Selection of representative TPH fractions based on fate and transport considerations (Total Petroleum Hydrocarbon Criteria Working Group series)

The overlying theme to this series is the importance of exposure potential when defining human health risk. The fate and transport of a chemical or mixture defines the exposure route, and in conjunction with receptor properties, concentrations at receptors. If fate and transport is not considered, unrealistic human health risks could be calculated, resulting in misinformed decisions about site clean-up and regulatory guidance. We hope you find these documents useful in your efforts to evaluate and determine acceptable risk-based criteria at petroleum sites. This document summarizes the methods used in vol. 2 to delineate TPH into equivalent carbon number fractions based on fate and transport considerations. Once the fractions were defined, fraction-specific values of relevant physical-chemical properties were calculated based on correlation's to boiling point. The analytical method, fate and transport considerations and toxicity criteria (see vol. 4) are the technical elements which fit into a risk-based framework for determining human Heath Based Criteria at petroleum hydrocarbon contaminated sites.