use nonfreshwater sources such as seawater (if located on the coast), brackish water from wells or estuaries, agricultural runoff, “produced water” from oil and gas drilling operations, or treated municipal wastewater (Veil, 2007). The water consumption is often of concern with thermal power plants; however, the water use92 can also be an issue, as cooling water is returned to the source at a higher temperature.

The water-use impacts of future nuclear plants will depend on where the new nuclear plants are sited (for example, along a coastline versus the arid Southwest) and what cooling technologies are employed. If deployed after 2020, alternative cooling technologies such as dry cooling93 or hybrid cooling94 could reduce water use compared to current technologies. Dry cooling has been used for some coal-fired plants,95 but at present no commercial nuclear plants have been constructed using this technology; it is likely to have significant disadvantages, including higher costs, higher operating power requirements, and reductions in plant efficiency and capacity during hot-weather periods. Hybrid cooling may be used in several evolutionary nuclear plants proposed for construction in the United States in the near term, including the new reactor planned by UniStar for the Calvert Cliffs site in Maryland (Pelton, 2007).

Waste Management and Disposal

Electricity production by means of nuclear power results in several types of radioactive waste, all of which must ultimately be disposed of. They include waste from uranium mining and fuel production (just discussed); waste produced during operations (such as contaminated gloves, tools, water-purification filters and resins, and plant hardware); and used fuel. Additional waste will be generated when the plant itself is decommissioned.

The construction of new nuclear plants in the United States will cause the production of additional used fuel, other operational waste, and decommission-

92

Water use refers to the amount of water used by the plant but returned to the source; water consumption refers to the amount of water used by the plant and not returned to the source.

93

Dry cooling is usually accomplished with mechanical-draft air-cooled condensers, to which a turbine’s exhaust steam is ducted through a series of large ducts, risers, and manifolds.

94

Hybrid cooling systems typically consist of a dry cooling system operating in parallel with a conventional closed-cycle wet cooling system.

95

For example, the Kogan Creek power station in Australia, a 735 MW coal-fired plant, uses dry cooling.



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