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28 June 2001 <br /> AGE-NC Project No. 95-0103 <br /> Page 3 of 9 <br /> 3.2. DRILLING, SOIL SAMPLING AND WELL COMPLETION <br /> AGE proposes to install three six-inch diameter ground water extraction wells. The proposed ground <br /> water extraction wells will be placed at the southwest corner of the site and on the western edge of <br /> the site, in the area of highest known ground water contamination. Based on distribution of <br /> hydrocarbon-impacted ground water detected in sample from the monitoring wells on the site, AGE <br /> proposes three six-inch diameter ground water extraction wells to be located approximately 40 feet <br /> apart along the western edge of the site (See Figure 2). The extraction wells will be screened from <br /> 10 to 30 feet bsg to address the more highly permeable zone from 20 to 30 feet bsg containing the <br /> most intensely impacted ground water. <br /> Following installation,the extraction wells will be developed to maximize water flow into the wells <br /> and minimize the amount of fine-grained sediment drawn into the wells during pumping or bailing. <br /> Procedures for well installation and development are presented in Sections 4.1. to 4.3., respectively. <br /> The soil borings on the site to be completed as the ground water extraction wells will be advanced <br /> with 15-inch hollow-stem augers. All augers will be cleaned prior to advancement in each boring <br /> location. <br /> 3.3. GROUND WATER SAMPLING AND ANALYSIS <br /> Following the installation of the ground water extraction system; ground water monitoring and <br /> sampling activities will be conducted for all the monitoring wells on a quarterly basis for a minimum <br /> of one year (four sampling events) or until directed to cease monitoring and sampling by the <br /> PHS-EHD. Monitoring activities will include recording depth to ground water measurements, <br /> properly purging monitoring wells to be sampled and collection and analysis of ground water <br /> samples. Ground water sample collection protocols have been previously described in Quarterly <br /> Report-Second Quarter 2001, dated 08 June 2001 and prepared by AGE. <br /> Ground water samples will be analyzed by a State of California Department of Health Services <br /> (DHS)-certified laboratory for the analytes noted in Section 3.8. <br /> Laboratory reports for ground water analyses, testing methods, laboratory quality assurance/quality <br /> control(QA/QC)reports and sample chain of custody documentation will be presented in quarterly <br /> reports with findings and recommendations. <br /> 3.4. WELL PUMPS, INSTALLATION AND PROCESS PIPING <br /> It is anticipated that a Grundfos Rediflow down-well pumps,type 5E5,equipped with Franklin''/Z hp, <br /> 208 volt, 3-wire motor will be installed in the newly installed ground water extraction wells and the <br /> existing four-inch diameter wells. In the two-inch diameter ground water wells, Grundfos Rediflow <br />