A nuclear meltdown would be a local catastrophe requiring evacuation (and likely permanent abandonment) of the surrounding communities, but that risk is not substantially different in magnitude from a burst hydroelectric dam, or from the aggregate harm of continuing to pollute our atmosphere with fossil fuel waste products..
Certainly, nuclear energy requires strict regulation, careful facilities planning, and myriad other equally important practical considerations for administrating the industry safely so that its risks are minimized. However, the emotional objection to peaceful uses of nuclear power is based on incorrect assumptions about what those risks actually are, as well as on the illogical association of the beneficial uses of the technology with its destructive potential used in weapons of war.
Ethical Perspective:
In the case of nuclear power, the ethical considerations are closely related to the logical analysis. Once it is established that the emotional objection to nuclear power on overall principle is unsustainable, the ethical analysis pertains more to issues of deciding where to employ it and how to regulate it to ensure that it does not impose unreasonable, and therefore, unethical risks to some for the benefit of others.
While nuclear explosion is not a risk associate with nuclear reactors, human error and/or technical malfunction can still threaten the existence of local communities. In the event all the layers of safety measures and safeguards failed and a nuclear reactor core actually melted down, the resulting release of radiation would render the nearby land completely uninhabitable for hundreds if not thousands of years afterwards (Gundersen, 1999). Individuals who failed to evacuate in time might suffer radiation exposure.
Reactors in the United States are protected in concrete containment buildings that are far less susceptible to breaching, even in a meltdown, than the Soviet reactor in Chernobyl...
In the exceptionally unlikely scenario of a similar explosion and breach of a concrete containment building of a U.S. reactor, the danger to local communities would increase, by virtue of the release of vaporized radioactive particles into the atmosphere, which then fall back to earth. While this increases the risk to the local communities, (and extends the risk beyond the borders of a meltdown without a breach), it does not change the fundamental nature of the risk.
Conclusion:
All human endeavors of large scale involve certain risks. Within large-scale engineering projects such as bridges, tunnels, dams, and even ordinary interstate highways, a certain number of injuries and deaths are expected and calculated in advance according to formula. Likewise, even routine modern conveniences entail risk, both to one's self as well as to others: a generally accepted estimate of vehicular deaths in the U.S. is 100,000 killed in motor vehicles each year. It is likely that more than half of those killed were entirely innocent, because multiple vehicle fatal accidents usually involve one at-fault driver, and even single vehicle accidents often involve passengers, many of whom are children.
We do not prohibit vehicular travel, nor should we worry about using nuclear energy in principle. Like other human endeavors, nuclear power generation requires appropriate management and oversight to ensure that it is conducted as safely as possible and that its legitimate risks are minimized to the greatest extent possible. That, rather than whether or not it should be used, should be the focus of ethical concerns.
References
Gundersen, P. (1999) the Handy Physics Answer Book.
Barnes & Noble: New York
Rennie, R. (2003) the Facts on File Dictionary of Atomic and Nuclear Physics.
Checkmark Books: New York
