  Establish cause of accident at Mihama nuclear power plant and inspect all nuclear power plants -- Akahata editorial, August 11 Four workers were killed and seven others injured on August 9 in an accident at the Kansai Electric Power CO. (KEPCO) Mihama Nuclear Power Plant in Fukui Prefecture. The fatal accident occurred when the cooling pipe carrying boiling water and superheated steam burst inside a turbine building of the No. 3 reactor. This is the severest nuclear power plant accident with the heaviest casualties ever in Japan. The accident raises questions whether KEPCO and the state had fulfilled their responsibility to secure the safety. Worst N-power accident in Japan Thorough investigation into the cause of the accident must come first. KEPCO cites the possibility that the pipes had weakened due to corrosion and wear. Following a similar accident in 1986, killing 4 workers at the Surry nuclear power plant in the United States, administration of nuclear power plants in Japan are said to have voluntarily inspected pipes to detect such flaws. However, KEPCO had not registered the broken pipes as inspection items for the administrative system and no checkup has ever been made on them. In April 2003, a subcontractor pointed out that the pipes were missing from the check list, but KEPCO did not take necessary steps. It also came to light that at KEPCO's Oi Nuclear Power Plant, coolant pipes in the secondary cooling system for the No. 1 reactor were found to be substandard in thickness but that KEPCO neglected to report the flaw to the state. The secondary cooling system is not required by law to be included in the regular inspection list because it does not directly lead to radioactive leaks. A Japanese Communist Party Dietmembers' team which visited the site of the accident found that there are no safety regulations concerning entry into the turbine facility at nuclear reactors in operation. The question is whether nuclear power plant safety can be assured by depending on a private company. Although no radioactive leak has been confirmed on the pipes for the secondary cooling system in the recent accident, any accident at a nuclear power generation plant must not be treated lightly. The nuclear reactor that caused the accident is 28 years old. Similar accidents could happen in the overaged reactor's pipes running the primary coolant to cool reactor core's fuel. It could reach the core of the No.3 reactor. Accidents concerning pipes of nuclear reactors are not rare. In Mihama, thin steel pipes for generating steam erupted at its No. 2 plant (pressurized water type) in February 2001, and primary coolant leaked at its No.3 plant in November 2002. Also, in November 2001, pipes burst at the Chubu Electric Power Co. Hamaoka No.1 plant (boiling water type). Irrespective of type, pressurized or boiling, a nuclear power plant has a number of pipes. They are partly eroded, worn down, and weakened due to high-temperatures and high-pressurized water and steam, as well as radiation. Japan has 20 nuclear power plants in operation since the 1970s, including the Mihama plant. An overall check must be comprehensively carried out without delay on these overaged plants as well as the rest of the plants in Japan. Establish safety-first nuclear power administration Public anxiety about and distrust of the government's nuclear power policy are rising. In 1999, a nuclear criticality accident occurred at the JCO nuclear fuel reprocessing plant, taking a toll of lives for the first time in Japan's nuclear power history and injuring near-by residents. In 2002, Tokyo Electric Power Co. concealed damage at nuclear power plants, followed by this year's revelation of concealed result of their assessment of costs for direct disposal of spent nuclear fuel by the state and a related firm. Ignoring residents' anxiety and opposition, the government is pushing ahead with the pluthermal plan that will increase the danger of accidents at nuclear power plants. Such a nuclear power policy should not continue any further. The Japanese Communist Party will make every effort to establish a safety-first nuclear power administration by eliminating the so-called "safety-myth" of nuclear power plants. (end) |