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samples. Smaller diameter push rod(s) (typically 2 inches in outer diameter, but large enough to <br />almost completely fill the annulus of the outer push rod(s)) are advanced within the annulus of <br />the outer push rod to the total depth. The lead inner rod serves as a soil sampler, and an <br />acetate liner is inserted into the annulus of the lead inner rod prior to advancement. Once the <br />soil sample is collected, the inner rod(s) and sampler are retracted and the sample tubes are <br />removed from the sampler head. The sampler head is cleaned, filled with clean sample tubes, <br />and the process of advancing the outer rods prior to the advancement of the sampler rods <br />repeated until the total depth of sampling is reached. <br />The undisturbed soil samples intended for laboratory analysis are cut away from the acetate <br />sample liner using a hacksaw, or equivalent tool, in sections approximately 6 inches in length. <br />The 6 inch samples are lined at each end with Teflon® sheets and capped with plastic caps. <br />Labels documenting job number, borehole identification, collection date, and depth are affixed <br />to each sample. The samples are then placed into an ice-filled cooler for delivery under chain- <br />of-custody to a laboratory certified by the State of California to perform the specified tests. <br />Groundwater Sample Acquisition, Handling, and Analysis <br />Groundwater samples are collected from the borehole using a clean disposable plastic bailer. <br />The groundwater sample is discharged from the bailer through a low-flow control spigot directly <br />into laboratory provided, pre-cleaned, and chemically preserved (where appropriate) sample <br />containers for the analyses requested. Preservatives are used in the samples if appropriate for <br />the analyses, i.e. hydrochloric acid (HCI) for TPPH, BTEX, and fuel oxygenates by EPA Method <br />8260. <br />Labels documenting sample number, well identification, collection date and time, type of <br />sample and type of preservative (if applicable) are affixed to each sample. The samples are <br />then placed into an ice-filled cooler for delivery under chain of custody to a certified laboratory. <br />The type of preservative used is documented on the chain of custody form. <br />To help assure the quality of the collected samples and to evaluate the potential for cross <br />contamination during transport to the laboratory, a distilled-water trip blank accompanies the <br />samples in the cooler. The trip blank is analyzed for the presence of volatile organic compounds <br />of concern. For petroleum hydrocarbons, the trip blank is typically analyzed for TPHg, BTEX, and <br />fuel oxygenates by EPA Method 8260. <br />Borehole Completion <br />Upon completion of drilling and sampling, neat cement grout, mixed at a ratio of 6 gallons of <br />potable water per 94 pounds of Portland cement, is introduced, via a tremie pipe. Displaced <br />groundwater is collected at the surface into DOT approved 55-gallon steel drums, or an <br />equivalent storage container. For Direct Push boreholes, the outer drill rods are extracted as the <br />neat cement grout is introduced into the borehole, to prevent separate groundwater bearing <br />zones from communication. In areas where the borehole penetrates asphalt or concrete, the <br />Stantec