Disassembly of N-reactors a joint effort? / Toshiba seeks cooperation of rival Hitachi
Toshiba Corp. has proposed to rival Hitachi, Ltd. that the two companies join hands in decommissioning the crippled reactors at the Fukushima No. 1 nuclear power plant in Fukushima Prefecture, The Yomiuri Shimbun learned Wednesday.Toshiba and Hitachi, manufacturers of some of the reactors at the plant operated by Tokyo Electric Power Co., had separately proposed their own decommissioning plans, including task lists and timetables.
But Toshiba has hinted that it would revise its decommissioning plan into one to be carried out jointly with Hitachi. A top Toshiba official said, "We're calling on [the Hitachi side] to work with us, as we will be working on the same site at the Fukushima No. 1 nuclear plant."
Of the six nuclear reactors at the Fukushima No. 1 nuclear plant, the Nos. 1 to 4 reactors need to be decommissioned. It is the first time in the world for four reactors to face such severe trouble simultaneously.
The No. 1 reactor was manufactured by General Electric Co., the No. 2 by GE and Toshiba, the No. 3 by Toshiba and the No. 4 by Hitachi.
Toshiba has called for Hitachi to decommission the reactors jointly, as the difficult task may face rough going in the aftermath of hydrogen explosions that occurred at the Nos. 1 and 3 reactors.
Hitachi has reportedly shown a positive stance on a joint decommissioning project with Toshiba. Even if the plan is realized, the work will take at least 10 years.
On April 4, Toshiba made a proposal on decommissioning to TEPCO, jointly with four U.S. companies, including its subsidiary Westinghouse Electric Co. Under that plan, the decommissioning work would be completed in about 10 years at the earliest.
Specifically, the work of cooling the interior of the overheated reactors and removing debris would be done in the next six months, while the following five years would be spent on removing fuel rods from the reactor and spent fuel rods from a storage pool. In the final five years, the buildings housing the reactors and other equipment would be dismantled, along with the reactors themselves, while the contaminated ground would undergo soil improvement and the whole lot would be left vacant.
Meanwhile, Hitachi has formed a 30-member team of experts, jointly with six other firms, including GE and leading U.S. industrial plant manufacturer Bechtel Corp.
The plan proposed by the Hitachi team includes the work of taking nuclear fuel out of the reactor, the decontamination of equipment and of buildings housing reactors and other machinery, the dismantling of the buildings and the disposal of waste following the dismantling. Under this plan, the entire task would take about 30 years.
The Hitachi plan is based on their experience of analogous work in the aftermath of the Three Mile Island nuclear plant accident in the United States and the Chernobyl nuclear plant accident in Ukraine, then a Soviet republic.
Govt may have other utilities share TEPCO's compensation burden
The government is considering a plan to form a mutual aid system that would include Tokyo Electric Power Co. and all other power companies in the nation to pay compensation to people who suffered from the nuclear accident at the Fukushima No. 1 nuclear power plant, it has been learned.
The mutual aid system is modeled after the compensation program established for damage caused by the 1979 nuclear accident at the Three Mile Island nuclear power station in the United States.
According to the government's draft plan, each power company might be assessed 30 billion yen to 50 billion yen for each of their nuclear reactors, though the actual amount could be negotiated later.
TEPCO, the operator of the crippled nuclear plant, would be required to pay as much as 2 trillion yen to 3.8 trillion yen in total, including its contribution to the system plus other obligations.
Compensation in excess of the total amount borne by the power companies would be fully covered by the government, according to the draft plan.
The government is considering the creation of a special law to establish the compensation program, sources said. The government and TEPCO will soon start talks over how to pay for the damages.
According to the draft plan, TEPCO would pay 100 billion yen to 200 billion yen every year from its annual profit for 15 years to pay for damages. In addition, it would pay 510 billion yen to 850 billion yen for the mutual aid program, representing the charge assessed for its 17 nuclear reactors.
The other power companies own a total of 37 nuclear reactors around Japan. Each company will pay a charge based on the number of nuclear reactors it owns. The total charges borne by the nation's nine power companies would be 1.1 trillion yen to 1.8 trillion yen.
The government will shoulder up to 240 billion yen based on the Law on Compensation for Nuclear Damages. In addition, if the total compensation required exceeds the amount shouldered by the utilities, the excess would be fully covered by the government, according to the draft plan.
However, power companies not related to the crippled Fukushima plant are likely to protest strongly if they are required to share the compensation burden with TEPCO.
