Will it take years and decades to clean or will it take hundreds or thousands of years like a nuclear meltdown?
Well, when an entire ecosystem is damaged by oil spills, it still suffers long term disruption. If an entire segment of the foodchain is knocked out, species can die out very quickly, and restructuring the prior balance of the ecosystem may take longer than "just" decades, if even possible at all.
On the flip side, the effects of nuclear radiation depend very much on the characteristics of the leak. Although we might consider an area to be "uninhabitable for a thousand years" by
human safety standards, that doesn't mean life in that area is utterly impossible,
period. Not to discount the dangers of fallout, but between it and oil spills, neither are very good for the ecosystem, no matter how you cut it.
In terms of per-megawatt-hour produced, nuclear energy has far lower casualty rates (eg: from accidents) compared to oil, and especially coal. Nuclear (based on uranium) is
not an ideal fuel source; there are lots of problems with it and the arguments against it are perfectly valid (safety systems, contamination, fuel waste, etc). But you simply can't say that oil, coal, and natural gas are therefore
better: they too have their own problems, including health hazards (from pollution), working hazards (from mining), pollution hazards (spills and carbon dioxide), and so on. Not to mention the politics that are tied up in oil production, and depletion of coal and natural gas reserves.
What the world really needs is more funding to take what we've learned from nuclear power, and develop new era energy sources, like cold fusion or thorium reactors. Thorium especially is a promising technology, because it can provide the same magnitude of energy output as uranium reactors, does
not depend on a pressure vessel (which is why uranium nuclear plants are prone to explosion), it self-moderating and does not require external cooling or safety mechanisms, and is far more abundant in nature than the isotope of uranium needed for current reactors. And thorium reactors can be much smaller (researchers have suggested about the size of an average gas station, to power a local community).
What happened in Fukushima really should never have happened, in the sense that it was an unlucky combination of 1) unforseeable tsunami damage, and 2) years of government and financial mismanagement, prior to the March 11 earthquake (no doubt thanks in part to Japan's stagnating economy and general government incompetence since the bubble burst in the 90's). You simply do not run a nuclear reactor if you are willing to cut corners and skip inspections to save money, and you do not continue to run a 30-year-old+ Mark I reactor past its useful lifespan, when nuclear technology has advanced (to Mark II and III, and soon IV), without rethinking contingency scenarios. The
extent of Fukushima is due to
human error; it does
not mean there is a fundamental flaw with nuclear technology that cannot be controlled (although compared to aforementioned thorium, we can do a lot better).
In reality, though, Fukushima is an example of Japanese tendency of over-engineering. Despite a magnitude 9.0 earthquake, devastating tsunami, multiple power failures, steam explosions and high-temperature fires that could compromise structural integrity, multiple reactors already at the end of their useful lifespan, and government and TEPCO incompetence, it is nothing short of amazing that the Fukushima reactor vessels did
not catastrophically rupture as many feared it might. And the little ionizing radiation that escaped was quickly dispersed into the upper atmosphere (distributed in steam, rather than encapsulated in debris), or heavy water in the sea.
Combined with regular testing for contaminated food sources, and health screening for potentially affected populations, I think in the years to come Fukushima may prove to be a lot less damaging than most oil spills. More importantly, it will serve as an important reminder of what we
can do to keep nuclear power safe: utilize newer reactor designs, retire old reactors that have completed their useful lifespan, reconsider contingency plans, and standardize personnel, government, and international response procedures for dealing with scenarios.
You may not like nuclear power, but the fact is that the modern world relies on it for a significant part of its energy supply. We cannot simply shut off all nuclear plants and replace them with pre-existing oil/coal/natural gas technology; trying to do so would seriously disrupt everything from our daily lives, to foreign policy. Nuclear (uranium) is not the answer, but you shouldn't fall into anti-nuclear fear-mongering and dismiss it altogether. Say
no instead, to outdated nuclear reactor designs, to sub-standard regulations and oversight, and to poor education. The danger of playing into the fear-mongering is that the general public may become so entrenched in anti-nuclear views as to stagnate or even block developmeng of newer technologies like thorium reactors!
[Postscript: to readers familiar with nuclear reactor technologies, you may realize that I have generalized a lot in the descriptions of nuclear power, to the point that they may not be the most technically accurate way of explaining nuclear technology; but it's only a generalization within an opinion, not a scientific lecture; anyone inclined to educate themselves on the issue has far better resources online and elsewhere than a forum devoted to Japanese culture!]
