Fukushima deep in hot water
In the first hours of March's accident at the Fukushima Daiichi nuclear power plant, workers rushed to flood three damaged reactors with sea water to prevent a catastrophic meltdown. Three months later, water is still being pumped into the cores and has become the biggest obstacle to cleaning up the site.
http://www.nature.com/news/2011/110607/full/474135a.html