Tokyo Electric Power Co. came under increasing pressure from the government Monday to address recent water leaks and power outages at the meltdown-stricken Fukushima No. 1 nuclear plant as nine experts who investigated the crisis said the new watchdog’s oversight was still too lax.
“If these kinds of incidents continue to occur, the very process of decommissioning the reactors could be affected,” industry minister Toshimitsu Motegi told Tepco President Naomi Hirose at a meeting.
Motegi said the public is “greatly” concerned about the situation and ordered Tepco to take steps to ensure the radioactive water leaking from two of its seven giant storage pits won’t end up in the Pacific Ocean, which Tepco has been polluting on and off for the past two years since the March 2011 quake and tsunami.
The Nuclear Regulation Authority summoned Tepco Executive Vice President Zengo Aizawa the same day over the leaking pools.
NRA Commissioner Toyoshi Fuketa said at a press conference after speaking with Aizawa that he is taking the release seriously but denied that it posed an immediate risk.
“It will take quite a long time . . . until the contamination spreads outside the site,” he said. “So we have a certain amount of time to take measures to contain the contamination.”
On Saturday, Tepco announced that 120 tons of toxic water containing about 710 billion becquerels of radioactivity had escaped from pool No. 2 but didn’t say where it went or where it might be. The seven pits, less than a kilometer from the sea, are 60 meters long, 53 meters wide and 6 meters deep.
Tepco dug the underground pools to store some of the endless seawater being injected into the three damaged reactors to cool the melted fuel rods. The rods must remain submerged even when the plant is not operating.
The most prevalent material being washed out with the water is cesium, which is being removed before the water is routed to the tanks. But other dangerous radioactive substances, such as strontium and tritium, can’t be removed yet and pose a hazard.
As a countermeasure, Tepco plans to empty the two tanks in question and transfer the water to other underground cisterns. The transfer from pool No. 2 began Saturday and is scheduled to end by Friday, Tepco spokesman Masayuki Ono said later in the day. The leak in pool No. 3 was confirmed as a small one on Sunday night.
Ono said that 15,200 tons of tainted water is expected to be removed from the two pits.
Before the pit leaks, a power outage blamed on a rat that short-circuited a power switchboard disabled the cooling systems for the spent-fuel pools of reactors 1, 3 and 4 in March.
The cooling system for the spent-fuel pool of reactor No. 3 was also halted for about three hours last week so workers could protect electrical equipment from small animals.
In the meantime, Kiyoshi Kurokawa, who led one of the panels that investigated the Fukushima crisis, said the situation has “clearly yet to be settled.”
Kurokawa made the remarks after being summoned to give unsworn testimony to a special new committee set up by the Diet to oversee the government’s handling of nuclear power issues and conduct investigations. Other members of the panel also testified.
The Diet-appointed panel said in its report last July that the failure of Tepco and Japan’s nuclear regulators to bolster the plant’s safety were caused by cozy business ties and declared that Fukushima was “clearly a man-made disaster.”
The panel members said Monday that oversight of the crippled plant’s operator remains too lax and that the NRA is only rubber-stamping Tepco’s work at the plant, which is still running on makeshift equipment.
Nine of the 10 members testified at the Lower House nuclear committee, speaking for the first time since releasing their findings in July.
Information from AP added.