PARENT SESSION
PW11 - Site-Specific Risk Assessments
Wednesday, 20 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P843) Site-Specific Ecological Risk Assessment: The TRIAD approach in practice.
Mesman, Miranda*,1, Rutgers, Michiel1, Peijnenburg, Willie1, Bogte, Jaap1, Dirven - Van Breemen, E.1, De Zwart, Dick1, Posthuma, Leo1, Schouten, A.1, 1 National Institute for Public Health and the Environment (RIVM), Bilthoven, Utrecht, The Netherlands
ABSTRACT- Assessment of ecological risks of soil contamination at a site can be used for determining the urgency and goals of remediation, and for spatial planning of land-use. A formal decision support system (DSS) was proposed to configure instrumentation (sets of prescribed calculations, chemical measurements, bioassays, and field observations). The DSS consists of three elementary steps: 1. definition of actual or desired land-use, such as nature reserve, recreation, or agriculture; 2. summing up site-specific ecological features related to this land-use, like key species and life support functions; 3. instrumentation according to a TRIAD approach, based on the analysis of different site-specific sources of information (environmental chemistry, toxicity, ecology) and final integration. Three tiers of precision can be applied; qualitative, semi-quantitative, and fully quantitative in order to make up a cost-effective system. A presentation format was developed to communicate risk assessment results without loosing track of underlying parameters. Furthermore, conceptual uncertainties in individual assessment parameters were adequately quantified by a factor describing the differences between TRIAD data. Some representative results of the TRIAD approach for several field trials will be shown in this presentation. In each case study, it will be shown that application of the DSS and the TRIAD provides integrated and solid data useful for risk assessment procedures.
Key words: Site-specific ecological risk assessment, TRIAD