Child-rearing benefits face ax / Handouts to be abolished to free up funds for quake reconstruction
The government and the ruling Democratic Party of Japan are set to abolish the child-rearing allowance system in October, which could free up some of the huge funds needed for earthquake disaster reconstruction efforts, according to sources.The current stopgap legislation maintains the payment of 13,000 yen per month for each child through September. The government and the DPJ have begun coordinating on legislative moves to abolish the system when the period expires, having judged it would be difficult to secure fiscal resources to finance the allowances after last month's Great East Japan Earthquake, the sources said.
Child benefits, however, would continue based on the previous system of dependent child allowances with income caps, introduced during the administration of the Liberal Democratic Party and its coalition partner New Komeito, with some modifications, according to the sources.
The DPJ-led administration, which came to power in 2009, introduced the child-rearing allowance system in 2010 under a law enacted as temporary legislation effective for fiscal 2010.
For this fiscal year, the government submitted a bill to the current Diet session to raise the amount of payments for households with children under 3 years old to 20,000 yen per month. But it gave up on efforts to enact the legislation due to resistance from the opposition camp.
With support from the opposition Japanese Communist Party and the Social Democratic Party, the government passed the stopgap legislation to keep the same level of payments from last fiscal year through September.
However, the government and the DPJ have decided to give priority to disaster reconstruction funding. Continuing the current payment system after September would cost about 1.1 trillion yen, the sources said.
If and when the current child allowance system is abolished or allowed to expire, the previous system of income-capped dependent child allowances, based on a permanent law, would automatically be reinstated.
Komeito, which wants the previous system revived, has proposed modifying the system, such as uniformly setting payments at 10,000 yen per month and imposing no income caps on residents in disaster-hit areas. Under the previous system, the payments were 5,000 yen or 10,000 yen per child depending on certain conditions regarding the age and number of children targeted. The Komeito proposal is expected to cost about 600 billion yen.
The government and the DPJ are considering using the Komeito proposal as a basis and allocating the other 500 billion yen in a second supplementary budget for this fiscal year, which is expected to be devoted exclusively to disaster reconstruction measures.
Some DPJ executive board members are even calling for a shift to the previous system before October, to curb the issuance of deficit-covering government bonds in the envisaged second extra budget.
One crisis after another harried TEPCO's response
This is the third installment in a series focusing on delays in implementing emergency steps by the government and Tokyo Electric Power Co. to deal with the unprecedented nuclear crisis at the Fukushima No. 1 nuclear power plant.TEPCO's venting of radioactive steam from a reactor at the crippled Fukushima No. 1 nuclear plant came too late, but even after the utility acted, a series of hydrogen explosions at the plant's reactor buildings quickly turned the situation into a nightmare the government's Nuclear and Industrial Safety Agency had never anticipated.
Under ordinary circumstances, reactor containment vessels that cover pressure vessels contain nearly no oxygen, making it almost impossible for the substance to chemically react with hydrogen and set off a blast. Even if hydrogen is generated in a reactor, it should not leak from the containment vessel. But after the disaster damaged pipe joints in the reactor building, hydrogen from inside the reactor leaked into the outer structure.
The first blast occurred at the No. 1 reactor at 3:36 p.m. on March 12, about five hours after the radioactive steam was released. The event violently shook an earthquake-resistant building nearby that was housing the crisis headquarters in the compound.
An employee of a TEPCO partner company said he was sitting on the floor when the explosion hit and it tossed him about 10 centimeters up in the air. "I thought an earthquake had hit nearby," he said. People around him started shouting, "Check the [radiation] dose!"
TEPCO officials at the crisis headquarters became seriously alarmed. They feared another explosion could rock the No. 3 reactor.
On the night of March 12, workers from the headquarters tried to lay power cable from No. 4 reactor's turbine building to the No. 3 reactor's cooling motor, hoping No. 4's power supply was still functioning. But the door to the turbine building had been warped by the tsunami and was stuck shut. It took the workers about three hours to remove the door, but they soon saw their work had been for nothing. The No. 4 reactor's power supply was dead.
Slowly, workers at the power station were realizing the tsunami had caused destruction beyond their imagination.
At 11 a.m. on March 14, the No. 3 reactor building exploded and again the headquarters in the quake-resistant structure was given a violent shake.
These two explosions--on March 12 and 14--underlined the severity of the nuclear crisis for Defense Ministry officials in Tokyo.
