That is how far the No.1 reactor at Fukushima has to go before containment is breached.
Not very reassuring.
TEPCO has made the latest analysis to judge to what degree the fuel has cooled, as well as to ascertain if it can achieve its year-end target of a cold shutdown of the reactors, as stipulated in the timetable the utility company and the government have compiled to bring the nuclear crisis under control.
Following the March 11 earthquake and tsunami, water injection at the No. 1 reactor was suspended for about 14 hours, resulting in damage more serious than in the Nos. 2 and 3 reactors, which had water injection suspended for six to seven hours, according to TEPCO.
The nuclear fuel at the No. 1 reactor melted as its temperature reached nearly 3,000 C at one time, TEPCO estimated. In the No. 1 reactor, TEPCO believes, almost all of the about 68 tons of fuel melted. This has not only seriously damaged the bottom of the steel pressure vessel enough to create holes, but the fuel has also fallen to the concrete bottom of the containment vessel, eroding it by up to 65 centimeters.
We really do not need nuclear power as the danger involved far exceeds any benefit it may provide otherwise.
Tokyo Electric Power [Tepco] said in a report that fuel inside reactor No 1 appeared to have dropped through its inner pressure vessel and dropped into the outer containment vessel, indicating that the accident was more severe than at first thought.
The revelation that the plant may have narrowly averted a disastrous "China syndrome" scenario comes days after reports that the company had dismissed a 2008 warning that the plant was inadequately prepared to resist a huge tsunami .
Tepco revised its view of the damage inside the No 1 reactor – one of three that suffered meltdown soon after the 11 March disaster – after running a new simulation of the accident.
It would not comment on the exact position of the molten fuel, or on how much of it is exposed to water being pumped in to cool the reactor. More than nine months into the crisis, workers are still unable to gauge the damage directly because of dangerously high levels of radiation inside the reactor building.