We have carried out quantitative analyses of dissolved sodium, potassium, calcium, magnesium, chloride, carbonate, bicarbonate, ‘alkalinity’, sulphate, aluminum, iron, and silicon in tailings water from the GCOS tailings pond and from the Syncrude pilot plant. Surface tensions of these waters have been measured over a range of pH values, and effects of added Mg2+ and Ca2+ ions on surface tension have been investigated. Some similar measurements have been made on ‘synthetic pond water’. Infrared and proton n.m.r. measurements have been made on the organic material extracted from GCOS pondwater. This information on tailings water is relevant to the large accumulation of tailings that has become known as the ‘pondwater problem’ in connection with extraction of bitumen from mined Alberta oil sands.