TOKYO — Even before the troubled Fukushima nuclear plant has been brought under control, two rival conglomerates likely to be part of an eventual cleanup are estimating that the effort could take 10 years — or 30.
T.V.A. Considers Improvements for 6 U.S. Nuclear Reactors (April 15, 2011)
Nuclear Cleanup Plans Hinge on Unknowns (April 15, 2011)
The widely divergent outlooks underscore the basic uncertainties clouding any forecast for Fukushima: when cooling stems will be restored and radiation emission halted; how soon workers can access some parts of the plant; and how bad the damage to the reactors, their fuel, and nearby stored fuel turns out to be. The United States Nuclear Regulatory Commission has warned that at least one reactor’s fuel may even have leaked out of the reactor pressure vessel, something that has never before happened in a nuclear accident.
A global team led by Hitachi said Thursday that it would take at least three decades to return the site to what engineers refer to as a “green field” state, meaning within legal limits of radiation for any residents. Toshiba, Japan’s biggest supplier of nuclear reactors, said it could take as little as 10 years
http://www.nytimes.com/2011/04/15/world/asia/15cleanup.html