The Swiss Nuclear Installations Annual Report 1992
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Bundesamtfu' EnergiewiriscnafliScn-eui / JZ W < />/*• U-tL ~\ Office federal ddee !ieoera eoerg* (SuisseI Suisse)) <—'« f ~J \s-ls ( T"-J Uffioo tedera'e dell energia (Svuzerai Federal Office of Energy (SmBertand) HauptabteMung fur die Sicherheit der Kemanlagen Division principale de la Securite des Installations Nucleases Divisione principale delta Sicurezia degli hnpianti Nucleari Swiss Federal Nuclear Safety Inspectorate HSK-AN-2580 KSA-AN-1754 The Swiss Nuclear Installations Annual Report 1992 June 1993 Bundeswm tur Enwgwwiflsctialt (Sctnutiz) Otftet Mirai dc I'tntrgit (Sunt) Ulftoo kdw«t Ml'mis* (Smtnra) FadM OMvt o> Enargy (Sunowwnd) HauptabMfcmg fur dia SichariMil dar Katnanlaojan rMMaiinii niinf ktitt ria la SAcurMe das bistatelions Nudeairas o OivisieiM principala date SJcurazza dagK Impianli Nudaari Swiss FadanJ Nuclaar Safety Inipactorats HSK-AN-2580 KSA-AN-1754 The Swiss Nuclear Installations Annual Report 1992 June 1993 T^is document is also available in German and French. Teieton: 056/993811 (Vermmiung) Postadreaee 056/9939 (Durehwanl) adreu* pottale Hauptabttilung fur die Sicherheit dcr Kernanlagen Telefax: 056/ 993907 Indmao postale CH-5232 Vrlligen-HSK Teiei 827427aakcn Poaicode Contents Page Introduction and Summary 1 Nuclear Power Plant Beznau 2 1.1 Operational Data and Results 2. 1.2 Instattabon Safety 2 1.3 Radiation Protection 6 1.4 Personnel and Organization 8 1.5 HSKExper Report on the Application for an Unlimited Operational LicenseforKKBil ...8 1.6 Overall Judgement by HSK 9 Nuclear Power Plant Muhleberg 10 2.1 Operational Data and Results 10 2.2 Installation Safety 10 2.3 Radiation Protection 15 2.4 Personnel and Organization 16 2.5 Overall Judgement by HSK 17 Nuclear Power Plant Gdagen 18 3.1 Operational Data and Results 18 3.2 Installation Safety 18 3.3 Radiation Protection 21 3.4 Personnel and Organization 22 3.5 Overall Judgement by HSK 23 Nuclear Power Plant Leibstadt 24 4.1 Operational Data and Results 24 4.2 Installation Safety 24 4.3 Radiation Protection 27 4.4 Personnel and Organization 28 4.5 Overall Judgement by HSK 29 Research Installations 30 5.1 Paul Scherrer Institute (PSI), VilligerVWOrenlingen 30 5.2 Swiss Federal Institute of Technology Lausanne (EPFL) 37 5.3 University of Sasle 38 5.4 Experimental Reactor of Lucens (VAKL) 39 Page Radwaste Disposal 40 6.1 Wastes from Reprocessing 40 6.2 Interim Storage 40 6.3 Final Disposal 41 Emergency Planning for the Vicinity of the Nuclear Power Plants 44 7.1 Alarms 44 7.2 Emergency Preparedness of the Cantons 44 7.3 Training in Emergency Planning 45 Transport of Radioactive Materials 46 8.1 Training and Information 46 8.2 Transport Certificates and Inspections 46 8.3 Quality Assurance in the Transport of Radioactive Materials 47 General Matters of Safety and Radiation Protection 48 9.1 Official Guidelines 48 9.2 Measures Against Severe Accidents 48 9.3 Monitoring Network in the Nuclear Power Plants' Vicinity and Plant Parameter Transmission (MADUK-ANPA) 49 9.4 International Collaboration 50 9.5 Safety Research 51 9 6 Incidents in Foreign Nuclear Installations Bearing Impact on the Swiss Installations 52 9.7 Requirements of the New Decree on Radiation Protection 55 9.8 Earthquake Hazard to the Swiss Nuclear Power Plants 56 9.9 Incident Assessment in Nuclear Installations 56 Appendix A1 List of Tables and Figures Page Table 1 a: Basic characteristics of the Swiss nuclear power plants Al Table 1b: 1992 performance of the Swiss nuclear power plants Al Table 2: Numbers for the licensed personnel as of end 1992 A2 Table 3: Reports of plant operators on particular incidents in 1992 A2 Table 4: Overview of the radtoactivity releases to the environment in 1992 A3 and calculated doses to single members of the public. Table 5a/b: Whole-body doses from external irraolation in 1992 A6 Number of persons and average annual dose. Table 6a/b: Whole-body doses from external irraolation in 1992 .A7 Annual collective doses in man-mSv. Table 7: Whole-body doses from external irradiation in 1992 A8 Number of persons, grouped according to age and sex Table 8: Hand doses from external irraolation in 1992, Number of persons A8 Table 9: Incorporations 1992: Number of persons A9 Table 10a/b: Number of persons with lite doses, accumulated at work A10 falling, at the end of 1992, into the follwing dose ranges: Table 11: Nagra's exploratory drillings: status quo as of end 1992 A11 Table 12. List of the HSK guidelines and recommendations (as of end 1992) A12 Table 13: International Nuclear Event Scale ONES) A16 Figure 1: Functioning diagram of a pressurized water reactor A18 Figure 2: Functioning diagram of a boiling water reactor A19 Figure 3: Classified incidents, subject to registration, 1980-1992 A20 Figure 4: Reactor scrams 1980-1992 A21 Figure 5: Fuel rod defects (number of rods) 1979-1992 A22 Figure 6: Annual