Laserfiche WebLink
ATTACHMENT A <br /> SUMMARY OF PREVIOUS INVESTIGATIONS <br />'EI <br /> Chevron 9-8632, 575 Grant Line Road, Tracy, CA <br /> There are currently four groundwater-monitoring wells located at the site. During the <br /> third quarter 2001 , total petroleum hydrocarbons quantified as diesel (TPHd) were not <br /> detected in any of the groundwater samples from the four wells. Total petroleum <br /> hydrocarbons quantified as gasoline (TPHg) were detected in two of four samples at <br /> concentrations of 280 µg/l (MW-3) and 460 µg/1 (MW-4). Benzene was detected in two <br /> of four samples at concentrations of 4.6 µg/1 (MW-3) and 75 µg/1 (MW-4) . Methyl- <br /> tertiary-butyl-ether (MtBE) was detected in all four samples (only the sample from <br /> MW-2 was confirmed by EPA Method 8260) at concentrations ranging from 8 . 1 µg/1 <br /> (MW-4) to 160 µg/1 (MW-2) . Groundwater flow has been reported consistently to the <br /> northwest at gradients ranging from 0. 007 to 0.02 Will <br />