The operator of Japan's crippled Fukushima nuclear plant will as early as this week begin removing 400 tonnes of highly irradiated spent fuel in a hugely delicate and unprecedented operation fraught with risk.
Carefully plucking more than 1,500 brittle and potentially damaged fuel assemblies from the plant's unstable Reactor No. 4 is expected to take about a year, and will be seen as a test of Tokyo Electric Power Co's ability to move ahead with decommissioning the whole facility - a task likely to take decades and cost tens of billions of dollars.
If the rods - there are 50-70 in each of the assemblies, which weigh around 300 kg (660 pounds) and are 4.5 meters (15 feet) long - are exposed to air or if they break, huge amounts of radioactive gases could be released into the atmosphere.
And that would be catastrophic for the west coast of the US, not to mention Japan. To read more, click here.