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LIGHT, AIR & SPACE CONSTRUCTION ENVIRONMENTAL SERVICES COMPANY Statc Contmetor's License Number 445403 State EPA R.E.A.Number 04072 Office 408-979-0661 4.0 Soil Excavation from UST Pits and Soil Aeration On May 16, 2006, LA&S excavated soil from the former UST locations at the subject site. A representative from the SJC/EHD was present to observe the excavations and the extremity soil sampling. On the east side of the barn at the former location of the gasoline UST, an excavation approximately 14 feet by 24 feet by 12 feet in depth was dug and the excavation spoils were stock-piled in a designated location on the subject site for future bio-remediation. Eight (8) extremity soil samples were obtained from the sidewalls and bottom of this excavation (0616-6 (north side wall, 1 foot above bottom), 0616-7 (center bottom),0616-8 (west sidewall, 18 depth), 0616-9 (south end bottom, 1 foot above bottom), 0616-10 (southwest corner sidewall, 12 foot depth), 0616-11 (northeast comer sidewall, 12 foot depth), 0616-12 (southeast corner sidewall, 12 foot depth) and 0616-13 (south sidewall, 12 foot depth). One (1) groundwater grab sample was obtained from this excavation(0616-WS-3) (see Tables 5 and 6 below). On the west side of the bam at the former location of the diesel UST an excavation approximately 14 feet by 24 feet by 12 feet in depth was dug and the excavation spoils were stock-piled in a designated location on the subject site for future bio-remediation. Five (5) extremity soil samples were obtained from the sidewalls and bottom of this excavation (0616-1 (east side wall), 0616-2 (west side wall, 0616-3 (north sidewall), 0616-4(center bottom),0616-5 (south sidewall). Two (2) groundwater grab samples were obtained from this excavation(0616- WS-1-north end) and (0616-WS-2-south end). The soil and groundwater analytical laboratory reports have been forwarded to SJC/EHD and the soil and groundwater analysis data are presented in Tables 5 and 6 below. After the soil samples were obtained, the excavations were backfilled in 12 inch thick lifts with clean soil obtained from the subject site. The backfill material was mechanically compacted with a sheepsfoot wheel mounted on the backhoe. The excavated soil material was placed in a pre-determined location to the southwest of the barn in an area with an earthen berm and lined with visqueen material allowed to aerate. Groundwater monitoring wells were installed in 2008 for the SJC/EHD requested groundwater assessment. 5.0 Existing Monitoring Wells Currently three groundwater monitoring wells (MW-1, MW-2 and MW-3) exist on-site one well each adjacent to each former UST pit and one well adjacent to the soil aeration pad. The property owner currently plans to properly destroy these wells under approved SJCIEHD permits upon receiving a NFAR approval letter for"site closure"from the oversight agency. Page 5 of 16 MAIN OFFICE - 1707 LITTLE ORCHARD STREET,SUITE A-SAN JOSE-CA-95125 MAILING ADDRESS•P.O.BOX 36303•SAN JOSE•CA•95158-6303•4081979-0661 -4081979-0621 FAX-LASCONSTfa..AOL.COM E-MAIL GENERAL AND ENGINEERING CONTRACTOR-HAZARDOUS SUBSTANCE REMOVAL CONTRACTOR-SITE ENVIRONMENTAL ASSESSMENTS WETLAND AND RIPARIAN HABITAT—ASSESSMENT—DESIGN—RESTORATION—CONSTRUCTION—MITIGATION MONITORING