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LIGHT, AIR & SPACE CONSTRUCTION ENVIRONMENTAL SERVICES COMPANY State Contractor's License Number 445403 State EPA R.E.A.Number 04072 Office 408-979-0661 On the basis of the water data from the pits, the EHD requested further assessment of the groundwater and the site by performed by installing groundwater monitoring wells. Three monitoring well locations were discussed and approved with a representative of EHD and this report presents the installation and sampling of those wells. Ten four-point composite soil samples were also collected in October 2008 from the stockpile aeration area for chemical analysis and are presented in this report- Soil samples were obtained from approximate depths of 6"-12" and 18"-24" at pre-selected grid locations and the samples were composited by depth for analysis by the lab. 2.0 Exploratory Boring Drilling and Sampling 2.1 Introduction Three exploratory borings were drilled using hollow-stem augers at the locations shown on Figure 2. The borings and wells were permitted through EHD and an underground utility alert (USA) was called and the site utilities located prior to doing fieldwork. The wells were placed as close as practical to the original UST pits. Soil samples were taken at 5-foot increments and at intervals of geologic interest or obvious or suspected contamination to the total borehole depth. Additional samples were collected at the discretion of the supervising geologist. All logging was performed using the Unified Soil Classification System (USCS), together with pertinent geologic observations as appropriate for the site subsurface geology description. 2.2 Decontamination All augers were thoroughly steam-cleaned prior to arriving at the site. The driller brought adequate clean auger to complete all of the wells without reusing auger sections. All soil sampling tools (split spoons, cores, etc.) were disassembled, steam-cleaned or cleaned in soapy (TSP) water, rinsed with clean tap water prior to taking each sample. The cleaned tools were then reassembled with clean brass sample liners for the next sample collection. The drill rig was decontaminated prior to leaving the site. Contaminated drill cuttings and the soil samples not retained for chemical analysis, together with well purge, cleanup and cement mixing water were placed in labeled, closed top 55-gallon drums pending chemical analysis. The Client is responsible for proper storage and disposal of contaminated materials. 2.3 Soil Sampling and Logging Split spoon soil samples in the brass liners in the sampling tool (depending on sample recovery) were retained for chemical or physical testing. The samples were labeled and sealed in the field in their original liners. Sample liners ends were sealed with aluminum foil or Teflon®, capped with clean cap plugs, and labeled and logged onto chain of custody forms. January 5, 2009 Page 2 of 12 MAIN OFFICE • 1707 Lrrl'LE ORCHARD STREET, SurrE A • SAN JOSE•CA•95125 MAILING ADDRESS•P.O.Box 36303•SAN JOSE•CA•95158-6303•4081979-0661 •408/979-0621 FAX•I..gtil.crr,Icu<aul I nta E-MAIL GENERAL AND ENG3NEER1NG CONtRACTOR•HAZARDOUS SUBSTANCE REMOVAL CONI'RACTOR•SITE ENVIRONMEN-1-AL ASSLSSMEN'I'S WETLAND AND RIPARIAN HABITAT—ASSESSMENT—DESIGN—RESTORATION—CONSTRUCTION—MITIGATION MONITORING