This report, entitled 'Guideline Triad 2011, site-specific ecological risk assessment in Step 3 the Remediation Criterion', gives a description on how to perform a site-specific risk assessment as part of Dutch regulations. This description is meant as a guideline for straightforward application of the Triad in ecological risk assessment of contaminated soils.
On the 1st of January 2006 a renewal process was started to update the Dutch Soil Protection Act. The risk assessment of contaminated sites is described in the Circular letter Soil Remediation (2006). The so-called 'Remediation criterion' is part of the Circular letter and describes the way in which the urgency of soil clean-up is determined. The Remediation criterion was updated in 2008 and 2009. The next update will be effected in 2011.
This renewed guideline will be part of step three in the Remediation criterion, in which site-specific measurements and calculations are important elements. These investigations will be a basis for the assessment whether there is an unacceptable ecological risk of soil pollution, by chemical, toxicological and ecological research, or whether more research is needed. The different methods to be used in a Triad provide a 'Weight of Evidence' to the risk evaluation. Moreover, the Triad can be applied in a stepwise (tiered) way, in order to exploit the research in a cost-effective manner.
