ARCHIVED REPORTS_WELL INSTALLATION AND SOIL AND GROUNDWATER SAMPLING

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LIGHT, AIR & SPACE CONSTRUCTION ENVIRONMENTAL SERVICES COMPANY ' Slate Contractor's License Number 445403 State EPA R.E.A.Number 04072 Office 408-979-0661 ' All samples retained for chemical analysis were stored in a clean, covered cooler-box/ice chest on crushed ice at a temperature of about four degrees Celsius for transport to the Laboratory (see ' chain-of custody below). Soil samples extruded from the other rings were lithologically logged using the USCS. Sampler ' shoe cuttings togging, blow counts, drill rig response and bit penetration rate were logged as needed. The lithology log includes field descriptions of the soil lithologic variations, field estimated moisture conditions, geologic data, drill rig response and any unusual characteristics ' that may indicate the presence of chemical contamination (stain and odor) (see attached Exploratory Boring Logs and Well Construction Details). ' Soil samples were collected from the soil stockpile area on October 7, 2008. Following a field discussion about sample locations with the EHD representative, ten four-point soil samples were collected from the stockpile at depths of 12 and 24 inches below the surface. Hand coring ' equipment (auger sampler) were cleaned prior to sampling and between each sampling location. Each portion of the composite samples were collected in brass liners completely filled with soil. Each liner was then sealed with Teflon paper and plastic endcaps, labeled, logged onto a chain- of-custody form and placed in a chilled ice chest on crushed ice. ' 3.0 Monitoring Well Construction Wells were installed under approved EHD permits and a Well Inspector was present to witness ' the installation of the annular seal. Soil borings were drilled with a continuous-flight hollow- stem auger of nominal 8 inches outside diameter (about a 3-inch annular space for well construction). The borings were advanced to the uppermost water bearing. Each boring ' completed as groundwater monitoring well used 2-inch ID Schedule 40 PVC pipe with 0.020- inch machine-cut slots. Casing sections were threaded and screwed flush together; glues were not used. The well slots may extend about 1 to 2-feet above depth of first encountered ' groundwater. The annulus of the perforated section was packed with clean #3 Lonestar sand to a level about 2-feet above the slotted interval (previous field experience has shown this monitoring well design has worked well in stratified alluvial/fluvial environments similar to those on-site). Final well design was adjusted in the field to site-specific subsurface conditions observed in each borehole. A 1-2 foot thick bentonite seal was placed on top of the sand pack and allowed to ' hydrate to prevent grout invasion into the sand pack. A cement grout annular seal using Portland Type 1/11 (94 pound bag) cement to about five-gallons of water were mixed and placed by tremie line so that extends to the surface was placed by tremie line from the bottom to top of the ' remaining annular space above the bentonite. The wellhead casing was locked to prevent ' January 5 2009 Page 3 of 12 MAIN OFFICE • 1707 LITTLE ORCHARD STREET, SUITE A• SAN JOSE•CA•95125 MVLNG ADDRESS•P.O.Box 36303•SAN JOSE•CA•95158-6303 •40M79-0661 •408/979-0621 FAX•]AY-u;S i vI A� 1_1 I a E MA6. ORNF.R.AL.AND ENGINEERING CONTRACTOR•HAZARDOUS SCBST.-INCE RENIOV,,I.C11IRACTOR 0 SITE ENVIRONMENTAL ASSEI MENTS WETLAND AND RIPARIAN HABITAT—ASSESSMENT—DESIGN—RESTORATION—CONSTRUCTION—MITIGATION MONITORING