Dangers of nuclear power

I have devoted more space to explaining the dangers of nuclear power than to the consequences of using fossil fuels, because while the consequences of carbon emission are well understood, the inexhaustible nature of thermal power and the implications of terrorists using breeder reactor fuel for military purposes are largely unknown. 

Other people arc concerned about the dangers of nuclear power. The radiation released and radioactive wastes produced by nuclear power plants have made them unpopular in the United States. It is not clear what the future of nuclear power plants in the United States will be. 

The potential dangers of nuclear power were tragically demonstrated by the accidents at Three Mile Island, Pennsylvania (1979), and Chernobyl in the former U.S.S.R. (1986). Both accidents resulted from the loss of coolant to the reactor core. The reactors at Three Mile Island were covered by concrete containment buildings and therefore released a relatively small amount of radioactive material into the atmosphere. But because the Soviet Union did not require containment structures on nuclear power plants, the Chernobyl accident resulted in 31 deaths and the resettlement of 135,000 people. The release of large quantities of 1-131, Cs-134, and Cs-137 appears to be causing long-term health problems in that exposed population. 

However, skyrocketing and fluctuating prices for oil and natural gas in 2004-2008, combined with growing demand for electricity and concerns about the environmental dangers of fossil fuel emissions, have brought about renewed interest in the potential of nuclear power. 

Energy production as well as other human activities are always connected with risk taking. Radiation, and everything related to it, generates a fear not easily understood. This probably comes from the invisibility of the danger and relation to the bomb. Therefore the safety of nuclear power must be compared with the safety of alternative ways of generating electricity. 

Although construction and operation of nuclear power plants are closely monitored and regulated by the NRC, an accident, though unlikely, is possible. The potential danger from an accident at a nuclear power plant is exposure to radiation. This exposure could come from the release of radioactive material from the plant into the environment, usually characterized by a plume (cloud-like) formation. The area the radioactive relea.se may affect is determined by the amount released from the plant, wind direction and speed and weather conditions (i.e., rain, snow, etc.) which would quickly drive the radioactive material to the ground, hence causing increased deposition of radionuclides. 

NPP Safety versus Radioactive Waste Management. The basic danger potential of nuclear power plants and radioactive waste repositories is similar the threat of leakage of radioactive materials into the biosphere. Thus, there are some similarities in the safety approaches, too. For example, the safety objective in both areas is achieved as long as the radioactive materials are confined. When high reliability in confinement is required the multiple barrier principle is a natural solution. The differences between nuclear power plant safety and repository safety will be discussed in greater detail later in this paper. 

The defence in depth concept provides an overall strategy for safety measures and features of nuclear power plants. When properly applied, it ensures that no single human or mechanical failure leads to danger to the public, and even combinations of failures that are only remotely possible would lead to little or no injury. Defence in depth helps to establish that the three fundamental safety functions (controlling the power, eooling the fuel and confining the radioactive material) are preserved, and that radioaetive materials do not reach people or the environment. 

---