TOKYO (AP) - Japan’s nuclear watchdog said Wednesday that the crippled
Fukushima power plant is probably leaking contaminated water into the ocean,
a problem long suspected by experts but denied by the plant’s operator.
Officials from the Nuclear Regulation Authority said a leak is “strongly
suspected” and urged plant operator Tokyo Electric Power Co. to determine
where the water may be leaking from and assess the environmental and other
risks, including the impact on the food chain. The watchdog said it would
form a panel of experts to look into ways to contain the problem.
The watchdog’s findings underscore TEPCO’s delayed response in dealing with
a problem that experts have long said existed. On Wednesday, the company
continued to raise doubts about whether a leak exists.
TEPCO spokesman Noriyuki Imaizumi said the increase in cesium levels in
monitoring well water samples does not necessarily mean contaminated water
from the plant is leaking to the ocean. TEPCO was running another test on
water samples and suspects earlier spikes might have been caused by
cesium-laced dust slipping into the samples, he said. But he said TEPCO is
open to the watchdog’s suggestions to take safety steps.
The Fukushima Dai-ichi plant was ravaged by the March 2011 earthquake and
tsunami and has since struggled with leaks of water used to cool the
reactors, hampering decommissioning efforts.
Marine biologists have warned of the possibility of continuous leak of
radioactive water into the sea via an underground water system, citing high
levels of radioactivity in fish samples taken near the plant.
Since May, TEPCO has reported spikes in cesium levels in underground water
collected from a coastal observation pit.
, while the water-soluble element strontium showed high levels in seawater
samples taken in areas just off the coast of the plant. The company says
most of the contamination has been there since the 2011 accident.
But the Nuclear Regulation Authority said Wednesday that samples from both
the pit water and coastal seawater indicated that contaminated underground
water likely had reached the sea.
Watchdog chairman Shunichi Tanaka said he thinks that the seawater
contamination has been happening since the accident, but that it was worst
early in the crisis.
“What’s most important is to minimize the leak to the outside and reduce the
impact on the human society,” he said.
TEPCO says that it has taken steps to prevent seawater contamination in
areas near the plant, but that it is impossible to completely prevent the
contamination from spreading into wider areas.
Atsunao Marui, underground water expert at the National Institute of
Advanced Industrial Science and Technology, said there is a possibility of
new leaks from reactor buildings. He said TEPCO will have to expand its sea
water sampling and its investigation of the underground water system to
assess the extent of possible contamination.
“It is important to apply several layers of protection,” he told NHK
The plant, which still runs on jury-rigged systems to cool the reactors, has
been plagued by problems, including repeated leaks of contaminated water
from storage tanks. Managing the contaminated water and its storage has been
a chronic headache.
“When something unexpected happens, we can only take stopgap measures, which
shows how unstable Fukushima Dai-ichi still is,” Tanaka said. “Given the
situation, we can only use the best of our wisdom and do what we can.”