The review of the Australian National Environment Protection (Assessment of Site Contamination) Measure (NEPM), and workshops in Australia over a number of years involving regulators, industry representatives, consultants and researchers, have motivated the need to review and recommend a model of vapour behaviour for use in the development of health-based screening levels (HSLs) in Australia. In particular, suggestions from a recent workshop held on the Gold Coast Queensland, Australia in February 2008 led to the development of this summary report.
Here, the processes underlying vapour behaviour are described and two models are compared for their utility in modelling petroleum vapours in soil profiles and as they move from the subsurface into built structures. In addition, the need for inclusion of biodegradation and finite lifetime sources in modelling approaches during the development of HSLs is considered.
Four primary recommendations are made concerning: