5.5 Energy Production and Mining
Carolina, nuclear power plants choose between two primary options for discharging heated water: discharge heated water directly into a water body or build a cooling tower that will evaporate and cool water. Duke Energy’s Brunswick Nuclear Plant near Southport transports heated water along a canal until the water is eventually discharged ofshore. Duke Energy’s Harris Nuclear Plant cools water with a cooling tower where most water is evaporated. Te small amount of col- lected water that is not evaporated is returned back to Harris Reservoir. Returning heated water directly to a water body changes the water quality of the receiving water body, particularly in the area of the discharge, and creates unnaturally warmer water conditions. Other water quality parameters such as DO, salinity, turbidity, pH, and water chemistry parameters may also difer from ambient conditions. Such modifcations can afect the species inhabiting the area of the discharge. Use of cooling towers can eliminate the discharge of heated water and deleterious efects on receiving waters. However, water evaporates from cooling towers at a much faster rate than normal and that water is no longer available to contribute to downstream fows. By withdrawing large volumes of water for cooling, aquatic organisms can be impinged or entrained, resulting in injury or death. Impinged organisms can be caught against screens used to prevent transport of larger debris. Continual water pressure against organisms can lead to eventual death or injury. Additionally, some organisms are small enough to pass through screens and will be entrained in the water transported to the nuclear reactors for cooling where they can be subjected to harsh conditions, nearly always leading to death. Water intake structures use various techniques to reduce the number of organisms that are impinged or entrained. Tese include slow intake velocities, fne mesh screens, and period- ically backwashing screens. In the future, there is potential for additional nuclear power plants or expansion of exist- ing plants. In addition to the potential impacts described previously and terrestrial land conversion impacts, future nuclear plants will potentially impact river fows due to their dependence on water for cooling. Such river fow impacts could result from creating an impoundment and afecting a section of free-fowing water, pumping water from a river to maintain sufcient water in an impoundment, or expanding an existing reservoir and afecting the timing and volume of downstream fows due to increased demand for cooling water.
5.5.7 Solar Energy—Anticipated Impacts Electricity produced from solar power has increased greatly in North Carolina in recent years. Solar electricity is produced in two primary ways: concentrated solar power (CSP)
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2015 NC Wildlife Action Plan
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