TOKYO (Reuters) - Japan unveiled new plans on Tuesday to contain the crisis at a crippled nuclear plant after admitting it faced greater challenges than first disclosed, but it kept to a goal of bringing the reactors under control by January.
More than two months after a 9.0 magnitude earthquake and a deadly tsunami set off the worst nuclear disaster since Chernobyl, officials say the risk of another explosion at the Fukushima plant has receded but each step toward gaining control has been matched by new setbacks.
The crisis has also prompted a blank-slate review of Japan’s national energy policy, which had included a goal of generating half of the nation’s power from nuclear plants by 2030.
From the start, the timetable for stabilizing Fukushima, announced just over a month ago, has faced skepticism from experts and the Japanese public, but any changes in the original target were seen as too costly politically for the government.
Tokyo Electric Power Co, the plant’s operator, said it had dropped an initial plan to flood the reactors with water after last week’s discovery of a large leak in the main vessel of the plant’s No. 1 reactor.
Instead, the embattled utility said it would now try to cool the reactors by circulating the radioactive water that has pooled throughout the Fukushima complex. Most of the water is within the reactor buildings but some is outside in trenches.
The new approach will involve costly steps to decontaminate tens of thousands of tons water and the construction of a large storage area for the remaining low-level waste.
In a move that acknowledged a risk that it had previously downplayed, Tokyo Electric said it would step up its monitoring of radiation in nearby seawater and attempt to build a kind of underground fence to prevent groundwater contamination.
The utility, also known as Tepco, said it still aimed to complete initial steps to limit the release of further radiation from the plant 240 km (150 miles) northeast of Tokyo and to shut down its three unstable reactors by January 2012.
“We know that there are a lot of defining factors and risks, but we still want to complete the first steps by July and the remainder of the plan within nine months,” Sakae Muto, a Tepco vice president said at a news conference.
He added it was impossible to estimate how much the clean-up of Fukushima, which has six reactors in total, would cost. “It’s something we will have to study over time.”
Aware of growing public frustration over the protracted crisis, Prime Minister Naoto Kan said that the government would support those who had been displaced and lost work because of the nuclear crisis.
That included aiming to start paying out compensation by late July for a crisis that has displaced some 80,000 people. Outside analysts have said the final cost for compensation for the damage caused by the crisis could range up to $130 billion.
The government said it would build 15,200 temporary housing units by mid-August for those who have evacuated from the plant’s vicinity and step up health monitoring for nearby residents and workers.
“Japan must deal head-on with the feeling of betrayal that the people who lived near the plant are experiencing, having long shown understanding for Japan’s nuclear power policy believing that it was safe,” Kaieda told a news conference.
Kan’s government has been under fire for its response to the quake and tsunami, which left almost 25,000 dead or missing, and 116,000 still without homes.
Tepco has also drawn ire for downplaying the severity of the situation. The utility said only this week that it believed three of the reactors had suffered a meltdown, where the fuel rods at the core of the reactor melted, leading to a larger release of radiation.
Still, in an endorsement of Japan’s efforts, the U.S. State Department revised its travel advisory, saying it was the “unanimous opinion” of American experts that it was now safe to travel through the Fukushima evacuation zone by train and on a major highway.
“While the situation remains serious, and there is still a possibility of unanticipated developments, cooling efforts are ongoing and successful, power, water supply, and back-up services have been partially or fully restored, and planning has begun to control radioactive contamination and mitigate future dangers,” it said Monday.
The updated plan sketched out the new methods which would in particular focus on how to clean up the large amount of water contaminated by radiation.
The aim is to bring the reactors to a state of “cold shutdown,” where the uranium at the core is no longer capable of boiling off the water used as a coolant. That would allow officials to move on to cleaning up the site and eventually removing the fuel from the site, a process that could take more than a decade.
New details about the state of the plant released in the past week by its operator have made it clear that the reactors suffered far more serious damage than previously disclosed.
Fuel rods in three reactors - Nos. 1, 2 and 3 - were uncovered for between six to 14 hours after the quake. They heated up rapidly and went into an uncontrolled meltdown, officials now say.
Because of the damage from the quake, a series of hydrogen explosions and the core meltdowns, the reactors are leaking most of the water being pumped in to keep them cool. The resulting growing pool of radioactive water at the site — enough to fill 36 Olympic-sized polls — is now the major focus of the revised plan of attack.
Radiation levels around the plant have dropped sharply from the levels recorded in March but remain elevated. At Fukushima’s west gate, for instance, the radiation dose per hour is more than five times the natural background dose per year in the United States.
Other areas of the plant remain more dangerous. A robot inside the No. 1 reactor last week recorded a reading of 2,000 millisieverts per hour. A 30-minute exposure at that rate would be high enough to cause symptoms of radiation sickness including nausea and a drop in white blood cell count.
Meanwhile, farmers south of Tokyo in Kanagawa have been forced to destroy an early tea crop because of risky levels of cesium.
Last week, government workers began to kill an estimated 1,500 cows and pigs in the 20-km (12-mile) “no-go” zone around Fukushima. Burning the bodies could spread radiation, so they are being covered with blue tarps and lime and left to decay, officials say.
Reporting by Kiyoshi Takenaka and Shinichi Saoshiro, additional reporting by Mari Saito, writing by Kevin Krolicki and Tomasz Janowski; Editing by Alex Richardson