ARCHIVED REPORTS_XR0011003 - Laserfiche WebLink

Home Browse Search

Analytical Results (Third Quarter Only) Groundwater samples were not collected during the second quarter(July 2001)event. Analytical results for the October 2001 sampling event are presented in Tables 4,5,and 6. Table 4 presents groundwater sample analysis for TPH-gasoline and benzene,toluene,ethyl benzene,and xylenes(BTEX).Table 5 presents analytical results for MTBE and other oxygenate compounds.Table 6 presents analytical results for 1,2-DCA and EDB. The results are summarized below,dependent upon the location of the well in relation to the plume: upgradient,cross-gradient,or within the plume. Upgradient Wells-MW-DIS-3,-4,-5,-6,-7S,-7D,-89,-8D,-10 Upgradient wells were not sampled during this event. Cross-gradient Wells-MW-DIS-9 Crossgradient wells were not sampled during this event. Wells Within the Plume-MW-DIS-1, MW-DIS-2, NP-1-70', NP-1-80', NP-1-90', SVE-South and SVE-North TPH as gasoline and BTEX compounds were detected in groundwater samples collected from monitoring wells MW-DIS-1,MW-DIS-2,NP-1-70',NP-1-80',NP-1-90',SVE-South and SVE-North.With the exception of MW-DIS-1,the concentrations detected in these wells are consistent with previous sampling events(see Table 4). The concentrations of TPH as gasoline and BTEX concentrations in MW-DIS-1 have decreased from the previous sampling event. Concentrations continue to decline in MW-DIS-2. Downgradient Wells-MW-DIS-11,-11 D,-12,43,44,and-14D. Downgradient wells were not sampled during this event. Oxygenates -- Methyl-tert Butyl Ether(MTBE),tert-Butanol(TBA),Di-isopropyl ether(DIPE),Ethyl tert- butyl ether(ETBE),and tert-Amyl Methyl ether(TAME)have been eliminated from the sampling program at this site,since there have been no confirmed detections of these compounds.TBA has been non-detect for four quarters in all wells except SVE-North.TBA will continue to be analyzed on a semi-annual basis in SVE-North until there are 4 consecutive quarters of non-detects.TBA was not detected in SVE-North during this event (See Table 5). Other Additives All monitoring wells within the plume were sampled and analyzed for 1,2-DCA and EDB during this sampling event. The concentrations detected in these wells are consistent with previous sampling events(see Table 6). Recommendations Extent of Plume Five monitoring wells(MW-DIS-11,-12,-13,-14,and-14D)were installed downgradient of the site in November 2001.An additional deep monitoring well,MW-DIS-11D is scheduled 2