After the blast at the No. 1 reactor on March 12, the officials received a report from the nuclear safety agency saying, "The No. 2 reactor is unstable." But the only action TEPCO's crisis headquarters said it would take was to "respond to rising pressure [at the No. 3 reactor] by venting the reactor."
Even after the blast at No. 3 reactor, the nuclear safety agency continued to say the reactor vessel was sound and the container was filled with water.
At 6:10 a.m. on March 15, an explosion was heard from the No. 2 reactor. This was followed by a fire near a storage pool for spent nuclear fuel at the No. 4 reactor at 9:38 a.m. Radiation in excess of 400 milisieverts per hour was detected in the vicinity.
Until this point, the nuclear safety agency had been saying the No. 4 reactor was relatively stable. TEPCO had repeatedly said the No. 4 reactor had been stopped and as long as there was water in the spent fuel storage pool, things would be fine. The firm had been frantically trying to deal with the crises that kept erupting at the Nos. 1-3 reactors, like a deadly game of whack-a-mole.
It was starting to dawn on government officials, including Defense Minister Toshimi Kitazawa, that the nuclear safety agency and TEPCO lacked the ability to make appropriate decisions. They were becoming frustrated by what they saw as constant changes to explanations about what was happening at the power station. Distrust in the agency and TEPCO was soaring.
But TEPCO and the nuclear safety agency had their hands full responding to the volatile situation surrounding the No. 2 reactor after the blast at the No. 1 reactor. Dealing with one urgent crisis after another, they had no time to take actions that would have averted the more serious situation that was to develop.
The situation at the Fukushima complex had grown from simply out-of-hand into a disaster of unimaginable dimensions.
Scientists say aftershocks far from over
In the month since the March 11 earthquake, there have been frequent aftershocks at and around the initial quake's focus, including many strong quakes with a magnitude of 5 or higher. Experts say there are more shocks to come, possibly as strong as magnitude 8.The phenomena can be attributed to the enormous changes in the force exerted in the Earth's surface in the eastern part of the nation due to the Great East Japan Earthquake, which measured magnitude-9.0 on the open-ended Richter scale, according to seismologists.
On Tuesday, a magnitude-5.6 earthquake occurred in northern Nagano Prefecture, while on the same day a magnitude-6.4 earthquake struck offshore from eastern Chiba Prefecture. On Monday, a magnitude-7.0 earthquake took place in eastern Fukushima Prefecture.
The Metrological Agency warned, "Earthquakes have come to occur frequently as the geological dynamics of eastern Japan have changed due to the March 11 earthquake."
"We have to expect more earthquakes in the magnitude-7.0 class for the time being," it warned.
On March 12, northern Nagano was jolted by a magnitude-6.7 earthquake whose focus was 20 kilometers north of that of the Tuesday earthquake.
Among seismologists, the area was already known for ground distortion in many places. But the March 11 earthquake increased the pressure the ground there is subjected to. Earthquakes measuring 1 or higher on the Japanese seismic intensity scale of 7 have occurred at least 430 times in the region since March 12.
The apparent southern boundary of the aftershock zone from the March 11 earthquake is off the shore of eastern Chiba Prefecture. In that area, the Pacific plate and the Philippine Sea plate slide under the landward plate that includes eastern Japan. Tuesday's earthquake off Chiba occurred because faults in the landward plate became active.
Movements of the Philippine Sea plate affect seismic activity in Tokyo Bay. But only a few earthquakes at the magnitude-3 or magnitude-4 levels have been recorded there since March 11, according to the agency. The level of seismic activity has not changed much.
However, Prof. Koshun Yamaoka of Nagoya University pointed out that seismic activity in northern Chiba and southern Ibaraki Prefectures, which is also linked to the Philippine Sea plate, has increased.
"An earthquake could hit the Tokyo metropolitan area with its focus directly below the city. We'll have to observe the situation carefully," Yamaoka added.
The professor anticipates the rise in seismic activity in eastern Japan will continue for four or five years. He said magnitude-7 quakes "are likely to occur once or twice in the next month."
"After that, they can be expected to happen once in two months. The occurrence of such huge earthquakes will gradually decrease to once in a half year. But the possibility remains that a magnitude-8 earthquake could happen at any time," Yamaoka warned.
Yoshimitsu Okada, president of the National Research Institute for Earth Science and Disaster Prevention, said, "Aftershocks of the March 11 earthquake occurred in shallow places in the Earth's crust and triggered other aftershocks."
"The frequency of earthquakes has increased by aftershocks caused by aftershocks of the March 11 earthquake," Okada added.
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