Laserfiche WebLink
Human Health Risk Assessment <br /> Former Mobil Oil Bulk Plant 04343 <br /> 500 East Grant Line Road <br /> Tracy, California <br /> 6.3.1 Carcinogenic Risk from Inhalation of Benzene Under t;urrent Site Conditions <br /> ' 6.3.1.1 Airborne Concentration of Benzene in Nearby Commer-�al Building <br /> The calculated airborne benzene concentration in a nearby commercial building is <br /> approximately 9.6 x 10' mg/m3. This value is approximately 300 times less than the 1990-1991 <br /> threshold limit value - time weighted average (TLV-TWA) acceptable guideline of 0.3 mg/m3 <br /> ' suggested by the ACGIH (1990). <br /> ' 6.3.1.2 Incremental Cancer Risk Resulting from Benzene in Nearby Commercial Building <br /> The incremental cancer risk resulting from potential exposure to benzene through volatilization <br /> tand transport from subsurface soil into a nearby commercial facility is 7.0 x 10-' as delimited <br /> by the Reasonable Maximum Exposure scenario. <br /> ' 6.3.2 Carcinogenic Risk from Inhalation of Benzene Under Future <br /> Site Conditions <br /> i <br />' 6.3.2.1 Airborne Concentration of Benzene in Onsite Commercial Building <br /> The calculated airborne benzene concentration in a hypothetical onsite commercial building is <br /> approximately 3.0 x 10' mg/m3. This value is approximately 1000 tirnes less than the 1990- <br /> 1991 TLV-TWA acceptable guideline of 0.3 mg/m3 suggested by the ACGIH (1990). <br />' 6.3.2.2 Incremental Cancer Risk in Onsite Commercial Building <br /> The incremental cancer risk resulting from potential exposure to benzene through volatilization <br /> from subsurface soil and transport through the concrete foundation into a hypothetical onsite <br /> commercial building is :5 2.0 x 10-' as delimited by the Reasonable Maximum Exposure <br />' scenario. <br /> 30-0136-11 <br /> 6-3 <br />