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Stantec <br /> May 6, 2009 <br /> Page 3 of 5 <br /> SOIL AND GROUNDWATER INVESTIGATION ACTIVITIES <br /> Permitting/Site-Specific Health and Safety Plan/Utility Clearance <br /> Soil boring permits were obtained from the SJCEHD prior to advancing four soil borings, GP-1 <br /> through GP-4 (Attachment A). <br /> Stantec prepared a site-specific Health and Safety Plan for soil boring advancement and <br /> sampling activities at the site, as required by the Occupational Health and Safety Administration <br /> (OSHA) Standard "Hazardous Waste Operations and Emergency Response" guidelines (29 <br /> CFR 1910.120). The document was reviewed and signed by Stantec personnel and <br /> subcontractors performing work at the site. <br /> Prior to conducting subsurface work at the site, USA was contacted to delineate subsurface <br /> utilities near the site with surface markings. In addition, a private utility locator service was <br /> contracted to clear each of the drilling locations. <br /> Soil Borings <br /> On February 4, 2009, Stantec supervised as Gregg Drilling and Testing, Inc. (Gregg) of <br /> Martinez, California advanced four direct push soil borings (GP-1 through GP-4) at the locations <br /> shown on Figure 2. The first five feet of each boring was advanced via hand auger. Below 5 <br /> feet below grade surface (bgs), each boring was advanced using a truck-mounted rig equipped <br /> with a 2-inch diameter Macro Core® sampling device to a total depth of 20 feet bgs. The soil <br /> borings were abandoned after sampling from total depth with neat cement grout and capped <br /> with concrete to match the existing grade. Copies of the field notes are included in Attachment <br /> B. <br /> Soil Sampling <br /> Soil samples were collected at selected intervals in the boreholes from the continuous core <br /> sampling tubes. Down hole drilling equipment was cleaned before advancing each borehole, <br /> and sampling equipment was cleaned between each sampling interval. Each soil sample was <br /> screened for hydrocarbon vapors using a portable photoionization detector (PID). Soils <br /> encountered during drilling were logged by a Stantec field geologist, working under the <br /> supervision of a California registered geologist. <br /> Soil samples were collected using 2-inch by four-foot long core barrel containing a 1.75-inch <br /> diameter clear acrylic sampling tube. Selected soil samples retained for analysis were labeled <br /> and capped with Teflon® sheets and plastic end caps. The samples were then placed on ice in <br /> an insulated container, and transported to Kiff Analytical laboratory (Kiff) located in Davis, <br /> California, accompanied by the appropriate Chain-of-Custody (COC) documentation. Soil <br /> samples were analyzed for TPHg, BTEX, methyl tertiary butyl ether (MtBE), diisopropyl ether <br /> (DIPE), ethyl-tert-butyl ether (EtBE), tert-amyl-methyl ether (TAME), tertiary butanol (TBA), 1,2- <br /> dichloroethane (1,2-DCA), and 1,2-Dibromoethane (EDB) by EPA Method 82608. The soil <br /> sample collected from GP-1 was also analyzed for total petroleum hydrocarbons as motor oil <br /> (TPHmo) using EPA Method 8015M. Copies of the field notes are included in Attachment B. <br /> Soil Stratigraphy <br /> Based on the description of soil samples collected from soil borings GP-1 through GP-4, the soil <br /> stratigraphy encountered consists mainly of waterbedded clays, silts and sands from ground <br /> 14113 Soil and Groundwater Assessment Results.doc <br />