The Scientific Enquiry Committee was appointed by the Hon. D.J. Russell, Minister of the Environment, to investigate factors associated with the discharge of effluents from the Great Canadian Oil Sands (GCOS) tailings pond dyke to the Athabasca River. The terms of reference of the Enquiry were to evaluate the impact of the discharges on the Athabasca River, and to provide recommendations on any necessary action to be taken by Alberta Environment and Great Canadian Oi1 Sands Limited. The general nature of the terms of reference has permitted an independent and unrestricted enquiry.