STUK-B 164 / AUGUST 2013

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Finnish report on nuclear safety

Finnish 6th national report as referred to in Article 5 of the Convention on Nuclear Safety

Säteilyturvakeskus Strålsäkerhetscentralen Radiation and Nuclear Safety Authority STUK-B 164 / AUGUST 2013

Finnish report on nuclear safety

Finnish 6th national report as referred to in Article 5 of the Convention on Nuclear Safety

STUK • SÄTEILYTURVAKESKUS Osoite/Address • Laippatie 4, 00880 STRÅLSÄKERHETSCENTRALEN Postiosoite / Postal address • PL / P.O.Box 14, FIN-00881 Helsinki, RADIATION AND NUCLEAR SAFETY AUTHORITY Puh./Tel. (09) 759 881, +358 9 759 881 • Fax (09) 759 88 500, +358 9 759 88 500 • www.stuk.fi ISBN 978-952-478-828-1 (print) Erweko, Helsinki/Finland 2013 ISBN 978-952-478-829-8 (pdf) ISSN 0781-1713 STUK-B 164

Finnish report on nuclear safety. Finnish 6th national report as referred to in Article 5 of the Convention on Nuclear Safety. STUK-B 164. Helsinki 2013. 80 pp. + Annexes 44 pp.

Keywords: national report, Convention on Nuclear Safety, Finland

Executive summary

Finland signed on 20 September 1994 the Convention on Nuclear Safety which was adopted on 17 June 1994 in the Vienna Diplomatic Conference. The Convention was ratified on 5 January 1996, and it came into force in Finland on 24 October 1996. This report is the Finnish National Report for the Sixth Review Meeting in March/April 2014.

There are two plants operating in Finland: the and Olkiluoto plants. The Loviisa plant comprises of two VVER units (Russian type pressurised water reactors), operated by Power and Heat Oy, and the Olkiluoto plant two BWR units (boiling water reactors), operated by Oyj. In addition, a new unit is being constructed at the Olkiluoto site (PWR). At both sites there are interim storages for spent fuel as well as final disposal facilities for medium and low level radioactive wastes. Posiva, a joint company by Fortum and TVO, submitted a construction licence application for the spent nuclear fuel repository in the end of 2012. Furthermore, there is a Triga Mark II operated in by VTT Technical Research Centre of Finland who has commenced an environmental impact assessment procedure for the decommissioning of the reactor.

In this report, latest development in the various topics of the Convention on Nuclear Safety is described. Major safety reviews and plant modernisations are explained including safety assessment methods and key results. Safety performance of the Finnish nuclear power plants is also presented by using representative indicators. Finnish regulatory practices in licensing, provision of regulatory guidance, safety assessment, inspection and enforcement are also covered. Major developments in Finland since the Fifth Review Meeting are as follows: updating of legislation and regulatory guides, carrying out the safety assessments related to the lessons learnt from the TEPCO Fukushima Dai-ichi accident, IRRS mission (IAEA’s Integrated Regulatory Review Service) carried out in Finland (STUK and other authorities), and continued construction of the new nuclear power plant unit.

In the report, the implementation of each of the Articles 6 to 19 of the Convention is separately evaluated. Based on the evaluation, the following features emphasising Finnish safety management practices in the field of nuclear safety can be concluded: • During the recent years Finnish legislation and regulatory guidance have been further developed and the revised regulatory guide system will be finalised in 2013. The overall revision of the regulatory guides takes into account international guidance such as IAEA standards and WENRA (Western European Regulators’ Association) reference levels for existing reactors and safety objectives for new reactors. In addition, the lessons learnt from the TEPCO Fukushima Dai-ichi accident are taken into account. No deviation from the convention obligations has been identified in the Finnish regulatory infrastructure including nuclear and radiation regulations. • The licensees have shown good safety performance and rigorous safety management practices in carrying out their safety related responsibilities in the operation and modernisation of existing NPPs. During recent years, only minor operational events

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(INES 1 and below) have been taken place and no major safety problems have appeared. The licensees’ practices are considered to comply with the Convention obligations. • Safety assessment is a continuous process and living probabilistic risk assessment (PRA) practices are effectively used for the further development of safety. Periodic safety review of the Loviisa plant was carried out in 2005–2007 in connection with the operating licence renewal, and the periodic safety review of the Olkiluoto plant was carried out in 2007–2009. Several plant modifications have been carried out at the operating NPPs during the recent years to further improve the safety. Safety assessment carried out after the TEPCO Fukushima Dai-ichi accident also identified some further enhancement needs which are being planned and implemented. • The resources of the Radiation and Nuclear Safety Authority (STUK) are adequate to fulfil the needs for independent regulation, and have been increased to meet the needs to oversee the construction of the new plant in Finland. The recent IRRS mission results will be used to further improve regulatory guidance and practices. VTT Technical Research Centre of Finland supports effectively the regulatory body in the safety assessment work providing safety analysis capabilities and tools and performing safety analyses. There are also national research programmes which support and develop the competencies in nuclear safety and waste management also in universities.

The Fifth Review Meeting in 2011 identified some challenges and recorded some planned measures to improve safety in Finland. These issues are included and responded in this sixth national report of Finland. These items were (in brackets the Articles, in which the issues are addressed): • revising the existing regulatory guide system (see Article 7) • response to the Fukushima accident; improvements on national and plant level (see Articles 5, 7, 14, 16, 17, 18, and 19) • aging management of reactors in operation; renewal of I&C systems, reactor pressure vessel material embrittlement and use of risk-informed methods to further develop the plant safety (see Articles 14 and 18) • challenges in new NPP construction project (Olkiluoto unit 3); competence, training and oversight of subcontractors, operating licence application review, compliance with QA programme, adequacy of oversight resources at site (vendor, licensee), and safety culture of organisations and personnel (see Articles 10, 11, 13, and Annex 4) • preparation for the new build (see Annex 5) • maintaining competence and responding to the growing needs for professional staff (see Articles 8 and 11) • ensuring reliability of digital I&C, verification & validation (see Article 18) • integration of safety and security arrangements (see Article 8) • responding to increased demand for timely and effective communication to public (see Articles 8, 16, and 17) • IRRS mission in 2012; results will be used to further improve regulatory practices (see Articles 7, 8, 10, 13, 15, 16, and Annex 6).

Still some of these issues require further development to enhance safety, i.e., including provision for plant ageing, reliability of digital I&C and management of competence taking into account the new build projects and retirement. Other important issues cover

4 STUK-B 164 new technologies, security arrangements and the growing need for new research and development programmes. These are generic issues that require international attention in all countries using nuclear energy.

The existing regulatory guidance system (YVL Guides) is being restructured. The goal is to have updated legislation and new regulatory guides published during 2013. This task is highly prioritised because of new nuclear power plant projects in Finland.

The expected lifetime of the existing nuclear power plants requires renewal of systems and components and modernisation of technologies. The regulation of the existing nuclear power plants emphasises the management of ageing and the quality of plant operations. The I&C and other systems at the Loviisa and Olkiluoto plants are undergoing and planning modernisation, and extra care is needed to ensure operational safety during this work. Operating experience has shown that special attention has to be paid on the meticulous planning and controlled implementation and testing of the plant modifications and STUK is following this in its regulatory inspections.

Security arrangements in the use of nuclear power also call for efficient supervision. The procedures, preparations and information exchange related to antiterrorism activities need to be enhanced worldwide. In Finland, the need for strengthened security has been addressed in the amended legislation and regulatory guidance. IAEA’s International Physical Protection Advisory Service (IPPAS) mission was carried out in Finland in 2009 and the follow-up in 2012. As a result, STUK has increased its resources in the security area and its co-operation with other authorities.

The retirement of large age groups in Finland will affect public administration and industry throughout, including STUK, utilities and the spent fuel management company Posiva as well as organisations providing technical support and education to them. The plans for new NPP construction projects and the above mentioned challenges and activities require additional manpower and efforts from the nuclear power utilities and regulatory body as well as from technical support organisations. Thus, ensuring an adequate national supply of experts in nuclear science and technology and ensuring high quality research infrastructure are continuous challenges in Finland. During 2010–2012 a committee set up by the Ministry of Employment and the Economy worked on a report aiming at giving recommendations and steps to be taken until the 2020’s for ensuring competence and resources needed for the nuclear sector. In addition, the Ministry of Employment and the Economy set up at the end of January 2013 a working group to prepare a research and development strategy. Education and training programmes have been developed for newcomers at STUK as well as on national level to all organisations (such as utilities, waste management company and research organisations).

Due to the increasing interest in , communication and information sharing on nuclear and radiation safety has become an increasingly important success factor for STUK and utilities. Regulatory processes and decisions have to be clear and understandable to general public. Interactions with media are important since media plays an important role in communication.

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Actions taken as a result of the TEPCO Fukushima Dai-ichi accident

Following the accident at the Fukushima Dai-ichi nuclear power plant on the 11th of March in 2011 (TEPCO Fukushima Dai-ichi accident), safety assessments in Finland were initiated after STUK received a letter from the Ministry of Employment and the Economy on 15 March 2011. The Ministry asked STUK to carry out a study on how the Finnish NPPs have prepared against loss of electric power supply and extreme natural phenomena in order to ensure nuclear safety. STUK asked the licensees to carry out assessments and submitted the study report to the Ministry of Employment and the Economy on 16 May 2011. Although immediate actions to ensure safety of public and environment were not considered necessary, STUK required the NPP licensees to carry out additional assessments and present action plans for safety improvements. Assessments were conducted and reported by the Finnish licensees to STUK on 15 December 2011. STUK has reviewed the results of national assessments, and made licensee specific decisions on 19 July 2012 on the suggested safety improvements and additional analyses.

Finland also participated in the EU Stress Tests and submitted the national report to European Commission at the end of 2011. An EU level peer review on the report was completed by April 2012. The recommendations of the EU peer review have been taken into account in the regulatory decisions and will be considered in the development of national regulations. A National Action Plan was prepared addressing the measures initiated on a national level and at the nuclear power plants as a result of the TEPCO Fukushima Dai-ichi accident. The National Action Plan was sent to the European Nuclear Regulators Group (ENSREG) and peer reviewed in April 2013. In addition, Finland participated in the second Extraordinary Meeting of the Convention of Nuclear Safety (CNS) in August 2012 and prepared a report introducing all Fukushima related actions. All STUK’s related decisions, the national report to European Commission, the report to the Extraordinary CNS, and the Finnish National Action Plan have been published on STUK’s website.

Based on the results of assessments conducted in Finland to date, it is concluded that no such hazards or deficiencies have been found that would require immediate actions at the Finnish NPPs. However, areas where safety can be further enhanced have been identified and there are plans on how to address these areas. The experiences from the TEPCO Fukushima Dai-ichi accident are also taken into consideration in the ongoing renewal of the legislation and Finnish Regulatory Guides (YVL Guides) and in the nuclear safety research programme (SAFIR 2014), see Articles 7 and 8.

In addition to the periodic safety reviews carried out at the nuclear power plants, an extraordinary review of site related issues was performed after the TEPCO Fukushima Dai-ichi accident in connection with the so called European stress tests. Assessment of the safety margins and effects of exceeding the design basis values have been available and utilised for all identified relevant hazards (including extreme weather conditions) in connection with external events probabilistic risk assessments (PRA) which are mandatory for the Finnish NPPs. The stress tests did not reveal any new site-related external hazards or vulnerabilities of the plants to external events. No need for immediate action was recognised, but some additional studies of external hazards and feasibility studies for plant modifications to improve robustness against external events were found justified (see Article 17). For example at the Loviisa NPP, protection against high seawater level will be enhanced and detailed structural analysis of spent fuel pools in the case of an earthquake with consequential boiling in the pools will be carried out. At the Olkiluoto NPP, structural

6 STUK-B 164 analysis of the spent fuel pools has been studied and seismic walk-downs of the fire extinguishing water system have been performed.

The systems needed for residual heat removal from the reactor, containment and spent fuel pools require external power at both Finnish NPPs. At both sites, the ultimate heat sink is the sea. Depending on the design features of the plant, the time margins to withstand station blackout and loss of ultimate heat sink vary. A reliable supply of electrical power to the systems providing for basic safety functions at the Finnish NPPs is ensured by the Defence-in-Depth concept. As a result of multiple and diversified electrical power sources at different levels, the probability of loss of all electrical supply systems is considered very low at the Finnish NPPs. However, as a result of the studies made after the TEPCO Fukushima Dai-ichi accident, further changes are expected to be implemented at the both NPPs (see Article 18). Examples of improvements under planning for the Loviisa NPP include installation of independent cooling towers for decay heat removal from the reactor core and from the spent fuel pools and diverse cooling of the spent fuel pools. Cooling towers were considered already before the Fukushima Dai-ichi accident due to the increased risks of oil transport on the Finnish Gulf. Safety improvement examples at the Olkiluoto units 1 and 2 include ensuring cooling of the reactor core in case of total loss of AC systems, ensuring operation of the auxiliary feed water system pumps independently of availability of the sea water systems, and plans for diverse cooling of the spent fuel pools.

A comprehensive severe accident management (SAM) strategy has been developed and implemented at the operating Finnish NPPs during 1980’s and 1990’s after the accidents in TMI and Chernobyl (see Annexes 2 and 3). These strategies are based on ensuring the containment integrity which is required in the existing national regulations. STUK has reviewed these strategies and has made inspections in all stages of implementation. As a result of the studies made after the TEPCO Fukushima Dai-ichi accident, no major changes at the plants are considered necessary. However, the licensees are expected to consider ensuring the cooling of spent fuel pools in the SAM procedures (see Article 19). In addition, there are many actions related to the update of the emergency plans (see Article 16). Both NPPs were required to clarify and update their emergency preparedness plans with respect to issues like the possibility of several reactor units’ simultaneous accident, evaluation of the suitability of emergency response personnel to their duties, management of access control and contamination control in the case when the normal arrangements are out of function and restoring the access routes and connections to the site in case of massive destruction of the infrastructure.

Fukushima related modifications at the Loviisa and Olkiluoto NPPs are described in more detail also in Annexes 2, 3 and 4.

Concerning the off-site emergency preparedness and response (see Article 16), there is a need to ensure accessibility to the site in case of extreme weather conditions, provide a sufficient amount of radiation protection equipment and radiation monitoring capabilities for rescue services and improve communication capabilities. The rescue planning is strengthened in a co-operation between the nuclear power utility, regional rescue services, regional police departments and STUK. In addition, a National Nuclear Power Plant Emergency Preparedness Forum is needed in order to have co-operation and combination between permanent groups and the establishment of the National Forum has been agreed. The Ministry of the Interior and the Ministry of Social Affairs and Health, the regional rescue service authorities, STUK and the NPP licensees will be participating in the Forum.

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In conclusion, Finland has implemented the obligations of the Convention and also the objectives of the Convention are complied with. Safety improvements have been annually implemented at the Loviisa and Olkiluoto plants since their commissioning. Legislation and regulatory guidance have been further developed taking into account nuclear safety research and advances in science and technology as well as the operating and construction experiences. Additional safety assessments and implementation plans for safety improvements have been made at the Loviisa and Olkiluoto plants based on the lessons learnt from the Fukushima Dai-ichi accident. IRRS mission (IAEA’s Integrated Regulatory Review Team) was carried out in October 2012 and STUK has developed its action plan for improvement on the basis of the IRRS mission results and the self-assessment. There exists no urgent need for additional improvements to upgrade the safety of the Finnish nuclear power plants in the context of the Convention.

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Contents

EXECUTIVE SUMMARY 3

1 INTRODUCTION 11

2 COMPLIANCE WITH ARTICLES 6 TO 19 – ARTICLE-BY-ARTICLE REVIEW 12 Article 6. Existing nuclear installations 12 Loviisa NPP units 1 and 2 13 Olkiluoto NPP units 1 and 2 15 Olkiluoto NPP unit 3 16 Article 7. Legislative and regulatory framework 17 Legislative and regulatory framework 17 Provision of regulatory guidance 18 System of licensing 20 System of regulatory inspection and assessment 22 Enforcement 23 Article 8. Regulatory body 24 STUK in the regulatory framework 24 Finance and resources of STUK 26 Ensuring competence 28 Article 9. Responsibility of the licence holder 29 Article 10. Priority to safety 30 Regulatory requirements regarding safety culture and safety management 30 Measures taken by licence holders 31 Regulatory oversight 32 Means used by regulatory body in its own activities 32 Article 11. Financial and human resources 33 Financial resources 33 Human resources 34 Article 12. Human factors 36 Regulatory requirements regarding human factors 36 Measures taken by licence holders 36 Regulatory oversight 38 Article 13. Quality assurance 39 Regulatory requirements regarding management systems 39 Measures taken by licence holders 39 Regulatory oversight 40 Management system of the regulatory body 40 Article 14. Assessment and verification of safety 41 Regulatory approach to safety assessment 41 Deterministic safety assessment 42 Probabilistic risk assessment 43 Assessment of safety as a result of TEPCO Fukushima Dai-ichi accident 47 Verification of safety 48

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Article 15. Radiation protection 52 Regulatory requirements regarding radiation protection 52 Radiation doses of NPP workers 52 Radioactive effluents 54 Environmental radiation monitoring 55 Regulatory oversight 56 Article 16. Emergency preparedness 56 Emergency preparedness on-site of NPPs 56 Off-site preparedness arrangements 58 Information to the neighbouring countries 59 Article 17. Siting 60 Regulatory approach to siting 60 Re-evaluation of site related factors 61 Article 18. Design and construction 63 Implementation of defence in depth 63 Incorporation of proven technologies 67 Design for reliable, stable and manageable operation 68 Article 19. Operation 69 Initial authorisation 69 Operational Limits and Conditions 70 Procedures for operation, maintenance, inspection and testing 71 Procedures for responding to operational occurrences and accidents 73 Engineering and technical support 74 Reporting of incidents significant to safety 74 Operational experience feedback 75 Management of spent fuel and on the site 77

ANNEX 1 List of main regulations 81

ANNEX 2 Loviisa NPP units 1 and 2 under operation 84

ANNEX 3 olkiluoto NPP units 1 and 2 under operation 98

ANNEX 4 olkiluoto NPP unit 3 under construction 110

ANNEX 5 olkiluoto NPP unit 4 and Hanhikivi NPP unit 1 in planning phase 114

ANNEX 6 implementation of the IAEA Action Plan on Nuclear Safety 117

REFERENCE 1 Regulatory oversight of nuclear safety in Finland, Annual Report 2012 REFERENCE 2 Nuclear , 2011 REFERENCE 3 Annual Report 2012, Fortum Corporation REFERENCE 4 Annual Report 2012, Teollisuuden Voima Oyj REFERENCE 5 European Stress Tests for Nuclear Power Plants, Finnish National Report 2011 REFERENCE 6 Convention on Nuclear Safety, Second Extraordinary Meeting, Finnish National Report, 2012 REFERENCE 7 European Stress Tests for Nuclear Power Plants, Finnish National Action Plan, 2012 REFERENCE 8 Integrated Regulatory Review Service (IRRS) report to Finland, 2012 REFERENCE 9 STUK’s Action Plan based on STUK’s self-assessment and IRRS findings, 2013 REFERENCE 10 Report of the Committee for Nuclear Energy Competence in Finland, 2012

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1 Introduction

Finland signed on 20 September 1994 the performance of Finnish nuclear power plants is Convention on Nuclear Safety which was adopt- also presented by using representative indicators. ed on 17 June 1994 in the Vienna Diplomatic The topics of the Second Extraordinary Meeting Conference. The Convention was ratified on 5 of the Contracting Parties to the Convention of January 1996, and it came into force in Finland Nuclear Safety are discussed under applicable on 24 October 1996. This report is the Finnish Articles. Finnish regulatory practices in licensing, National Report for the Sixth Review Meeting in provision of regulatory guidance, safety assess- March/April 2014. ment, inspection and enforcement are also covered In Chapter 2 of this report, the measures relat- in detail. The results of the latest IRRS mission ed to each of the Articles 6 to 19 of the Convention (IAEA’s Integrated Regulatory Review Service) are separately evaluated. The evaluation is based carried out in Finland in October 2012 are de- on the Finnish legislation and regulations as well scribed under Article 8 and detailed actions related as on the situation at the Finnish nuclear power to recommendations and suggestions under appli- plants. The reference is made to the IAEA Safety cable Articles. Requirements and other safety standards as ap- The sixth National Report is aimed to be a propriate. IAEA’s Information Circular 572, Rev. 4, stand-alone document and does not require famil- 28 January 2013, was used as a guideline for the iarisation with the earlier reports. The fulfilment context of the report. of the obligations of the Convention is described in In the report, latest safety reviews and plant general and the latest development since the Fifth modernisations are explained in detail including Review Meeting is specifically described. safety assessment methods and key results. Safety

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2 Compliance with Articles 6 to 19 – Article-by-article review

Article 6. Existing nuclear installations erational in about 2022. The Decision-in-Principle Each Contracting Party shall take the ap- (DiP) on the spent fuel disposal facility in deep propriate steps to ensure that the safety of crystalline bedrock was made by the Government nuclear installations existing at the time in 2000 and ratified by the Parliament in 2001. In the Convention enters into force for that the connection of approving the DiP in May 2002 Contracting Party is reviewed as soon as pos- for the construction of the fifth power reactor in sible. When necessary in the context of this Finland, the Parliament also approved the DiP Convention, the Contracting Party shall en- for expanding the capacity of the planned spent sure that all reasonably practicable improve- fuel disposal facility in Olkiluoto to also include ments are made as a matter of urgency to the spent fuel from this new reactor unit. The re- upgrade the safety of the nuclear installation. pository will be constructed in the vicinity of the If such upgrading cannot be achieved, plans Olkiluoto NPP site. To confirm the suitability of the should be implemented to shut down the nu- site, construction of an underground rock charac- clear installation as soon as practically possi- terisation facility was commenced in 2004. Posiva ble. The timing of the shut-down may take into submitted a construction licence application for account the whole energy context and possible the spent nuclear fuel repository to the Ministry of alternatives as well as the social, environmen- Employment and Economy in the end of 2012. The tal and economic impact. detailed technical documentation of the application In Finland, there are two nuclear power plants: is planned to be reviewed by STUK during 2013- the Loviisa and Olkiluoto plants. The Loviisa plant 2014 and based on the review STUK will give a comprises of two VVER units that are operated safety assessment for the Ministry of Employment by Fortum Power and Heat Oy (Fortum), and the and Economy during 2014. Olkiluoto plant comprises of two BWR units that Three new nuclear power plant units have are operated by Teollisuuden Voima Oyj (TVO). been under consideration in Finland (see more TVO has also a Construction Licence for the new details of the licensing process under Articles 7 plant unit of nominal reactor thermal power 4300 and 17). Environmental Impact Assessment (EIA) MW at the Olkiluoto site (Olkiluoto unit 3). At both procedures were carried out in 2007–2009. In sites there are fresh and spent fuel storage facili- May 2010, the Government granted two Decision- ties, and facilities for storage and treatment of low in-Principles for new reactor units, one to TVO and medium level radioactive wastes. Other exist- (Olkiluoto site) and another to Oy (al- ing nuclear installations in Finland are the final ternative sites in Pyhäjoki and Simo). At the same disposal facilities for low and medium level ra- time the Government rejected Fortum’s DiP appli- dioactive waste at the Olkiluoto and Loviisa plant cation to construct a new reactor unit to the Loviisa sites. The disposal facility at Olkiluoto was taken site. The Government also granted a Decision-in- into operation in 1992 and at Loviisa in 1998. Principle applied by the spent fuel management For taking care of the spent fuel final disposal, company Posiva Oy for expanding the capacity of a joint company Posiva Oy has been established in the planned spent fuel disposal facility in Olkiluoto 1995 by Fortum and TVO. Research, development to also include spent fuel from Olkiluoto unit 4. and planning work for spent fuel disposal is in pro- The Parliament ratified all granted DiPs in July gress and the disposal facility is envisaged to be op- 2010. The Decision-in-Principles set a schedule for

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Fennovoima and TVO to conclude their licensing and advances in science and technology. The im- feasibility studies, bidding processes and prepara- plementation of safety improvements has been a tions for the construction licence applications to continuing process at both Finnish nuclear power the Government by mid 2015. plants since the commissioning of the operating In its application to build a nuclear power plant reactor units and there exists no urgent need to Fennovoima did not present a plan for disposal of upgrade the safety of these plants in the context of spent fuel. The DiP regarding Fennovoima’s ap- the Convention. plication includes a requirement that Fennovoima shall further develop its plan for spent fuel dispos- Loviisa NPP units 1 and 2 al. The first option required that Fennovoima shall The reactor units at the Loviisa nuclear power present to Parliament before end of June 2016 an plant were connected to the electrical grid in agreement on co-operation with the present licen- February 8, 1977 (Loviisa 1) and November 4, 1980 sees (TVO and Fortum) under the waste manage- (Loviisa 2). The nominal thermal power of both of ment obligation regarding nuclear waste manage- the Loviisa units is 1500 MW (109% as compared ment. According to the second option Fennovoima to the original power of 1375 MW). The increase of shall prepare within six years a programme for the power level was implemented and licensed in environmental impact assessment for its own facil- 1998. ity taking care of the final disposal of spent fuel. The latest overall safety review of the Loviisa In March 2012, the Ministry of Employment and plant took place in 2005–2007 in connection of the Economy appointed a working group to steer the relicensing of the operation of the plant. The nuclear power companies’ joint investigation of the Loviisa plant was reaching its original design age alternatives available for final disposal of nuclear in 2007–2010, but the technical and economical fuel. The working group’s final report assesses the lifetime of the plant is estimated to be at least 50 environmental impacts of the various options (one years according to the current knowledge of the or two final disposal facilities in Finland), safety, plant ageing. Based on the application, Radiation costs and a review of these with respect to the and Nuclear Safety Authority (STUK) carried out overall interests of society. In the working group’s a comprehensive review of the safety of the Loviisa opinion, both options can be safely implemented. plant. The review was completed in July 2007 Finland observes the principles of the when STUK provided the Ministry of Employment Convention, when applicable, also in other uses and the Economy (former Ministry of Trade and of nuclear energy than nuclear power plants, e.g. Industry) with its statement on the safety of the in the use of a research reactor. In Finland, there plant (see more details in Annex 2). The Finnish is one TRIGA Mark II research reactor (250 kW), Government granted in July 2007 to Fortum new FiR 1, situated in Espoo. The research reactor was Operating Licences for unit 1 until the end of 2027 taken into operation in 1962, and it is operated by VTT Technical Research Centre of Finland. In 2012, VTT decided to commence the activities re- lated to the planning of the decommissioning of the research reactor. The preparation of the pro- gramme for the environmental impact assessment procedure for the decommissioning of FiR 1 was started in May 2013. In Finland, the continuous safety assessment and enhancement approach is presented in the nuclear legislation. Nuclear Energy Act states that the safety of nuclear energy use shall be maintained at as high a level as practically possible. For the further development of safety, measures shall be implemented that can be considered justified con- Figure 1. Loviisa nuclear power plant units 1 and 2. sidering operating experience and safety research Source: Fortum.

