Laserfiche WebLink
n r <br /> TPHG was detected in 4 of the 10 sampled monitoring wells at concentrations ranging from 530 <br /> µg/1 (MW-8) to 18,000 µg/1 (MW-4). Benzene was detected in 5 of the 10 sampled monitoring <br /> wells at concentrations of 1.0 µg/l (MW-7) and 1,200 µg/1 (S-1). MTBE was detected by method <br /> 8260 in 3 wells at concentrations of 830 µg11 (MW-8), 16,000 µg11 (S-1) and 5,500 �tg/1 (S-2). <br /> Analytical data are summarized in the table and illustrated on Figure 3. Certified Analytical <br /> Reports and chain of custody documentation are presented in Appendix B. <br /> 5 CONCLUSIONS <br /> Groundwater samples from 4 of the 10 sampled monitoring wells (MW-4, MW-8, S-1, and S-2) <br /> contained detectable concentrations of petroleum hydrocarbons. Groundwater flowed toward the <br /> south-southeast during the first quarter 1999. <br /> As presented in the Remedial Action Plan, and based on telephone conversations with Mr. <br /> Harlan Knoll of the San Joaquin County Public Health Department, Pinnacle will submit a <br /> workplan and drilling permit applications to install two additional groundwater monitoring wells <br /> and one air sparge well. The two groundwater monitoring wells will delineate the extent of <br /> • petroleum hydrocarbon impacts to the west-southwest of the site. The air sparge well will be <br /> used to remediate groundwater in the vicinity of the tank complex. <br /> The material and data in this report were prepared under the supervision and direction of the <br /> undersigned. <br /> Pinnacle Environmental Solutions Pinnac iro ent utions <br /> [lam <br /> Matt Turner /eni <br /> Jo son <br /> Project Manager r Pro' ct Supervisor <br /> OAK\S:\USA100651QTRLY10065Q 199.DOC1uh:1 2 <br />