from NUKE INFO TOKYO 69 (Jan./Feb. 1999)
— 15,000 Drums Containing Low-level Radioactive Waste Found Corroded
— Compensation for Damages Caused by Nuclear Plant Accidents Raised to ¥60 Billion
— Study Underway to Plan for a MOX Fabrication Plant
— Safety Regulations to be Centralized in Ministry of Economy and Industry Clearance Levels Proposed
— HTTR Went Critical
15,000 Drums Containing Low-level Radioactive Waste Found Corroded
Of about 500,000 drums containing low-level radioactive waste stored at nuclear plant sites throughout Japan, about 15,000 have been found corroded. For those that have holes, stainless plates have been attached to mend them.
Power companies had not made this information public, claiming that they did not find any safety problems. However, it was revealed on November 24 by Japan Nuclear Fuel Limited – in charge of handling drums at the burial facility in Rokkasho, Aomori Prefecture – that 1,208 drums out of a total of 2,472 scheduled to be transported to the facility in January 1999 from Tokyo Electric Power Co’s Fukushima I had been mended. It was only then that the overall figures for mended drums was disclosed following investigations conducted by the Federation of Electric Power Companies.
Compensation for Damages Caused by Nuclear Plant Accidents Raised to ¥60 Billion
In a report compiled on December 11, 1998 by the Atomic Energy Commission’s special committee on nuclear damage compensation system, it was noted that the amount that power companies reserve for compensating damages caused by nuclear accidents would be doubled to ¥60 billion from the current amount, ¥30 billion.
Based on the report, the Science and Technology Agency at the next regular meeting of the Diet will propose amendments to relevant laws.
The power companies have unlimited liabilities for compensating damages caused by nuclear accidents (excluding those caused by tremendous natural disasters or social upheavals). But the amount they have to reserve has been stipulated by law and a contract of appropriate insurance has been made. In case the actual compensation exceeds this amount, the government is supposed to provide necessary subsidiary payments and low-interest loans based on a resolution of the National Diet.
Study Underway to Plan for a MOX Fabrication Plant
Japan Nuclear Fuel Ltd. (JNFL) announced on December 21 that it would begin a study commissioned by the Federation of Electric Power Companies in early 1999 designed to look into how best to establish the MOX fuel fabrication business. JNFL explains that it was only commissioned to investigate conditions for building plants in Japan, and that neither sites nor responsible oversight bodies will be specified. However, as JNFL has been constructing a reprocessing plant in Rokkasho, Aomori Prefecture, it is generally believed that a MOX fabrication plant will be built in the area adjacent to the reprocessing plant in order to avoid transporting plutonium. This commissioned research can be seen as the first step towards choosing Rokkasho as a possible site for the plant.
Safety Regulations to be Centralized in Ministry of Economy and Industry
The Science and Technology Agency Director-General, Mr. Takeyama and Minister of International Trade and Industry, Mr.Yosano conducted talks on November 17-18 for almost five hours regarding reorganization of government offices scheduled to take place in 2001. The talks addressed questions about how administration of nuclear power should be divided between the two Ministries and what new arrangements must be established to involve the Ministry of Education, Science and Technology and the Ministry of Economy and Industry. As a result of the talks, the Ministry of Economy and Industry will be given sole responsibility for safety regulations. The exception will be safety regulations for nuclear fuel material handled for experimental and research purposes that will be under the regulatory supervision of the Ministry of Education, Science and Technology. The Nuclear Safety Commission will continue to double-check safety procedures.
It was also decided that the Japan Nuclear Cycle Development Institute (formerly PNC) will be jointly administered by the two Ministries. The Ministry of Education, Science and Technology will be in charge of research and development at Monju, whereas the Ministry of Economy and Industry will be in charge of high-level radioactive waste disposal.
Clearance Levels Proposed
The Nuclear Safety Commission’s radioactive waste safety standards special committee compiled on December 15 a draft report proposing so-called “clearance levels” which allow utilities to separate concrete and metal from waste materials produced at decommissioned reactors as “not radioactive”. NSC has been asking the public to submit their opinions on the proposal for one month.
In the draft, 0.01 milli-Sv/year has been taken as a standard figure at which exposure risks can be ignored, and they calculated the level of radioactivity for 20 major radionuclides, which will not exceed the standard figure when wastes are disposed underground or even recycled. Most of these figures are about the same as those mentioned in the IAEA’s technical document (January 1996), but some are more severe and others are more relaxed. This shows how unreliable the consistency is between radioactive levels and exposure doses that are proposed by the Nuclear Safety Commission. Not only people involved in the anti-nuclear movement but also citizens involved in the consumer movement and those opposing newly-planned industrial waste sites have begun to protest such “clearance levels.” People who are protesting state that it is not acceptable to dump nuclear waste mixed with other non-radioactive waste or to have it reused in some daily products, no matter what level the radioactivity might be.
HTTR Went Critical
The High Temperature Gas-cooled Reactor (HTTR), which the Japan Atomic Energy Research Institute constructed in Oarai-machi, Ibaraki Prefecture achieved criticality on November 11. But there are many remaining technical problems that must be overcome before the reactor can be used for practical purposes, and industries have little interest in utilizing heat from the reactor.
According to the initial plan the reactor was scheduled to go critical at the end of 1997, but plans were delayed to June, September and finally to November 1998. A number of troubles occurred: in the experiment with “low temperature” using mock fuel, some equipment and shielding concrete were heated beyond temperature limits and control rods moved in the opposite direction from where they were instructed to go. It was found after loading fuel that the assumed amount of fuel necessary for achieving criticality was wrongly estimated.
The full loading of fuel was completed on December 16. It is planned to achieve a thermal output of 10 MW in September 1999 and by June 2000 will reach its full output of 30 MW. Some people believe, however, that the reactor will never achieve full output due to various defects including an inability to remove impurities in coolant helium gas.