13 STUK-B 164 Article 6 – Existing nuclear instl al ations

and for unit 2 until the end of 2030. The length of units to reduce the risk. Fortum submitted dur- the Operating Licences corresponds to the current ing the latest operating licence renewal process a goal for the plant’s lifetime, which is 50 years. Two comprehensive analysis based on which the brittle periodic safety reviews (by the end of the year 2015 fracture risk can be managed until the end of the and 2023) are to be carried out by the licensee as a 50 years plant lifetime. The permit renewal for the licence condition. use of the reactor pressure vessels was carried out Due to consistent plant improvements, the safe- at the Loviisa unit 2 in 2010 and at the Loviisa ty level of the plant has been increased as shown unit 1 in 2012. STUK approved the applications by the probabilistic risk assessment (see Article to extend the operation of the pressure vessels at 14). For continued safe operation, plant improve- the both units to the end of the operating licence, ment projects are still necessary. The largest ongo- i.e. until the end of 2027 for the Loviisa unit 1 and ing improvement is the complete renewal of the until the end of 2030 for the Loviisa unit 2. plant I&C system, where the safety classified parts The large plant modernisation projects car- of the project are intended to be completed in 2017. ried out at the Loviisa nuclear power plant and Due to the TEPCO Fukushima Dai-ichi acci- STUK’s safety reviews are described in more detail dent, additional safety improvements have been in Article 18 and in Annex 2. During recent years, initiated at the Loviisa NPP. The issues under only minor operational events have been taken planning and implementation include among other place and no major safety issues have appeared things: (see also Article 19). • Installation of independent cooling towers for In addition to the regulatory oversight and safe- decay heat removal from the reactor core and ty assessment, there have been independent safety from the spent fuel pools. The cooling towers reviews conducted by international organisations would provide an alternative ultimate heat sink such as IAEA and WANO (World Association of in case of loss of sea water cooling and they Nuclear Operators). IAEA OSART (Operational were considered already before the Fukushima Safety Review Team) missions have been organ- Dai-ichi accident due to the increased risks of ised at the Loviisa power plant in November 1990 oil transport on the Finnish Gulf. Installation of and March 2007 with a latest follow-up review in the towers is planned for 2014. July 2008. The WANO peer reviews have been car- • Flood protection. The utility has estimated the ried out at the Loviisa nuclear power plant at the effects of high sea level to the plant behav- beginning of 2001 and in March 2010. A follow-up iour. The utility will submit a detailed plan on for the last WANO peer review was carried out in improved flood protection in 2014 (protection April 2012. during annual maintenance shutdown already In 2011, the net production of the Loviisa unit 1 partly implemented). was 4030 GWh and the load factor was 94.7%. The • Design plans of diverse cooling water supply annual refuelling and maintenance outage lasted to the spent fuel pools have been submitted to 17 days. The net production of the Loviisa unit STUK in 2013. 2 was 4040 GWh, the load factor 94.8% and the • Evaluation of the availability of cooling water length of the refuelling and maintenance outage and emergency diesel fuel in case of simulta- was 19 days. The annual collective radiation doses neous accidents at multiple reactor units and were 0.43 manSv and 0.29 manSv for Loviisa units other nuclear facilities at the same site. 1 and 2 respectively. In 2012, the net production of the Loviisa unit 1 Plant lifetime management includes credible pro- was 3650 GWh, the load factor was 84.0% and the cedures for the follow-up of the plant ageing. The refuelling and maintenance outage lasted 54 days. conditions of components which are practically The net production of the Loviisa unit 2 was 3960 impossible to be replaced by new ones (pressure GWh, the load factor was 91.3%, and the refuelling vessel, steam generators, etc.) are monitored most and maintenance outage lasted 20 days. The collec- actively. One specific issue with Loviisa plant units tive radiation doses in 2012 were 1.35 manSv for is the risk of reactor pressure vessel brittle frac- the Loviisa unit 1 and 0.33 manSv for the Loviisa ture. Several modifications have been made at both unit 2.

14 Article 6 – Existing nuclear instl al ations STUK-B 164

Olkiluoto NPP units 1 and 2 • Design plans of diverse cooling water supply to The Olkiluoto nuclear power plant units were the spent fuel pools will be completed in 2013. connected to the electrical network in September • The utility is assessing plans for new mobile 2, 1978 (Olkiluoto 1) and February 18, 1980 equipment (diesel generators, pumps). (Olkiluoto 2). The nominal thermal power of both • Evaluation of the availability of cooling water Olkiluoto units is 2500 MW, which was licensed in and emergency diesel fuel in case of accidents 1998. The new power level is 115.7% as compared at multiple reactor units and other nuclear fa- to the earlier nominal power 2160 MW licensed in cilities at the same site. 1983. The original power level of both units was 2000 MW. The Operating Licences of the units are The large plant modernisation projects carried out valid until the end of 2018. at the Olkiluoto nuclear power plant and STUK’s The latest periodic safety review (PSR) of safety reviews are described in more detail in the Olkiluoto plant took place in 2007–2009. Annex 3. During recent years, only minor opera- Regulatory guide YVL 1.1 specifies the contents tional events have taken place and no major safety of the PSR. For a separate periodic safety review issues have appeared (see also Article 19). without operating licence renewal, STUK shall In addition to the regulatory safety assess- be provided with similar safety-related reports as ment, there have been independent safety reviews in applying for the operating licence or operating conducted by international organisations. IAEA licence renewal. STUK made a decision concerning OSART mission has been organised at Olkiluoto the PSR in October 2009. The decision included in March 1986. The WANO peer reviews have been also STUK’s safety assessment which provided a carried out at the Olkiluoto nuclear power plant in summary of the reviews, inspections and continu- 1999, in 2006 with a follow-up review in 2009, and ous oversight carried out by STUK. in 2012. Due to the TEPCO Fukushima Dai-ichi acci- In 2011, net production at the Olkiluoto unit dent, additional safety improvements have been 1 was 7290 GWh and the load factor 94.8%. The initiated at the Olkiluoto NPP units 1 and 2. The annual refuelling and maintenance outage of the issues under planning include among other things: Olkiluoto unit 1 lasted 9 days. The net production • Assessing possibilities to ensure cooling of the of the Olkiluoto unit 2 was 6910 GWh and the reactor core in case of total loss of AC supplies load factor was 90.9%. The annual refuelling and and systems. Evaluations of feasible solutions maintenance outage of the Olkiluoto unit 2 lasted are under way. 29 days. The collective radiation doses in 2008 • Ensuring operation of the auxiliary feed water were 0.21 manSv for the Olkiluoto unit 1 and 0.76 system pumps independently of availability of manSv for the Olkiluoto unit 2. the sea water cooling systems. The modification In 2012, net production at the Olkiluoto unit 1 is planned for 2014–2015. was 6970 GWh and the load factor was 90.4%. The annual refuelling and maintenance outage of the Olkiluoto unit 1 lasted 31 days. The net produc- tion of the Olkiluoto unit 2 was 7480 GWh and the load factor was 96.9%. The annual refuelling and maintenance outage of the Olkiluoto unit 2 lasted 9 days. The collective radiation doses in 2012 were 0.53 manSv for the Olkiluoto unit 1 and 0.19 manSv for the Olkiluoto unit 2.

Figure 2. Olkiluoto nuclear power plant units 1 and 2. Source: TVO.

15 STUK-B 164 Article 6 – Existing nuclear instl al ations

Olkiluoto NPP unit 3 a pre-OSART (Operational Safety Review Team) Construction Licence application for the fifth nu- mission to Olkiluoto NPP before the fuel loading. clear power plant unit in Finland on the Olkiluoto Licensing and construction of the Olkiluoto unit 3 site was submitted by TVO to the Ministry of is described in more detail in Annex 4. Trade and Industry (predecessor of the Ministry of Due to the TEPCO Fukushima Dai-ichi ac- Employment and the Economy) in January 2004. cident, additional safety improvements have also The new unit, Olkiluoto 3 is a 1600 MWe European been initiated for the Olkiluoto NPP unit 3. The Pressurised Water Reactor (EPR), the design of licensee has assessed possibilities to implement which is based on the French N4 and German external feed water connections to the steam gen- Konvoi type PWR’s. A turn key delivery is pro- erator secondary side, connections to external AC vided by the Consortium NP and . power supply and external make-up water injec- The technical requirements for Olkiluoto unit tion into the reactor cooling system during refuel- 3 were specified by using the European Utility ling outages in order to have independent means Requirements (EUR) document as a reference. to fulfil residual heat removal function in case TVO’s specifications complemented the EUR plant’s normal systems are inoperable. In the fuel mainly in those points where Finnish require- building, the possibility to use fire extinguishing ments are more stringent. STUK gave its state- water systems for coolong the spent fuel pools and ment in January 2005 on nuclear safety based on boiling-out of the pool water have been evaluated. the review of the licensing documentation and the Additional mobile pumps to provide water injection Government issued the Construction Licence in into the fire fighting water system are to be ac- February 2005. quired before the start of operation of the Olkiluoto Construction work is going on and next li- unit 3. censing step is the Operating Licence. Operating In conclusion, Finnish regulations and practices Licence is needed prior to loading nuclear fuel are in compliance with Article 6. into the reactor core. IAEA has agreed to carry out

Figure 3. Olkiluoto NPP unit 3 in construction phase in April 2013. Source: TVO.

16 STUK-B 164

Article 7. Legislative and The current radiation protection legislation is regulatory framework based on the Radiation Act and Decree, both of 1. Each Contracting Party shall establish which are from 1991 and take into account the and maintain a legislative and regulatory ICRP Publication 60 (1990 Recommendations of framework to govern the safety of nuclear the International Commission on Radiological installations. Protection). Section 2, General principles, and 2. The legislative and regulatory framework Chapter 9, Radiation work, of the Act are applied shall provide for: to the use of nuclear energy. i. the establishment of applicable nation- The Nuclear Energy Act was amended in 2011 al safety requirements and regulations; to include provisions on mining and milling op- ii. a system of licensing with regard to nu- erations aimed at producing or thorium. clear installations and the prohibition In 2012, the Nuclear Energy Act was amended of the operation of a nuclear installa- with some minor clarifications and to extend the tion without a licence; use of inspection organisations. Some other minor iii. a system of regulatory inspection and amendments were also made during 2011–2012 in assessment of nuclear installations to nuclear and radiation legislation to reflect changes ascertain compliance with applicable of other legislation. Amendments in other national regulations and the terms of licences; legislation have not caused essential changes to iv. the enforcement of applicable regu- the regulatory control of nuclear facilities nor to lations and of the terms of licences, the safety requirements set for them. including suspension, modification or Finland is a Member State of the European revocation. Union. In 2011 some amendments were done in the Nuclear Energy Act due to the Nuclear Safety Legislative and regulatory framework Directive (Council Directive 2009/71/Euratom). In The current nuclear energy legislation in Finland 2013, the Nuclear Energy Act and the Radiation (see Annex 1) is based on the Nuclear Energy Act Act are under an amendment process to imple- originally from 1987. The Act has been amended 22 ment the Directive 2011/70/Euratom of 19 July times during the years it has been in force: most 2011 establishing a Community framework for the changes are minor and originate from changes to responsible and safe management of spent fuel and other Finnish legislation. In 2008, nuclear energy radioactive waste. legislation was updated to correspond to current In 2012, the Finnish regulatory framework for level of safety requirements and the new Finnish nuclear and radiation safety was reviewed in the Constitution which came into force in 2000. IRRS (Integrated Regulatory Review Service) peer Together with a supporting Nuclear Energy Decree review process. According to the IRRS recommen- originally from 1988, the scope of this legislation dations, some amendments need to be considered covers e.g. for the legislation concerning mainly the independ- • the construction and operation of nuclear fa- ency of STUK. The amendments to the Nuclear cilities; nuclear facilities refer to facilities for Energy Act and the Radiation Act are being pre- producing nuclear energy, including research pared in 2013. reactors, facilities for extensive disposal of nu- Based on the Nuclear Energy Act, the clear wastes, and facilities used for extensive Government issued in 2008 the following regula- fabrication, production, use, handling or storage tions: of nuclear materials or nuclear wastes • Government Decree on the Safety of Nuclear • the possession, fabrication, production, transfer, Power Plants (733/2008) handling, use, storage, transport, export and • Government Decree on the Security in the Use import of nuclear materials and nuclear wastes of Nuclear Energy (734/2008) as well as the export and import of ores and ore • Government Decree on Emergency Response concentrates containing uranium or thorium. Arrangements at Nuclear Power Plants (735/2008)

17 STUK-B 164 Article 7 – Lexisl ative adn regul atory fr amework

• Government Decree on the Safety of Disposal of cidents (personal injuries). The law amendment Nuclear Waste (736/2008). (2005) has not taken effect yet. It will enter into force at a later date as determined by Government The Decrees 733/2008 and 735/2008 are applied Decree. The entering into force of the amending to a nuclear power plant which is defined to be a act will take place as the 2004 Protocols amending nuclear facility equipped with a for the Paris and Brussels Conventions will enter into the purpose of electricity or heat production or a force. complex consisting of reactor units and other relat- As the ratification of the 2004 Protocols has ed nuclear facilities located on the same plant site. been delayed, Finland made a temporary amend- The regulations are also applied to other nuclear ment in the Finnish Nuclear Liability Act in 2012, facilities to the extent applicable. Decree 734/2008 implementing the provision on unlimited liability is applied to all use of Nuclear Energy, i.e., it covers and requirement of insurance coverage for a mini- all nuclear facilities and activities. mum amount of EUR 700 million by the operator. Decrees 733/2008 and 735/2008 will be amend- The temporary law came into force in January ed in 2013 mainly due to tightening of safety re- 2012 and will be repealed when the 2005 law quirements after the TEPCO Fukushima Dai-ichi amendment takes effect. In Finland, the finishing accident and new WENRA Safety objectives. A off the international ratification process of the con- Government Decree on the safety of mining and vention amendments without any undue delay is milling operations aimed at producing uranium or considered to be extremely important. thorium is being prepared in 2013. As described above, nuclear legislation has been Provision of regulatory guidance amended several times and therefore the Ministry According to Section 7 r of the Nuclear Energy Act, of Employment and the Economy has started an STUK shall specify detailed safety requirements evaluation of the need of a comprehensive reform concerning the implementation of safety level in of the legislation. accordance with the Act. These requirements are At the same time with the international negotia- presented in regulatory guides which are called tions to update the Paris and Brussels Conventions YVL Guides. STUK shall specify the safety re- on Nuclear Liability also the Finnish Nuclear quirements it sets and publish them as part of the Liability Act was reviewed by a special govern- regulations issued by the STUK. mental committee already in 2002. The financial The safety requirements of STUK are binding provisions to cover the possible damage and re- on the licensee, while preserving the licensee’s sulting costs caused by a nuclear accident have right to propose an alternative procedure or solu- been arranged according to the Paris and Brussels tion to that provided for in the regulations. If the Conventions. A remarkable increase in the sum licensee can convincingly demonstrate that the available for compensation of nuclear damages is proposed procedure or solution will implement expected in the future since international nego- safety level in accordance with the Nuclear Energy tiations about the revision of the Paris/Brussels Act, STUK may approve this procedure or solution. agreements on nuclear liability were successfully The procedure to apply new guides to existing completed in 2004. In addition to the revised agree- nuclear facilities is such that the publication of ments, Finland has decided to enact unlimited li- an YVL Guide does not, as such, alter any previ- censee liability by law. This means, that insurance ous decisions made by STUK. After having heard coverage will be required for a minimum amount those concerned, STUK makes a separate decision of EUR 700 million and the liability of Finnish op- on how a new or revised YVL Guide applies to erators shall be unlimited in cases where nuclear operating nuclear power plants, or to those under damage has occurred in Finland and also the third construction, and to licensee’s operational activi- tier of the Brussels Supplementary Convention ties as well as to other nuclear facilities related (providing cover up to EUR 1500 million) has been to nuclear waste management and disposal and exhausted. The revised law will also have some to the research reactor. To new nuclear facilities, other improvements, like extending the claiming however, the guides apply as such. period up to 30 years for victims of nuclear ac- Nowadays the most important references con-

18 Article 7 – Lexisl ative adn regul atory fr amework STUK-B 164 sidered in rulemaking are the IAEA safety stand- regulatory guides in force (see Annex 1). The regu- ards, especially the Requirements-documents, and latory guides have been continuously re-evaluated WENRA (Western European Nuclear Regulators’ for updating. Association) Safety Reference Levels. Also the After amending the nuclear energy legislation in WENRA Safety Objectives for new reactors and 2008, also the revision of the existing nuclear safety the WENRA positions on some key technical issues guide system (YVL Guides) has been commenced. are considered. Other sources of safety informa- The updating of regulatory guides on security ar- tion are worldwide co-operation with other coun- rangements is also included in the ongoing activity. tries using nuclear energy, e.g. OECD/NEA, MDEP The main objectives of this effort on the revision of (Multinational Design Evaluation Programme) the guide system have been the following: and VVER Forum. The Finnish policy is to par- • to restructure the guide system to better reflect ticipate actively in the international discussions the various areas of safety; at the same time on developing safety standards and adopt or adapt to limit the total number of guides and need the new safety requirements into national regula- for cross-referencing between the guides (see tions. At the moment STUK has a set of about 70 Figure 4)

Structure of the new YVL guides

A Safety management of a nuclear facility B Plant and system design

A.1 Regulatory control of the safe use of nuclear energy B.1 Design of the safety systems of a nuclear facility A.2 Siting of a nuclear facility B.2 Classification of systems, structures and A.3 Management systems of a nuclear facility equipment of a nuclear facility A.4 Organisation and personnel of a nuclear facility B.3 Safety assessment a NPP A.5 Construction of a NPP B.4 Nuclear fuel and reactor A.6 Operation and accident management of a NPP B.5 Reactor coolant circuit of a NPP A.7 Risk management of a NPP B.6 Containment of a NPP A.8 Ageing management of a nuclear facility B.7 Preparing for the internal and external A.9 Reporting on the operation of a nuclear facility threats to a nuclear facility A.10 Operating experience feedback of a nuclear facility B.8 Fire protection of a nuclear facility A.11 Security arrangements of a nuclear facility A.12 Control of information security on a nuclear facility

C Radiation safety of a nuclear facility and environment D Nuclear materials and waste

C.1 Structural radiation safety and radiation monitoring D.1 Regulatory control of nuclear non-proliferation of a nuclear facility D.2 Transport of nuclear materials and nuclear waste C.2 Radiation protection and dose control of the personnel D.3 Handling and storage of nuclear fuel of a nuclear facility D.4 Handling of low- and intermediate-level waste and C.3 Control and measuring of radioactive releases decommissioning of a nuclear facility to the environment of a nuclear facility D.5 Final disposal of nuclear waste C.4 Radiological control of the environment of a nuclear facility D.6 Production of uranium and torium C.5 Emergency preparedness arrangements of a NPP

E Structures and equipment of a nuclear facility

E.1 Inspection, testing and certifying organisations E.6 Buildings and structures of a nuclear facility E.2 Manufacture and use of nuclear fuel E.7 Electrical and I&C equipment of a nuclear facility E.3 Pressure vessels and pipings of a nuclear facility E.8 Valve units of a nuclear facility E.4 Verification of strength of pressure equipment of E.9 Pump units of a nuclear facility a nuclear facility E.10 Emergency power supply of a nuclear facility E.5 In-service inspections of pressure equipment of E.11 Hoisting and transfer equipment of a nuclear facility a nuclear facility E.12 Testing organisations in nuclear facilities

Figure 4. The re-structured system of regulatory YVL Guides.

19 STUK-B 164 Article 7 – Lexisl ative adn regul atory fr amework

• to compile requirements concerning related and spent fuel storages, consideration of severe safety issues to the same guide making it easier external hazards and with the requirements con- to use by the licensees and other stakeholders; cerning on-site emergency preparedness including also they will be coupled to the stage of licens- multi-unit accidents. ing process • to rewrite the separate requirements in such System of licensing a way that each requirement will have its own The licensing process is defined in the legislation. number, be short and clearly stating who-what- The construction and operation of a nuclear facility when shall be doing something; requirements is not allowed without a licence. The licences are are expressed in shall-format, descriptive text been prepared by the Ministry of Employment and is provided only when necessary in the guide the Economy and granted by the Government. The itself and additional information is provided in conditions for granting a licence are prescribed in a separate justification memorandum (bases of the Nuclear Energy Act. the guide) Before a Construction Licence for a nuclear • when considering the requirements, special at- power plant, nuclear waste disposal facility, or tention is paid to the opportunities to limit un- other significant nuclear facility can be applied, a necessary prescriptiveness Decision-in-Principle by the Government is needed. • to update the contents of the regulatory guides, A condition for granting the Decision-in-Principle especially with the lessons learnt from the Olki- is that the operation of the facility in question is in luoto unit 3 project. line with the overall good of society. The municipal- ity of the intended site of the nuclear facility has to After the TEPCO Fukushima Dai-ichi accident it be in favour of constructing the facility. There shall was decided to include lessons learned from the also be sufficient prerequisites for constructing accident into the revised guides, which has de- the facility according to the Nuclear Energy Act: layed the completion of the new guides. The origi- the use of nuclear energy shall be safe; it shall not nal schedule was to have all of them ready by the cause injury to people, or damage to the environ- end of 2011.The new revised schedule of the overall ment or property. revision of YVL Guides is that all the new guides The coming into force of the Decision-in- will be published during the autumn of 2013. Principle further requires that it will be con- Considering the WENRA Safety Reference firmed by the simple majority of the Parliament. Levels published in 2007 and 2008, the Finnish The Parliament can not make any changes to the policy is to include all of them in the revised Decision; it can only approve it or reject it as it is. regulatory guide system. This is confirmed already The parties involved in the Decision-in-Principle during the work through a systematic approach to process and their tasks are described in Figure earmark all the Reference Levels to certain guides. 5. In Decision-in-Principle phase STUK prepares To include the lessons from the TEPCO a statement on safety and preliminary safety as- Fukushima accident in the new YVL Guides, a sessment concerning the applicant, the proposed detailed plan was prepared in the beginning of plant designs and plant sites. STUK asks also a 2012. Available information from the accident and statements e.g. from the Advisory Commission evaluation reports concerning the accident were on Nuclear Safety and from the Ministry of the considered in the preparation of the plan. Also the Interior concerning the emergency preparedness IAEA Action Plan and the draft WENRA report and physical protection arrangements. on Safety of new NPP designs were considered. For the Construction and Operating Licence The plan was revised in the end of 2012. In this application, the Ministry of Employment and revision the results of the European stress tests the Economy asks STUK’s statement on safety. and the outcomes of the Extraordinary Meeting Construction and Operating Licence documents to to the Convention on Nuclear Safety were con- be submitted to STUK for approval in this phase sidered. The most important changes that will be are defined in Sections 35 and 36 of the Nuclear included in the new YVL Guides due to the TEPCO Energy Decree. STUK asks also statements e.g. Fukushima accident deal with the design of NPPs from the Advisory Commission on Nuclear Safety

20 Article 7 – Lexisl ative adn regul atory fr amework STUK-B 164 and from the Ministry of the Interior. After re- the DiP application of Posiva Oy for spent fuel dis- ceiving all statements for the Construction or posal facility was confirmed by the Parliament in Operating Licence, the Government will make its 2001 and also in connection with confirmation in decision. May 2002 by the Parliament of the Government’s System of licensing was assessed in the IRRS Decision-in-Principle for expanding the capacity of mission conducted in Finland in October 2012. spent fuel disposal facility to cover the spent fuel The IRRS team gave a recommendation that the from the fifth reactor. The Decision-in-Principle Finnish Government should seek to modify the procedure was also applied during the period Nuclear Energy Act so that the law clearly and April 2008 – July 2010 when three applications unambiguously stipulates STUK’s legal authorities for new nuclear power plants (Fennovoima Oy, in the authorization process for safety. In particu- Fortum Power and Heat Oy and TVO), and two lar, the changes should ensure that STUK has the applications for expanding the planned capacity of legal authority to specify any licence conditions the future spent fuel disposal facility in Olkiluoto necessary for safety. were first handled by the Government and subse- Decision-in-Principle procedure was been ap- quently approved by the Parliament (see Article plied several times over the past 13 years. First 14). The DiP application of Fortum regarding the time DiP procedure was applied for a nuclear proposed new Loviisa unit 3 and the correspond- power plant unit during the period November 2000 ing DiP application to expand the capacity of the – May 2002 when Teollisuuden Voima Oyj (TVO) spent fuel disposal facility were not approved by applied a Decision-in-Principle for the fifth NPP the Government. unit in Finland and the Government approved it In accordance with Section 108 of the Nuclear and the Parliament confirmed the approval. The Energy Decree, the different phases of construction DiP procedure was already earlier applied when of a nuclear facility may be begun only after STUK

Public, other authorities, Parliament: Three step and expert organisations Confirms Decision in Principle licensing: • Decision in Principle • Construction Licence Opinions, statements • Operating Licence Government: Makes licensing decisions

Ministry of Employment and the Economy: Conducts preparations

Agreement on site in Statement on safety Decision in Principle Application (veto right)

Regulatory STUK review and Municipality Applicant (regulatory body) oversight of plant site

Advice Safety documents

Expert Nuclear safety Suppliers organisations advisory commission nuclear industry

Figure 5. Licensing of nuclear facilities in Finland.