collective doses (man-Sv/ a) in the nuclear power plants 1980-1992 A23 Figure 7: Annual collective doses (man-Sv/ a) in Swiss nuclear installations A24 from 1969 to 1992 List of abbreviations used A25 -1- Introduction and Summary This report concerns the safety of the Swiss nuclear installations in the pentt of 1992. Surveillance of these installations with regard to nuclear safety, including radtation protection is arnong the tasks of the Swiss Federal Nuclear Safety Inspectorate (HSK). In Switzerland five nuclear power plants are operational: the three units Beznau I and II and MQhleberg with electrical capacities in the range 300 to 400 MWe, and the two units Gosgen and Leibstadt with capacities between 900 and 1200 MWe. These are light water reactors, at Beznau and Gosgen of the pressurized water reactor type, at Muhteberg and Leibstadt of the boiling water type. Research reactors of thermal capacities below 10 MWth are operational at the Paul Scherrer Institute (PSI), at the Swiss Federal Institute of Technology Lausanne and at the University of Basle. Further subject to HSICs supervision are an activities at PSI invcfving nudear fuel o ionizing radiation, the shut down experimental reactor of Lucens, the exploration in Switzerland of final disposal facilities for radwaste and the interim radwaste storage facilities. The present report first deals with the nuclear power plants and covers, in individual sections, the aspects of installation safety, radiation protection as well as personnel and organization, and the resulting overall impression from the point of view of HSK (chapters 1 to 4). In chapter 5, the corresponding information is given for the research installations. Chapter 6 on radwaste Disposal is dedicated to the waste treatment, waste from reprocessing, interim storage and exploration by the National Cooperative for the Storage of Radioactive Waste (Nagra). In chapter 7, the status of emergency planning in the nuclear power plants' vicinity is reported. Certificates issued for the transport of radioactive materials are dealt with in chapter 8. Finally chapter 9 goes into some general questions relating to the safety of nuclear installations, and in particular covers important events in nuclear installations abroad. In the reporting period a total of 15 safety relevant incidents, subject to registration, were recorded in the Swiss nuclear power plants. Among these incidents were two scrams from power operation. Three incidents were registered for the research installations. These events had no harmful effects on the population in the plants' vicinity. All nuclear installations adhered to the annual limits for the release of radioactivity. The radiation doses to members of the public caused by the Swiss nuclear installations were below the authorized limits in all cases. Compared to the public's mean annual radiation exposure of about 5 mSv (1991 report of the Federal Office of Public Health, BAG), the fraction of the dose to any member of the public originating from radioactive discharges of the nuclear installations is less than 1 percent. All in all, the operation of the Swiss nuclear installations in the period of 1992 is rated safe by HSK. -2- 1. Nuclear Power Plant Beznau 1.1 Operational Data and Results The Nuclear Power Plant Beznau (KKB), owned by the Nordostschweizerische Kraftwerke AG (NOK), comprises two nearly identical dual-loop pressurized water reactor units (KKB I and KKB II), each of net capacity 350 MWe, that became operational in 1969 and 1971, respectively. Additional data are summarized in the apperxfx in Table 1. Figure 1 shows the functioning diagram of a pressurized water reactor. Units KKB I and KKB II performed with load factors of 80.9% and 77.6%, respectively, with availability factors of 83.1 % and 77.8%, respectively, while the percentage of unproduced energy is due essentially to fuel exchange and the annual revision. The planned outages for fuel exchange and maintenance lasted 62 days for KKB I and 81 days for KKB II. The downtime of KKB I was somewhat lengthened by extensive preparations for the 1993 installation of the emergency standby system NANO. With KKB II the finishing work on, and taking into operation of, the emergency standby system NANO caused an exceptionally long downtime. The thermal energy fed into the regional public heat supply system of the lower Aare valley (REFUNA) amounted to 113.6 GWh for both units in 1992. The operation of unit KKB I was interrupted by an unplanned outage and one reactor scram. Two load reductions to 50% were necessary to enable fault clearance in the sealing steam system and in a generator transformer. KKB It's operation was interrupted by one scram. Exceptionally high water temperatures at the cooling water intake from the Aare river during the summer months July and August 1992 required a minimal load reduction for a short period to maintain compliance with the water protection regulations.