The study was commissioned to establish the scientific rationale for existing wastewater discharge legislation for Alberta East Slopes coal mines. Three water quality parameters - total suspended solids, pH and total iron - and four design flow parameters - applicability of the dam and canal safety guidelines, the two effluent water quality exemptions for 10 year 24- hr. precipitation events, and the \"no-discharge\" requirement for surface runoff from facilities and for tailings ponds were considered. Data sources for the review included: world scientific literature, relevant federal (Canada and U.S.A.), provincial, territorial and state legislation, available background water quality data, and personal communications from coal company and regulatory personnel.