21 STUK-B 164 Article 7 – Lexisl ative adn regul atory fr amework has, on the basis of the Construction Licence ap- sight performed by STUK’s resident inspectors, plication documents and other detailed plans and regular reporting and reporting of events and over- documents it requires, verified in respect of each sight performed at the plant site during operation phase that the safety-related factors and safety reg- and maintenance outages. ulations have been given sufficient consideration. STUK’s periodic inspection programme is fo- Review of the detailed design of structures and cused on the licensee’s main working processes and equipment can be begun after STUK has found covers the most relevant areas of nuclear power that the system-level design data of the system plant safety. The objective of the inspection pro- concerned are sufficient and acceptable. This as- gramme is to assess the safety level at the plants sessment may take place as part of the review of as well as safety management. Possible problems the Preliminary Safety Analysis Report or sepa- at the plants and in procedures of the operating rate system-specific descriptions, which are subse- organisations are to be recognised. quently added to the Final Safety Analysis Report. Inspection programme has been modified dur- In accordance with Section 109 of the Nuclear ing the years. Latest changes were made in 2012, Energy Decree, STUK oversees the construction of when inspection programme was updated and the facility in detail. The purpose is to ensure that additional tools for organisational oversight was the safety and quality requirements, regulations introduced into all inspections. Each year STUK for pressure equipment and approved plans are defines the programme for the next year, including complied with and that the nuclear facility is con- additional inspections as necessary. In addition to structed in other respects in accordance with the the periodic inspection programmes, STUK con- regulations. In particular, the oversight is aimed to ducts unannounced inspections if seen necessary. verify that working methods ensuring high quality STUK has put special emphasis on the manage- are employed for the construction. ment of the entire inspection programme, includ- Before loading fuel into the reactor, an ing the timely conduct, resource allocation and Operating Licence is needed. The Operating accurate reporting of results, but there are some Licences are granted for a limited period of time. issues which can be further improved. Periodic This period has been at the beginning of Loviisa inspection programme was assessed in the IRRS and Olkiluoto NPP operations five years and then mission conducted in Finland in October 2012. about ten years. The periodic re-licensing has al- The IRRS mission team suggested that STUK can lowed good opportunities for a comprehensive, further enhance the effectiveness of its inspection periodic safety review. Current operating licences activities by enhancing the focus of inspection of the Loviisa and Olkiluoto units are valid for on the most safety-significant areas, by defining about 20 years, but periodic safety reviews (PSRs) more concrete criteria for reactive inspections and are required as a condition of continued operation conducting higher number of unannounced inspec- in the licences. tions. STUK is updating the internal guidance of the periodic inspection programme by the end of System of regulatory inspection year 2013 taking into account the IRRS recommen- and assessment dations and suggestions. In addition, unannounced The legislation provides the regulatory control sys- inspections are included in the yearly inspection tem for the use of nuclear energy. According to programmes. the Nuclear Energy Act, STUK is responsible for In the event review, the safety significance of the regulatory oversight of the safety of the use the event is first evaluated based on the informa- of nuclear energy. The rights and responsibilities tion given by the operator and STUK’s resident of STUK are provided in the Nuclear Energy Act. inspectors. Later operating experience is reported Safety review and assessment as well as inspection to STUK as an event report, which STUK evalu- activities are covered by the regulatory oversight. ates and may require additional information or actions. STUK maintains internal database for Oversight during operation events which disseminates operating experiences STUK’s oversight during plant operation includes and provides easy access to operational event re- periodic inspection programme, continuous over- ports. STUK may assign own investigation team

22 Article 7 – Lexisl ative adn regul atory fr amework STUK-B 164 for events deemed to have special importance, es- censee’s review and assessment process for system, pecially when the operations at the nuclear power structure and component-specific design reviews plant have not been performed as planned and and inspections in the various fields of technology. expected. It is also possible to nominate an inves- Furthermore, the emergency response arrange- tigation team to investigate a number of events ments during construction, physical protection, fire together in order to look for possible generic issues protection and nuclear waste treatment are sub- associated with the events. These inspections are jects of the Construction Inspection Programme as usually conducted by a leadership of the STUK’s far as the scope is considered necessary by STUK. event investigation manager, and an investigation In addition to the above-mentioned inspections, of team includes normally 3–5 experts from STUK or which the licensee is informed in advance, STUK from external organisations nominated on case-by- carries out inspections without prior notice at case basis. its discretion. Construction Inspection Programme Numbers of operational events are followed was also assessed in the IRRS mission and the through STUK’s plant performance indicator sys- recommendations and suggestions given for the tem. Risk significance of operational events is fol- periodic inspection programme of the operating lowed by PRA based indicators. plants concern also the Construction Inspection STUK’s oversight and safety assessment con- Programme. STUK is updating the internal guid- cerning plant modifications is described in Article ance of the Construction Inspection Programme by 14. the end of year 2013. STUK performs inspections on manufacturing Oversight during construction and construction of buildings, concrete and steel In accordance with Section 109 of the Nuclear structures, and components as specified in YVL Energy Decree, STUK oversees the construction Guides. Inspections are determined in details when of the facility in detail. Oversight consists of in- STUK reviews component or structure specific con- spections within the frame of the Construction struction plans. Inspections are defined either as Inspection Programme and inspections on manu- hold or witness points. Licensee is responsible for facturing and construction of systems, structures inviting STUK to perform the inspection at a right and components important to safety. In addition, time. Goal of the inspections is to verify that manu- STUK has four resident inspectors overseeing facturer, vendor and licensee have performed their the construction, installations and commissioning duties as expected and that QC results of manufac- work at the Olkiluoto site. Licensee reports regu- turing and construction are acceptable. In addition, larly about the progress of the construction. STUK performs inspections on installation and To oversee the licensee’s performance in commissioning of systems, structures and compo- a construction project, STUK has established a nents. The safety class of systems, structures and Construction Inspection Programme. The purpose components as well as the complexity of the SSCs of the programme is to verify that the performance are taken into account when determining the scope and organisation of the licensee ensure high-qual- of inspections. On the licensee’s application, STUK ity construction and implementation in accord- may approve separate inspection organisations to ance with the approved designs while complying carry out specified regulatory control duties. with the regulations and official decisions. The Construction Inspection Programme is divided into Enforcement two main levels: the upper level assesses the licen- The Nuclear Energy Act defines the enforcement see’s general operations to manage the construc- system and rules for suspension, modification or tion, such as safety management and safety cul- revocation of a licence. The enforcement system in- ture, organisation, corrective actions programme, cludes provisions for executive assistance if needed the licensee’s expertise and use of expertise and and for sanctions in case the law is violated. The project quality management. The next level, known enforcement tools and procedures of the regulator as the operation level, assesses e.g. project quality are considered to fully meet the needs. assurance, training of the operating personnel, uti- In practice, the enforcement tools include: oral lisation of the PRA, radiation safety issues, and li- notice or written request for action by the inspec-

23 STUK-B 164 tor, and written notice or order for actions by 2. Each Contracting Party shall take the ap- STUK. Actions can include shutting down the propriate steps to ensure an effective sepa- plant operation immediately or decrease of reac- ration between the functions of the regula- tor power and for unlimited time. Legally stronger tory body and those of any other body or or- instruments would be 1) setting a conditional im- ganization concerned with the promotion position of a fine, 2) threatening with interruption or utilization of nuclear energy. or limiting the operation and, 3) threatening that STUK enforces the neglected action to be made at STUK in the regulatory framework the licensee’s expense. According to the Nuclear Energy Act, the over- The repertoire of these tools together with some all authority in the field of nuclear energy is the practical examples for implementing them has Ministry of Employment and the Economy. The been presented in an internal policy document as Ministry prepares matters concerning nuclear part of STUK’s Quality System. energy to the Government for decision-making. In conclusion, Finnish regulations and practices Among other duties, the Ministry of Employment are in compliance with Article 7. and the Economy is responsible for the formulation of a national energy policy. Article 8. Regulatory body The mission of the Radiation and Nuclear 1. Each Contracting Party shall establish or Safety Authority (STUK) is ‘to protect people, so- designate a regulatory body entrusted with ciety, environment, and future generations from the implementation of the legislative and harmful effects of radiation’. STUK is an inde- regulatory framework referred to in Article pendent governmental organisation for the regu- 7, and provided with adequate authority, latory control of radiation and nuclear safety as competence and financial and human re- well as nuclear security and nuclear materials. sources to fulfil its assigned responsibili- STUK is administratively under the Ministry of ties. Social Affairs and Health. Interfaces to ministries

Ministry of Ministry of Social Affairs and Advisory Employment and Health Committee the Economy Administrative authority for Administrative authority for the use of radiation. the use of nuclear energy.

Budget and supervision

STUK – Radiation and Nuclear Expert advice and Safety Authority service Independent regulatory and research organisation.

Ministry of the Interior Ministry for Foreign Affairs Rescue and protection duties in Nuclear safety in neighbour countries. emergency conditions. Non-proliferation of nuclear weapons. Security and physical protection.

Figure 6. Co-operation and interfaces between STUK and Ministries and other organisations.

24 Article 8 – Regulatory body STUK-B 164 and governmental organisations are described in STUK does not grant any construction or op- Figure 6. It is emphasised that the regulatory con- erating licences for nuclear facilities. However, in trol of the safe use of radiation and nuclear energy practice no such licence would be issued without is independently carried out by STUK. No Ministry STUK’s statement where the fulfilment of the can take for its decision-making a matter that has safety regulations is confirmed as described in been defined by law to be on the responsibility Article 7. of STUK. STUK has no responsibilities or duties STUK’s Advisory Committee was established in which would be in conflict with regulatory control. March 2008. Advisory Committee helps STUK to The current Act on STUK was given in 1983 develop its functions as a regulatory, research and and the Decree in 1997. According to the Decree, expert organisation in such a way that the activi- STUK has the following duties: ties are in balance with the society’s expectations • regulatory oversight of safety of the use of nu- and the needs of the citizens. Advisory Committee clear energy, emergency preparedness, security can also make assessments of the STUK’s actions and nuclear materials and give recommendations to STUK. • regulatory control of the use of radiation and An Advisory Commission on Nuclear Safety other radiation practices has been established in 1988 by a Decree. This • monitoring of the radiation situation in Fin- Commission gives advice to STUK on important land, and maintaining of preparedness for ab- safety issues and regulations. The Commission normal radiation situations also gives its statements on licence applications. • maintaining national metrological standards in The Commission has now two international com- its field of activity mittees, one for reactor safety and one for waste • research and development work for enhancing safety issues. In addition, an Advisory Committee radiation and nuclear safety on Radiation Safety has been established for advis- • informing on radiation and nuclear safety is- ing the Ministry for Health and Social Affairs. The sues, and participating in training activities in members of the Advisory Commission on Nuclear the field Safety and the Advisory Committee on Radiation • producing expert services in the field of its ac- Safety are nominated by the Government. tivity To assist STUK’s work in nuclear security, an • making proposals for developing the legislation Advisory Committee on Nuclear Security was es- in the field, and issuing general guides concern- tablished in 2009. The members of the committee ing radiation and nuclear safety come from the various Finnish authorities, and the • participating in international co-operation in nuclear licensees also have their representatives. the field, and taking care of international con- The duties of the committee include the assess- trol, contact or reporting activities as enacted ment of the threats in the nuclear field as well as or defined. consultation to STUK in important security issues. The committee also aims to follow and promote STUK has the legal authority to carry out regula- both the international and internal co-operation in tory oversight. The responsibilities and rights of the field of nuclear security. STUK, as regards the regulation of the use of nu- STUK is responsible for informing the public clear energy, are provided in the Nuclear Energy and media on radiation and nuclear safety. STUK Act. They cover the safety review and assessment aims to communicate proactively, openly, timely of licence applications, and the regulatory over- and understandably. A prerequisite for successful sight of the construction, operation and decommis- communication is that STUK is known among me- sioning of a nuclear facility. The regulatory over- dia and general public and the information given sight of nuclear power plants is described in detail by STUK is regarded as truthful. Communication in the Guide YVL 1.1. STUK has e.g. legal rights to is based on best available information. STUK’s web require modifications to nuclear power plants, to site is an important tool in communication. It is limit the power of plants and to require shutdown important that the web pages are professionally of a plant when necessary for safety reasons, as edited and updated regularly. The information on described in Article 7. web pages must be easy to find and understand-

25 STUK-B 164 Article 8 – Regulatory body able. Internal communication provides the person- Finance and resources of STUK nel information about STUK’s activities and sup- The organisational structure and the responsibili- ports its capability in participating in the external ties within STUK are described in the Management communication. System of STUK. Also processes for regulatory STUK’s role and responsibilities have been as- oversight and other activities of STUK are present- sessed by a peer review. Full-scope IRRT mission ed in the Management System. The organisation of (IAEA’s International Regulatory Review Team) STUK is described in the Figure 7. was carried out in 2000 and a follow-up mission in STUK receives about 33% of its financial re- 2003. IRRS mission (IAEA’s Integrated Regulatory sources through the government budget. However, Review Service) was carried out in October 2012. the costs of regulatory oversight are charged in In the latest IRRS mission, 18 international full to the licensees. The model of financing the experts and 5 IAEA staff members reviewed regu- regulatory work is called net-budgeting model and latory activities in Finland on the basis of IAEA it has been applied since 2000. In this model the Safety Standards, International practices and ex- licensees pay the regulatory oversight fees directly periences and lessons learned from the TEPCO to STUK. In 2012, the costs of the regulatory over- Fukushima Dai-ichi accident. The scope of the sight of nuclear safety were 17 million €. mission was nuclear facilities, except the research STUK has adequate resources to fulfil its re- reactor FiR-1 (preparations for environmental im- sponsibilities. The net-budgeting model makes it pact assessment for decommissioning of this reac- possible to increase for example personnel resourc- tor were commenced earlier in 2012), radiation es based on needs in a flexible way. sources and transport. In its preparations to this At the end of 2012, number of staff in the de- mission, STUK carried out a comprehensive self- partment of Nuclear Reactor Regulation was 115. assessment and developed a preliminary action The number of staff has increased by 9 since the plan for improvement. time of the fifth review meeting. The expertise of As a result of the IRRS mission, the review STUK covers all the essential areas needed in the team recognised several strengths and good prac- oversight of the use of nuclear energy. As needed tices such as effective safety assessment of new STUK orders independent analyses, review and nuclear power plants, STUK’s organisation and assessment from technical support organisations conduction of emergency exercises and active con- to complement its own review and assessment tribution of STUK to the global improvement of work. The main technical support organisation radiation and nuclear safety. They identified also of STUK is the VTT Technical Research Centre areas for improvement, such as a need to strength- of Finland, but also Lappeenranta University of en the legislative framework by embedding in Technology (LUT) and Aalto University (former law the separation of STUK from entities having Helsinki University of Technology) are important. responsibilities or interests that could unduly in- Also international technical support organisations fluence its decisions, enhancing the effectiveness and experts have been used, especially to sup- of STUK inspection activities and implementing of port review and inspection activities related to an independent monitoring programme for the en- Olkiluoto unit 3. vironment of NPPs. STUK has developed its action New personnel have been recruited since 2003 plan for improvement on the basis of the IRRS mis- mainly for the safety review and assessment and sion results and the self-assessment. These actions inspection activities related to the Olkiluoto unit have been included in STUK’s strategy, operating 3. The number of personnel in the department programmes and annual plans. Follow-up mission of Nuclear Reactor Regulation over the period of is preliminarily planned for 2015. 2001–2012 is shown in Figure 8. The resources IAEA’s International Physical Protection used for the oversight of existing nuclear power Advisory Service (IPPAS) mission was carried out plants (Loviisa units 1 and 2 and Olkiluoto units in Finland in 2009 and the follow-up in 2012. 1 and 2), Olkiluoto unit 3 which is under con-

26 Article 8 – Regulatory body STUK-B 164

Director General

Public Relations Management Support

Nuclear Environ- Nuclear Regulation Reactor mental Waste and of Use of Local offices Regulation Radiation Materials Radiation •Olkiluoto Monitoring Regu lation •Loviisa • (Pyhäjoki) •Rovaniemi

Emergency Preparedness

Physical Protection

Regulations

Common Services

STUK’s Expert Services

Figure 7. Organisation of STUK. The total number of staff at the end of 2012 was 358. struction and new plant projects (Loviisa unit 3, Olkiluoto unit 4 and Fennovoima’s unit 1) are shown in Figure 9. Annual volume of the oversight Number of staff at NRR of the Olkiluoto unit 3 construction was about 30 120 man-year in 2012. Starting from year 2003, inspec- 100 tion organisations have been performing construc- 80 tion inspections in lower safety classes. 60

STUK has also increased the number of per- 40 sonnel in the areas of security of nuclear facilities 20 as well as in activities related to nuclear waste 0 management and disposal. In 2009, a separate unit 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 for security with three experts was founded in the department of Nuclear Reactor Regulation and in Figure 8. Number of personnel in the department of the end of 2012, 4 experts worked in this unit. Nuclear Reactor Regulation.

Full time equivalents on oversight (person years) 40 35 30 25 20 15 10 5 0 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 LO1/LO2 LO3 OL1/OL2 OL3 OL4 FV1 Figure 9. Resources used for the regulatory oversight in full time equivalents.

27 STUK-B 164 Article 8 – Regulatory body

Ensuring competence field of nuclear energy. At VTT, about 200 experts The management of STUK highlights the need for are working in the field of nuclear energy, about competent workforce. STUK has adopted a compe- half of them full-time. The total volume of the nu- tence management system and nuclear safety and clear energy research in Finland in the year 2012 regulatory competencies are also emphasised in was over 75 million € (estimate of the Ministry STUK’s strategy. Implementation of the strategy is of Employment and the Economy). This figure reflected into the annual training programmes, on includes research related to use of nuclear energy the job training and new recruitments. The national made in all the stakeholder organisations. Two nuclear safety and waste management research pro- thirds of the research is focused on the final dispos- grammes have an important role in the competence al of the spent fuel. The largest individual organi- building of all essential organisations involved in zations are VTT, LUT (Lappeenranta University of nuclear energy. These research programmes have Technology), GTK (Geological Survey of Finland), two roles: for the first ensuring the availability of and Aalto University (former Helsinki University experts and for the second ensuring the on-line of Technology, HUT). transfer of the research results to the organisations The Nuclear Energy Act was amended in 2003 participating to the steering of the programmes and to ensure funding for a long-term nuclear safe- fostering the expertise. STUK has an important role ty and nuclear waste management research in in the steering of these programmes. Finland. Funds are collected annually from the Most of the professional staff of STUK con- licence holders to a special fund. Regarding nuclear ducting safety assessments and inspections has a safety research the amount of money is propor- degree of university level. The average experience tional to the actual thermal power of the licensed of the staff is about 15 years in the nuclear field. power plants or the thermal power presented in The competence analysis is carried out on regular the Decision-in-Principle. For the nuclear waste basis and the results are used as the basis for the research, the annual funding payments are propor- training programmes and the new recruitments. tional to the current fund holdings for the future The training programme includes internal courses waste management activities. as well as courses organised by external organisa- The research projects are selected so that they tions. On an average 5 % of the annual working support and develop the competences in nuclear hours has been used to enhance the competence. safety and to create preparedness for the regula- An induction programme is set up at STUK tor to be able to respond on emerging and urgent for all new recruited inspectors. In addition to safety issues. The topics of the recent nuclear administrative issues, the induction programme safety research programme (SAFIR2014) are or- includes familiarisation with legislation, regula- ganisation and human factors, automation and tory guidance and regulatory oversight practices. control room, fuel and reactor physics, thermal Programme is tailored to each new inspector and hydraulics, severe accidents, structural safety of followed by the manager. reactor circuit, construction safety, probabilistic STUK has participated in the preparation and safety analysis and development of research in- execution of a basic professional training course frastructure. The amount of money collected from on nuclear safety with other Finnish organisations the licensees in year 2012 was about 5.6 million € in the field. The first 6-week course commenced in for nuclear safety research. The research projects September 2003 and the 11th basic professional have also additional funding from other sources. training course will commence in autumn 2013. The total volume of the programme in 2012 was At the moment, over 600 newcomers and junior 10 million €. As a result of the TEPCO Fukushima experts, of whom more than 70 have been from Dai-ichi accident, a reassessment was made how STUK, have participated in these courses. The the accident should be taken into account, and content and structure of the course has been en- the research programme was supplemented with hanced according to the feedback received from the research topics related to natural hazards and participants. multiple failure events, the adequacy and scope In Finland, VTT Technical Research Centre of of nuclear power plant design basis, mitigating Finland is the largest research organisation in the the impact of accidents (e.g. high concentration of

28 STUK-B 164 boron in the reactor circuit, hydrogen formation commitment to the strong safety culture. The ob- and transport, range of fission products released in vious elements of licensee’s actions to meet these core melt), and the overall life cycle of nuclear fuel responsibilities are strict adherence of regula- including spent fuel pools. tions, prompt, timely and open actions towards The objective of KYT2014 (Finnish Research the regulator in unusual situations, active role programme on Nuclear Waste Management) is to in developing the safety based on improvements ensure the sufficient and comprehensive availabil- of technology and science as well as effective ex- ity of the nuclear technological expertise and other ploitation of experience feedback. In addition to capabilities required by the authorities when com- inspections and safety assessment, the follow-up paring different nuclear waste management ways of licensee’s efforts in achieving results is based on and implementation methods. KYT2014 is divided safety indicators. This system includes indicators into three main categories: e.g. for plant availability, incidents, probabilistic • new and alternative technologies in nuclear risk assessment results, safety system operability, waste management radiation doses to personnel as well as releases to • safety research in nuclear waste management the environment and resulting radiation exposures and to the general public. • social science studies related to nuclear waste Based on the Chapter 7 of the Nuclear Energy management, Act, to ensure that the financial liability for the future management and disposal of nuclear wastes and the main emphasis is on safety related re- and for the decommissioning of nuclear facilities search. The programme is conducted during 2011– is covered, the nuclear power companies are every 2014 and the total annual funding is 2.8 M€, of third year obliged to present estimates for future which State Nuclear Waste Management Fund costs of these operations and take care that the (VYR) covers 1.7 M€. required amount of money is set aside to the State In conclusion, Finnish regulations and practices Nuclear Waste Management Fund. In order to are in compliance with Article 8. provide for the insolvency of the nuclear utilities, they shall provide securities to the Ministry of Article 9. Responsibility of Employment and Economy for the part of finan- the licence holder cial liability which is not yet covered by the Fund. Each Contracting Party shall ensure that At the end of the year 2012, the funded money (2 prime responsibility for the safety of a nuclear 160 million euros) covered most part of the whole installation rests with the holder of the rel- liability (2 238 million euros). Under the Nuclear evant licence and shall take the appropriate Energy Act, nuclear companies should supplement steps to ensure that each such licence holder the fund by payment of 83 million euros in early meets its responsibility. April 2013 (see also Article 11). The responsibility for the safety rests with The arrangements for the Olkiluoto unit 3 will the licensee as prescribed in the Nuclear Energy follow the same lines after the start of the opera- Act. According to Section 9 of the Act, it shall tion. The licensee with a waste management obli- be the licensee’s obligation to assure safe use of gation shall submit the waste management scheme nuclear energy. Furthermore, it shall be the licen- and the calculations of waste management costs, see’s obligation to assure such physical protection which are based on the scheme, to the Ministry and emergency planning and other arrangements, for approval for the first time early enough before necessary to ensure limitation of nuclear damage, beginning the operations producing nuclear waste, which do not rest with the authorities. and at the latest in connection with the operat- It is the responsibility of the regulatory body ing licence application. The waste management to verify that the licensees fulfil the regulations. scheme shall cover all phases of waste manage- This verification is carried out through continuous ment including the decommissioning of the nuclear oversight, safety review and assessment as well facilities and the final disposal of all arising nucle- as inspection programmes established by STUK. ar wastes. The scheme must be sufficiently detailed In its activities, STUK emphasises the licensee’s to allow the calculations for the assessed liability.

