Newest terrifying thing at the Fukushima Daiichi plant: A breach in a trench is leaking highly radioactive water into the surrounding ocean. Japanese utility TEPCO tried over the weekend to use concrete to plug the leak. When that failed, they went for the next most logical solution: a mixture of "132 pounds of sawdust, 18 pounds of polymer and three bags of shredded newspaper."

That didn't work either. Did we learn nothing from that time BP tried to plug an oil leak by throwing trash in it?

Plan C is to put up a "silt fence" in the ocean — a sort of floating curtain intended to contain the radioactive seawater leaking from the plant.

In terms of net emissions of radioactive material into the environment, this leak could soon be dwarfed if Tepco vents contaminated water by deliberately releasing it into the ocean. The Fukushima-bordering sea could be looking at 11,500 tons of water that is already 100 times the legal limit for radioactivity. Tepco deems that "relatively low" and they're right — seawater is already very slightly radioactive to begin with.

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