ARCHIVED REPORTS_XR0003684 - Laserfiche WebLink

Home Browse Search

MW-9, MW-10, MW-11, MW-12, MW-17, and MW-18 contained either • non-detectable hydrocarbon concentrations or concentrations below DHS MCLS or drinking water The only HVOC concentrations detected at the site were relatively low concentrations of PCE in the groundwater sample collected from monitoring well MW-1, and relatively low concentrations of 1,2-DCP in groundwater samples collected from several wells screened in water- bearing zones below 19-feet bgs None of these HVOC concentrations exceeded DHS MCLs for drinking water 2. 17 November 9000 Monitoring Well Resamplins In November 2000, ASE resampled the monitoring wells on the north shoulder of West Yosemite Avenue to confirm the presence of MTBE in the intermediate zone and to provide additional baseline data for the evaluation of the interim remediation system Groundwater samples collected from monitoring well MW-16, screened in the intermediate water-bearing zone 49 to 64-feet bgs, contained 29 ppb MTBE These results are slightly lower than results in the September sampling The highest hydrocarbon concentrations were once again detected in groundwater samples collected from monitoring well MW-13, which contained 14,000 ppb TPH-G, 1,500 ppb benzene, 77 ppb toluene, 1 ,300 ppb ethyl benzene, 390 ppb total xylenes, 2,400 ppb MTBE, 95 p p b TAME, and 770 ppb TBA 2. 18 December 2000 Groundwater Sampliag In December 2000, ASE conducted the quarterly groundwater sampling for the site Free-floating hydrocarbons were still present on the groundwater surface in monitoring well MW-5 Hydrocarbon concentrations detected in groundwater samples collected from monitoring wells MW-4, MW-14, MW-16 and MW-19 decreased significantly from the previous sampling The hydrocarbon concentrations detected in groundwater samples collected from monitoring well MW-6 show a decreasing trend but still remained elevated The benzene, ethyl benzene, and MTBE concentrations detected in groundwater samples collected from monitoring well MW-13 increased from the previous sampling Overall there was a decrease in MTBE concentrations throughout the site with the exception of monitoring well MW-13 Franks One Stop Report — March 2001