29 STUK-B 164

The financial provisions to cover the possible struction and operation of a nuclear power plant. damages to third parties caused by a nuclear ac- The appointment is subject to approval by STUK. cident have been arranged in Finland according The responsible director has a duty to ensure the to the Paris and Brussels Conventions. Related to safe use of nuclear energy and to see that the ar- the revision of the Paris and Brussels Conventions rangements for physical protection and emergency in 2004, Finland has decided to enact unlimited li- preparedness and the safeguards control are com- censee’s liability by law (see Article 7). The revised plied with. The responsible director must have real law will also have some other modifications, such possibilities to take effectively care of this duty. as extending the claiming period up to 30 years STUK’s Guide YVL 1.4 sets general require- for victims of nuclear accidents. As the interna- ments for management systems. An updated guide tional ratification of the 2004 Protocols has been YVL A.3 concerning the management systems is delayed, Finland made a temporary amendment in under development and will be implemented dur- the Finnish Nuclear Liability Act in 2012, imple- ing 2013-2014. The new YVL A.3 is also based on menting the provision on unlimited liability and IAEA GS-R-3, and it includes even more detailed requirement of insurance coverage for a minimum requirements for promoting good safety culture amount of EUR 700 million. The temporary law than the current guide YVL 1.4. The management came into force in January 2012 and will be re- system must support the characteristics of the or- pealed when the 2005 law amendment takes effect ganisational culture that promote good safety cul- after the international ratification of the Paris and ture, and the management must express its com- Brussels Conventions. mitment to safety. Safety culture expertise must be In conclusion, Finnish regulations and practices available for developing the safety culture. The de- are in compliance with Article 9. velopment of the safety culture must be target ori- ented and systematic. The procedures used must Article 10. Priority to safety strengthen a vigilant, questioning and initiative Each Contracting Party shall take the appro- attitude at all levels of the organisation. The man- priate steps to ensure that all organizations agement system must also contain procedures for engaged in activities directly related to nucle- identification and continuous promotion of safety ar installations shall establish policies that culture. The licensee has to also establish a process give due priority to nuclear safety. to measure, assess and improve its’ safety culture. STUK is also developing a new YVL guide Regulatory requirements regarding concerning nuclear facility construction and modi- safety culture and safety management fications, i.e., YVL A.5. Also in this guide there are The importance of a good safety culture is em- requirements concerning safety culture and risk phasised in the Nuclear Energy Act and in the management. During construction and modifica- Government Decree on the Safety of Nuclear Power tions the licensee must ensure that the contribut- Plants (733/2008, Sections 21, 28 and 29), which ing parties are able to perform according to safety state that when designing, constructing, operat- requirements and there must be training on safety ing and decommissioning a nuclear power plant, a culture issues for the personnel taking part in the good safety culture must be maintained by making activities. The licensee must have procedures for sure that the decisions and activities of the entire evaluating and developing the safety culture of the organisation reflect commitment to safety. Licensee contributing parties. Guide YVL A.5 is planned to has to ensure that these requirements are applied be published in 2013 and implemented at the exist- in all organisations that participate in safety sig- ing nuclear power plants or plants under construc- nificant activities. An open working atmosphere tion in 2013-2014. The new guide is applied as such must be promoted to encourage identification, re- to new nuclear facilities. porting and elimination of factors endangering TEPCO Fukushima Dai-ichi accident has high- safety, and the personnel must be given opportuni- lighted the importance of safety culture and its ty to contribute to the continuous enhancement of continuous assessment and improvement. The safety. According to the Nuclear Energy Act, a re- Diet report in 2012 concluded that “fundamen- sponsible director has to be appointed for the con- tal causes of the accident are to be found in the

30 Article 10 – Priority to safety STUK-B 164 ingrained conventions of Japanese culture; our Fortum has continued the special training pro- reflexive obedience; our reluctance to question au- gramme for the Loviisa NPP contractors, with thority; our devotion to ‘sticking with the program’; which the licensee aims to ensure the right at- our groupism; and our insularity”. These ingrained titudes and safety culture among the contractors conventions were seen as factors preventing nec- working at the NPP. In the training, Fortum com- essary stakeholders (Licensee, Regulatory Body municates the safety-first-principle and nuclear and Government) to take needed actions to ensure and radiation safety issues for contractor person- safety and therefore also contradicting with good nel working at the site. The contractor training safety culture. The influence of ingrained conven- is valid only for a determined time and has to be tions in national culture is considered in Finland repeated when expired. All contractors and suppli- to be one of the key messages in the Diet report. ers are regularly evaluated by Fortum to ensure To better understand the ingrained conventions in that they can fulfil the regulatory and safety re- the Finnish culture and their possible positive and/ quirements. Fortum has developed procedures for or negative impacts on safety culture, STUK has ensuring appropriate competence for the auditors made a decision to conduct a research in the near conducting contractor evaluations and audits. future. Olkiluoto NPP Measures taken by licence holders The Olkiluoto NPP has worked several years with safety culture evaluation and development. The Loviisa NPP operator TVO has founded a special safety cul- Fortum Nuclear Competence Center consists of ture team that is independent from operations and Loviisa NPP, Technical Support and the Nuclear construction. This team meets regularly about 10 Safety Oversight (NSO). NSO oversees the Fortum times a year and the mission is to form a compre- Nuclear operations and Loviisa NPP, is independ- hensive view of the safety culture situation in the ent from operations and reports to the licensee whole TVO and report and give suggestions to the management. Loviisa NPP has made organisation- top management of the organisation. The NPP has al changes that aim at also promoting the safety had a safety culture specialist available who has culture development. There is a unit especially facilitated the safety culture self evaluations and dedicated for operational experience and safety also implementations of different safety culture culture. In addition, the Loviisa NPP has an inde- promoting methods. An example is the Human pendent advisory body for safety issues, i.e., a nu- Performance Improvement program including peer clear safety committee with external expert mem- checking, two way communication etc. bers. Fortum has established documented quality TVO has also an independent cross functional and safety policies for the Loviisa NPP. safety group that consists of specialists among Fortum has continued having international NPP’s own staff and also external expert members evaluations of safety management and procedures that are called in for special topics. at the Loviisa NPP in order to improve its own TVO has assessed the safety culture of the operations. IAEA carried out an OSART safety Olkiluoto NPP through several methods. The safe- review in Loviisa in March 2007, with a follow-up ty culture issues have been regularly discussed in review in July 2008. WANO peer review was per- the safety group meetings. The self-assessment is formed in March 2010, with a follow-up review in repeated approximately every third year. Personnel April 2012. In the latest WANO follow-up review, surveys and the peer review method of the World WANO stated that most development actions were Association of Nuclear Operators (WANO) have completed where as a couple of them are still in also been utilised actively. TVO has also docu- progress, although they have been appropriately mented quality and safety policies for the Olkiluoto started. NPP and so called ‘Management Expectations’ fly- Loviisa NPP has conducted a safety culture self ers, where the managers communicate very clearly evaluation according to a renewed procedure dur- their expectations for safe working and safety at- ing 2012. Based on the results from the evaluation titudes. Loviisa NPP has formed an action plan.

31 STUK-B 164 Article 10 – Priority to safety

TVO has continued using and developing the plants and the regulatory body. safety culture promotion and assessment methods In the end of 2010 and beginning of 2011, STUK concerning the Olkiluoto unit 3 project and the conducted an event investigation concerning the contributing parties. Assessment method consists Olkiluoto NPP unit 3 Emergency Diesel Generator of a questionnaire, interviews and analysis of procurement. The investigation underlined the safety observations, authority inspections and non- importance of strict supply chain management conformance records. The Safety Culture report is especially stressing the safety requirements and prepared twice a year. Safety culture promotion the communication of these during the whole pro- methods include safety culture pilots, info tv and curement and delivery process and to all involved materials, regular safety culture meetings with the parties. The importance of the management’s lead supplier and so on. A strong safety culture is also in enhancing safety culture and priority to safety essential during the commissioning phase, which was also recognised and unility’s attitude was also has been taken into account in cooperation with crucial in communication with all stake-holders. the commissioning personnel. STUK has developed a special inspection tool TVO administrates and follows up the compe- for gathering information about issues related to tence of contractors that work at the plant regu- Human and Organisational Factors (HOF) within larly or for longer terms. These contractors have periodic inspection programme for operating NPPs. to complete the same basic training as NPP’s own The tool was implemented during 2012. Based on personnel as appropriate. Basic nuclear and radia- the findings according to four predefined areas, tion safety training is prerequisite for all persons i.e. personnel planning, communication, handling working at the site. Priority to safety is addressed of non-conformances and process management, in the training. TVO regularly audits and evalu- STUK can obtain an overall picture of the li- ates contractors and suppliers to ensure that they censee’s situation concerning these HOF topics. can fulfil the regulatory and safety requirements. STUK developed also in 2012 a special database for collecting HOF related findings made during Regulatory oversight the oversight of the Olkiluoto NPP unit 3. The STUK has continued to regularly inspect the man- IRRS mission team suggested that STUK should agement systems of both licensees (Fortum and consider the development and implementation of a TVO) to ensure that they are fulfilling the require- more systematic method for collection and assess- ments of the legislations and the Guide YVL 1.4. ment of indications of the licensee’s safety culture. Based on the inspections, there is still need for STUK will continue developing the collection and development actions to fulfil the requirements es- analysis of all HOF related findings by expanding pecially concerning the process based management the database for both operating NPPs and NPPs and supply chain management. The safety culture under construction. is also included as a topic in the STUK’s periodic STUK co-operates with VTT Technical Research inspection programme. During 2010–2013 the in- Centre of Finland on safety culture related inspec- spections have dealt with especially safety culture tions and VTT is conducting a re-assessment on evaluation methods and management commitment safety culture at the Olkiluoto unit 3 construction for safety culture and the responsibility for the site. Safety culture related seminars have also management to define and communicate the re- been arranged together with both VTT and the quirement for a good safety culture. There is a spe- licensees, and vendors. cial top level inspection in the periodic inspection programme, “Management and Safety Culture”, Means used by regulatory body that includes an assessment of safety culture is- in its own activities sues, management and leadership. Additionally, Safety is emphasised in the Quality Manuals of safety culture issues are included in quality as- STUK as well as in the framework contract be- surance audits and event analyses. Safety culture tween STUK and its technical support organisa- related findings from different inspections are tion VTT Technical Research Centre of Finland. discussed in regular meetings in STUK and be- STUK’s Quality Policy includes STUK’s values tween the senior management of the nuclear power that give the highest priority to keeping the ra-

32 STUK-B 164 diation exposure of people as low as reasonably Financial resources achievable and preventing radiation and nuclear Nuclear Energy Act defines as a condition for accidents. STUK has taken an active role in this granting a Construction or Operating Licence that area and both developed its own culture and taken the applicant has sufficient financial resources, the initiative in the assessment of cultures of the necessary expertise and, in particular, that the op- licensee organisations. The IRRS mission was car- erating organisation and the competence of the ried out in fall 2012 and the reviewers suggested operating staff are appropriate. According to the that STUK could emphasise safety culture also in Nuclear Energy Act, the licensee shall also have its quality manual in a more detailed way as well adequate financial resources to take care of the as to assure the safety consciousness of the staff. safety of the plant. In addition, Nuclear Energy Act To meet this suggestion, STUK decided to update provides detailed regulations for the financial ar- its management system and to include self-assess- rangements for taking care of nuclear waste man- ment of safety culture into annual self-assessment agement. The Act on Third Party Liability provides programme. regulations on financial arrangements for nuclear Both the periodic inspection programme and accidents, taking into account that Finland is a the construction inspection programme are es- party to the Paris and Brussels conventions. tablished according to STUK’s strategic decisions The financial preconditions are primarily as- about safety critical areas at NPPs. These ar- sessed by authorities other than STUK (mainly eas are covered at least every third year at the the Ministry of Employment and the Economy). operating nuclear power plants. STUK conducts The financial position and business environment self-assessments and personnel questionnaires to of the licensee also affect the safety of plants, and follow up the internal opinions regarding the pri- STUK therefore follows licensees’ plans to improve ority devoted to different topics of nuclear safety. safety of nuclear power plants, as well as organi- STUK arranges regularly training for the inspec- sational reforms, safety research conducted by tors and an introduction programme is set up for licensees, the number of employees and the compe- all new recruited inspectors. STUK has added tence of personnel. The annual reports of Fortum resources to and reorganised the organisation that Corporation and Teollisuuden Voima Oyj provide handles NPP security issues. Similarly STUK has financial information on the utilities. Both utilities strengthened its personal resources for the review have annually invested typically about 40–50 M€ of the construction licence application submitted for maintaining the plant and improving safety. by Posiva Oy at the end of 2012 for the spent fuel For example, TVO has recently made a decision to encapsulation and disposal facility in Olkiluoto. renew all emergency diesel generators where the In conclusion, Finnish regulations and practices overall investment is more than 100 M€. are in compliance with Article 10. A financing system for the costs of future waste management and decommissioning exists to en- Article 11. Financial and sure that the producers of nuclear waste bear their human resources full financial liability on the coverage of those costs 1. Each Contracting Party shall take the ap- and that the costs can be covered even in case of propriate steps to ensure that adequate insolvency of the waste generator. The pertinent financial resources are available to sup- licence-holders submit every three years for regu- port the safety of each nuclear installation latory review the technical plans and cost calcula- throughout its life. tions on which the liability estimates are based. 2. Each Contracting Party shall take the ap- After confirmation of the financial liabilities, the propriate steps to ensure that sufficient licensees pay fees to a State controlled Nuclear numbers of qualified staff with appropri- Waste Management Fund and provide securities ate education, training and retraining are for the liability not yet covered by the funded available for all safety-related activities in money. At the end of 2012, the funded money or for each nuclear installation, through- (2 160 million euros) covered most part of whole out its life. liability (2 238 million euros). Under the Nuclear

33 STUK-B 164 Article 11 – Financial and human resources

Energy Act, nuclear companies should supplement bility for developing the specialist competence lies the fund by payment of 83 million euros in early on the line organisation. The training unit’s main April 2013. responsibility is to develop the human resource management procedures and organise the general Human resources training sessions. The training organisation has The licensee has the prime responsibility for ensur- been strengthened with experts in behavioural ing that all the employees are qualified and author- sciences. Fortum has a procedure for setting up in- ised to their jobs. The regulatory requirements for dividual development plans for all newcomers and human resources are stated in the Nuclear Energy for persons changing positions. Fortum has defined Act (Sections 7 and 20), the Government Decree on the qualification needs for the different positions the Safety of Nuclear Power Plants (733/2008) and based on job descriptions, but the challenge is to STUK’s Guides YVL 1.6 and YVL 1.7. The Nuclear break down the descriptions to real competencies Energy Act Section 7 was modified during 2012 and development needs. Loviisa NPP has to devel- with a demand to appoint also deputies for the op more its strategic competence management to responsible persons for emergency preparedness, be able to ensure the resources needed for a longer security and safeguards. According to Section 30 term. STUK has by inspections identified a need of the Government Decree 733/2008, significant for human resource development in, for example, functions with respect to safety within nuclear quality assurance. Loviisa NPP has during 2012 power plants must be designated, and training pro- recruited some full time project managers and grammes must be prepared for development and increased the quality management training to im- maintenance of professional qualifications of the prove the situation. Fortum has a full scope simu- persons working in these positions. Adequate com- lator at the Loviisa NPP to ensure the training of mand of the functions in question must also be operators. Fortum takes actively part in developing verified. The Guide YVL 1.6 sets requirements for and executing the national nuclear safety training NPP operator competence, and the Guide YVL 1.7 (YK) course to ensure competence for the nuclear for training and qualifications of personnel work- field now but also in the coming years. ing in functions that are important for plant safety. TVO has updated the personnel plan regu- The YVL Guides concerning human resources are larly according to the phases of Olkiluoto NPP currently being updated and will be replaced by unit 3 construction phase and also considering the guide YVL A.4 during 2013. This new YVL the planning of the fourth reactor Olkiluoto unit guide has more specific requirements for safety 4, for which TVO got the Government Decision in critical positions, e.g. for responsible director and Principle in 2010. TVO has also started a trainee persons responsible for safeguards, emergency pre- program for developing young recruits for a career paredness and security. The guide also has specific at TVO. TVO has also during 2012 actively started requirements on management and leadership com- to seek solutions for planning resources efficiently petencies. between projects and day to day operations. The Human resource planning at the Loviisa NPP ageing power plants and the more demanding is based on a ten-year plan, which is subject to an- safety requirements need more and more improve- nual management review and updating. Loviisa ment projects with critical time schedules. An effi- NPP has taken into use a project management cient plant modification and project procedure is of procedure which includes a resource management high importance for safe and successful operations. approach that will support the NPP in evaluating TVO has revised their training program and proce- and following up the resources needed for accom- dures taking into account the commissioning of the plishing the projects. Olkiluoto unit 3 and the increasing need for sys- The training activities and procedures at the tematic and strategic competence management due Loviisa NPP are constantly developing. Much re- to the growing organisation (OL3, OL4). TVO uses sponsibility is given to the line manager and the an IT-system that supports the managers e.g. in individual defining of qualification and training defining and following up individual development needs. The training unit can support the line or- plans. TVO has defined training requirements for ganisation with their expertise, but the responsi- each position or job that automatically will be in-

34 Article 11 – Financial and human resources STUK-B 164 cluded in the new recruited person’s development Aalto University and Lappeenranta University plan. In 2010 TVO had a WANO Technical Support of Technology, Ministry of Employment and the Mission that gave TVO good bench-marking input Economy). for the development actions. During 2010–2012 a committee set up by the Personnel and human resources related issues Ministry of Employment and the Economy worked are included in STUK’s periodic and construc- on a report aiming at giving recommendations tion inspection programmes at the nuclear pow- and steps to be taken until the 2020’s for ensuring er plants. A top level inspection of the periodic competence and resources needed for the nuclear inspection programme, “Human Resources and sector. STUK was an active part in this commit- Competence”, includes assessment of human re- tee. One of the recommendations of the committee source management, competence development and was: The future needs and focus areas of Finnish training programmes. It also covers the licensee’s nuclear energy sector research must be accurately procedures for managing human resources and defined and a long-term strategy drawn up for competence of suppliers, sub-suppliers and other further development of research activities. This partners participating in functions affecting safety. calls for a separate joint project among research During the years 2010–2013 STUK has paid atten- organisations and other stakeholders in the field. tion especially to personnel planning and ensuring The report can be found on http://www.TEM.fi/ resources in development and modification pro- files/33099/TEMjul_14_2012_web.pdf. jects. STUK also participates in examinations of At the end of January 2013 the Ministry of shift personnel, where the operators working in the Employment and the Economy set up a working control rooms show that they are conversant with group to prepare a research and development all salient matters related to plant operation and strategy. The objectives of the working group in- safety. STUK further approves the appointment clude the following tasks: (1) definition of main de- of certain key personnel, such as the responsible velopment lines for the Finnish research activities director and his/her deputies. in the area of nuclear energy (vision until 2030, Ensuring an adequate national supply of ex- road maps, nuclear energy research in general, perts in nuclear science and technology and high nuclear safety research, research on advanced nu- quality research infrastructure is recognised as clear reactor concepts, research on nuclear fusion a continuous challenge in Finland because of the technology), (2) identification of priority areas for retirement of large age groups, ongoing Olkiluoto nuclear energy research taking into account fu- unit 3 construction project and the new reactors, ture research needs and the required knowledge that got the government Decision in Principle in base, (3) definition of the needs for the develop- May 2010. In addition to the measures to maintain ment of research infrastructure covering the needs and develop the capabilities and amount of profes- of different actors in the nuclear energy sector, sional staff of STUK and the utilities, the similar (4) optimization of the management of national requirements for maintaining and developing the research programmes as well as the provision of human resources in the nuclear energy sector ap- funding to the research programmes and (5) enable ply to VTT Technical Research Centre of Finland, more significant than presently participation of which acts as the main technical support organisa- Finland in the international research activities in tion to STUK. In the same way one has to devote the nuclear energy sector. The working group will appropriate measures to develop the educational be chaired by a representative of the Ministry of resources in technical universities and other high- Employment and the Economy. The Ministry will level universities in Finland. also provide secretariat to the working group. The The main organisations in the nuclear energy nominated members of the working group include area develop and organise the basic professional experts from STUK, VTT, Finnish Academy, Aalto training course on nuclear safety, which is a yearly University, Technical University of Lappeenranta, held approximately 5-week training programme University of Helsinki, Fortum, TVO and Posiva. for students and staff members of the partici- In conclusion, Finnish regulations and practices pating organisations (STUK, the licensees, VTT, are in compliance with Article 11.

35 STUK-B 164

Article 12. Human factors ment of operating procedures. Large part of plant’s Each Contracting party shall take the appro- emergency operating procedures (EOPs) have been priate steps to ensure that the capabilities modified into flowchart format. These EOPs in- and limitations of human performance are clude symptom based identification which guides taken into account throughout the life of a operators to event based procedures. Complex ac- nuclear installation. cident sequences and core melt accidents lead to symptom based operation. Human redundancy is Regulatory requirements provided by independent on-duty safety engineer. regarding human factors These emergency operating procedures have gone Human reliability in the plant operations is large- through a comprehensive set of verification and ly based on good plant design and proper pro- validation activities which include background cedures and training. According to Section 6 of analysis of the plant behaviour. Loviisa plant the Government Decree on the Safety of Nuclear is equipped with a full scope training simulator Power Plants (733/2008), special attention must be which is used for operator training, including ac- paid to the avoidance, detection and correction of cident situations. any human error during design, construction, op- Fortum evaluates human reliability as part of eration and maintenance. The possibility of human the probabilistic risk assessment (PRA). For ana- errors shall be taken into account in the design of lysing hidden defects influencing the course of a a nuclear power plant and in the planning of its possible transient or accident, Fortum has evalu- operation and maintenance, so that human errors ated regularly different types of duties performed and deviations from normal plant operations due at the plant. In the analysis such operational and to human error do not endanger plant safety. The maintenance mistakes have been evaluated which impacts of human error shall be reduced by us- may act as an initiating event of a transient or an ing various safety principles, including defence-in- accident. Different plant states and duties related depth, redundancy, diversity and separation. to them have been evaluated in detail. According to Section 19 of the Government Control actions needed during an accident have Decree 733/2008, the control rooms of a nuclear been divided in the PRA evaluation into two parts: power plant must contain equipment that provides a diagnosis and actions taken to prevent the ac- information on the operational state of the nuclear cident. Possibilities for mistakes have been studied reactor and any deviations from normal operation. with the help of a simulator. Plant procedures for Furthermore, the nuclear power plant shall con- emergency situations have been developed and will tain automatic systems that actuate safety func- be further developed, taking also into account the tions whenever required and control and supervise results of PRA. For preventing human errors it is their functioning during operational occurrences important, that the operating events are carefully and accidents. These automatic systems shall be evaluated and, if necessary, procedures of the nu- capable of maintaining the plant in a controlled clear power plant are developed to prevent similar state long enough to provide the operators with mistakes. Fortum has developed the utilisation of sufficient time to consider and implement the cor- operating experiences and conducts the root cause rect actions. The nuclear power plant shall have an analyses out of most significant events. emergency control room independent of the control The protection systems of the plant initiate the room, and the necessary local control systems for safety systems automatically when needed so that shutting down and cooling the nuclear reactor, and the operators will have enough time to consider for removing residual heat from the nuclear reac- actions according to operating and emergency pro- tor and spent fuel stored at the plant. cedures. Due to the inherent characteristics of the Loviisa plant, the operators will have more time for Measures taken by licence holders consideration in a transient situation than usually at other nuclear power plants. The Loviisa units Loviisa nuclear power plant 1 and 2 have their own independent main control Measures at the Loviisa plant to ensure adequate rooms where the needed process information is human performance have been focused on develop- available and control actions can be performed.

36 Article 12 – Human factors STUK-B 164

Alarm signals from the interim spent fuel stor- trol rooms are based on the proven control room age are also available in the Loviisa unit 2 main technology. During the renewal of turbine automa- control room. Process information is presented tion system several new computerised operator in the main control room with indicating meters, workstations and a large screen display system indicator lights and recorders as well as with the were installed into the main control room. Process monitors of the process computer system. There information is presented by the indicating measur- are two redundant alarm systems in the main ing equipment installed in the steering desks and control room. These systems have been realised by panels as well as with several computer display using two different techniques, conventional and units. Conventional and computer aided alarm computer-based techniques. Indicator light fields systems are used to facilitate the management of are on the operator’s consoles, and two monitors main processes and other sub and auxiliary pro- have been reserved for computer alarms. In addi- cesses. The alarms are indicated primarily by the tion, data on events and conditions as well as the alarm lamp panels. The parallel alarms received exceeding of warning and alarm limits are record- through the computer are seen on the monitors. ed by the alarm printers. The process computer In addition, the event and state data as well as gives process information in an illustrative format deviations from warning/alarm limits are printed for the use of the operators. on the alarm printers. A safety parameter display In addition to the main control room, the shut- system (SPDS), which improves the performance down of the reactor as well as the control and capability of the operating personnel in controlling monitoring actions necessary for safety can be per- transient and accident situations, is in use at the formed by means of a so-called emergency control Olkiluoto plant units. Main control room can now room table, located in the main control room of the be described as a hybrid control room. All the main other unit. For severe accidents there is a separate control room related modifications are tested at the dedicated control room shared by both units. training simulator, and operators are trained for The I&C systems are currently being renewed managing the modified systems prior to the modifi- at the Loviisa plant. Human performance is taken cations are installed. into account in the modification. This automation Both Olkiluoto plant units have an emergency renewal project has a dedicated control room de- control post, from where the reactor can be tripped sign team, which is in charge of the human factors and where the main parameters of the reactor such engineering (HFE). as neutron flux, pressure, temperature and water level can be monitored. Cooling the reactor down to Olkiluoto nuclear power plant a cold state and removal of decay heat can be car- Basis for safe operation is laid already in design ried out after the shutdown by using local control phase. A so-called 30-minute rule has been the de- posts. The requirement of another, independent sign basis for the protection system at the Olkiluoto emergency control room emerged after the revision units 1 and 2. Important protection measures and of the STUK’s Guide YVL 5.5 “Instrumentation safety systems start up automatically so, that no systems and components at nuclear facilities” in actions of operating personnel are needed dur- 2002. TVO is evaluating possibilities to improve ing the first thirty minutes after the beginning of and centralise the emergency controls to better the operational transient or postulated accident. comply the present requirements. Modifications Proper emergency and transient situation proce- are currently under detailed design. dures as well as training for those situations re- There are methods for preventing human errors duce the possibility of human errors further. during operation. Main areas to be considered are Olkiluoto units 1 and 2 have their own in- operation, maintenance and modification projects. dependent control rooms, where the necessary Human reliability can be enhanced in every day process information is available, and from where activities with certain methods. These methods all necessary control measures can be conducted. include pre-job-briefing, de-briefing, peer checking, The alarms covering the interim spent fuel storage independent verification and clear communication. are available in the control room of the Olkiluoto TVO has trained and introduced these methods unit 1. The technical solutions of the main con- in feasible activities. Proper work planning and

37 STUK-B 164 Article 12 – Human factors

Permit-to-Work-system in addition to up-to-date in order to identify any previously unnoticed er- procedures are key methods in maintenance relat- rors. Some clarifications have been made into ed activities to ensure safety during maintenance. procedures based on these talk/walk-throughs and Checking and approval requirements are also con- simulator tests. sidered when requalifying systems back into oper- For the Olkiluoto unit 3, human factors engi- ation. This work is part of a company wide project neering has been part of the design phase. Concept called “Human Performance 2012” which incor- of operation is taken from existing units and ref- porates also other measures to improve human erence plants. Main control room has operational performance. The aim is to support managers and I&C system with operating terminals and large the personnel in managing human performance to screen displays. This interface can be used in all avoid as many human mistakes as possible. plant conditions. Additional information can be Human Factor issues are taken into account integrated into this system, e.g. alarm systems and in all events. Lessons learned from the events are operating procedures. Safety related I&C system taken into account in the corrective action plans has own traditional operating panels which are and lessons learned are used in internal training diverse control method for operational I&C. These and organisational development. TVO has utilised safety panels include also hardwired controls operating experience and results of root cause which are additional back-up for all I&C systems. analyses in the development of human aspects in Olkiluoto unit 3 has also remote shutdown sta- the operating procedures. Errors related to the tion. Feasibilty of human factors engineering will maintenance actions have also been examined be demonstrated in validation studies. Integrated and measures have been developed to avoid corre- validation will be done at a full scope simulator sponding errors. Fatigue has been identified as an before plant commissioning. important factor to be managed. TVO has conducted a probabilistic risk assess- Regulatory oversight ment (PRA) where the consequences of human Human factors have to be taken into account in errors have been studied. Latent maintenance and the design and analysed in the failure analyses of testing errors have been studied in connection with plant safety systems and in probabilistic risk as- the system analyses related to the PRA. In addi- sessments. Such analyses have been completed for tion to the human factor experts, experienced staff both Finnish nuclear power plants. In addition to members from the operating and maintenance this high level licensing documentation, individu- personnel have participated in assessing the pos- al system design needs to be reviewed by STUK. sibility of errors. The identified error possibilities Main emphasis is on the control room design ap- have been classified into groups according to their provals. Design documentation needs to reflect importance and the most important ones have proper human factors design and design shall be been modelled in the PRA study to clarify the coordinated with quality plans, change processes risks related to errors. The reliability of operator and verification/validation plans. Finally licensee actions conducted during accident conditions was shall demonstrate the safety with integrated sys- assessed as a part of the PRA analysis. The diag- tem validation and analyse the results. Human er- nostic errors that may be made in connection with ror discrepancies need to be addressed if there are accidents have also been assessed. Based on the major findings, before commissioning of the control results of the analyses concerning the human er- room systems can proceed. rors, a few additions and modifications have been In conclusion, Finnish regulations and practices made on the emergency and operating procedures are in compliance with Article 12. of the Olkiluoto units 1 and 2. Emergency operat- ing procedures have been recently re-evaluated

