FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

i Additional Site Assessment Report STALLWORTH AUTO SALES 602 North California Street, Stockton, California 1 .0. INTRODUCTION At the request of Mr. Gary Stallworth of Stallworth Auto Sales, Advanced GeoEnvironmental, Inc. (AGE) has prepared this Additional Site Assessment Report for the property located at 602 North California Street, Stockton, California (site). The scope of work included the advancement of three cone penetration test sounding borings (one off-site), advancement of ten borings for the collection of grab ground water samples (four off-site), installation of three ground water monitoring wells (one off-site), submission of analytical data to the State Water Resources Control Board's GeoTracker information management system, and preparation of this report. The location of the site and surrounding area are illustrated on Figure 1 ; structures, former underground storage tank (UST) locations, and soil boring and monitoring well locations are illustrated on Figure 2 . Additional site background information is provided in Appendix A. The objective of the subsurface investigation was to delineate the vertical and lateral extent of ground water contamination. Field work was conducted in accordance with guidelines issued by the Central Valley Regional Water Quality Control Board (CVRWQCB) for the investigation of UST sites. Cone penetration test sounding, probe boring, and monitoring well installation procedures are outlined in the AGE-prepared Additional Site Assessment Work Plan dated 12 December 2007. 2.0. PROCEDURES On 05, 06 and 07 February 2008, cone penetration testing and grab ground water sampling was conducted on-site and off-site (521 East Oak Street) utilizing a 25-ton truck-mounted cone penetration testing (CPT) drill rig. Based upon the analytical results of grab ground water samples collected during the CPT investigation, on 13 and 14 March 2008, two ground water monitoring wells, MW-9 and MW41 , were installed on-site and one ground water monitoring well, MW- 10, was installed off-site at 521 East Oak Street utilizing a CME-75 drill rig with 8-inch hollow stem augers. The monitoring wells were developed on 20 and 21 March 2008 and surveyed on 02 April 2008 . 2 . 1 . CPT INVESTIGATION On-site, lithologic data were collected from CPT sounding borings CPT-6 and CPT-7; grab ground water samples were collected from two borings immediately adjacent to each CPT sounding boring to access the vertical and lateral extent of hydrocarbon-impacted ground water. In addition, paired borings B-6 were advanced on-site for the collection of two grab ground water samples. Advanced GeoEnvironmental, Inc.