3.2. Análisis de la situación
3.3.4. Actividades de animación a la lectura en general.
REQUIREMENTS GOVERNING THE SAFETY OF NUCLEAR POWER
STATIONS IN CANADA
At present, pending the coming into force of the new NSC Act, regulatory control over nuclear power stations in Canada comes primarily from the authority of these statutes and regulations:
• the AEC Act (see Attachment 7.1);
• regulations made pursuant to the AEC Act, for example:
÷ Atomic Energy Control Regulations (see Attachment 7.2) ÷ Physical Security Regulations (see Attachment 7.3) ÷ Transport Packaging of Radioactive Materials Regulations
(see Attachment 7.4)
÷ Cost Recovery Fees Regulations (see Attachment 7.5)
The last major revision to the AEC Regulations came into effect in June 1974. These regulations describe the general conditions and requirements for the licensing of prescribed substances and nuclear power stations. Further amendments have been issued since that date, but they do not relate to the licensing of nuclear power stations.
Legal requirements are imposed on licensees by the AEC Act, the regulations made pursuant to that Act, and the licence conditions which the regulations empower the AECB to include in specific licences. Contravention of the act, regulations, or binding licence conditions constitutes an offence under the Act. Sanctions for offences include prosecution and revocation, suspension or amendment of the licence by the AECB.
For nuclear power stations, the regulations require that:
• A licence to operate be acquired from the Board (s. 9), with a prerequisite of Board approval to construct or acquire the facility (s. 10).
• General prescribed requirements are met when applying for and obtaining a licence (s. 9).
• Records are kept and occurrences are reported (s. 11).
• Radiation exposures are kept below the limits are set out in Schedule II.
As with most other countries, the radiation protection regulations are based upon the recommendations of the International Commission on Radiological Protection.
7.2.1
The New Act
On March 20, 1997, Bill C-23, the NSC Act (see Attachment 7.7) received Royal Assent. The new Act will replace the current AEC Act with a modern statute to provide for more explicit and effective regulation of nuclear energy.
The existing Act encompasses both the regulatory and developmental aspects of nuclear activities. However, the new Act will disconnect the two functions and provide a distinct identity to the regulatory agency. The new Act will replace the AECB with the Canadian Nuclear Safety Commission (CNSC). It clearly defines the CNSC’s separate role from that of AECL, which is the federal research, development, and marketing organization for nuclear energy.
Since the AEC Act was first adopted in 1946, the mandate of the regulatory agency has evolved from one chiefly concerned with national security to one that focuses primarily on:
• health
• safety
• environmental consequences
The new Act will provide the CNSC with a mandate to establish and enforce national standards in these areas. It will also provide a more explicit basis for implementing Canadian policy and fulfilling Canada’s obligations about non-proliferation of nuclear weapons.
The new Act will:
• permit an increase in the number of members of the Commission from five to seven to provide a broader range of expertise and will permit them to sit in panels;
• make the Commission a court of record with powers to hear witnesses, take evidence and control its proceedings, and at the same time, maintaining its flexibility to hold informal hearings;
• set out a formal system for review and appeal of decisions and orders made by the Commission, designated officers and inspectors;
• empower the Commission to require financial guarantees, to order remedial action in hazardous situations and to require responsible parties to bear the costs of decontamination and other remedial measures;
• bring the enforcement powers of compliance inspectors and the penalties for infractions into line with current Canadian legislative practices;
• bind the Crown, both federal and provincial, and the private sector;
• provide authority to incorporate provincial laws by reference and to delegate powers to the provinces in areas better regulated by them or where licensees would otherwise be subject to overlapping regulatory provisions;
• explicitly provide for the recovery of the costs of regulation from persons licensed under the Act.
The new Act will come into force when a suitable set of new regulations has been prepared. The AECB has consulted widely with the public, interest groups, licensees, and other stakeholders on the development of the new regulations. The AECB expects to have the new legislation proclaimed and all supporting documentation, including regulations, in place by the end of 1998 or by early 1999.
7.2.2
Nuclear Liability Act
The other substantive legislation enacted by Parliament specifically about nuclear energy is the Nuclear Liability Act (see Attachment 7.6). This Act, which entered into force in October 1976, places total responsibility for nuclear damage on the operator of a nuclear installation. It requires the operator to carry insurance in the amount of $75 million. It also provides for the establishment of a Nuclear Damage Claims Commission. This commission will deal with claims for compensation when the federal government deems that a special tribunal is necessary; for example, if the claims are likely to exceed $75 million. The Act recognizes that Canada may enter into international arrangements that carry nuclear liability, but at present, Canada is not a party to any such arrangement.
