Estimating exposure from a chemical spilled into a river

There is always the possibility of an accidental discharge of a chemical into a flowing river system. When it happens, knowledge is needed of the concentrations that can be expected downstream of the discharge. By taking advantage of an actual derailment in British Columbia it was possible to validate a set of dispersion equations for making such predictions. The model has been programmed to operate on a small microprocessor which makes the results immediately accessible to the decision makers.