Problems of Nuclear Reactors核反应堆的问题
Concerns about the safety of nuclear fission reactors include the possibility of radiation-releasing nuclear accidents, the problems of radioactive waste disposal, and the possibility of contributing to nuclear weapon proliferation. 关于核裂变反应堆安全性的担忧包括核事故释放辐射的可能、放射性废物处理的问题，以及可能助长核武器扩散的可能。
Although most technical analyses have rated nuclear electricity generation as comparable in safety to coal-powered generation, the low public confidence in nuclear power has blocked further development of nuclear power in the United States. No new nuclear power plants have been ordered since the Three Mile Island accident, and some partially completed projects have been abandoned. As of 1990 about 20% of electricity in the U.S. was generated by nuclear plants, compared to about 75% in France. 尽管大多数技术分析认为核能发电的安全性与燃煤发电相当，但公众对核能的低信心已阻碍了美国核能的进一步发展。自三里岛事故以来，美国未再下令建设新的核电站，一些已部分建成的项目也被放弃了。截至1990年，美国约有20%的电力由核电站发电，而法国则为约75%。
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Reactor Accidents反应堆事故
The nuclear accident at Chernobyl was the worst nuclear accident to date, spewing about 100 million Curies of radioactive material into the environment. By contrast, the accident at Three Mile Island released only some 15 Curies. Though its health effects were minimal, Three Mile Island did perhaps irreparable damage to the level of public confidence in nuclear reactors for electric power production in the United States. 切尔诺贝利核事故是迄今为止最严重的核事故，释放了约100 million居里（10亿居里）的放射性物质进入环境。相比之下，三里岛事故仅释放了约15居里。尽管其健康影响微乎其微，三里岛事故可能对美国核电站发电的公众信心造成了不可挽回的损害。
Preceding these two high-profile accidents are a number of nuclear accidents with radiation release. These include accidents at the Fermi I reactor near Detroit, at the NRX reactor at Chalk River, Canada, at the Windscale reactor in England, and the SL-1 Reactor at Idaho Falls. 在这些两起备受关注的事故之前，还发生了一系列核事故，涉及放射性物质的释放。这些包括密歇根州底特律附近费米I反应堆的事故、加拿大查尔克河NRX反应堆的事故、英国温斯莱德反应堆的事故，以及爱达荷瀑布的SL-1反应堆的事故。
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Radioactive Waste Disposal放射性废物处置
The nuclear fission of uranium-235 produces large quantities of intermediate mass radioisotopes. The mass distribution of these radioisotopes peaks at about mass numbers 95 and 137 , and most of them are radioactive. The most dangerous for environmental release are probably cesium and strontium because of their intermediate half-lives and propensity for reconcentration in the food chain. 铀-235的核裂变会产生大量中等质量的放射性同位素。这些同位素的质量分布峰值出现在约质量数95和137处，其中大多数都是放射性的。对环境释放而言，可能最危险的是铯和锶，因为它们的半衰期适中，并且容易在食物链中重新集中。
When spent fuel assemblies are removed from nuclear reactors, they are transported to "swimming pool" storage facilities to dissipate the heat of decay of short-lived isotopes as well as for isolation from the environment. The long term disposal of these wastes remains a major problem. It was assumed that these wastes would be encased in glass and placed in geologic disposal sites in underground salt domes. The site at Yucca Mountain was chosen as a first site, but both technical and political problems have thus far blocked its implementation. 当使用过的燃料组件从核反应堆中移除时，它们被运输到称为'游泳池'的储存设施中，以便散发短寿命同位素衰变产生的热量，并与环境隔离。这些废物的长期处置仍然是一个主要问题。曾假设这些废物将被封装在玻璃中，并放置在地下盐层的地质处置场所。尤卡山被选为第一个候选地点，但技术性和政治性问题至今仍阻碍了其实施。
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Nuclear Weapons Proliferation核武器扩散
One concern about nuclear reactors is that the fuel could be diverted for the production of nuclear weapons. While the the uranium fuel is enriched to only 3-5% and could not easily be further separated to the >90% U-235 needed to produce a bomb, the spent fuel elements contain plutonium-239. The plutonium could be separated chemically and diverted to nuclear weapons production. Security concerns about the plutonium has thus far blocked any reprocessing of fuel from nuclear power plants. 关于核反应堆的一个担忧是燃料可能被用于制造核武器。虽然铀燃料仅被浓缩到3-5%，难以进一步分离出超过90%的铀-235，以制造炸弹所需，但使用过的燃料元件中含有钚-239。这种钚可以被化学分离并用于核武器生产。因此，对钚的安全担忧迄今为止阻止了核电站燃料的再处理。
A similar concern exists for fast breeder reactors, where the breeding process produces plutonium-239 for future generations of reactors. 类似的问题也存在于快中子增殖反应堆中，其中增殖过程会产生用于未来反应堆的钚-239。
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