7.2.3
Canadian Environmental Assessment Act (CEAA)
Before 1984, the AECB was not directly concerned with environmental protection during site preparation and construction of nuclear power stations. Instead, the AECB would maintain contact with the provincial agencies responsible for environmental protection. This allowed the provincial agencies to identify any environmental issues that needed to be resolved as a prerequisite to AECB’s approval. The AECB policy has been that it would not approve any site preparation or construction work until all these environmental issues were resolved.
In 1984, the federal government introduced an environmental review process that applied to proposals where:
• a federal government agency was the initiating department;
• there was an environmental effect on an area of federal responsibility; • the federal government had a financial commitment;
• the proposal made use of lands administered by the Government of Canada. Federal regulatory bodies such as the AECB were obliged to observe the process.
In 1995, this process was succeeded by the CEAA (see Attachment 7.8), which sets out responsibilities and procedures for the environmental assessment of projects involving the federal government. The Act applies to projects for which the federal government holds decision-making authority - whether as proponent, land
administrator, source of funding, or regulator.
The majority of federal projects requiring an environment assessment will undergo either a screening or a comprehensive study. Both can be considered self-directed environment assessments in the sense that the Responsible Authority (RA) determines the scope of the environment assessment and the scope of the factors to be considered, directly manages the environment assessment process, and ensures the environment assessment report is prepared. The RA is the federal decision maker having
responsibility under the Act. The AECB is a RA for projects that it regulates.
In practice, the project proponent may conduct the environment assessment, prepare the report, and design and implement mitigation measures and a follow-up program. The RA alone, however, remains directly responsible for ensuring that the screening or comprehensive study is carried out in compliance with the Act, and for deciding on the course of action with respect to the project following the screening or
comprehensive study.
The CEAA requires that early on in the project a proponent carry out an integrated environment assessment of the possible impact of all licensing stages, before any irrevocable decisions are made.
7.2.4
Regulatory Documents
In addition to the various legally binding regulations issued pursuant to the AEC Act, the AECB issues documents on matters related to its regulatory mandate. These set out in AECB policies and standards on various matters or provide guidance to licensees on acceptable ways of complying with regulatory requirements. The guidance documents may be incorporated into the regulations of nuclear power stations as binding licence conditions. However, in most cases, licensees use guidance documents to develop their design and/or operating documents, and it is these licensee-produced documents that are incorporated into binding licence conditions.
The regulatory guidance documents include:
• R-7: Requirements for Containment Systems for CANDU Nuclear Power Plants (1991)
• R-8: Requirements for Shutdown Systems for CANDU Nuclear Power Plants (1991)
• R-9: Requirements for Emergency Core Cooling Systems for CANDU Nuclear Power Plants (1991)
• R-10: The Use of Two Shutdown Systems in Reactors (1977)
• R-77: Overpressure Protection Requirements for Primary Heat Transport Systems in CANDU Power Reactors Fitted with Two Shutdown Systems (1987)
• R-90: Policy on the Decommissioning of Nuclear Facilities (1988)
• R-99: Reporting Requirements for Operating Nuclear Power Facilities (1995)
See Attachment 7.9 for copies of these regulatory documents.
Regulatory documents R-7, R-8, R-9 and R-10 contain the principal safety standards that the AECB advises its licensees to meet for the special safety systems:
• the containment system • the shutdown systems
• the emergency core cooling system
Regulatory document R-77 contains the standards for overpressure protection of the primary coolant system in CANDU reactors having two shutdown systems. It
recognizes that the effectiveness of overpressure protection depends on the operation of the two shutdown systems and of the system’s overpressure relief valves.
Regulatory document R-90 contains the AECB’s policy on decommissioning. For new reactors, it advices that a conceptual decommissioning plan be prepared and submitted with the application for construction approval. This is to ensure that the need for eventual decommissioning of the facility was considered in the design. It is also intended to provide a basis for determining the amount of any financial guarantee that may be required to assure adequate financing for decommissioning of the facility.
Regulatory document R-99 contains the general reporting requirements for nuclear power stations. It is referred to in the operating licences, and it represents a minimum set of reporting requirements that all power reactor licensees must comply with. Additional reporting requirements may be imposed on individual licensees through specific licence conditions.
Consultative Document C-6 (Attachment 7.10), and C-6 Rev. 1 currently under preparation, contain the standards for safety analysis of CANDU nuclear power stations. Among other things, they set out the standards for identifying the initiating events to be analysed. For example C-6 Rev. 1 will:
• identify approximately 200 potential initiating events considered to be pertinent to the safety of CANDU nuclear power station;
• recommend a systematic review of the proposed plant by the licensee to identify any additional failures not contained in the general list. The output of the systematic plant review is a complete list of the postulated initiating events that must be analysed for the proposed design.
More about C-6, and C-6 Rev. 1, can be found in the Introduction section, part 4, under the title “The Analytical Technique”.