITAT—AssEssMENT'—DESIGN—RESTORATION—CONSTRUCTION—MITIGATION MONITORING