In the context of contaminated sites, risk assessments have a dual purpose: to determine the level of contamination and to assess the effectiveness of remediation measures. The risk assessments apply complex models for the dispersal of pollutants based on dose-response curves producing probabilities and expected val-ues. In this paper we point to the need for extending the assessments to place stronger emphasis on uncertainties than commonly seen in the risk assessments conducted today. A recently developed risk frame-work designed to better reflect such uncertainties is presented and applied to a case study, a site whose con-tamination is due to past and existing activities in relation to a chemical plant.