If we haven’t had a meltdown in Japan by now, the perfectly-named Malcolm Grimston tells CNN, we’re not likely to see one at all. Unlike in Chernobyl, the Japanese shut down their reactors and started cooling them down. At the Fukushima Daiichi plant where fears were highest of a catastrophe, authorities gave up on saving the reactor for later use at all and began pumping seawater into the cooling system to avert a meltdown. The danger has not yet passed, but we’re almost certainly beyond the point of a catastrophic breach and are instead looking at the best path to a quick and reasonably safe shutdown:

That does not mean that the danger has passed:

Workers continued efforts to cool down fuel rods inside two nuclear reactors Sunday as a Japanese government official warned that a second explosion could occur at the plant.

And the plant might have yet another explosion of built-up hydrogen gas that the rapid attempts to shut down the reactor and the failure of cooling systems has produced:

“There is a possibility that the third reactor may have hydrogen gas that is accumulating in the reactor (that) may potentially cause an explosion,” he said.

An explosion caused by hydrogen buildup Saturday blew the roof off a concrete building housing the plant’s No. 1 reactor, but the reactor and its containment system were not damaged in the explosion.

Edano said the No. 3 reactor would also likely withstand a similar blast, noting that workers had already released gas from the building to try to prevent an explosion.

As one expert warned, the Japanese are not out of the woods yet. No one can get close enough to the cores to precisely determine their conditions. But shutting down the reactors and scrapping at least one of them has put them closer to a safe landing in this crisis.

Update: As if the beleaguered Japanese didn’t have enough problems:

A volcano in southwestern Japan erupted Sunday after nearly two weeks of relative silence, sending ash and rocks up to four kilometres (two and a half miles) into the air, a local official says. …

The 1,421-metre (4,689-feet) Shinmoedake volcano in the Kirishima range saw its first major eruption for 52 years in January. There had not been any major activity at the site since March 1.

The volcano erupted in January after 52 years of silence. Authorities had already restricted access to the area, but now Japan has to worry whether the ash might interfere with air travel, which would impact international rescue and recovery assistance.