38 STUK-B 164

Article 13. Quality assurance Measures taken by licence holders Each Contracting Party shall take the appro- priate steps to ensure that quality assurance Loviisa nuclear power plant programmes are established and implemented Fortum’s Policy Commitment to Quality in the with a view to providing confidence that spec- Nuclear Power Operations was revised and con- ified requirements for all activities important firmed by the management of Fortum in 2010. The to nuclear safety are satisfied throughout the development of Loviisa NPP’s quality management life of a nuclear installation. system is based on the principle of continuous im- provement in accordance with the observations Regulatory requirements regarding and remarks made in quality audits and quality management systems assessments. The environmental management sys- According to Section 29 of the Government Decree tem of the plant was certified in 2002 according to on the Safety of Nuclear Power Plants (733/2008), the ISO 14001:1996 standard. During the prepa- the organisations participating in the design, con- ration phase an environmental policy and a new struction, operation, and decommissioning of a nu- chapter on environmental system were introduced clear power plant are required to employ a man- in the Quality Manual. agement system. The quality management system Fortum has developed their management sys- must cover all functions influencing plant safety, tem, according to the Guide YVL 1.4 requirements. and the licensees are further required to ensure The quality management system of Fortum Power that all their suppliers, sub-suppliers and other & Heat Oy for the Loviisa NPP complies with the partners participating in functions that affect nu- requirements of the Guide YVL 1.4 in most re- clear and radiation safety adhere to the quality spects, but some deviations still remain of which management system. Along with the management the most significant is the lack of process based system, the Decree sets requirements for the docu- management approach. Fortum applied in 2012 for mentation of the lines of management and moni- a deviation from the requirements of the process toring of the operations. management but STUK made an assessment that STUK’s Guide YVL 1.4 sets general require- Loviisa NPP has already made progress on the ments for management systems. An updated Guide path towards a process based management sys- YVL A.3 concerning the management system is tem and that this development shall be continued. under development and will be published in 2013. Another area where deviations exist is the sup- Guide YVL A.3 adheres to IAEA Safety Standard plier management. Fortum conducted an independ- GS-R-3 on management systems. Requirements for ent evaluation of the purchasing activities at the the quality assurance programme during operation Loviisa NPP in the end of 2012 and this evaluation are presented in the Guide YVL 1.9 and require- will result in a development program for year 2013 ments for quality management of system design with licensee top management strong commitment. in the Guide YVL 2.0. The quality management Loviisa NPP has clearly defined the responsibili- requirements related to specific technical areas are ties for developing the management system and presented in the corresponding technical guides. reformed the management procedures for review- STUK is also developing a new YVL guide concern- ing the management system. Loviisa NPP has ing nuclear facility construction and modifications, had special training sessions for defined personnel i.e., YVL A.5. In this new guide, there are require- on the topic management system and the Guide ments for example on supplier management. The YVL 1.4. Loviisa has reformed also the quality as- management systems of the licensees and appli- surance (QA) personnel qualification demands and cants are subject to approval by STUK. According procedures for evaluating and developing the QA- to the Guide YVL 1.4, any safety-significant revi- competence. sions to the management system must be submit- ted for approval to STUK, but minor revisions are Olkiluoto nuclear power plant only submitted for information prior to their use. TVO’s quality management system is described in the Quality Management Manual. It takes into account the requirements from YVL 1.4, IAEA

39 STUK-B 164 Article 13 – Quality assurance

GS-R-3 and ISO 9001:2000. TVO is actively de- the process management, quality assurance com- veloping the management system towards a pro- petence in procurement and supply management. cess based management system due to the grow- The management systems of the main suppliers ing organisation and the need for systematic and are also reviewed and assessed and their imple- efficient operations throughout the organisation. mentation is verified through inspections and au- The Management System guides all TVO’s opera- dits mainly by the licensee where STUK is taking tions and provides each staff member with proce- part as an observer. dures for the safe, economical, high-quality and Concerning the Olkiluoto unit 3 construction environmentally friendly generation of electricity. project, STUK has performed quality management TVO’s company-level policies are nuclear safety and quality assurance inspections as a part of the and quality policy, social responsibility policy, pro- construction inspection programme. In addition, duction policy and corporate security policy. The STUK has participated as an observer in the licen- functions and responsibilities of TVO’s organisa- see’s and vendor’s quality audits at the subcontrac- tions and personnel are described in detail in the tors. STUK’s inspections have been focussed on TVO’s Administrative Rules, in the Organisational the forthcoming integration of the management Manual and in the manuals and instructions of system of Olkiluoto unit 3 to TVO’s management individual organisational units. For the Olkiluoto system during commissioning phase. unit 3 construction phase, STUK has approved During 2012 STUK had an external consultant “The Quality Manual for Olkiluoto 3 Project”. The evaluating the licensees’ procurement and supply review of document as well as review of the QM management procedures and instructions to get an systems of plant vendor and major suppliers is car- independent specialist opinion about the maturity ried out by STUK. STUK has also asked external of the procedures. QM experts’ opinions on the QM systems. The quality management system of TVO for Management system of the regulatory body the Olkiluoto units 1 and 2 mainly complies with STUK has an own Quality Manual that includes the requirements of the Guide YVL 1.4. The most quality policy, description of the quality system, significant development need concerns the process organisation and management, main and support- management and process descriptions. TVO also ing working processes and personnel policy. The needs to develop the purchasing processes and the results of internal audits, self-assessments and in- quality assurance competence in procurement. The ternational evaluations are used as inputs for the lessons learned from the Olkiluoto unit 3 emer- enhancement projects of the Quality Management gency diesel generator event investigation were to System at STUK. In addition to STUK’s Quality be applied to Olkiluoto units 1, 2 and 3 (see Article Manual, all main functions of STUK have their 10). According to STUK’s review, the management own more detailed Quality Manuals. system of Olkiluoto unit 3 complies with the Guide STUK’s management system will be further YVL 1.4. developed during the next years according to the suggestions of the IRRS mission. For example, Regulatory oversight STUK will review and revise the existing Quality STUK has followed up the implementation of the Manuals and guidance documents for consistency YVL 1.4 requirements in the management sys- and improve overall descriptions of the processes tems of the licensees during the periodic inspection including sub-processes and their interdepend- program. The top level inspection of the STUK’s ency. STUK will also develop further a systematic periodic inspection programme, “Functioning of long-term programme for self-assessments, inter- the Management System”, includes assessment nal and external audits and evaluations on the of functioning, development and assessment of effectiveness of the processes. In addition, STUK the management system as well as assessment will develop more detailed procedures for the use of the organisation for quality management. The of graded approach in the authorisation of systems, “Management and Safety Culture” inspection (see structures and components and in the planning Article 10) also contains items concerning man- and conducting inspections. agement systems. During 2010–2013 the manage- In conclusion, Finnish regulations and practices ment system inspections have especially dealt with are in compliance with Article 13. 40 STUK-B 164

Article 14. Assessment and sification document, the quality management pro- verification of safety gramme for the operation of the nuclear facility, Each Contracting Party shall take the appro- Operational Limits and Conditions, a programme priate steps to ensure that: for periodic inspections, security and emergency i. comprehensive and systematic safety as- plans, a description on administrative rules for sessments are carried out before the con- safeguards, a programme for radiation monitoring struction and commissioning of a nuclear in the environment of the nuclear facility, a de- installation and throughout its life. Such scription of how safety requirements are met, and assessments shall be well documented, sub- a programme for the management of ageing. In ad- sequently updated in the light of operating dition, the Decree gives STUK a possibility to ask experience and significant new safety in- other documents considered necessary for safety formation, and reviewed under the author- demonstration. ity of the regulatory body; Design of the facility is described in the ii. verification by analysis, surveillance, test- Preliminary (PSAR) and Final (FSAR) Safety ing and inspection is carried out to ensure Analysis Reports. The reports are submitted that the physical state and the operation to STUK for approval with the applications for of a nuclear installation continue to be Construction and Operating Licences. PSAR/FSAR in accordance with its design, applicable forms the basis to STUK’s safety assessment which national safety requirements, and opera- is required before granting the Construction/ tional limits and conditions. Operation Licence (see Article 7). According to the Nuclear Energy Decree, FSAR has to be continu- Regulatory approach to safety assessment ously updated, and changes to FSAR have to be The prerequisite of the Construction and Operating submitted to STUK for approval. Requirements Licences is that the licence applicant has made its for the plant modification process are presented own safety assessment. The fulfilment of the safety in the Guide YVL 2.0, “Systems design for nuclear requirements is demonstrated in the Construction power plants”. The main principle in plant modifi- and Operating Licence documentation. STUK cation process is that conceptual design plans and makes an independent safety assessment concern- system-specific pre-inspection documents of Safety ing the application and this assessment is required Class 1, 2 and 3 systems must be submitted to in the Nuclear Energy Act. Conditions for granting STUK for approval. STUK reviews and approves a Licence are provided in the Nuclear Energy Act. the modification prior to its implementation at the For example, there is a requirement that the use of plant. In connection with a system modification, nuclear energy must be safe. In Section 20 of the the Final Safety Analysis Report shall be amended Act it is further stated that the operation of the accordingly without delay. nuclear facility shall not be started until STUK The general design bases for nuclear fuel have has ascertained that the nuclear facility meets the been defined in the Guides YVL 1.0 and YVL 6.2. prescribed safety requirements. The design objective is that the probability of fuel The Nuclear Energy Decree requires that when failure is low during normal operational condi- applying for a construction licence, the applicant tions and anticipated operational transients, and must submit to STUK the following documents: that during a postulated accident the rate of fuel a Preliminary Safety Analysis Report, a design failures remains low and the fuel remains in a cool- phase Probabilistic Risk Assessment, a proposal able state. Detailed requirements for the design, for a safety classification document, a description quality management and control, handling, storage of Quality Management during the construction of and transport of fuel are specified in the Guides the nuclear facility, preliminary plans for the ar- YVL 6.2, YVL 6.3, YVL 6.4, YVL 6.5, YVL 6.7 and rangements for security and emergency prepared- YVL 6.8. ness, and a plan for arranging the safeguards con- According to the Nuclear Energy Act, the oper- trol. For the operating licence, the applicant must ating licence is granted for a fixed term. However, submit to STUK: the Final Safety Analysis Report, legislation has not prescribed the length of the the Probabilistic Risk Assessment, the safety clas- term. The term is proposed by the licensee in the

41 STUK-B 164 Article 14 – Assessment and verification of safety application, and must be justified on the basis of and Accident Analyses for Justification of Technical the ageing and planned future operation of the nu- Solutions at Nuclear Power Plants”. Requirements clear facility. Particular attention is paid to licen- for probabilistic risk assessments are given in see’s processes and activities and planned safety the Guide YVL 2.8, “Probabilistic safety analysis improvements to ensure safety for the estimated in safety management of nuclear power plants”. duration of operation. The procedure for operating Acceptance criteria for the analyses are present- licence renewal is in general the same as in ap- ed in Guides YVL 6.2 “Design bases and gen- plying for an operating licence for a new nuclear eral design criteria for nuclear fuel” and YVL 7.1, facility. Specific requirements on the documents to “Limitation of public exposure in the environment be submitted to STUK for the renewal of the oper- of and limitation of radioactive releases from a nu- ating licence are described in the Guide YVL 1.1 clear power plant”. “Regulatory control of safety at nuclear facilities”. Renewal of the operating licence always involves Deterministic safety assessment a periodic safety review of the facility. If a licence Detailed requirements concerning transient and is granted for a significantly longer term than ten accident analyses, including sensitivity analyses, years, STUK requires the licensee to carry out a are presented in the Guide YVL 2.2, “Transient periodic safety review within about ten years of and Accident Analyses for Justification of Technical receiving the operating licence or of conducting the Solutions at Nuclear Power Plants”. previous periodic safety review. For a separate pe- Fortum submitted with the licence renewal riodic safety review, STUK must be provided with documentation in 2005–2007 the revised Final similar safety-related reports as in applying for Safety Analysis Report, including the transient renewal of the operating licence. Renewal of the op- and accident analyses of the Loviisa units 1 and erating licence of the Loviisa nuclear power plant 2. Fortum has revised the analyses taking into took place in 2005–2007 and the periodic safety account plant modifications implemented at both review of the Olkiluoto units 1 and 2 in 2007–2009 units as well as new regulatory requirements. The (see Article 6). analyses presented in the Safety Analysis Report The Government Decree on the Safety of cover anticipated operational transients, category Nuclear Power plants (733/2008) requires that nu- 1 and 2 accidents, and severe accidents. The analy- clear power plant safety and the technical solutions ses cover all operating states and include accident of its safety systems shall be substantiated by us- analyses for the storages of spent fuel and reactor ing experimental and calculation methods. These waste. Fortum has supplemented the deterministic include among others analyses of operational oc- safety analyses in 2008 by analyses of design ex- currences and accidents, strength analyses, failure tension conditions. mode and effect analyses, and probabilistic risk STUK assessed the submitted analyses for the assessments. Analyses shall be maintained and Loviisa NPP and methods applied in the analyses. revised if necessary, taking into account operating STUK contracted VTT Technical Research Centre experience, the results of experimental research, of Finland to carry out independent analyses to plant modifications and the advancement of calcu- verify the results given in the licence renewal lation methods. The calculation methods employed documentation and to conduct sensitivity analyses. for demonstrating compliance with safety regula- STUK concluded that the plant behaviour in dif- tions shall be reliable and well qualified for the ferent transient and accident situations has been purpose. They shall be applied so that the resulting analysed comprehensively and that the methods system design bases meet the acceptance criteria used in the analyses are properly validated to de- with high certainty. Any uncertainty in the results scribe the operation of the Loviisa plant. shall be assessed and considered when defining Accident and transient analyses of the Olkiluoto safety margins. STUK’s review of these analyses units 1 and 2, as well as the analysis methods, have includes independent safety analyses. been updated and developed throughout the opera- Detailed requirements concerning transient tion of the plant. TVO revised completely the acci- and accident analyses, including sensitivity analy- dent and transient analyses in conjunction with the ses, are presented in the Guide YVL 2.2, “Transient application for the renewal of its operating licence

42 Article 14 – Assessment and verification of safety STUK-B 164 in 1995–1998. The analyses were at that time car- STUK for the review of the construction licence ap- ried out for nuclear fuel that is no longer being used plication according to the Nuclear Energy Decree, at the NPP units. For the periodic safety review in but a limited preliminary PRA has been required 2007–2009, TVO updated the accident analyses us- in Regulatory YVL Guides since 1996. PRA for ing the SVEA-96 Optima 2 as a reference fuel. The construction licence application is based on pre- plant modifications carried out after the renewal of liminary design information and generic reliability the operating licence in 1998 were also taken into data for components. PRA for operating licence ap- account in the update. Since renewal of the operat- plication is based on essentially final design infor- ing licence, Guides YVL 2.2 and YVL 6.2 have been mation and vendor specific component reliability revised and a requirement regarding analyses of data, where available, and system modelling is also design extension conditions was introduced. When more detailed. updating its analyses for periodic safety review, According to the Government Decree on Nuclear TVO has taken into account the new regulation. Safety, PRA shall be maintained and revised if The calculation methods used for analysing necessary, taking into account operating experi- the plant normal operating conditions, transients ence, the results of experimental research, plant and postulated accidents were developed by the modifications and the advancement of calculation supplier of the Olkiluoto plant units. The methods methods. The detailed requirements on the use of have been qualified to an extent corresponding to PRA are set forth in the Regulatory Guide YVL 2.8. a good level from the international perspective. Detailed requirements on risk-informed applica- STUK reviewed the updated analyses and the tions are included in several other YVL Guides. calculation methods used. The conclusion was that STUK required in 1984 that the Finnish utili- the analyses of transients and accidents of the ties Fortum (former Imatran Voima Oy) and TVO Olkiluoto units 1 and 2 were conducted as referred shall make extensive probabilistic risk assess- to in Section 3 of Government Decree 733/2008. ments for the Loviisa and Olkiluoto nuclear power However, STUK required updating of the loss of plants. The objective of the study was to determine coolant analyses assuming a level of system avail- the plant-specific risk topographies of the essential ability specified in the Guide YVL 2.2. TVO submit- accident sequences. Another important objective ted the required updates in 2010. was to enhance the plant personnel’s understand- The preliminary analyses of Olkiluoto unit 3 ing of the plant and its behaviour in different were presented to STUK in PSAR and the Topical situations. Therefore STUK also required that the Reports appended to PSAR with the application for PRAs are performed mainly by the utility person- the construction licence. STUK contracted techni- nel and external consultants are used only for cal support organisations to carry out independent special topics. analyses to verify the results. STUK approved the In 1987 STUK published the Regulatory Guide PSAR of Olkiluoto unit 3 in January 2005 just YVL 2.8 on PRA. The Guide was updated in before the construction licence was granted by the 1996 and 2003. Currently the Guide requires a Government. TVO has submitted updated analyses full-scope (including internal events, fires, floods, for the Final Safety Analysis Report in 2008–2012. seismic events, harsh weather and other external The analyses will be reviewed as a part of the events) PRA for power operation and low-power Olkiluoto unit 3 operating licence application. and shut-down states. PRA shall cover the analy- sis of the probability of core damage (Level 1) and Probabilistic risk assessment large release of radioactive substances (Level 2). PRA shall be updated continuously to reflect plant Regulatory requirements on PRA and procedure modifications and changes in reli- In the Nuclear Energy Decree, probabilistic risk ability data (Living PRA). assessment (PRA) has been included since 1988 Guide YVL 2.8 includes the following probabil- in the list of documents to be submitted to STUK istic safety goals: for the review of the operating licence application. • Core damage frequency less than 1∙10-5/year Since 2008 the preliminary design phase PRA has • Large radioactive release (> 100 TBq Cs-137) been in the list of documents to be submitted to frequency less than 5∙10-7/year.

43 STUK-B 164 Article 14 – Assessment and verification of safety

These safety goals apply as such to new plant development in accordance with the Guide YVL units. For operating units, instead of the numeri- 2.8. PRA is also used in the planning of commis- cal safety goals, the SAHARA (safety as high as sioning testing programmes. reasonably achievable) principle and the principle • Risk informed methods have been used to sup- of continuous improvement are applied. port ageing management, for example, trend Guide YVL 2.8 also includes requirements on analysis of failure data. In connection with the several risk informed applications, such as analy- life extension of Loviisa unit 1 reactor pressure sis of plant modifications, risk-informed in-service vessel, the probabilistic analysis of pressurised inspections and testing, development of emergency thermal shock was used to evaluate the safety operating procedures and training programmes significance of radiation induced embrittlement and review of safety classification and Operational of weld seams. Limits and Conditions. • Risk informed approach has been used also for For a new plant unit, a preliminary PRA cover- inspections of Loviisa reactor vessel internals. ing Levels 1 and 2 shall be submitted to STUK for Preliminary results show that risk reduction the review of the construction licence application could be gained by doubling the inspection (design phase PRA) and the updated and comple- interval, which would decrease the risk due to mented PRA (Levels 1 and 2) shall be submitted heavy load drop significantly. for the review of the operating licence application. PRA’s computer models shall be made available The use of PRA in several well-established appli- to STUK. STUK uses PRA routinely to support its cations has been continued and the methods have decision making, for example, in review of plant been further refined. modifications and applications for exemption from In addition to the risk informed applications Operational Limits and Conditions and in analysis based on regulatory requirements, the licensees of operating events. use PRA in applications supporting their operat- The Guide YVL 2.8 is being updated in STUK’s ing activities, for example availability analysis and ongoing renewal of Regulatory Guides. In the new risk centred maintenance. guide YVL A.7, requirements on the use of PRA in Further development of the PRA computer code the decommissioning phase have been added and system developed at STUK has been continued in the list of applications and documents to be sub- a joint project with VTT Technical Research Centre mitted to STUK have been specified. of Finland. The software is used in the review of the PRAs submitted by the licensees and in sup- Main developments in risk informed port of risk informed decision making at STUK. regulation and safety management during the reporting period Probabilistic risk assessment During the reporting period the role of risk in- of the Loviisa NPP formed regulation and safety management has Fortum provided STUK with Level 1 PRA in 1989. been further strengthened by STUK and the licen- Since 1990 Fortum has extended PRA by analys- sees. The following activities can be given as exam- ing risks related to fires, floods, earthquakes, se- ples of the increased role of risk informed methods: vere weather conditions and outages, as well as by • Risk-Informed In-Service Inspection pro- conducting Level 2 PRA. Plant modifications have grammes for the operating units were imple- been carried out continuously at the Loviisa NPP, mented by TVO in 2012. including safety system improvements, fire safety • TVO and Fortum have applied PRA in support improvements, implementation of Severe Accident of the review of safety classification of the oper- Management systems and a major modernisation ating units. programme in mid 1990’s (see Annex 2). By means • The finalisation of the PRA for Olkiluoto unit of these modifications risks have been decreased 3 under construction is still ongoing. Risk in- and the risk topography of the plant has been formed applications have been used in the balanced. Technical solutions of the modifications design of the unit and the risk informed ap- have also been often justified with PRA. plications for the operating phase are under The development of the core damage frequency

44 Article 14 – Assessment and verification of safety STUK-B 164

Loviisa core damage frequency 2.5E-04 Figure 10. Development of the estimate of annual core 2.0E-04 damage frequency of the Loviisa NPP in 2000–2012.

1.5E-04 The increase in the core damage frequency in 2003 was due to extension of the PRA scope with non-seis- 1.0E-04 mic external events during shutdown states. The pre- liminary conservative analyses showed relatively high 5.0E-05 risk due to exceptionally high outside air temperature 0.0E-00 and oil spills in the in cold shutdown 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Internal PO Internal SD Flood PO Flood SD Seismic states. Later the risk estimate was decreased due to Fire PO Fire SD Weather PO Weather SD plant modifications and more realistic analyses.

since 2000 is shown in Figure 10. At the end of year detailed study for internal events, fires, floods and 2012 the calculated estimate for the total probabil- severe weather conditions at power states and at ity of reactor core damage was about 3.0∙10–5 per outages, whereas some specific events (seismic, reactor year. The relative contribution to the an- shutdown fires, heavy load drop, loss of DC power, nual core damage frequency from different groups etc.) are based on rough estimates on the accident of initiating events are shown in Figure 11. The progession. In 2012, mainly the following modi- Loviisa plant has full scope PRA covering Levels fications have decreased core damage frequency 1 and 2. The latest completion included fire risk and large release frequency: renewal of auxil- analysis for shutdown states in 2011. iary service water system (VF62), modifications in Fortum has also provided STUK with the Level power distribution for some containment systems, 2 PRA, in which the integrity of the containment renewal of Pressuriser Overpressure Protection and the release of radioactive materials from the Valve (PORV), renewal of pressuriser spray system plant to the environment are evaluated. In the lat- and new procedures for sump recirculation in shut- est update in 2012, it was estimated that the total down states. probability of a large release to the environment The results of STUK’s review show that Fortum is about 1.4∙10–5 per year. The estimate includes a has applied in its analyses commonly accepted methods in modelling transient and accident situ- Loviisa ations of the plant and in collecting and analysing relative risk profile 2012, total CDF 3,05E-5 reliability data. The reviews also show that the assessments provide an adequate basis for risk 14% 10% Internal PO informed decision making. Internal SD 10% Flood PO PRA has been used by the licensee in the risk- 3% 36% Fire PO informed applications required by the Guide YVL Fire SD 2.8, for example in evaluation of plant modifica- 25% Weather PO tions, review of safety classification, development Weather SD of Risk-Informed In-Service Inspection programme. 2% The risk informed review of the Operational Limits Figure 11. Relative contribution of different initiating and Conditions, including optimisation of testing event types to the annual core damage frequency intervals, and optimisation of Operational Limits in 2012 for Loviisa NPP. The most significant internal and Conditions (allowable outage times) is under initiating events at full power (power operation, PO) way. The Loviisa NPP has also introduced a Risk- are the small interfacing system LOCAs and the loss of instrumentation room ventilation. At shutdown (SD) Informed In-Service Inspection programme for pip- the most significant internal initiating events are drop ing. The number of inspections was increased but of heavy loads and reactivity accident due to boron the focus shifted from high safety classes to lower dilution. Note: “Flood” includes only internal flooding safety classes. This shift is due to the fact that from process systems and external flooding is includ- some lower safety class pipings have relatively ed in “Weather”. large risk significance as they belong to vital sup-

45 STUK-B 164 Article 14 – Assessment and verification of safety

Okiluoto 1 and 2 core damage frequency 2.5E-05

2.0E-05

1.5E-05 2000–2012. The decrease in seismic risk in 2009 is due to plant modifications allowing improved handling of 1.0E-05 spurious activation of isolations due to relay chatter.

