PT01 Assessing Contaminated Soil Sites
Exhibit Hall
8:00 AM - Tuesday, 11 November 2003
(PT007) Testing framework for assessing contaminated soils for a site-specific risk assessment.
Stephenson, G1, Gilbertson, M1, Feisthauer, N1, 1 ESG International Inc., Guelph, ON, Canada
ABSTRACT- Toxicity tests in support of either Tier 2 or Tier 3 site-specific ecological risk assessment can be valuable to regulators and site managers. They reduce the uncertainty associated with the use of toxicity values reported in the literature and they produce data that reflect and integrate site conditions and characteristics. To this end, a framework for testing has been proposed in order to address the soil contact exposure pathway which is one of the most important exposure pathways for ecological receptors exposed to contaminated site soils. The framework consists of a phased approach to testing. The first phase involves the use of acute screening and chronic tests with plants, soil invertebrates and microorganisms exposed to undiluted site soil samples. The second phase of the testing framework also uses acute and chronic tests with these groups of test organisms but they invoke the use of soil dilution procedures to either identify threshold concentrations of effect or to identify remedial targets. Different approaches to site soil assessment are used for different situations. The framework will be presented and these approaches discussed as they relate to the assessment framework.
Key words: site soil assessment, terrestrial toxicity tests, ecological risk assessment, testing framework