Title: | Development of a modular vapor intrusion model with variably saturated and non-isothermal vadose zone |
Author(s): | Bekele DN; Naidu R; Chadalavada S; |
Address: | "Global Centre for Environmental Remediation, ATC Building, University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia. Dawit.Bekele@newcastle.edu.au. CRC for Contamination Assessment and Remediation of the Environment, ATC Building, University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia. Dawit.Bekele@newcastle.edu.au. Global Centre for Environmental Remediation, ATC Building, University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia. CRC for Contamination Assessment and Remediation of the Environment, ATC Building, University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia" |
DOI: | 10.1007/s10653-017-0032-5 |
ISSN/ISBN: | 1573-2983 (Electronic) 0269-4042 (Linking) |
Abstract: | "Human health risk assessment at hydrocarbon-contaminated sites requires a critical evaluation of the exposure pathways of volatile organic compounds including assessments of vapor exposure in indoor air. Although there are a number of vapor intrusion models (VIM) currently available, they rarely reproduce actual properties of soils in the vadose zone. At best, users of such models assume averaged parameters for the vadose zone based on information generated elsewhere. The objective of this study was to develop a one-dimensional steady-state VIM, indoorCARE model, that considers vertical spatial variations of the degree of saturation (or effective air-filled porosity) and temperature of the vadose zone. The indoorCARE model was developed using a quasi-analytical equation that (1) solves the coupled equations governing soil-water movement driven by pressure head and a soil heat transport module describing conduction of heat and (2) provides a VIM that accommodates various types of conceptual site model (CSM) scenarios. The indoorCARE model is applicable to both chlorinated hydrocarbon and petroleum hydrocarbon (PHC) contaminated sites. The model incorporates biodegradations of PHCs at a range of CSM scenarios. The results demonstrate that predictions of indoor vapor concentrations made with the indoorCARE model are close to those of the J&E and BioVapor models under homogeneous vadose zone conditions. The newly developed model under heterogeneous vadose zone conditions demonstrated improved predictions of indoor vapor concentrations. The research study presented a more accurate and more realistic way to evaluate potential human health risks associated with the soil-vapor-to-indoor-air pathways" |
Keywords: | "Air Pollutants/*analysis Air Pollution, Indoor/*analysis Hot Temperature Humans Hydrocarbons/analysis *Models, Theoretical Population Health Pressure Risk Assessment Soil Pollutants/*analysis Volatile Organic Compounds/*chemistry Site screening Spatial va;" |
Notes: | "MedlineBekele, Dawit N Naidu, Ravi Chadalavada, Sreenivasulu eng Netherlands 2017/10/13 Environ Geochem Health. 2018 Apr; 40(2):887-902. doi: 10.1007/s10653-017-0032-5. Epub 2017 Oct 12" |