ARCHIVED REPORTS XR0000025 - Laserfiche WebLink

Home Browse Search

Bmeq] KLEINFELDER 4 2 MODEL PREDICTIONS ' Using a Cs benzene concentration of 1 7 milligrams-per-Liter (mg/L) (measured in the SP-1 groundwater sample), the model predicts that the associated Cx concentrations ' decrease rapidly at a conservative distance of 30 feet from the source to be within the associated MCL of 0 001 mg/L This calculated rapid reduction is primarily influenced ' by the relatively low hydraulic conductivity of the subsurface that has been measured at this facility This model indicates that the concentration of benzene may exceed its associated MCL beyond its southern property boundary based on the current <-- concentration results for well_MW=1I 1`- However,-it does not appear to pose a risk to ' potential receptors through the groundwater-ingestion exposure route Historically, benzene has been non-detect at this location The first positive reported value for ' benzene was in the previous June 2004 event at 0 0021 mg/L Using a Cs TPH-G concentration of 20 mg/L (measured in the SP-1 groundwater ' sample), the model predicts that the associated Cx concentrations decrease rapidly at a conservative distance of 24 feet from the source to be within the goal of 50 mg/L This calculated rapid reduction is primarily influenced by the relatively low hydraulic conductivity of the subsurface that has been measured at this facility This model indicates that the concentration of TPH-G may exceed its associated goal beyond its southern property boundary based on the current concentration results for well MW-11 However, it does not appear to pose a risk to potential receptors through the groundwater ingestion exposure route Historically, TPH-G has been non-detect at this location The first positive reported value for TPH-G was in the previous June 2004 ' event at 0 180 mg/L 7 C23-484517-B001SAC5R540 Page 11 of 14 August 11, 2005 Copyright 2005 Kleinfelder, Inc