WORK PLANS - Laserfiche WebLink

Home Browse Search

low Iftv, ✓ Quarterly Report - Third Quarter 2006 GREWAL'S MARKET 4100 East Fremont Street, Stockton, California 1.0. INTRODUCTION Advanced GeoEnvironmental,Inc. (AGE)has prepared this quarterly report for 4100 East Fremont Street (site), Stockton, California. The site setting is illustrated on Figure 1. Site structures and monitoring well locations are depicted on Figure 2. The objective of the work was to monitor dissolved petroleum hydrocarbon concentrations in ground water and to characterize ground water flow direction and gradient on the site. This report has been prepared in accordance with guidelines issued by the California Regional Water Quality Control Board - Central Valley Region (CRWQCB-CVR) for investigation of underground storage tank ` ST sites. A summary of previous investigations at the site was included in (UST) ary p g Quarterly Report- First Quarter 2006, dated 17 July 2006,prepared by AGE; ground water monitoring data acquired to date is included in the tables of this report. 2.0. GROUND WATER MONITORING PROCEDURES On 05 September 2006,ground water monitoring and sampling were performed at the site on ground water monitoring wells MW-1 through MW-4. Monitoring well construction details are summarized in Table 1. Ground water monitoring procedures for the site were performed as outlined in Monitoring Well Installation Work Plan -September 1999, dated 01 September 1999, prepared by AGE and approved by the EHD by letter dated 23 September 1999. 2.1. WELL MONITORING AND EVACUATION On 05 September 2006,depths to ground water were measured in each well from the top of the well casing to the nearest 0.01-foot utilizing a Solinst water level meter; ground water elevation was calculated by subtracting the measured depth to ground water from the surveyed casing elevation (Table 2). Ground water elevations were plotted and contoured on a scaled site map (Figure 3). After water levels were measured,approximately 10%to 18 gallons of ground water(a minimum of three casing water-volumes per well)were evacuated(purged)from wells MW-1 through MW-4 by lowering and raising a%-inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through each monitoring well screen section. A Watera-Hydro-Lift II pump equipped with a mechanical arm was utilized to surge the polyethylene hose. Temperature,pH and conductivity were measured for stabilization at regular purge-volume intervals from each well using an Oakton water analyzer. Field data and logs are in Appendix A. Purged ground water was containerized in California Department of Transportation (DOT)-approved model 17H 55-gallon drums and stored at the site. Advanced GeoEnvironmental,Inc.