Millennium developed a unique approach to estimating the impact of dust emissions from a proposed 5 Mt/year coal mine near Edson Alberta. Traditional modelling of mine emissions tends to over-estimate concentrations of dust for a number of reasons, including capture of dust by intervening vegetation. MEMS applied the results of monitoring research programs to its CALMET/CALPUFF model output to more closely align predictions with monitoring observations. The benefits to MEMS’ client of the more realistic assessment results included reduced monitoring requirements and implementable mitigation approaches.