Mysterious plumes of white, black, and grey smoke have billowed out of the Fukushima I nuclear power plant, prompting speculation about the status of the devastated reactors.
Tokyo Electric Power Co. via Kyodo News / AP
Smoke plumes continue to rise from parts of Japan's devastated Fukushima I nuclear plant. On Wednesday, black smoke suddenly billowed up from reactor No. 3, causing workers to evacuate the area and stopping work at the plant for a few hours. Crews later returned, and officials said radiation levels did not spike during the incident. But smoke has been a continuing problem at Fukushima I (also called Fukushima Daiichi) – white and grey plumes have erupted at the plant a number of times this week.
What’s causing this smoke? Is it a matter of concern?
In general, workers are making progress stabilizing Fukushima I, said the International Atomic Energy Agency on Wednesday. Electricity has returned – in some measure – to most of the plant’s six reactors. Control room instruments are now powered at all except No. 3, for instance.
But seeing light at the end of the tunnel is not the same thing as reaching open air. The bursts of smoke are among pieces of evidence indicating that Fukushima I is not yet under complete control.
“The overall situation remains of serious concern,” said Graham Andrew, special advisor to the IAEA Director General for Scientific and Technical Affairs.
At this point, officials do not know how serious the smoke bursts are because they are not certain what their cause is.
As Japanese workers have powered up reactors in recent days, shorts or other electrical problems could have ignited debris from last week’s containment building explosions, said David Lochbaum, director of the nuclear safety project at the Union of Concerned Scientists, in a Wednesday phone briefing for reporters.