Laserfiche WebLink
Human Health Risk Assessment <br /> Former Mobil Oil Bulk Plant 04-343 <br /> 500 East Grant Line Road <br /> Tracy, California _ <br /> 6.4.1.2 Hazard Indices Resulting from Toluene, Ethylbenzene ind Xylenes in Nearby <br />' Commercial Building <br /> ' The Hazard Indices resulting from potential exposure to toluene, ethylbenzene, and xylenes <br /> through volatilization and transport from subsurface soil are 5 2.0 x 10', <- 2.5 x 10-3, and <br /> 3.0 x 10-3, respectively, for the potential offsite exposure scenario The composite Hazard <br /> Index for potential exposure to the three noncarcinogenic chemicals is 5 5.7 x 10-3. The <br /> ' composite Hazard Index is the sum of the Hazard Indices for each of the chemicals. This value <br /> is approximately 175 times less than an acceptable Hazard Index of 1.0. <br /> 6.4.2 Hazard Indices from Inhalation of Toluene, Ethylbenzene, and Xylenes Under <br /> Future Site Conditions <br /> 7 <br /> 6.4.2.1 Ambient Concentrations of t owene, trnywenzene, and Xylenes in Onsite <br /> ' Commercial Building <br /> The calculated airborne concentrations of toluene, ethylbenzene, and xylenes in an onsite <br /> commercial building are approximately 5 1.1 x 101 mg/ml, 5 7.0 x 10' mg/m3, and <br /> 5 2.6 x 101 mg/m3, respectively. <br /> i <br /> 6.4.2.2 Hazard Indices in Onsite Commercial Building <br /> ' The Hazard Indices resulting from potential exposure to toluene, ethylbenzene, and xylenes <br /> through volatilization and transport from subsurface soil into an onsite commercial building are <br /> ' 5 5.5 x 10-5, 5 7.0 x 10', and S 8.7 x 10', respectively. The composite Hazard Index for <br />` potential exposure to the three noncarcinogenic chemicals is 5 1.6 x 10-3. The composite <br /> ' Hazard Index is the sum of the Hazard Indices for each of the chemicals. This value is <br /> approximately 600 times less than an acceptable Hazard Index of 1.0. <br /> 30-0136-11 <br /> .._ 6-5 <br />