The New York Times reports that Tokyo Electric Power Company (Tepco) has admitted for the first time that the melted core at its Unit 1 reactor at the devastated Fukushima Daiichi nuclear power plant has likely "bored" into the concrete floor of the primary containment, coming precariously close to an outer steel barrier, the final line of defense against even more catasatrophic radioactivity releases into the external environment. A critic describes Tepco's latest admission as "still an overly optimistic simulation." Hiroaki Koide, of the Kyoto University Research Reactor Institute, warns "I have always argued that the containment is broken, and that there is the danger of a wider radiation leak."
Speaking of overly optimistic nuclear disaster simulations, Greenpeace has strongly condemned Japanese government nuclear emergency preparedness for its inadequate "Speedi" radioactive plume computer code. The code only covers a 10 km area, whereas Greenpeace has documented Fukushima fallout 60 km downwind that should -- under international standards -- require evacuation of the population. Greenpeace also documents that actual nuclear catastrophes could be 10,000 times worse than those assumed by Speedi.