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1.0 INTRODUCTION The results of a groundwater extraction pilot test conducted during the second half of 2009 are presented in this report. The test was first suggested by Upgradient Environmental Consultants in-December 2006,but was put in abeyance while Valley Motors performed the work necessary to comply with a directive from the San Joaquin County Environmental Health Department to perform an air sparging pilot test. After the sparging test was performed in August 2007, Upgradient Environmental concluded that air sparging would be ineffective at this site, and SJCEHD concurred. The test report again recommended conducting an extraction test to evaluate the practicality of groundwater extraction to remediate the site. In January 2008, Valley Motors and Upgradient Environmental complied with a request from San Joaquin County Environmental Health Department to prepare a Feasibility Study evaluating two potential groundwater remediation methodologies.The Feasibility Study compared the anticipated costs and effectiveness of in-well air stripping and groundwater extraction and treatment, and concluded that extraction was more likely to be cost-effective. SJCEHD then authorized Valley Motors to prepare a work plan for a pilot test of groundwater extraction. The initial work plan was submitted in March 2008 and approved by SJCEHD in April 2008. However, due primarily to financial reasons; Valley Motors was unable to proceed with implementation of that plan. After further correspondence in late 2008 and a meeting with the regulatory agency in early 2009, a revised work-plan was prepared.that had a more limited and less aggressive scope. The revised plan, summarized briefly below, was approved by SJCEHD in April 2009. 1.1 Summary of Work Plan The revised work plan proposed utilizing the most highly impacted monitoring well as the test well and pumping an unspecified volume of groundwater to a temporary above- ground storage tank over a period of several weeks. Although monitoring well VM-2 is only 2 inches in diameter,previous monitoring has demonstrated that the well can sustain a pumping rate of at least 1 gallon per minute (gpm)without going dry, and therefore this well would be suitable for a limited test. A water sample collected from the well, either at the time of hookup or just prior during regularly scheduled groundwater monitoring, would provide a baseline hydrocarbon concentration that could be compared to any changes in concentration that might take place during the test. 1 II