Large volumes of produced water are generated during production of heavy crude oil and large volumes of surface water often are needed to produce, transport, and upgrade heavy crude oils and bitumens. The most important alternatives for managing produced and process waters include volume minimization, underground injection, discharge to surface waters, and beneficial reuse. Produced and process waters often contain high concentrations of inorganic salts, metals, hydrocarbons, and organic acids. They may cause ecological damage if discharged untreated to surface waters or soils. Salts harm terrestrial vegetation and naphthenic acids and polycyclic aromatic hydrocarbons are toxic to aquatic organisms. Most produced water is either reinjected into a non-producing formation or used for enhanced oil recovery (EOR) technologies, such as cyclic steam stimulation (CSS) and steam-assisted gravity drainage (SAGD), or bitumen transport and upgrading by slurry pumping and alkaline extraction. Before use or discharge to surface waters, the produced water must be treated to remove dissolved salts, organic acids, hydrocarbons, and suspended solids. Wastes from cold heavy oil production with sand (CHOPS) usually are pumped to stock tanks where the gas, water, oil, and solids are separated and the produced water is piped to a disposal well. The solids are stored in tailings ponds. Wastes produced during processing oil sands bitumen from surface mining with hot alkaline water also are stored in tailings ponds. Water may be decanted from the tailings ponds and reused or reinjected into a non-producing formation. Tailings ponds containing mature fine tailings may be reclaimed as lake basins. Several new technologies are being developed to remove salts, organic acids, and hydrocarbons, and to break stable heavy oil-water emulsions so that produced and process waters can be reused without damaging production equipment and producing formations or discharged without harming the environment.

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