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26 September 2005 <br /> AGE-NC Project No. 05-1329 <br /> Page 5 of 7 <br /> concentrations of MTBE and Benzene detected in the ground water samples collected exceed the <br /> DHS's Maximum Contaminant Levels (MCL) or Action Levels for drinking water. <br /> CAM 17 metal barium was detected in the ground water samples collected from boring B 1 through <br /> B3 at maximum concentrations of 0.29 µg/l (B1),0.16 µg/1 (B3)and 0.05 µg/l(132). However,the <br /> concentrations fell within the range of background concentrations for these metals in California <br /> ground water and well below the total threshold limit concentrations (TTLC) for hazardous waste <br /> established by the State of California. <br /> No other target analytes were detected at or above laboratory reporting limits in the soil and ground <br /> water samples analyzed. The analytical results are summarized in Tables 1 through 4. Copies of the <br /> laboratory report (CTEL Project No. CT214-0509072), quality assurance and quality control <br /> (QA/QC) report and chain of custody forms are included in Appendix B. <br /> CONCLUSIONS <br /> The presence of CAM 17 metals on the site does not seem to be a concern, as the concentrations <br /> detected are all well below the TTLC for hazardous waste established by the State of California. <br /> The presence of various hydrocarbon compounds in the soil and ground water are a concern. The <br /> concentrations of hydrocarbons in the soil samples analyzed are low to non-detect while the <br /> concentrations of hydrocarbons are significantly high to low in the ground water samples analyzed. <br /> The highest concentrations of hydrocarbon contamination in the soil and ground water samples <br /> analyzed are from boring B 1 which is approximately 40 feet east of the former underground storage <br /> tanks (UST) at the adjacent property. <br /> The soil samples analyzed were collected from the top of the water table or smear zone, while <br /> samples collected above this level in all three boring locations did not indicate the presence of <br /> contaminates by either odor or PID readings with exception to the 15 foot sample at the B 1 location <br /> closest to the former off-site USTs.This most likely can be attributed to a source area some distance <br /> away from the soil boring locations. <br /> The ground water concentrations are still high in boring B3 (approximately 100 feet east of the <br /> former USTs)while the soil concentrations detected at are very low.and can probably be attributed <br /> to absorption from the ground water contamination at this location. The only constituent detected <br /> in boring B2 was MTBE in the ground water sample at a concentration slightly above the DHS's <br /> action level for drinking water. Based on the off-site data and the borings completed on the site by <br /> the investigation west (392 Moffat Boulevard) the Agricultural Commissions, including on-site <br /> Advanced GeoEnvironmental,Inc <br />