Historical Progress of Nuclear Safety Regulation in Japan
The First Period (1957–1978)
We can classify as the first period the two decades from 1957, when Japan established the Law for the Regulation of Nuclear Source Material, Nuclear Fuel Material and Reactors (the Nuclear Reactors Regulation Law), to 1978, when this Law was revised.
During this period, the Prime Minister had authority to approve licenses for nuclear businesses. Actually, the Director-General of the Science and Technology Agency, who was a cabinet member, had regulatory authority through assistance to the Prime Minister. As for commercial nuclear power reactors and commercial marine reactors, however, administrative measures, including construction permits issued by the Prime Minister, required the consent of the competent ministers (Article 71 of the Nuclear Reactors Regulation Law). In this case these were the Minister of International Trade and Industry (MITI) and the Minister of Transport, because these reactors had already been regulated by the old Electricity Business Act and the Ship Safety Act. In addition, some regulatory approvals and inspections of these two types of reactors, including approvals of design and construction plan, inspections of facilities and their performance, pre-service inspections, and periodic inspections, were exempted from the application of the Nuclear Reactors Regulation Law and were left to be covered by existing regulations (Article 73).
Meanwhile, the Nuclear Reactors Regulation Law also stipulated that the Prime Minister should listen to and respect the opinion of the Atomic Energy Commission of Japan (JAEC), which was established under the Prime Minister's Office based on Article 8 of the National Government Organization Act, including matters concerning safety regulation (Paragraph 2, Article 4). The DirectorGeneral of the Science and Technology Agency took on the position of chair person of the JAEC and this agency dealt with the staff work of the Commission. There had been controversy as to whether the JAEC should be set up as an organization prescribed in Article 3 or Article 8 of the National Government Organization Act, as the former is a decision-making organ and the latter is an advisory one. In the end, the JAEC was established as a de facto decision-making organ despite its legal nature as a very strong advisory council .
In this first period, one administrative agency—legally the Prime Minister, but actually the Science and Technology Agency—had nearly exclusively implemented nuclear safety regulation, even though some approvals were required by relevant ministries. Additionally, the JAEC had been established as a highly independent advisory council whose members were appointed upon confirmation from both Houses of the Diet. It was thought that the reason the JAEC had been granted a great deal of independence was so that it could ensure peaceful use of nuclear energy, as the purpose of its establishment was to provide “democratic administration of public affairs” (Article 4 of the Atomic Energy Basic Law and Article 1 of the Act for Establishment of the Atomic Energy Commission).
The Second Period (1978–1999)
The 1974 radiation leakage accident of Mutsu, the first and the only nuclearpowered ship in Japan, aroused public mistrust in the Japanese nuclear administration as a whole. The Japanese government established the Advisory Committee on Atomic Energy Administration under the Prime Minister in February 1975, whose chairman was Hiromi Arisawa, Emeritus Professor of the University of Tokyo, to reexamine the institution of nuclear-related organizations. Based on the Committee's report, the Nuclear Reactors Regulation Law was revised in 1978. We can regard as the second period the twenty years from that time to 1999 when the JCO criticality accident occurred, and the nuclear regulatory institution was reformed as a result of the reorganization of the central government.
The Arisawa Advisory Committee submitted its report in July 1976 detailing its recommendations on the reform and enhancement of nuclear administration in Japan. Three assertions closely linked with nuclear safety regulation were pointed out in this report as follows:
• To separate the functions related to nuclear safety from those of the JAEC, and to establish a new committee which shall deal with nuclear safety and doublecheck the safety reviews by the administrative agencies for enhancing the institutional framework of securing nuclear safety;
• To implement safety regulations consistently according to the types of reactors to clarify the responsibility of administrative agencies for ensuring the safety of nuclear reactors—the Minister of MITI be responsible for the regulation of commercial nuclear power reactors, the Minister of Transport for those of commercial marine reactors, and the Prime Minister for those of research and test reactors and those in the stage of research and development; and
• To implement some government measures such as holding public hearings and
symposia to dispel the public's concerns over nuclear safety and obtain the public's understanding and cooperation on nuclear energy development .
Based on these recommendations, the Nuclear Reactors Regulation Law was revised in 1978 as described below. First, this revision assured consistency of safety regulations with respect to each type of reactor for ensuring their safety as follows: commercial nuclear power reactors would be regulated by the Minister of MITI, commercial marine reactors by the Minister of Transport, and research and test reactors and those in the stage of research and development by the Prime Minister. Next, the functions relevant to safety were separated from the JAEC and the Nuclear Safety Commission of Japan (NSC) was newly established to exercise jurisdiction over nuclear safety issues. Still, the legal position of the NSC fell under the category of “Councils, etc.” prescribed in Article 8 of the National Administrative Organization Act as did that of the JAEC. As a result of this reform, the competent ministers were required to listen to and respect the opinions of the NSC about safety-related issues when they designated activities and issued permits; and the NSC stated its opinion in the form of double-checking safety reviews of the competent ministers on nuclear regulation. Meanwhile, neither the NSC nor the JAEC had its own secretariat, so the Science and Technology Agency dealt with the staff work of both Commissions.
With regard to the institutional form of the NSC and that of the JAEC whose reform was also re-examined at that time, the controversy as to whether an Article 3 organ or an Article 8 organ was adequate was rekindled. The Arisawa Committee concluded that the NSC and the JAEC should be “advisory committees” although the Socialist Party of Japan, the Japanese Communist Party, and the Federation of Electric Power Related Industry Workers' Unions of Japan proposed changing these institutional forms to “administrative committees” which have executive authority, such as the Japan Fair Trade Commission. The Arisawa Committee provided two reasons to support its conclusion as follows:
• Under the form of administrative committee, the JAEC and the NSC could not sufficiently perform their role as “the guardian of the Atomic Energy Basic Law” and would lose their ability to monitor the government because to become administrative committees meant being part of the government.
• The primary need was to secure the autonomy of both committees from the
government from the viewpoint of ensuring the peaceful use of nuclear energy which was the starting point for Japan's nuclear energy development .
In addition to these considerations, the problem of the scope of authority was taken into account. That is, administrative committees could not deal with any issues other than their own administrative affairs authorized clearly by law. That meant there was the possibility that they would not be able to cover all the safetyrelated issues unless the laws prescribed the scope of authority very broadly; and that making a broad stipulation could overlap with the authority of other governmental agencies .
Furthermore, two public hearings would need to be held during the siting process of nuclear power plants (NPPs). Primary public hearings were held by MITI concerning various issues related to construction of NPPs before the Electric Power Development Coordination Council (so-called “Den-Chō-Shin”) decided the Electric Power Development Master Plan for building new commercial nuclear power reactors. And secondary public hearings would be held by the NSC on the occasion of double-checking safety review documents submitted by MITI .
In this second period, the regulatory authorities were decentralized. What is more, several governmental agencies, including the ministries which had held jurisdiction over the development and promotion of nuclear businesses, also regulated nuclear safety according to the types of business. This was because the centralized regime of safety regulation in the first period had been judged not to work adequately. However, it can be said that these changes strengthened the integration inside each type of business, which meant the level of integration between the promotion side and the regulation side was enhanced. In addition, the highly independent advisory committee became responsible for the preliminary review of regulation by the regulatory agencies.