5.0E-06 The risk estimate increase in 2009 is due to a more detailed analysis of the capacity of decay heat removal 0.0E-00 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 by diverse systems. The risk estimate increase in 2011 Internal Flood Fire Shutdown Weather Seismic is due to the change of the method used to deter- mine fire ignition frequencies and update of external Figure 12. Development of the estimate of annual hazards study that contains a new man-made hazard core damage frequency for Olkiluoto units 1 and 2 in “marine oil-spill”.

port systems, or leaks in lower class pipelines may severity of the release has decreased significantly lead to consequential damage to safety systems. mainly due to modifications in procedures. The radiation doses to inspection personnel will TVO has used PRA in the risk-informed appli- decrease as a result of the new inspection pro- cations required by the Guide YVL 2.8, for exam- gramme. ple in evaluation of plant modifications, review of safety classification, development of Risk-Informed Probabilistic risk assessment of In-Service Inspection programme, optimisation of the Olkiluoto units 1 and 2 testing intervals, and optimisation of Operational TVO submitted to STUK the first version of Level Limits and Conditions (allowable outage times). 1 PRA in 1989. Since then, the PRA has been updated several times and the scope has been ex- Probabilistic risk assessment tended. TVO has now practically full-scope PRA of Olkiluoto unit 3 covering levels 1 and 2 for full power operation and The vendor of Olkiluoto unit 3 conducted a design for low power and shutdown states. phase PRA, which TVO submitted in 2004 to STUK Annual core damage frequency since 2000 is for the review of the construction licence applica- shown in Figure 12. Plant modifications have been tion as required by the Nuclear Energy Decree. The carried out continuously at the Olkiluoto plant, design phase PRA includes analysis of internal including backfitting with severe accident manage- initiating events, internal hazards and external ment systems and power uprate and modernisa- hazards for power operation and refuelling out- tion in the 1990’s (see Annex 2).

At the end of 2012 the overall core damage fre- Olkiluoto 1 and 2 relative risk profile 2012, total CDF = 1,34E-5 quency of Olkiluoto units 1 and 2 is approximately 1% 1.3∙10–5 per reactor year, including all operating states and all groups of initiating events. The Seismic 21% relative contributions to annual core damage fre- Weather Shutdown quency from different groups of initiating events 4% 54% Fire are shown in Figure 13. Flood 19% In 1996, TVO submitted to STUK the Level 2 Internal PRA. The analysis has been updated a few times since then. According to the living PRA model 1% in 2010 the frequency of the large release to the Figure 13. Relative contribution of different initiating environment (>100 TBq Cs-137) was 3.5∙10–6 per event types to the annual core damage frequency in reactor year, which was approximately one tenth of 2012 for Olkiluoto units 1 and 2. The most significant internal initiating events at full power are the loss of the core damage frequency. The large release fre- off-site power and loss of feedwater. Note: “Flood” quency has decreased in the updates mainly due to includes only internal flooding from process systems the decrease of the core damage frequency, but the and external flooding is included in “Weather”.

46 Article 14 – Assessment and verification of safety STUK-B 164 age. STUK approved the Olkiluoto 3 PRA for the Employment and the Economy on 16 May 2011. construction licence in January 2005. The PRA of Although immediate actions to ensure safety of Olkiluoto 3 has been continuously updated by the public and environment were not considered neces- plant vendor during the construction phase and sary, STUK required the licensees to carry out ad- STUK has closely followed the completion of the ditional assessments and present action plans for PRA. safety improvements. Assessments were conducted Olkiluoto unit 3 preliminary PRA covers seismic and reported by the Finnish licensees to STUK on events and other external events (harsh weather, 15 December 2011. STUK has reviewed the results organic material in seawater etc.). According to the of national assessments, and made licensee specific preliminary results, Olkiluoto unit 3 fulfils with a decisions on 19 July 2012 on the suggested safety wide margin the probabilistic safety goals set forth improvements and additional analyses. in the Guide YVL 2.8. The contribution of seismic Finland also participated in the EU Stress Tests events is less than 1 per cent of the total CDF and and submitted the national report to European the contribution of other off-site external events Commission at the end of 2011. An EU level peer is less than 10 per cent of the total CDF. The most review on the report was completed by April 2012. important external events are strong wind with The recommendations of the EU peer review have snowfall and the loss of the ultimate heat sink due been taken into account in the regulatory deci- to oil spill, organic material in seawater or frazil sions and will be considered in the development of ice. national regulations. A National Action Plan was Preliminary results of level 2 PRA show that prepared addressing the measures initiated on large release frequency of Olkiluoto unit 3 is very a national level and at the nuclear power plants small. In addition, the distance of the magnitude as a result of the TEPCO Fukushima Daiichi ac- and frequency of releases from the unacceptable cident. The National Action Plan was sent to the region are clearly large, and only 2 per cent of the European Nuclear Regulators Group (ENSREG) releases are in the vicinity of the limit for large and peer reviewed in April 2013. In addition, release. Thus, future refinement of the analyses is Finland participated in the second Extraordinary not expected to change the magnitudes of releases. Meeting of the Convention of Nuclear Safety (CNS) PRA has been used by TVO and plant vendor in August 2012 and prepared a report introduc- in the risk-informed applications required by the ing all Fukushima related actions. All STUK’s Guide YVL 2.8, for example in evaluation of sys- related decisions, the national report to European tem design, review of safety classification, devel- Commission, the report to the Extraordinary CNS, opment of Risk-Informed In-Service Inspection and the Finnish National Action Plan have been programme, optimisation of testing intervals, op- published on STUK’s website. timisation of Operational Limits and Conditions Based on the results of assessments conducted (allowable outage times), and planning of plant in Finland to date, it is concluded that no such commissioning tests. hazards or deficiencies have been found that would require immediate actions at the Finnish NPPs. Assessment of safety as a result of However, areas where safety can be further en- TEPCO Fukushima Dai-ichi accident hanced have been identified and there are plans on Following the accident at the Fukushima Dai-ichi how to address these areas. The experiences from nuclear power plant on the 11th of March in 2011, the TEPCO Fukushima Dai-ichi accident are also safety assessments in Finland were initiated af- taken into consideration in the ongoing renewal ter STUK received a letter from the Ministry of of the legislation and Finnish Regulatory Guides Employment and the Economy on 15 March 2011. (YVL Guides) and in the nuclear safety research The Ministry asked STUK to carry out a study programme SAFIR 2014 (see Articles 7 and 8). on how the Finnish NPPs have prepared against Safety improvements under planning and imple- loss of electric power supply and extreme natu- mentation at the Finnish NPPs due to the TEPCO ral phenomena in order to ensure nuclear safety. Fukushima Dai-ichi accident are described more STUK asked the licensees to carry out assessments detailed under Articles 16, 17, 18 and 19, and in and submitted the study report to the Ministry of Annexes 2, 3 and 4.

47 STUK-B 164 Article 14 – Assessment and verification of safety

Information collected in connection with exter- inspections by contractors approved separately. nal events PRAs has been used in the national and Detailed programmes and procedures are estab- EU stress tests after the TEPCO Fukushima Dai- lished and approved by the licensee. They are also ichi NPP accident, although mainly deterministic reviewed and, when needed, approved by STUK. approach has been used. Seismic events and other The results of tests and inspections are document- off-site external events have been included in the ed in a systematic way and used through a feed- PRAs in the 1990’s and the analyses have been up- back process to further develop the programmes. dated regularly. The input data and plant response The Operational Limits and Conditions are ap- analyses used in the external events PRAs have proved by STUK. In general, the role of STUK is been reviewed after the TEPCO Fukushima Dai- to verify that the licensees follow the obligations ichi NPP accident in connection with the stress imposed on them and carry out all activities sched- tests and no essential shortcomings have been uled in verification programmes. found. Further updates of the analyses and hazard Comprehensive evaluations related to the state estimates will be continued. and operation of the Loviisa and Olkiluoto plants were carried out in the periodic safety reviews Verification of safety by Fortum in 2005–2007 and TVO in 2007–2009. These activities were controlled by STUK. Verification programmes Government Decree 733/2008 includes several re- Inspection qualification quirements which concern the verification of the According to international experience and the physical state of a nuclear power plant. For in- Guide YVL 3.8, STUK has recognised the qualifica- stance, in all activities affecting the plant opera- tion of non-destructive testing systems and proce- tion and the availability of components, a system- dures as an issue of high importance. This issue re- atic approach shall be applied for ensuring the quires high priority at both nuclear power plants. operators’ continuous awareness of the state of the The implementation of qualified NDT systems has plant and its components. The reliable operation of been started in 1990’s. systems and components shall be ensured by ade- General requirements on inspection qualifica- quate maintenance as well as by regular in-service tion are provided in the Guide YVL 3.8. The inspections and periodical tests. General require- document “European methodology for qualifica- ments on verification programmes and procedures tion” drawn up by the European Network for are provided in the YVL Guides (e.g. Guide YVL Inspection and Qualification (ENIQ) shall be used 1.8, YVL 1.9, YVL 3.0, YVL 3.8). as the minimum requirement level for qualifica- Main programmes used for verification of the tion of inspection systems to be used in in-service state of a nuclear power plant are inspection, and it shall be complemented by the • periodic testing according to the Operational ENIQ Recommended Practices. In the content of Limits and Conditions licensees’ guidelines published by the qualification • maintenance programme body, the requirements presented in the Guide YVL • in-service inspection programme 3.8, in the European Methodology for Qualification • periodic inspections of pressure equipment and (EUR 17299) and in its recommendations have piping been taken into account. • surveillance programme of reactor pressure The licensees Fortum and TVO have estab- vessel material lished the Steering Committee for Qualification • programmes for evaluating the ageing of com- and nominate its members on annual basis. The ponents and materials. Steering Committee for Qualification is guiding and supervising the practical qualification work Activities for verifying the physical state of a pow- with the help of a separate Technical Support er plant are carried out in connection with nor- Group nominated and supervised by the Steering mal daily routines and with scheduled inspections, Committee. testing, preventive maintenance etc. Activities are Based on a contract with the licensees, Inspecta performed by the licensee and in the case of certain Certification is nominated as the qualification

48 Article 14 – Assessment and verification of safety STUK-B 164 body for qualification management, implementa- bases for the in-service inspection programmes tion, control and assessment as well as the issuing and procedures. ASME Code, Section XI, Appendix of qualification certificates in Finland. The Finnish R and ENIQ European Framework Document for qualification body is a qualification body of type 1, Risk-informed In-service Inspection are used as which is an independent third party organisation approval bases for the risk-informed in-service in- as defined by ENIQ Recommended Practice 7. spection programmes. When needed Inspecta Certification uses also ex- The reliability of the non-destructive exami- perts outside of its own organisation for individual nation methods for the primary circuit piping qualifications. and components has been essentially improved Most of the qualifications have already been after the commissioning of the both Loviisa and performed and approved by STUK. Olkiluoto NPPs. Guide YVL 3.8 calls for the qual- STUK ordered in 2009 an assessment of the ification of the entire NDT-system; equipment, current qualification activities in Finland from an software, procedures and personnel. Most of the independent expert organisation. The purpose was inspection systems are already qualified at the to assess whether Finnish inspection qualification both plants. STUK follows the development and practice leads to reliable and effective in-service in- implementation of the plans. spection of safety critical components. Review was A risk-informed inspection programme has been performed in two parts: 1) review of the inspec- introduced and approved by STUK at the Loviisa tion qualification system as specified in the Guide units 1 and 2 for the inservice inspections of safety- YVL 3.8 and the national qualification guideline critical pipelines. The deployment of risk-informed documents issued by the qualification body and inspection methods for targeting inspections has 2) review of the inspection qualification practices. been developed in Finland by STUK, Fortum, As a conclusion of the assessment it was reported Fortum, TVO and VTT. The objective of risk-in- that the qualification system meets the Finnish re- formed in-service inspection programmes is to al- quirements, is effective and provides confidence in locate inspection resources to the targets that are the inspections of safety critical components. most critical from the point of view of risk. Using this approach, it is possible to ensure that the cur- In-service inspections rent inspection objects are well-justified, identify The condition of the pressure-retaining compo- new objects and omit certain less safety-critical nents of the Loviisa and Olkiluoto NPPs is en- objects from the existing inspection programme. sured with regular in-service inspections. The com- According to experts’ view, the programme is the ponents of the primary circuit are inspected by most extensive risk-informed in-service inspection means of non-destructive examination methods. programme so far implemented in Europe. These regularly repeated examinations are carried The length of the inspection period of the out during outages according to the Guide YVL 3.8. regular inspections (e.g. ASME Code, Section XI) is The results of the in-service inspections are com- normally ten years. Inspection programmes have pared with the results of the previous inspections been complemented with additional inspections and of the pre-service inspections which have been as regards the reactor pressure vessel and the pri- carried out before the commissioning. mary circuit piping, and the length of the inspec- The in-service inspection plans are submit- tion period of the reactor pressure vessel has been ted to STUK for approval before each individual reduced to eight years. The length of the inspection in-service inspection. Programmes and related in- period of the objects susceptible to thermal fatigue spection procedures are changed when necessary, is typically three years. taking into account the development of require- At the Olkiluoto plant, attempts have been ments and standards in the field, the advancement made to focus the inspections on areas where faults of examination techniques and inspection experi- are most likely to emerge. These include, for exam- ences as well as operating experiences in Finland ple, items susceptible to fatigue due to tempera- and abroad. ture variations or items susceptible to stress corro- Guide YVL 3.8 and the latest revisions of the sion cracking. The selection of inspection items is ASME Code, Section XI are applied as approval under continuous development. For this purpose, a

49 STUK-B 164 Article 14 – Assessment and verification of safety

risk-informed in-service inspection procedure has tackle both the technical aspects of each discipline been developed for the Olkiluoto units 1 and 2 and and the process of ageing management. STUK also it has been approved by STUK. Inspections and receives annual reports from each nuclear power inspection schedules will be optimised on the basis plant unit on ageing management activities within of risk-informed methods when the next inspection each technical discipline. interval programmes are drawn up. An expert group dedicated to ageing manage- The frequency of the non-destructive examina- ment has been established within STUK to over- tions performed at regular intervals is usually ten see how the licensees perform their duties in the years at the Olkiluoto NPP. The inspection fre- ageing management of SSCs. The group, which quency for items susceptible to thermal fatigue is consists of mechanical, electrical, I&C, civil and three years, and the inspection frequency for items human resource experts and resident inspectors, susceptible to stress corrosion cracking is three to looks into such events and observations at the five years. Finnish nuclear plants that may be related to In addition to the inspections mentioned above, inadequate ageing management. If shortcomings physical inspections concerning the condition and are found, for example in condition monitoring or reliability of pressure equipment are carried out maintenance, the group calls the licensee for fur- as regular pressure equipment inspections accord- ther clarications or corrective actions. The group ing to the Finnish pressure equipment legislation. also follows up findings from other countries and Such inspections are a full inspection, an internal evaluates their possible linkage to the ageing inspection and an operational inspection. These management of the Finnish nuclear plants. In the inspections include non-destructive examinations overall renewal of the STUK’s regulatory guides, a as well as pressure and tightness tests. The inspec- dedicated regulatory guide is developed for ageing tions of piping have been defined in the system- management, i.e. YVL A.8. specific monitoring programmes. These periodic inspections are dealt with in the Guides YVL 3.0, Ageing management at the Loviisa NPP YVL 3.3, YVL 5.3, and YVL 5.7. The periodic in- Radiation embrittlement of the reactor pressure spection programmes of the Loviisa and Olkiluoto vessel (RPV) and the related surveillance and miti- NPPs fulfil the requirements of YVL Guides, as gation actions dominated the ageing management regards the number and techniques of inspections. in Loviisa NPP since the early years of operation. This was more relevant to Loviisa unit 1 whose Ageing management girth weld at the level of the reactor core has a According to the Government Decree (733/2008), higher content of impurities. In 1996, the brittle the design and construction of a nuclear power weld joint of the Loviisa 1 reactor pressure vessel plant shall include provision for the ageing of sys- was heat-treated to improve the ductility proper- tems, structures and components (SSCs) important ties of the welding material. In this connection the to safety. Their condition shall be monitored to reactor pressure vessel was subject to thorough ensure operability and conformity in design-basis non-destructive tests. Embrittlement rate has conditions. The needed replacements, repairs and been re-assessed based on the new surveillance modifications, shall be carried out in a systematic programme representing the critical weld. STUK manner. has granted the operating licences of the RPVs for The regulatory oversight of ageing in operating the Loviisa units 1 and 2 until 2027 and 2030, re- plants focuses on operating licence renewals and spectively. For both units, deterministic and proba- Periodic Safety Reviews (PSRs) where the conform- bilistic safety analyses will be updated in the PSRs ance to the relevant Government Decrees and YVL (by end of 2015 and 2023) in order to justify contin- Guides, including experiences with ageing and ued servive of the RPVs. In addition, new findings its management, is investigated. STUK’s findings from domestic and international inspection and from other regulatory control practices, particu- research programmes may require updating of the larly the periodic inspection programme, are used RPV analysis results. as verification. The periodic inspections are done In the mid-1990’s, Fortum implemented their on plant site according to annual planning and systematic plant-wide ageing management pro-

50 Article 14 – Assessment and verification of safety STUK-B 164 gramme. The SSCs are assigned to categories A mitigated IGSCC and led the way to the utility’s through D based on their technical and economical strategy of seeing to the critical SSCs so that a replaceability. SSC failures in category A would remaining plant life-time of 40 years (design life- limit plant lifetime and thus deserve a part-assem- time) could be always demonstrated. bly-wise break-down of ageing related remedies. Since 1991, the AGE Group, with assistance of Category A comprises the main primary compo- several technical discipline related expert groups, nents. Data indicative of plant status and trends has taken care of these activities by gathering are collected with operation, maintenance and in- information of possibly needed future actions from spection IT systems, R&D activities and via experi- several sources and by preparing and updating a ence exchange. The consequent ratings of operabil- table of recommended major modifications, replace- ity, remaining service life and necessary actions for ments, repairs and overhauls. The modernisation each SSC are stored on the plant database. and power uprating of the Olkiluoto units 1 and In 2006 the operating utility Fortum submitted 2 by 16% in 1994–1996 evolved from these recom- to the Government an application to continue the mendations and was completely carried out by the operation of Loviisa units 1 and 2 until the end of utility’s technical support organisation residing on 2027 and 2030, respectively, meaning a 20-year ex- plant site. The associated significant renewal cam- tension to the original design lifetime. Among the paigns of obsolete electrical and instrumentation ageing-related justification were the main fatigue systems and components largely contributed to analyses, updated to cover the whole 50 years’ current 20-year operating licence periods terminat- life span with consideration of the environmen- ing in 2018. Efforts to enhance the reliability and tal effects. Documents on In-Service Inspection good performance of the plant components, and to Summary Programme, Ageing Management ensure the spare part and support service availa- Programme Principles and Implementation, and bility have continued until recent years. The major SSC Status and Service Life Extensibility were foreseeable modifications until decommissioning also submitted. For electrical and I&C components have been identified. it was noted that massive projects are underway to Systematic maintenance planning is an integral replace cables in containment due to its detected part of ageing management at the Olkiluoto units considerable ambient temperature rise, and for 1 and 2. Nominated owners of equipment groups, plant-wide replacing of obsolete protection and characterised by a common type or location, ana- plant I&C systems and components. In its review, lyse the entire maintenance programme and its STUK made a general point that the state-of-the- experiences, and assist in selection of the most ef- art permitted a quantitative life-time evaluation fective maintenance works. Annual findings from only in case of ageing by fatigue. However, other each equipment group are stored into a relational potential mechanisms have been identified and data base on the plant computer. resources are in place to monitor, inspect, mitigate STUK reviewed TVO’s clarification on the ac- and repair as needed. The operating organisation tual condition and ageing implications of the main has also strong technical support which has con- SSCs in connection to the Periodic Safety Review vincingly resolved forthcoming ageing issues in the (PSR) carried out in 2007–2009. Supporting as- past, and the history records are well preserved. sessment has been done in several periodical in- The Government granted the applied operating li- spections on plant site. The main components were cences on condition that two PSRs are undertaken generally found to be in good condition, but the during the licence period. appearance of IGSCC in Nickel-based alloys could not be excluded and it possibly explains an indica- Ageing management at the Olkiluoto NPP tion reported from the safe-end weld of the main The ageing management activities at the Olkiluoto feedwater nozzle, made from Alloy 182. The indica- units 1 and 2 arose from wide-spread indications of tion has, however, remained unchanged as evalu- inter-granular stress corrosion cracking (IGSCC) ated by NDT-inspections during annual outages. in reactor auxiliary system piping. Early replace- The PSR also referred to a completed pilot project ment of entire piping systems, achievable with for updating fatigue analyses of selected systems modest doses to maintenance staff, considerably to incorporate the environmental effect as re-

51 STUK-B 164 quired in the implementation process of the Guide Regulatory requirements regarding YVL 3.5. Based on recommendations from expert radiation protection consultancy of VTT Technical Research Centre of The main regulations governing radiation pro- Finland, more refined modelling is employed now tection of Nuclear Power Plant operation are that the utility is renewing all fatigue analyses to the Radiation Act (592/1991), Radiation Decree justify a prospective re-licensing of the Olkiluoto (1512/1991), Government Decree for Nuclear units 1 and 2 for an operating life of 60 years. Safety of NPPs (733/2008) and YVL Guides, Part At the Olkiluoto unit 3, the ageing management 7 (12 guides). Radiation Decree stipulates that the is taken into account at the design phase. The most effective dose caused to a worker shall not exceed severe operating conditions and long-term influ- an average of 20 millisieverts (mSv) per year in ences, under which an individual component is any five years period, nor 50 mSv in any single expected to serve as a part of a process system, are year. The limit for the annual dose of an individual used to determine the design basis requirements in the population, arising from the normal opera- for that component. With known design basis re- tion of a nuclear power plant, is 0.1 mSv. Based quirements and defined life times of SSCs, their on this, STUK shall upon application confirm the materials, fabrication and other ageing manage- release limits for radioactive materials during the ment related issues are specified accordingly. This normal operation of a nuclear power plant. ALARA includes precautions against foreseeable degrada- requirement is issued in the Radiation Act and tion mechanisms with state-of-the art technology, more in detail implementation requirements are and provision for inspections, overhauls, testing given in the YVL Guides both for NPP workers and and replacements as needed while respecting the release abatement. During 2010–2012 no changes ALARA principle. The anticipated life-span of the in the Guides as regards radiation protection were main technologies and independence from single made. New regulatory guides are drafted as part of technologies are particularly considered in I&C the overall revision of the regulatory guides. system and somponent design. The design and fab- rication of SSCs are verified with qualified analy- Radiation doses of NPP workers ses, inspections and testing, overseen by STUK, in An ALARA programme, updated in 2009, exists for order to demonstrate fulfillment of quality and per- workers at the Loviisa NPP. It includes as main ob- formance requirements set by the design specifica- jectives the continuous improvement in the collec- tions. During Olkiluoto unit 3 operation, the ageing tive dose indicator trend: decreasing of a four years of SSCs and retaining the design margins will be average, now being at 0.6 manSv/reactor unit/year. managed by dedicated programmes and monitor- Important measures are e.g. minimisation of an- ing tools, and by in-service inspections to whose timony 122 and 124 content on primary circuit planning risk-informed methods are applied. surfaces and optimised use of additional shielding In conclusion, Finnish regulations and practices in the primary coolant circuit area during outages. are in compliance with Article 14. One of the reactor coolant pump seals was replaced with an antimony-free material during outage in Article 15. Radiation protection 2012. It has been estimated that the original seals Each contracting Party shall take the appro- of the coolant pumps are the main reason for ac- priate steps to ensure that in all operational tivation products of antimony 122 and 124 in the states the radiation exposure to the workers primary circuit. The rest of the seals will be re- and the public caused by a nuclear installa- placed with antimony-free seals during the next tion shall be kept as low as reasonably achiev- years if results from the new seal are acceptable. able and that no individual shall be exposed ALARA programme includes also the goal that no to radiation doses which exceed prescribed employee at the plant should receive a radiation national dose limits. dose exceeding 15 mSv per year. As a plant modifi- cation, rearrangement of controlled area activities for decontamination and operational waste man- agement was made in 2010.

52 Article 15 – Radiation protection STUK-B 164

Table 1. Annual radiation doses of workers at the Table 2. Annual radiation doses of workers at the Olki- Loviisa NPP in 2010–2012. luoto NPP in 2010–2012. Collective Maximum Average Collective Maximum Average dose personal dose dose*) dose personal dose dose*) Year [manSv] [mSv] [mSv] Year [manSv] [mSv] [mSv] 2010 1.57 15.8 2.27 2010 0.90 9.1 0.72 2011 0.71 7.9 1.39 2011 0.96 9.3 0.76 2012 1.68 14.3 2.35 2012 0.72 9.0 0.90

*) Calculated by using the registered radiation doses, which are ≥ 0.1 mSv/ *) Calculated by using the registered radiation doses, which are ≥ 0.1 mSv/ month. month.

TVO’s ALARA programme for the Olkiluoto receive a radiation dose exceeding 10 mSv per year. NPP contains a compilation of major objectives In the programme, there are also target limit val- and procedures regarding the radiation protection, ues for main radioactive effluents like noble gases, reduction of the doses of employees and target iodine isotopes, water-borne releases and tritium, values for main radioactive effluents. The ALARA too. The goal is that annual effluents are less than programme was updated in 2010 and it is included the target values which are based on real amounts in TVO’s radiation protection manual, which is reg- of annual releases from the Olkiluoto NPP. In ad- ularly updated. The ALARA programme includes dition, TVO has a specific ALARA group where the goals that collective dose should not exceed the topics of the ALARA programme has been dis- 1 manSv for two reactor units in a normal year cussed regularly 3–4 times per year. (1.5 manSv when major additional maintenance is TVO has continued the replacement of cobalt- needed) and that no employee at the plant should containing components in the primary circuit with

manSv 3.5 Loviisa 3.0

2.5

2.0

1. 5

1. 0

0.5

0.0 2011 2010 2001 2012 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2002 2003 2004 2005 2006 2007 2008 2009 2000

Figure 14. Collective annual occupational doses at the Loviisa nuclear power plant. manSv 3.5 Olkiluoto 3.0

2.5

2.0

1. 5

1. 0

0.5

0.0 2011 2010 2001 2012 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2002 2003 2004 2005 2006 2007 2008 2009 2000

Figure 15. Collective annual occupational doses at the Olkiluoto nuclear power plant.

53 STUK-B 164 Article 15 – Radiation protection

Table 3. Radioactive effluents from the Loviisa NPP. The proportion of the releases as compared to the limit values is given in parenthesis. Airborne effluents Liquid effluents Iodine I-131 ekv. Aerosols excluding tritium Year Noble gases Kr-87 ekv. [Bq] [Bq] [Bq] [Bq] 2010 5.88E+12 (0.03 %) 4.84E+07 (0.02 %) 1.18E+08 1.77E+08 (0.02 %) 2011 6.29E+12 (0.03 %) 8.58E+05 (0.0004 %) 1.10E+08 1.88E+08 (0.02 %) 2012 5.56E+12 (0.04 % *) 2.25E+05 (0.0001 %) 1.03E+08 3.06E+08 (0.03 %) *) Release limit for noble gases was changed in 2012.

Table 4. Radioactive effluents from the Olkiluoto NPP. The proportion of the releases as compared to the limit values is given in parenthesis.

Airborne effluents Liquid effluents excluding tritium Iodine I-131 ekv. Aerosols Year Noble gases Kr-87 ekv. [Bq] [Bq] [Bq] [Bq] 2010 5.81E+11 (0.003 %) 9.40E+07 (0.08 %) 1.17E+07 2.39E+08 (0.08 %) 2011 1.24E+12 (0.007 %) 1.74E+06 (0.002 %) 1.50E+07 1.38E+08 (0.05 %) 2012 1.21E+12 (0.01 % *) 1.70E+07 (0.02 % *) 1.63E+07 2.04E+08 (0.07 %)

*) Release limits for noble gases and iodine were changed in 2012. new ones with low cobalt content. Cobalt-containing has made it possible to keep their duration short, components have been reduced from the original which usually reduces the amount of work car- value of each plant unit, by more than 40 %. The ried out and hence also the exposure to radiation. reduction in moisture of primary steam with the Loviisa NPP has succeeded in decreasing the col- equipment upgrades (new steam dryers) during lective dose of the personnel and is well in com- 2005–2007 at the Olkiluoto NPP has continued the parison with different type of PWRs. substantial reduction of radiation dose rates at the turbine plant during 2010–2012. The risk-informed Radioactive effluents procedure was deployed to in-service material in- STUK confirms upon the licensee’s application spections in piping and welding for the first time the release limits for radioactive materials dur- in outages 2012 at the Olkiluoto NPP. This has also ing the normal operation of a nuclear power plant. contributed towards reducing the amount of work Operational Limits and Conditions have more carried out in most radioactive areas, thus reducing stringent requirements applicable for the radioac- the radiation exposure of the employees. tive substances of primary coolant (fuel integrity), The radiation dose statistics of the workers are thus practically preventing releases. Fuel rods at presented for the Loviisa and Olkiluoto nuclear the Olkiluoto and Loviisa nuclear power plants power plants in Tables 1 and 2 and Figures 14 have had very low failure rates. Both nuclear pow- and 15. The individual radiation doses have re- er plants have efficiently implemented measures to mained well under the set annual and five years reduce the releases of radioactive substances into dose limits. The maximum combined dose of a the environment. Finnish worker at the NPPs for a single year dur- The radioactive effluents from the plants in ing 2010–2012 was 15.8 mSv. For a 5 years period 2010–2012 are shown in Tables 3 and 4. Radio­ 2008–2012, the maximum dose was 53.8 mSv and active releases into the environment from the was received by a person working at the Loviisa Finnish nuclear power plants have been well below nuclear power plant. authorised limits (for important nuclides and path- In international comparison (e.g. the ISOE ra- ways, of the order of 0.01% to 0.1% of set values diation dose database of the NEA, the Nuclear based on the requirements). Calculated radiation Energy Association of the OECD countries), the exposures to the individual of the critical group liv- Olkiluoto units 1 and 2 have been among the best ing in the environment of the nuclear power plants boiling water reactors when comparing both in- are shown in Figure 16. dividual and collective radiation doses. The long- STUK received reports from Fortum (the lat- term planning of annual maintenance operations est report in 2011) and TVO (the latest report in

54 Article 15 – Radiation protection STUK-B 164

2010) on the implementation of the Guide YVL 7.1 Environmental radiation monitoring concerning the potential solutions (Best Available STUK has approved the operating programme for Techniques, BAT) for further reduction of the radi- environmental radiation monitoring in the sur- oactive discharges from the Loviisa and Olkiluoto roundings of the Loviisa and Olkiluoto NPPs for NPPs. Fortum has developed caesium removal 2012–2016. The changes in the programme com- technology from liquid releases which is in success- pared with the previous one were related to, inter ful operation. The utility reviewed VVER reactor R alia, the use of reference samples, changes in gar- & D issues and evaluated their own developments dening and agricultural product samples, collect- underway. They recognized some techniques worth ing frequencies of samples, measurements of the of further research and development. TVO and the water treatment plant sludge and the interpreta- Olkiluoto power plant had previously carried out tion of measurement results on carbon-14 nuclides. improvements on water treatment and purifica- Environmental Radiation Monitoring Depart­ tion of discharge waters, and no new solutions ment of STUK has acted as an outside contracted were presented now. TVO had also an independent laboratory for the licensee. The outside contracted assessment, comparing the emissions and operat- laboratory collects and analyses about 300 samples ing experience in the Olkiluoto plant units and in (air, fallout, sediment, indicator organisms, milk, equivalent Swedish BWRs. The results indicate etc.) per year from the environment of both Loviisa that the standard of radiation protection is also and Olkiluoto NPPs. Very small quantities of radio- in this respect at least of the same level as in the active substances of local origin were detected in reference plant units surveyed. STUK concluded 2010–2012 on some samples from the environment that the both utilities apply the BAT principle to of both nuclear power plants. Concentrations of the abatement of radioactive discharges of their power radioactive substances were very low, and effects plants. on the public are insignificant.

µSv 4.0 3.5 Loviisa 3.0 2.5 2.0 1. 5 1. 0 0.5 0.0 2011 2010 2001 2012 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2002 2003 2004 2005 2006 2007 2008 2009 2000

µSv 2.0

Olkiluoto 1. 5

1. 0

0.5

0.0 2011 2010 2001 2012 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2002 2003 2004 2005 2006 2007 2008 2009 2000

Figure 16. Calculated annual radiation exposures to the members of critical groups in the environment of the Finnish nuclear power plants. Doses have been clearly under the limit 100 μSv.

55 STUK-B 164

The IRRS review team identified that STUK maintenances. The inspections at the Loviisa and should withdraw from the current practice of Olkiluoto NPPs have shown e.g. that the plants conducting the environmental monitoring pro- have introduced technical and IT administration grammes in the vicinity of the nuclear facilities improvements in the field of radiation protection, based on commercial contracts with the licensees. which made it possible to enhace the control of oc- Furthermore, STUK should implement an inde- cupational radiation doses and contamination. pendent monitoring programme for the environ- In conclusion, Finnish regulations and practices ment, to verify the results of the off-site environ- are in compliance with Article 15. mental monitoring programmes required from the licensees. Based on the IRRS recommendation, Article 16. Emergency preparedness there is a plan to change the Finnish Nuclear 1. Each Contracting Party shall take the ap- Energy Act in the near future. propriate steps to ensure that there are on- site and off-site emergency plans that are Regulatory oversight routinely tested for nuclear installations On the basis of documents submitted by the licen- and cover the activities to be carried out sees, STUK approved in 2012 the use of the dosim- in the event of an emergency. For any new etry service of the Loviisa nuclear power plant and nuclear installation, such plans shall be the Olkiluoto nuclear power plant until 2016. As prepared and tested before it commences appropriate, the approval also covers the agree- operation above a low power level agreed ment between the licensee and the outsourced ser- by the regulatory body. vices provided by the company Doseco Oy, respon- 2. Each Contracting Party shall take the ap- sible for routine dosimetry at the Olkiluoto NPP. propriate steps to ensure that, insofar as STUK has audited the dose monitoring service at they are likely to be affected by a radio- Doseco Oy. logical emergency, its own population and The dosimeters used for measuring the occu- the competent authorities of the States in pational radiation doses of Loviisa and Olkiluoto the vicinity of the nuclear installation are plants have underwent STUK’s annual tests with provided with appropriate information for acceptable results. These tests comprise irradiat- emergency planning and response. ing a random sample of dosimeters at STUK’s radi- 3. Contracting Parties which do not have a ation standard laboratory and determination of the nuclear installation on their territory, in- doses at the power plant (blind test). Although the sofar as they are likely to be affected in the test results were acceptable, it was found that the event of a radiological emergency at a nu- test results of the Loviisa NPP for surface doses clear installation in the vicinity, shall take were systematically conservative. Closer investi- the appropriate steps for the preparation gation revealed that the surface doses reported to and testing of emergency plans for their the dose register in 2011 were relatively higher in territory that cover the activities to be car- relation to deep doses when compared to previous ried out in the event of such an emergency. years. As a corrective action, technical and admin- istrative changes were made to the radiation dose Emergency preparedness on-site of NPPs determination algorithms at the Loviisa NPP in Regulations concerning emergency preparedness 2012. and response arrangements at the NPPs are given STUK carries out annual radiation protection in the Nuclear Energy Act, the Nuclear Energy inspections on-site according to the periodic in- Decree and the Government Decree on Emergency spection programme, e.g. covering the resources, Response Arrangements at Nuclear Power Plants expertise and operation of the radiation protec- (735/2008). Detailed requirements and STUK’s tion organisation, dosimetry, radiation measure- oversight procedures are given in the Guide YVL ments in the plant, radioactivity measurements 7.4. of effluents, and monitoring of radiation in the The Government Decree on Emergency Res­ environment. STUK carries out on-site inspections ponse Arrangements at Nuclear Power plants is related to radiation protection also during annual under renewal and the new Decree is expected to

56 Article 16 – Emergency preparedness STUK-B 164 become effective in 2013. Parallel to that the Guide The facilities of the emergency response organi- YVL 7.4 is revised according to the Decree tak- sation at the Loviisa and Olkiluoto nuclear power ing also into account the lessons learned from the plants include a system for displaying data directly TEPCO Fukushima Dai-ichi accident. In the new from the process computer. Several hundred pa- Decree, there is a requirement to take into account rameters are transmitted also to the STUK’s emer- the possibility of several reactor units’ simultane- gency response centre. The automatic data transfer ous accident in the emergency planning. In STUK’s and display system from the Olkiluoto NPP to decisions made on the basis of the national as- STUK was upgraded in 2011 and from the Loviisa sessments and European Stress Tests for nuclear NPP to STUK in 2012. power plants, both TVO and Fortum were required Emergency response training and exercises are to clarify and update their emergency plans and annually arranged for the emergency response procedures with respect to issues like qualification organisation of the nuclear power plants. The of the staff in the emergency organisation, man- emergency response training has included class- agement of access control and contamination con- room and group-specific practical training as well trol in the case when the normal arrangements are as special training, such as first aid, fire and -ra out of function and restoring the access routes and diation protection training. In addition to severe connections to the site in case of massive destruc- accidents, emergencies covered by the emergency tion of the infrastructure. Loviisa and Olkiluoto response exercises also included conditions classi- NPP as well as STUK’s emergency centre are now fied as emergency standby. The content and scope equipped with satellite telephones. The work for of the training as well as feedback obtained from developing and improving the emergency prepar- the training are assessed in the inspections of the edness arrangements will continue. STUK’s periodic inspection programme. Fortum and TVO have analysed accident STUK verifies the preparedness of the organisa- and safety-impairing events at the Loviisa and tions operating nuclear power plants in yearly on- Olkiluoto NPPs. These analyses are documented in site inspections. Emergency preparedness at the the safety analysis reports of the plants and have Loviisa and Olkiluoto power plants meet the key been used as the basis for planning the Finnish regulatory requirements. At the Loviisa NPP, the nuclear power plant emergency response arrange- objects of the inspection included the preparedness ments. organisation’s personnel resources, facilities and Emergencies are classified and described briefly equipment, training and alert arrangements, revi- in the plant’s emergency plan. The notifications sion of the structure and content of emergency pre- and alarms to plant personnel and authorities paredness instructions, radiation measurements required by different classes of emergencies, as in the surroundings and meteorological measure- well as the scope of operations of the emergency re- ments on-site. Emergency preparedness exercises sponse organisation pertaining to the type of emer- and mustering exercises were conducted annually. gency, are described in the emergency procedures. Also an unannounced exercise was organised start- A person responsible for emergency response ing outside the normal working hours. arrangements has been appointed both for the At the Olkiluoto NPP, the objects of the inspec- Loviisa and Olkiluoto nuclear power plants. Due tion included preparedness organisation personnel to the updated Nuclear Energy Act the nominated resources, training, exercises, facilities and equip- deputies for the persons responsible for emergency ment, alarm arrangements, radiation measure- response arrangements have been appointed by ments in the surroundings, meteorological meas- the licensees and approved by STUK. The emer- urements on-site, emergency preparedness of the gency response organisation has been described Olkiluoto unit 3 construction site and the work for in the emergency plan and procedures, updated revising the emergency preparedness instructions. with regard to personnel changes once a year. The An all-site mustering exercise was held in 2012 at more limited staffing of the emergency response the Olkiluoto unit 3 construction site. organisation required for emergency standby state Both the Loviisa and Olkiluoto monitoring net- (alert) is defined in the shift supervisor guides for works have up to 15 real time environmental dose the emergency response. rate measuring stations, five and four of them close

57 STUK-B 164 Article 16 – Emergency preparedness to the plant area and the others in a half circle at The off-site plans include provisions to inform 5 km distance from the plant. Three additional the population in the case of an accident. Written measurement stations will be installed in the vi- instructions on radiological emergencies, emergen- cinity of Olkiluoto unit 3 before the plant unit is in cy planning and response arrangements have been operation. At the Loviisa NPP, a new monitoring provided to the population living within the 20 km network including 28 stations is on trial run and Emergency Planning Zone. These instructions are will replace the older system in 2013. The design regularly updated and distributed. basis of the new measuring stations is at least 3 The regulations and guides are tested in off-site months autonomic operation in emergency situa- emergency exercises conducted every third year. tions with long-term batteries. At the Loviisa NPP, Full scale off-site emergency and rescue exercise the licensee will renew the weather monitoring OLKI11 was carried out in 2011 based on the system including also the on-site weather mast Olkiluoto nuclear power plant accident scenario. and including a new measurement point in the Over 50 different organisations participated in this marine environment. exercise which combined for the first time a sce- nario initiated by illegal activities and a technical Off-site preparedness arrangements emergency situation at the plant. In addition to the on-site emergency plans estab- In 2013, the national full command post exer- lished by the licensees, off-site emergency plans re- cise LOVIISA13 was held. About 60 different gov- quired by the rescue legislation (379/2011) are pre- ernmental, regional and private organisations in pared by regional authorities. The requirements Finland took part in the exercise. for off-site plans and activities in a radiation emer- As a result of the studies made after the gency are provided in the Decree of the Ministry TEPCO Fukushima Dai-ichi accident, no major of Interior (406/2011). STUK is an expert body to support the Ministry of Interior in the emergency response in the case of nuclear and radiological ac- cidents. STUK publishes VAL Guides for emergency re- sponse. Guide VAL 1 (2012) “Protective Measures in Early Phase of a Nuclear or Radiological Emergency” and VAL 2 (2012) “Protective Measures in Intermediate Phase of a Nuclear or Radiological Emergency” provide detailed guidance. In the case of an accident the local authorities are alerted by the operating organisation of the plant. The Ministry of Interior has released a new guide “Nuclear or Radiological Emergencies: Roles and Responsibilities of All Actors” (MI publication 38/2012), which contains the detailed information of the arrangements in the Finnish society in the case of a nuclear or radiological emergency. STUK has an Emergency Preparedness Manual for its own activities in the case of a nuclear or ra- diological emergency. STUK has an expert on duty on 24/7 basis. The message on an exceptional event (alarm) can be received from the operating organi- sations of the facilities, or automatically from the radiation monitoring network that is dense in the whole country (approx 250 measuring stations, see Figure 17), or from foreign authorities. Figure 17. The measuring stations of the radiation monitoring network.

58 Article 16 – Emergency preparedness STUK-B 164 changes have been identified in off-site emergency necessary evaluation of the emergency in a timely preparedness so far. However, there is a need to manner and to provide appropriate recommenda- ensure accessibility to the site in case of extreme tions for protective measures. The organisation natural hazards, provide a sufficient amount of ra- and conduct of the emergency exercises and the diation protection equipment and radiation moni- coordination with other stakeholders was also con- toring capabilities for rescue services and improve sidered exemplary. communication capabilities. In addition, there is a need to ensure that the resources of rescue au- Information to the neighbouring countries thorities can be reasonably coordinated between Finland is a party to the Convention on Early radiological and other emergencies, should they Notification of a Nuclear Accident and the happen simultaneously. Convention on Assistance in the Case of a Nuclear The rescue planning is strengthened in a co-op- Accident or Radiological Emergency, done in eration between the nuclear power plant, regional Vienna in 1986. Being a member of the European rescue services, regional police departments and Union, the Council Decision (87/600/EURATOM) STUK. Permanent coordination groups have been on Community arrangements for the early ex- established for both Loviisa and Olkiluoto NPPs change of information in the event of a radiologi- in order to ensure coordinated and consistent cal emergency applies in Finland, too. In addition, emergency plans, to improve and develop emer- Finland has respective bilateral agreements with gency planning and arrangements and to share Denmark, Germany, Norway, Russia, Sweden and lessons from the exercises, regulations and other Ukraine. Accordingly, arrangements have been information. Also extensive training is arranged agreed to directly inform the competent authorities by these groups. In addition, a National Nuclear of these countries in the case of an accident. Power Plant Emergency Preparedness Forum is In addition to the domestic nuclear emergency under consideration in order to have co-operation exercises held annually on each nuclear power and combination between permanent groups. The plant site, STUK has taken part in international Ministry of the Interior and the Ministry of Social emergency exercises. STUK has also participated Affairs and Health, the regional rescue service as a co-player in emergency exercises arranged authorities, STUK and the NPP licensees will be by the Swedish and Russian nuclear power plant participating in the Forum. operators and authorities. Neighbouring countries In autumn 2012, an international Integrated have been actively invited to take part in the Regulatory Review Service (IRRS) mission held Finnish exercises. In 2013, Finland hosted a joint at STUK covered also emergency arrangements. international exercise in which Nordic and Baltic As the outcome, the IRRS mission suggested countries and the IAEA took part in. Participants that STUK should, in cooperation with relevant were from Sweden, Norway, Denmark, Iceland, Government authorities, consider improving na- Estonia, Latvia, and Lithuania and also Russian tional arrangements for timely provision of as- key emergency centres followed the exercise. The sistance requested by other countries (including international exercise was combined with the full through RANET) and for effectively integrating exercise at the Loviisa nuclear power plant. In the assistance received by Finland into the national exercise e.g. real time communication and coordi- response system. As a good practise the IRRS team nation of actions among participants were tested. mentioned that STUK has excellent tools, facilities In conclusion, Finnish regulations and practices and organisational arrangements to perform the are in compliance with Article 16.

59 STUK-B 164

Article 17. Siting complies with the EU Directive 2001/42/EU on the Each Contracting Party shall take the appro- EIA procedure. priate steps to ensure that appropriate proce- In the design of a nuclear power plant, site- dures are established and implemented: related external events have to be taken into ac- i. for evaluating all relevant site-related fac- count. Government Decree 733/2008 provides as tors likely to affect the safety of a nuclear follows: “The safety impact of local conditions, as installation for its projected lifetime; well as the security and emergency preparedness ii. for evaluating the likely safety impact of a arrangements, shall be considered when selecting proposed nuclear installation on individu- the site of a nuclear power plant. The site shall be als, society and the environment; such that the impediments and threats posed by iii. for re-evaluating as necessary all relevant the facility to its environment remain extremely factors referred to in sub-paragraphs (i) minor and heat removal from the plant to the en- and (ii) so as to ensure the continued safety vironment can be reliably implemented.” STUK acceptability of the nuclear installation; issued in 2001 the Guide YVL 1.10 “Safety criteria for consulting Contracting Parties in the for siting a nuclear power plant”, which describes vicinity of a proposed nuclear installation, generally all requirements concerning the site insofar as they are likely to be affected by and surroundings of a nuclear power plant, gives that installation and, upon request provid- requirements on safety factors affecting site selec- ing the necessary information to such Con- tion and covers regulatory control. Requirements tracting Parties, in order to enable them to on seismic design are set forth in the Guide YVL evaluate and make their own assessment of 2.6. Deterministic analyses are made to assess the the likely safety impact on their own terri- impact of various natural phenomena and other tory of the nuclear installation. external events. The probabilistic risk assessment required for the safety review of Construction and Regulatory approach to siting Operating Licence applications provides informa- Requirements for the siting of a nuclear power tion on risks caused by external events. plant are provided in the Nuclear Energy Act and The general principle in the siting of nuclear the Nuclear Energy Decree. The application for a power plants is to have facilities in a sparsely Decision-in-Principle has to include e.g.: populated area and remote from large population • a description of settlement and other activities centres. In the vicinity of the plant, no activities and town planning arrangements at the site are allowed that could pose an external threat to and its vicinity the plant. Site characterisation is performed based • a description of the suitability of the planned on geological, seismic, hydrological and meteoro- location for its purpose, taking account of the logical factors as well as on transport routes and impact of local conditions on safety, security risks, industrial activities, agriculture, nature and and emergency response arrangements, and the population. Extreme meteorological conditions and impacts of the nuclear facility on its immediate consequences (e.g. frazil ice formation) have to be surroundings taken into consideration in the site evaluation and • an assessment report in accordance with the plant design. Act on the Environmental Impact Assessment In connection with the decisions for construc- Procedure (468/1994) as well as a description of tion of the Loviisa and Olkiluoto plants in the the design criteria which the applicant will ob- 1970s, siting requirements related to population serve in order to avoid environmental damage density and land use planning were quite easily and to restrict the burden to the environment. and practically achievable in a sparsely populated country like Finland. The precautionary action More detailed requirements on the Environmental zones have only a few tens of permanent inhabit- Impact Assessment (EIA) are provided in the ants. Similar attention was not given to the recrea- Decree on Environmental Impact Assessment tional houses and the transient summertime popu- Procedure (713/2006). The Finnish EIA legislation lation in the coastal area (mainland and islands)

60 Article 17 – Siting STUK-B 164 where the conditions might be demanding for ef- ties. In the a specific statement is ficient emergency preparedness and rescue action. also prepared for each new nuclear power plant The number of recreational houses on the seaside unit in a member state before authorisation of within 5 km the existing plants is about 400–500. the operation (Euratom Treaty, Article 37). This is Finland is a party to the Convention on based on a General Data report submitted by the Environmental Impact Assessment in a member state and on its examination in a plenary Transboundary Context, done in Espoo in 1991. meeting of Group of Experts. For Olkiluoto unit 3 The Convention is applied for Finnish nuclear this process was conducted in 2010. Based on the facility projects by providing a full participation legislation on land use planning, statements from to all neighbouring countries which announce the neighbouring countries must be requested for the willingness to participate in the environmental im- land use plans of a nuclear power plant. Sweden, pact assessment procedure in question. In Finland, Denmark, Norway, Germany, Poland, Lithuania, the EIA is conducted at an early stage of a NPP Latvia and Estonia were informed of initiating the project, prior to the selection of the plant design, regional planning process for Fennovoima’s two based on the power range of the plant and on gen- candidate sites in Northern Finland and the oppor- eral information on the available designs. This is tunity to participate. before the Decision-in-Principle is taken, as the The detailed requirements on the determina- outcome of the EIA procedure is part of the materi- tion of site-specific design bases for external events al needed for the Decision-in-Principle application. are collected and expanded in the new Guide YVL Regulatory Guide YVL 1.10 on NPP siting cri- B.7. teria is being revised. The new Guide YVL A.2 will include a description of all relevant legal processes, Re-evaluation of site related factors including those based on non-nuclear legislation. The operating licence for a nuclear facility is grant- Efficient cooperation between the utility and re- ed for a fixed term. Periodic Safety Review (PSR) sponsible authorities is emphasised, e.g., for: shall be conducted either in connection with the • maintaining the land use planning in the plant license renewal or as a separate review with inter- environment during the plant operational life vals of about ten years at most. time in line with the safety goal of avoiding For the licence renewal of the Loviisa units in dense population 2005–2007 and the Periodic Safety Review of the • taking necessary actions to guarantee efficient Olkiluoto units in 2007–2009, comprehensive re- road connections to the plant area also in case assessments of safety, including the environmen- of a severe accident and all extreme weather tal safety of the nuclear facility and the effects of conditions. external events on the safety of the facility, were conducted by the licensees and reviewed by STUK. Quality, competence and comprehensiveness of the The assessments covered meteorology, hydrology, site survey and site confirmation are required and geology, seismology, population and use of land the results shall be assessed by STUK in differ- and sea area. During the operation of a nuclear ent licensing stages. The basic goals for population facility, the Final Safety Analysis Report (FSAR), safety will not be changed in the revised guide. including its site-specific parts, has to be periodi- The EIA and other site-related studies are con- cally reviewed and updated as needed. A detailed ducted by the licence applicant or licensee depend- re-evaluation of the site related factors was also ing on the context. The safety related reports are carried out in 2007–2009 for the Olkiluoto and reviewed by STUK. The Ministry of Employment Loviisa sites in connection with the Environmental and the Economy arranges the national public Impact Assessment and Decision-in-Principle pro- hearings and the Ministry of the Environment ar- cedures for new NPP units. The next PSR for the ranges the international hearings. Loviisa NPP has been started by the licensee and The bilateral agreements mentioned under it shall be submitted to STUK by the end of 2015. Article 16 include provisions to exchange informa- The next PSR for the Olkiluoto NPP units 1 and 2 tion on the design and operation of nuclear facili- will be conducted in connection with the renewal of

