Final answer:
Nuclear power plants impact the environment through various stages, including the mining and refining of uranium ore, construction, and the generation of radioactive wastes.
Step-by-step explanation:
Nuclear power plants have various impacts on the environment from different perspectives and stages. The mining and refining of uranium ore, as well as the production of reactor fuel, require a significant amount of energy. The construction of nuclear power plants also demands a large amount of metal, concrete, and energy. However, the main environmental challenge associated with nuclear power is the generation of radioactive wastes, such as uranium mill tailings, spent reactor fuel, and other radioactive materials. These wastes have long half-lives and pose a threat to human health for thousands of years. The U.S. Nuclear Regulatory Commission regulates the operation of nuclear power plants and the handling, transportation, storage, and disposal of radioactive materials to protect human health and the environment.