Tokyo: Mistaken radiation readings given out by the operator of Japan`s crippled nuclear plant were "absolutely unforgivable”, the government`s chief spokesman said on Monday, as work to prevent a catastrophic meltdown faced fresh hurdles.
Engineers have been battling to control the six-reactor Fukushima complex since it was damaged by a March 11 earthquake and tsunami that also left more than 27,000 people dead or missing across Japan`s devastated northeast.
Fires, explosions, and radiation leaks have repeatedly forced them to suspend work, including on Sunday when radiation levels spiked to 100,000 times above normal. Tokyo Electric Power Co, the plant operator, had earlier said it was 10 million times the normal.
"On one hand, I do think the workers at the site are getting quite tired," Chief Cabinet Secretary Yukio Edano told a news conference. "But these radiation tests are being used for making various decisions on safety and therefore these mistakes are absolutely unforgivable."
A partial meltdown of fuel rods inside the reactor vessel was responsible for the high levels of radiation at reactor No 2, Edano said.
"The airborne radiation is mainly contained within the reactor building. We must make sure this water does not seep out into the soil or out to sea," Edano said.
The spike in radiation levels forced a suspension of work over the weekend at the reactor, with experts warning that Japan faced a long fight to contain the world`s most dangerous atomic crisis in 25 years.
"This is far beyond what one nation can handle - it needs to be bumped up to the UN Security Council," said Najmedin Meshkati, of the University of Southern California. "In my humble opinion, this is more important than the Libya no-fly zone."
Tokyo Electric has conceded it faces a protracted and uncertain operation to contain the overheating fuel rods and avert a meltdown.
"Regrettably, we don`t have a concrete schedule at the moment to enable us to say in how many months or years (the crisis will be over)," TEPCO vice-president Sakae Muto said in the latest of round-the-clock briefings the company holds.
He also apologised over the mistaken radiation reading.
Sea radiation drops sharply
Radiation at the nuclear plant has soared in recent days, with a reading on Sunday showing contamination 100,000 times normal in water at reactor No 2.
But radiation levels in the nearby sea, which had soared on Sunday to 1,850 times normal, had come down sharply, Hidehiko Nishiyama, deputy director general of the Nuclear and Industrial Safety Agency, told a news conference on Monday.
Though experts said radiation in the Pacific waters will quickly dissipate, the levels at the site are clearly dangerous, and the 450 or so engineers there have won admiration and sympathy around the world for their bravery and sense of duty.
Last week, two workers at Fukushima were injured with radiation burns to their legs after water seeped over their shoes, and on Sunday engineers had to abandon reactor No 2 after the new reading.
Beyond the evacuation zone around Fukushima, traces of radiation have turned up in tap water in Tokyo 240 km (150 miles) to the south and even in rainwater samples in Massachusetts.
Japanese officials and international nuclear experts have generally said the levels away from the plant are not dangerous for humans, who anyway face higher radiation doses on a daily basis from natural substances, X-rays or plane flights.
In downtown Tokyo, a reading on Monday morning showed ambient radiation of 0.20 microsieverts per hour, well within the global average of naturally occurring background radiation of 0.17-0.39 microsieverts per hour. In Yamagata, a town about 110 km (70 miles) northwest of the stricken plant, the reading was just 0.15.
Two of the complex`s six reactors are now seen as safe but the other four are volatile, sometimes emitting steam and smoke.
Experts are anxious to find out whether the reactor cores are broken and leaking, as that could lead to a meltdown.
One long-term solution may be to entomb the Fukushima reactors in sand and concrete as happened at Chernobyl, Ukraine, after the 1986 disaster that was the world`s worst.
The Japan crisis has prompted a reassessment of nuclear power across the world. It had its most direct political impact yet in foreign politics in Germany at the weekend.
Chancellor Angela Merkel`s Christian Democrats lost control of Germany`s most prosperous state, Baden-Wuerttemberg, as anti-nuclear sentiment benefited her opponents in a regional vote.
Japanese Prime Minister Naoto Kan has kept a low profile during the crisis, but may face awkward questions after Kyodo news agency said his visit to the region the day after the disaster delayed TEPCO`s response to the unfolding situation.
The nuclear crisis has compounded Japan`s agony after the magnitude 9.0 quake and massive tsunami devastated its northeast coast, turning whole towns into apocalyptic-looking landscapes of mud and debris.
Residents there have been repeatedly rattled by aftershocks from the strongest earthquake in Japanese history, including a magnitude 6.5 tremor on Monday that triggered a tsunami warning.
The latest death toll was 10,804 people, with 16,244 still missing 17 days after the disaster. About a quarter of a million people are living in shelters.
Damage could top USD 300 billion, making it the world`s costliest natural disaster.
A Japanese scientist said if Japan had spent more on infrastructure it could have lessened the tsunami`s impact, but has become too reliant on low-cost measures such as handing out warning maps.
Japan should invoke Western-style urban planning to keep houses and hospitals further from the coast as it rebuilds from the crippling disaster, said Fumihiko Imamura, a professor at Tohoku University`s Disaster Control Research Centre.
Japan`s cash-strapped government has moved away in recent years from costly projects such as increasing the height of sea walls to budget measures like producing maps that show which areas are at lower sea levels, he said.
"We cooperate with the government on tsunami counter-measures, but there has been less financing and sometimes there isn`t enough for the construction of structural measures," Imamura said in an interview on Sunday.
"Now, the government`s focus has shifted to non-structural measures, because they are cheaper."