TOKYO – After notching a rare victory by
stopping highly radioactive water from flowing into the Pacific, workers at
Japan’s flooded nuclear power complex turned to their next task: injecting
nitrogen to prevent more hydrogen explosions.
Nuclear officials said there was no
immediate threat of explosions like the three that rocked the Fukushima
Dai-ichi plant not long after a massive tsunami hit last month, but their plans
are a reminder of how much work remains to stabilize the complex.
Workers are racing to cool down the
plant’s reactors, which have been overheating since power was knocked out by
the 9.0-magnitude earthquake and tsunami that killed as many as 25,000 people
and destroyed hundreds of miles of coastline on 11 March.
Unable to restore normal cooling
systems because water has damaged them and radioactivity has made conditions
dangerous, workers have resorted to pumping water into the reactors and letting
it gush wherever it can.
Superheated fuel rods can pull
explosive hydrogen from cooling water, so now that more water is going into the
reactors to cool them down, the concern is that hydrogen levels are rising.
Technicians started pumping
nitrogen into an area around one of the plant’s six reactors Wednesday night to
counteract the hydrogen.
They want to prevent hydrogen
explosions at all costs because they could spew radiation and damage the
The nitrogen pumping has its risks
too, but Japan’s Nuclear and Industrial Safety Agency approved it as a necessary
measure to avoid danger, spokesman Hidehiko Nishiyama said. The injection could
release radioactive vapour into the environment, but no one is living in a
12-mile evacuation zone around the plant.