Laserfiche WebLink
3.3 Petroleum Mass In Groundwater <br /> PSC evaluated current residual petroleum mass in groundwater based on <br /> current isoconc.entration contours Illustrated in Figure 4 PSC's evaluation <br /> utilizes an aquifer porosity of 35 percent and a groundwater thickness of 50 <br /> feet, which is a conservative assumption that the entire water bearing zone is <br /> Impacted As shown in Table 7, PSC estimates that there are approximately <br /> 14 23 kilograms of TPH-G compounds remaining in site groundwater This J <br /> current mass is significantly lower than the previous mass of 76 17 kilograms <br /> that was estimated utilizing May 1999 data, reflecting the effectiveness of <br /> natural degradation and PSC's engineered remedial efforts at the site <br /> 3.4 Oxygenates Analytical Results <br /> Current DIPE concentrations display general decreases since the installation <br /> of new sparging well SP-A DIPS was detected in samples collected from / <br /> wells MW-12 and SP-1 at concentrations of 4 3 µg/l and 29 pg/l, respectively <br /> (see Figure 6) <br /> MTBE was detected in the current groundwater sample collected from well <br /> MW-10 at a concentration of 24 µg/1 PSC considers the detection of MTBE <br /> in this sample as potentially anomalous MTBE has never been detected in <br /> groundwater samples collected at this site Furthermore, BTEX and TPH-G <br /> compounds have been non detect at this location for at least the past three <br /> monitoring events PSC will continue to monitor MTBE at this location for <br /> confirmation <br /> TBA was detected in current groundwater samples collected from wells <br /> MW-10 and MW-13 at concentrations of 480 pg/1 and 27 µg/l, respectively <br /> Again, PSC considers the detection of TBA in these samples as potentially <br /> anomalous TBA has only been detected sporadically from site monitoring <br /> wells samples and never before in samples collected from these two wells <br /> PSC will continue to monitor TBA at these locations for confirmation <br /> 10 <br /> November 2002 Cr0U11dl%a1Lr Monitoring And Remediation Status Report <br /> I he h-irtharatns I3al.tng Compviy <br /> 2651 South Airport Way Stockton C.atifomia <br /> Prep irLd for 1 IIF i XRIFI( RUN',1RAI,INC CONPkm Prepamd by Philip SUVICCS Corp <br /> li V NV\G2100S 12512 i set G\S,t lion+51o6a..1u I621non doc Dl.(AmbLr 9 2002 <br />