Tokyo Electric Power Co. (TEPCO) just issued a new report on the severity of the damage to the reactors at Fukushima Units 1, 2 and 3, and it is worse than previously thought. The Wall Street Journal reported this morning:
The stricken Fukushima Daiichi nuclear-power plant came a lot closer to a full “China Syndrome” meltdown than previous company analyses had indicated, though there is no danger of further damage now, plant operator Tokyo Electric Power Co. said Wednesday.
The nuclear-fuel rods in reactor No. 1 likely melted completely, Tepco and the Japanese government said for the first time—burning a hole through one surrounding vessel and eating through up to three-quarters of the concrete base at the bottom of a second containment vessel meant as a last barrier between the radioactive core and the outside world.
Although TEPCO still maintains that there is no longer any danger from the three crippled reactors, there is a line at the end of the Wall Street Journal article that is a little concerning:
In a safety assessment last month, Tepco said the biggest risk to the plant remains another large tsunami, which could destroy water-supply lines and prevent further cooling of the reactors. The company stressed, however, that the availability of multiple water-supply sources, including on-site fire trucks, reduces the risks.