The operators of the triple-meltdown site at Fukushima keep talking about achieving a "cold shutdown" of the three blown-out nuclear reactors there -- getting them down below boiling water temperatures. But there are new reports indicating that far from being "shut down," one or more of the reactors is still undergoing nuclear fission:

The company, known as Tepco, began spraying boric acid on the No. 2 reactor at 2:48 a.m. Japan time to prevent accidental chain reactions. Tepco said it may have found xenon, which is associated with nuclear fission, while examining gases taken from the reactor, according to an e-mailed statement today.

"Given the signs, it’s certain that fission is occurring," Junichi Matsumoto, a general manager at Tepco who regularly talks to the media, told reporters in Tokyo today. There’s been no large-scale or sustained criticality and no increase in radiation, he said.

To those who have been following the tragic accident since last March, this is no surprise. Lately they've been turning up radioactive iodine in tests of rice grown near the plant. Radioactive iodine has a half-life of only eight days, and so there must still be "criticality" somewhere in the Fukushima complex.

Coupled with new revelations of much higher radiation releases from the original March explosions and massive leaks of radioactive water to the ocean, the news from that quarter is as depressing as it has been in many months.