Japan’s nuclear authority will allow Fukushima's nuclear power plant operator, TEPCO, to build an underground ice wall isolating radioactive water build-up. This is despite earlier concerns that the wall might cause the ground to sink.
The Nuclear Regulation Authority (NRA) no longer has reservations
about the 32 billion yen (US$314 million) government-funded
project, in which a giant “wall of ice” is to be built
around the crippled Fukushima No. 1 nuclear plant’s four
reactors, Kyodo news agency reported.
The plan, which involves 1.5 kilometers of pipes with coolant
powerful enough to make the earth around it freeze, earlier
raised concerns that it could cause trouble by making the ground
near the reactors less stable.
TEPCO officials have, however, persuaded NRA experts that the
ground around the ice wall may sink only up to 16 mm, posing no
threat to its stability.
“I think we have been able to confirm today the scale of
ground sinking, which is what we have most feared as side effects
of building the wall,” NRA Commissioner Toyoshi Fuketa told
Kyodo.
While accepting the operator’s explanation, the NRA still has
issues to discuss with TEPCO, which include ways to accurately
measure the level of radioactive water accumulating inside the
reactor buildings.
The issue of contaminated groundwater seeping through the ground
and into the ocean has for years been one of the major problems
faced by TEPCO.
Some 350,000 tons of water have already accumulated in tanks
beside the plant, which are becoming increasingly difficult to
maintain. A water purification system was introduced a year ago,
but has suffered constant malfunctions and is currently in
shutdown. The system is capable of cleaning up to 750 tons of
water a day.
TEPCO recently rerouted water flows around the plant straight into
the ocean in an attempt to prevent them from being contaminated.
Earlier in April, the manager of the stricken Fukushima nuclear
power plant, TEPCO’s Akira Ono, admitted that the company still
doesn't have “full control” over radioactive leaks in some parts of the plant.
TEPCO is now hoping that the giant ice wall will isolate the
problem. While this engineering solution has been used before,
such as for preventing the flooding of Russia’s St. Petersburg
underground system, the Fukushima ice wall may be the first
project of such a large scale.