Health Risk Assessment for Area 514 RCRA Closure

Gallegos, G M ; Hall, L C

Lawrence Livermore National Laboratory

关键词: Lawrence Livermore National Laboratory;    Storage;    Chronic Exposure;    Waste Processing;    National Security;   

DOI  :  10.2172/887276
RP-ID  :  UCRL-TR-212654
RP-ID  :  W-7405-ENG-48
RP-ID  :  887276

美国|英语

来源: UNT Digital Library

【 摘 要 】

Lawrence Livermore National Laboratory (LLNL) is a USDOE research and development institution for science and technology applied to national security. The specific area that is the subject of this document, Area 514, was the location of active LLNL waste treatment facilities until November 2003, and the operations there were authorized under interim status. The site is being closed pursuant to the requirements of the Resource Conservation Recovery Act. The DTSC-approved ''Closure Plan for Area 514 Treatment and Storage Facility, LLNL 2004'', states clean closure concentrations for certain organic compounds, metals and metalloids. if all soil samples contained measured concentrations less than these levels, it was agreed that the site would meet the requirements for clean closure. However, if the samples had measured concentrations greater than the clean closure levels, a more detailed risk assessment could be prepared to evaluate the potential effects of the actual measured levels. Soil samples collected from 33 locations in Area 514 were analyzed for 37 constituents of potential concern, as identified by the Closure Plan. Many of these compounds and elements were not detected. However, 10 metals or metalloids were present at levels above the clean closure requirements, and 19 organic compounds were identified as contaminants of potential concern. Following the guidance in the Closure Plan, a health risk assessment is presented in this document to demonstrate the low level of potential health effects from the remaining constituents and to support clean closure of the site. Three types of hypothetical receptors were identified: an intrusive construction worker conducting trenching in the area, a bystander worker in a nearby building, and a future resident. Of the worker receptors, the intrusive construction worker was found to have the greater overall chronic exposure, with a theoretical calculated carcinogenic risk of 4 x 10{sup -8}, a chronic hazard index of 8 x 10{sup -3}, and an acute hazard index of 9 x 10{sup -1}. The estimated incremental cancer risk for the residential receptor, 1 x 10{sup -6}, was calculated by adjusting contaminant concentrations to account for background levels of metals at the Livermore LLNL site. When no adjustments for background concentrations are made, the estimated incremental cancer risk is 3 x 10{sup -6}. The chronic hazard index for the residential receptor, 2 x 10{sup -1}, was developed without accounting for background concentrations of metals. These values are all below levels associated with health concerns, and support the conclusion that further cleanup of the area is not necessary.