61 STUK-B 164 Article 17 – Siting the operating licences expiring at the end of 2018. action was recognized, but some additional studies Olkiluoto site related factors will be re-evaluated of external hazards and feasibility studies for plant also in connection with the operating licence proce- modifications to improve robustness against exter- dure for the Olkiluoto unit 3. nal events were found justified. The capacity of the NPP units to withstand ex- The following examples of safety improvements ternal hazards is evaluated in deterministic safety and additional analyses of external events at the analyses and in probabilistic risk assessments Loviisa NPP can be mentioned: enhanced protec- (PRA). PRAs of the Finnish units cover natural tion against high seawater level during annual and man-made external hazards such as high maintenance shutdown (partly implemented) and seawater level, high wind including tornadoes, power operation (hazard evaluation and feasibility lightning, high- and low air temperature, high sea- studies on-going), installing cooling towers replac- water temperature, frazil ice formation in cooling ing the service water system in case of blockage water intakes, algae and other organic material in of seawater intake (under detailed planning), and seawater, oil spills from oil tanker ship accidents detailed structural analysis of spent fuel pools in and earthquakes. During the past twenty years the case of an earthquake with consequential boil- the results of external events PRAs have initiated ing in the pools. several safety improvements in the plants. At the Olkiluoto NPP units 1 and 2, the plans Research on the site related natural hazards include system modifications to ensure the opera- is conducted continuously in the Finnish National tion of the auxiliary feed water system in case of Nuclear Safety Research Program SAFIR (http:// the loss of the ultimate heat sink (seawater sys- safir2014.vtt.fi/links.htm). STUK has a major role tems) and structural analysis of the spent fuel in steering the research and the results support pools. Seismic walk-downs of the fire extinguishing STUK in the review of the reports submitted by water system have been carried out and some im- the licensees. The research covers seismic haz- provements will be implemented. The emergency ard and extreme meteorological phenomena and diesel generators will be replaced within the next seawater level variations, including the effects of few years. The new emergency diesel generators climate variability and change. will be provided with alternative air and seawater In addition to the normal PSRs, an extraordi- cooling, while the existing diesels have only sea- nary review of site related issues was carried out water cooling. In addition, studies are carried out after the TEPCO Fukushima Dai-ichi accident on systems to ensure residual heat removal in the in connection with the so called European stress case of total loss of AC power and/or loss of the ul- tests. National studies were initiated immediately timate heat sink due to external or internal events. after the accident and the EU stress tests were The effects of extreme seawater levels on the acces- started in June 2011. sibility of the site will be studied as well. The stress tests did not reveal any new site- In conclusion, Finnish regulations and practices related external hazards or vulnerabilities of the are in compliance with Article 17. plants to external events. No need for immediate

62 STUK-B 164

Article 18. Design and construction Dispersion of radioactive materials from the Each Contracting Party shall take the appro- fuel of the nuclear reactor to the environment shall priate steps to ensure that: be prevented by means of successive barriers which i. the design and construction of a nuclear are the fuel and its cladding, the cooling circuit of installation provides for several reliable the nuclear reactor and the containment building. levels and methods of protection (defence Provisions for ensuring the integrity of the fuel, in depth) against the release of radioac- primary circuit and containment are included. tive materials, with a view to preventing In ensuring safety functions, inherent safety the occurrence of accidents and to mitigat- features attainable by design shall be made use of ing their radiological consequences should in the first place. If inherent safety features cannot they occur; be made use of, priority shall be given to systems ii. the technologies incorporated in the de- and components which do not require an external sign and construction of a nuclear instal- power supply or which, as a consequence of a loss lation are proven by experience or quali- of power supply, will settle in a state preferable fied by testing or analysis; from the safety point of view (passive and fail-safe iii. the design of a nuclear installation al- functions). lows for reliable, stable and easily manage- In order to prevent accidents and mitigate the able operation, with specific consideration consequences thereof, a nuclear power plant shall of human factors and the man-machine be provided with systems for shutting down the interface. reactor and maintaining it in a subcritical state, for removing decay heat generated in the reactor, Implementation of defence in depth and for retaining radioactive materials within the plant. Principles ensuring the implementation of Regulatory requirements regarding nuclear these safety functions even in the event of a mal- power plant design and construction function must be applied in designing the systems According to the Government Decree 733/2008, in question. Such principles are redundancy, sepa- several levels of protection have to be provided in ration and diversity. The safety functions neces- the design of a nuclear power plant. The design of sary for transferring the plant to, and maintaining the nuclear facility and the technology used is as- a controlled state must be accomplished, even if sessed by STUK when reviewing the applications any individual system component needed to fulfil for a Decision-in-Principle, Construction Licence the safety function (including the necessary sup- and Operating Licence. Design is reassessed porting or auxiliary functions) is inoperable and against the advancement of science and technol- if any other component needed for the function is ogy, when the Operating Licence is renewed and in simultaneously out of use due to required repair the periodic safety reviews. or maintenance. Common-cause failures in safety In the design, construction and operation, prov- systems shall only have minor impacts on plant en or otherwise carefully examined high qual- safety. A nuclear power plant shall have reliable ity technology shall be employed to prevent op- on-site and off-site electrical power supply systems. erational transients and accidents and to mitigate The execution of safety functions shall be possible their consequences. A nuclear power plant shall by using either of the two electrical power supply encompass systems by means of which operational systems. Due to the TEPCO Fukushima Dai-ichi transients and accidents can be quickly and reli- accident, the Finnish requirements are being sup- ably detected and the aggravation of any event plemented by requiring that the plant shall be pro- prevented. Effective technical and administrative vided with systems and procedures by which decay measures shall be taken for the mitigation of the heat removal from the reactor and from the spent consequences of an accident. The design of a nucle- fuel pools can be ensured for 72 hours independ- ar power plant shall be such that accidents leading ent of the electricity or water supply from off-site to extensive releases of radioactive materials must sources in events caused by rare external events be highly unlikely. or disturbances in the plant internal electricity distribution.

63 STUK-B 164 Article 18 – Design and construction

The plant shall also be provided with systems, In connection with the Loviisa plant’s licence structures and components for controlling and renewal, Fortum prepared a plan on actions aimed monitoring severe accidents. These shall be inde- at further enhancing the safety of the plant units pendent of the systems designed for operational in the future. The most important ongoing plant conditions and postulated accidents. Systems nec- modification project related to the Defence-in- essary for ensuring the integrity of the contain- Depth concept at the Loviisa plant is the upgrade ment building in a severe accident shall be safety- of the I&C systems of the plant units. The project classified and capable of performing their safety started in 2004 with the construction of a new I&C functions, even in the case of a single failure of an building. Safety classified parts of the project are active component. intended to be completed in 2017. Special attention shall be paid to the avoid- Fortum and TVO have also reviewed all of the ance, detection and correction of any human er- analyses of transient and accident situations at rors during design, construction, operation and the Loviisa and Olkiluoto nuclear power plants in maintenance. The possibility of human errors shall connection with the operating licence renewal and be taken into account in the design of the nuclear periodic safety review. Deterministic safety assess- power plant and in the planning of its operation ment is described in more detail under Article 14. and maintenance, so that human errors and devia- Severe accidents were not taken into account in tions from normal plant operations due to human the original design of the operating Finnish nucle- errors do not endanger plant safety. The impacts ar power plants. However, since the commissioning of human error shall be reduced by using various of the plants, major improvements have been im- safety design methods, including defence-in-depth, plemented to mitigate the consequences of severe redundancy, diversity and separation. accidents. Mitigations systems of the Loviisa and Detailed requirements are given in Guides YVL Olkiluoto NPPs are described in detail in Annexes 1.0, YVL 2.0, YVL 2.4, YVL 2.7, YVL 3.0, YVL 4.3, 2 and 3. YVL 5.2, YVL 5.5, and YVL 6.2. For the Olkiluoto unit 3, application of the An assessment of the design of the facility and Defence-in-Depth principle was presented in the related technologies is made by STUK for the first Preliminary Safety Analysis Report (PSAR). The time when assessing the application for a Decision- design follows the principles laid down in the in-Principle. Later on, the evaluation is continued Government Decree 733/2008. Compared with the when the Construction Licence application is re- existing reactors, the possibilities for mitigation viewed. Finally, the detailed evaluation of systems of the consequences of the severe accidents are and equipment is carried out through their de- taken into account already in the early design sign approval process. The design of Loviisa plant phase. This is achieved by implementing features units was reassessed by STUK in 2005–2007 and to ensure containment integrity. Design provisions Olkiluoto plant units in 2007–2009 in the periodic include e.g. core catcher for corium spreading and safety review process. Design of the Olkiluoto unit cooling, hydrogen recombination, and containment 3 has been assessed for the construction licence heat removal. In addition, aircraft crash protection (2005) and during the construction phase. It will be design requirements for both a military aircraft reassessed when reviewing the plant’s operating and a large passenger aircraft are taken into ac- licence. count. Several plant modifications improving safety Application of defence in depth have been carried out at the Loviisa NPP during concept at the Finnish NPPs the last few years. Plates preventing vortices were During the time period 2010–2012, no significant installed in the intake pipes of the Loviisa plant faults or signs of wear were detected in the integ- emergency makeup water tanks during the 2009 rity of equipment and structures critical to plant annual outage. The objective of the modification is safety. The condition of the multiple barriers con- to obstruct air suction into the reactor emergency taining releases of radioactive substances has re- injection system pumps when the tank water level mained good both at the Loviisa and Olkiluoto drops. The Loviisa plant improved suction strain- NPPs. ers of the low pressure emergency cooling system

64 Article 18 – Design and construction STUK-B 164 and the containment spraying system by means of • Design plans of diverse cooling water supply installing higher density mesh elements in them. to the spent fuel pools have been submitted to The modification serves to ensure fuel cooling in STUK in 2013. accident conditions by means of preventing materi- • Evaluation of the availability of cooling water als coming loose from, for example, heat insulation and emergency diesel fuel in case of accidents from being carried to the reactor core via the emer- at multiple units. gency cooling system. According to analyses, block- ages in the core caused by large amounts of fibres Fukushima related modifications at the Loviisa could lead to overheating of the reactor core. The NPP are described in more detail in Annex 2. modifications were carried out at the Loviisa unit 2 Several plant modifications improving safety in 2010 and at the Loviisa unit 1 in 2011. have also been carried out at the Olkiluoto NPP Based on the safety analyses, it was considered units 1 and 2 during the last few years. The main necessary to make modifications in the operation steam line isolation valves inside the containment of the Loviisa emergency water tanks of the low were replaced at the Olkiluoto units 1 and 2 dur- pressure emergency cooling system (accumula- ing annual maintenances in 2010 and 2011. The tors). The modification serves to to ensure that function of the valves is to isolate the reactor pres- heat transfer from the reactor can be reliably pro- sure vessel and prevent the loss of reactor coolant vided by preventing the nitrogen in the water tank and releases of radioactive substances outside the from getting into the reactor. In order to ensure containment. The valves also function as a backup the tightness of the primary circuit, the sealing for the isolation valves outside the containment. grooves of two inner sealing groove zones of the One reason for the valve replacement was the ten- Loviisa units 1 and 2 reactor pressure vessel flange dency of the old valves to close as the steam flow face were repaired. The tightness of the reactor increases. In a situation where one valve closes, the pressure vessel and its lid is based on double seal steam flow through the other valves increases and grooves in which a nickel sealing wire is inserted. this can make them close, too. The near simultane- The first defects which required local repair were ous closing of all the steam line isolation valves detected in these sealing grooves in periodic in- causes a greater pressure rise and load on the spections at the Loviisa unit 2 in 2005. Similar de- reactor pressure vessel than the closing of a single fects were also detected in subsequent inspections valve only. at the Loviisa unit 1. The repairs were done during TVO has replaced in 2010 all rubber collar pipe the annual outage 2010 at the unit 1 and 2012 at penetrations below elevation +10 in the rooms the unit 2. containing emergency cooling system pumps with Due to the TEPCO Fukushima Dai-ichi acci- type-approved fire and pressure penetrations. All dent, safety improvements have been initiated at in all, the modification involved over 60 penetra- the Loviisa NPP. Improvements under planning tions. STUK had earlier made a remark about the and implementation for the Loviisa plant include condition of the penetrations. TVO examined all among other things: the similar original penetrations at the plant by • Installation of independent cooling towers for means of testing and assessing their compliance decay heat removal from the reactor core and with fire, ventilation and water-tightness require- from the spent fuel pools. The cooling towers ments, and analysed the risks to plant safety. would provide an alternative ultimate heat sink Based on the risk analysis results, the impact of in case of loss of sea water cooling. Installation the conditions of the penetrations was about 3% of of the towers is planned for 2014. the PSA model annual core damage frequency. • Flood protection. The utility has estimated the TVO has made a decision to replace all cur- effects of high sea level to the plant behav- rent emergency diesel generators (EDGs) of the ior. The utility will submit a detailed plan of Olkiluoto units 1 and 2 with their auxiliary sys- improved flood protection in 2014 (protection tems to correspond with the changed need for during annual maintenance shutdown already power, taking also into account any increases in partly implemented). the need for power due to possible future plant

65 STUK-B 164 Article 18 – Design and construction

modifications as well as the lessons learnt from at the Olkiluoto unit 1 about one week before the Fukushima accident in relation to securing the the 2010 annual maintenance. The leak remained power supply. small, and the leaking fuel assembly was removed Safety improvements due to the TEPCO from the reactor during the outage. Olkiluoto unit Fukushima Dai-ichi accident under planning for 2 had two fuel leaks in 2010–2011. The leaking fuel the Olkiluoto units 1 and 2 include among other assemblies were identified and removed from the things: reactor during the 2011 and 2012 annual mainte- • Assessing possibilities for ensuring cooling of nances. the reactor core in case of total loss of AC sup- Inspections of the reactor pressure vessel and plies and systems. Evaluations of feasible solu- piping have revealed no deterioration of the ma- tions are under way. terials at the Finnish NPPs. No significant issues • Ensuring operation of the auxiliary feed water with safety implications were observed in the peri- system pumps independently of availability of odic inspections of the pressure equipment. STUK the sea water systems. The modification is has renewed the operating licences of the Loviisa planned for 2014-2015. units 1 and 2 reactor pressure vessels until the • Design plans of diverse cooling water supply to end of the operating licence of the units. However, the spent fuel pools will be completed in 2013. safety of the pressure vessel operation must be • The utility is assessing plans for new mobile assessed in connection with the Periodic Safety equipment (aggregates, pumps). Reviews. • Evaluation of the availability of cooling water The Loviisa unit 2 primary and secondary cir- and emergency diesel fuel in case of accidents cuits were subjected to pressure tests in 2010. The at multiple units. pressure tests are performed every eight years. In the tests, the structural strength and leak tight- Fukushima related modifications at the Olkiluoto ness of the circuits are tested using a pressure NPP units 1 and 2 are described in more detail in 1.3 times the design pressure, i.e. 178 bar abs for Annex 3. the primary circuit and 73 bar abs for the second- In 2011, STUK has accepted increase of the ary circuit. Results of the tests were accepted by maximum bundle average burnup up to 57 MWd/ STUK. The inner parts of the reactor pressure kgU for the TVEL 2nd generation fuel used at the vessel of the Olkiluoto unit 1 were subjected to a Loviisa plant. STUK has also accepted increase visual video inspection during the 2011 refuelling of the maximum bundle average burnup up to 50 outage. The Olkiluoto unit 1 faults being monitored MWd/kgU for the fuel types used at the Olkiluoto have remained unchanged, and the inspections did units 1 and 2: GEI4, GNF2, ATRIUM 10XM, SVEA- not reveal any new faults with important safety 96 OPTIMA and SVEA-96 OPTlMA2. New type of implications. fuel bundles (so-called TVEL 2nd generation fuel) The steel liner of the Loviisa NPP containment were taken into use at the Loviisa NPP in 2009. is subjected to a leak tightness test at four-year The fuel enrichment is slightly higher which has intervals using the design pressure of 1.7 bar an impact on shutdown margin of the reactor. Also abs. The test has been carried out in 2010 at the six rods in the bundle contain burnable poison. Loviisa unit 2 and in 2012 at the Loviisa unit 1. Acceptable control rod positions in the Operational Results of the tests have fulfilled the acceptance Limits and Conditions were also changed in order criteria. The reactor containment at the Olkiluoto to keep the shutdown margin of the reactor core at NPP is subjected to a leak tightness test three the same level as before. times during a 12-year period. In addition, leak A minor fuel leak was observed at the Loviisa tightness tests have been made systematically to unit 1 on 2009. One leaking fuel assembly was containment isolation valves, personnel airlocks found in the investigation carried out during and containment penetrations during the annual the annual maintenance outage of 2010, and the outages. The results show that the leak tightness leaking assembly was removed from the reactor. of the containment building has remained accept- Another minor fuel leak has been observed at the able at the both NPPs. The overall leak tightness Loviisa unit 2 late 2012. A fuel leak was observed of the Olkiluoto unit 2 reactor containment was

66 Article 18 – Design and construction STUK-B 164 tested during the annual outage of 2010 and that quality technology shall be employed in the de- of the Olkiluoto unit 1 containment during the out- sign, construction and operation of a nuclear power age of 2012. Results of the test have fulfilled the plant. The respective detailed requirements are acceptance criteria. provided in many YVL Guides. During the period 2010–2012, no significant Practical implementation of the new safety failures were observed at the Loviisa plant in the requirements and procedures to ensure adequate safety functions or in the systems, equipment and reliability of software based instrumentation and structures executing them. No significant faults or control systems in the modernisation projects of signs of wear have been detected during in the in- the operating power plants and in the design of tegrity of equipment or structures critical to plant the new nuclear power plant can be considered as safety. one of the major challenges for the next years. This In accordance with a periodic testing pro- includes also the issues related to the highly inte- gramme, TVO carried out testing of the relief train grated control rooms. valves of the blowdown system at the Olkiluoto At the Loviisa NPP, I&C systems are currently unit 1 during the 2010 annual maintenance. The being renewed. The project began in 2002 with purpose of the blowdown system is to limit the basic conceptual design; implementation begun in pressure in the reactor by letting out steam from 2004 with construction of new buildings to accom- the reactor to the suppression pool if the normal modate the new systems. Safety classified parts of route of the steam to the turbine is not available. the project are intended to be completed in 2017. When tested, two relief valves did not operate as The first phase was implemented at the Loviisa planned. TVO carried out inspection of the electric unit 1 during the 2008 annual maintenance, in- pilot valves of the relief valves which revealed that cluding the upgrade of I&C of reactor preventive three electric pilot valves had jammed. All three and control rod position measurement and control jammed valves were of a new type that had been functions, part of reactor in-core monitoring sys- installed at the Olkiluoto unit 1 the year before. tem and I&C of some non-safety auxiliary systems. The reason for the jamming was the oxidation of Control room facilities are also renewed in phases the internal coating material of the valve guide with the system renewal. bushing. The manufacturer had changed the coat- At the Olkiluoto units 1 and 2, changes in I&C ing material without informing TVO. systems are made gradually. Software based in- In 2011 maintenance outage at the Olkiluoto strumentation and control technology has already unit 2, TVO discovered that there were cracks in been implemented in the modernised systems. The the pistons of the blowdown system valves. The safety systems, with the exception of new protec- inspections revealed other damage as well; for tive relays of electrical systems and neutron flux example, the hard chrome plating of the pilot cyl- measurement system, are still of conventional inder had been damaged. However, the cracks and technology. other damage had not affected the operation of STUK has reviewed the licensing documents the valves; they had operated correctly in periodic related to the modernisation project of the Loviisa tests. TVO replaced the parts of the worst damaged units 1 and 2 and the construction project of the valves during the annual maintenance. Based on Olkiluoto unit 3. The licensing path covers differ- the requirement by STUK, new spare parts were ent layers of the design from architectural design changed to the valves immediately when a suffi- of I&C (including Defence-in-Depth, separation cient number of new spares had been received from and diversity assessments) to system level design the manufacturer. STUK also required that TVO and down to I&C platform and equipment suit- must inspect the similar valves at the Olkiluoto ability and licensing. During the licensing, STUK unit 1. The events are described in more detail in is reviewing that proven and qualified solutions Annex 3. are used. The critical part of the licensing is how to dem- Incorporation of proven technologies onstrate that the prevention of failure propagation It is stated in the Government Decree 733/2008 and independency of different defence-in-depth that proven or otherwise carefully examined high- levels are adequate. Proofing that platforms and

67 STUK-B 164 Article 18 – Design and construction equipment fulfils requirements can also be labo- man errors shall be taken into account both in the rious work and must be carefully planned if the design of the nuclear power plant and in the plan- equipment is not originally designed for safety ning of its operation so that the plant withstands critical use. Cyber security threats must also be well errors and deviations from planned opera- considered. tional actions. Plant systems reliability and human factors Design for reliable, stable and are systematically considered in the probabilistic manageable operation risk assessments (PRA). The analyses support the Government Decree 733/2008 requires that a nu- efforts to eliminate accidents or to mitigate their clear power plant’s control room shall contain consequences. The probabilistic risk assessments equipment which provide information about the are subject to the approval of STUK. Human fac- plant’s operational state and any deviations from tors in relation to the monitoring and control of normal operation as well as systems which moni- Finnish nuclear power plants area described under tor the state of the plant’s safety systems during Article 12. Significant effort has been devoted by operation and their functioning during operational the regulator and utilities involved in the assess- transients and accidents. Furthermore, it requires ment of modern control room concepts. Existing that a nuclear power plant shall contain automatic plants are moving towards so-called hybrid control systems that maintain the plant in a controlled rooms, where normal operation is based on digital state during transients and accidents long enough controls and video screens, but safety backups are to provide the operators a sufficient time to con- still implemented also using traditional mosaic sider and implement the correct actions. Special displays, analogy indicators and switches. attention shall be paid to the avoidance, detection In conclusion, Finnish regulations and practices and repair of human errors. The possibility of hu- are in compliance with Article 18.

68 Article 19 – Operation STUK-B 164

Article 19. Operation Initial authorisation Each Contracting Party shall take the appro- According to Government Decree 733/2008 Section priate steps to ensure that: 22, in connection with the commissioning of a nu- i. the initial authorization to operate a nu- clear power plant, the licensee shall ensure that clear installation is based upon an appro- the systems, structures and components and the priate safety analysis and a commissioning plant as a whole operate as designed. At the com- programme demonstrating that the instal- missioning stage, the licensee shall ensure that an lation, as constructed, is consistent with expedient organisation is in place for the future design and safety requirements; operation, alongside a sufficient number of quali- ii. operational limits and conditions derived fied personnel and instructions suitable for the from the safety analysis, tests and opera- purpose. tional experience are defined and revised Requirements for the commissioning pro- as necessary for identifying safe bounda- gramme are set forth in the Guide YVL 2.5. ries for operation; According to the Guide YVL 2.5, the purpose of the iii. operation, maintenance, inspection commissioning programme is to give evidence that and testing of a nuclear installation are the plant has been constructed and will function conducted in accordance with approved according to the design requirements. Through procedures; the programme possible deficiencies in design and iv. procedures are established for re- construction can also be observed. The Operating sponding to anticipated operational occur- Licence is needed before fuel loading into the reac- rences and to accidents; tor. Authorisation for fuel loading is given by STUK v. necessary engineering and technical sup- after its specific inspection where readiness of the port in all safety-related fields is available power plant and operating organisation is checked. throughout the lifetime of a nuclear instal- Furthermore, according to the Nuclear Energy lation; Decree, the various steps of the commissioning, i.e., vi. incidents significant to safety are re- criticality, low power operation and power ascen- ported in a timely manner by the holder of sion, are subject to the approval of STUK. the relevant licence to the regulatory body; The commissioning programme is described in vii. programmes to collect and analyse op- the Preliminary and Final Safety Analysis Reports. erating experience are established, the re- The participation of the operating staff in the com- sults obtained and the conclusions drawn missioning programme is a requirement of the are acted upon and that existing mecha- Guide YVL 1.6. The commissioning programme is nisms are used to share important experi- to be submitted to STUK for approval. The detailed ence with international bodies and with commissioning test programmes and test reports other operating organizations and regula- for systems in safety classes 1, 2 and 3 are submit- tory bodies; ted separately to STUK for approval. STUK wit- viii. the generation of radioactive waste nesses commissioning tests and assesses the test resulting from the operation of a nuclear results before giving stepwise permits to proceed in installation is kept to the minimum prac- the commissioning. ticable for the process concerned, both in activity and in volume, and any necessary Olkiluoto unit 3 commissioning treatment and storage of spent fuel and Commissioning of the Olkiluoto unit 3 has started. waste directly related to the operation and On the turbine island, component and system com- on the same site as that of the nuclear in- missioning tests are ongoing. On the nuclear is- stallation take into consideration condi- land, commissioning is pending for the installation tioning and disposal. of operational I&C. Commissioning is divided into

69 STUK-B 164 Article 19 – Operation four actual commissioning phases followed by a waste management, radiation protection and other 30-day demonstration run before provisional take- issues related to the plant operation. over of the plant. The first commissioning phase As part of the construction inspection pro- consists of component and system testing. This is gramme inspections, STUK oversees TVO’s actions followed by overall system tests – cold and hot for ensuring that the plant is commissioned ap- functional tests – before core loading. For fuel load- propriately. ing, Operating licence and STUK’s authorisation are required. Hot functional tests with core in sub- Operational Limits and Conditions critical state and first criticality can then follow. Nuclear Energy Decree requires that the applicant After first criticality, the commissioning proceeds for an Operating Licence must provide STUK with with power tests at various power levels up to the Operational Limits and Conditions (OLCs). rated power. During power tests, transient tests The OLCs shall at least define limits for the pro- are performed. The transient tests will cover at cess parameters that affect the safety of the facility least reactor trip, turbine trip, loss of off-site power, in various operating states, provide regulations on house load operation, trip of one main circulation operating restrictions that result from component pump or main feedwater pump, as well as other failures, and set forth requirements for the test- minor operational transients. ing of components important to safety. Technical All commissioning documentation is part of and administrative requirements and restrictions Commissioning Manual which includes also or- for ensuring the safe operation of a nuclear power ganisational procedures. Vendor has prepared an plant shall be set forth in the plant’s OLCs. Guide Overall Commissioning Programme as well as YVL 1.1 requires that the minimum staff availabil- system level commissioning documentation and ity in all operational states and the limits for the TVO and STUK have approved some of these docu- releases of radioactive substances are also defined ments. Preparations for plant level commissioning in the document. are still underway, e.g. preparation of detailed The OLCs have been established for each nu- commissioning programs for the later phases of clear power plant unit and are updated based commissioning. STUK oversees the commissioning on operational experiences, tests, analyses and of safety classified systems and related result docu- plant modifications. The OLCs are subject to the mentation is provided for STUK’s review. approval of STUK prior to the commissioning of Before commissioning activities of a system can a facility. Strict observance of the OLCs is veri- be started, the system goes through a commission- fied by STUK’s continuous oversight, reporting ing inspection. This step certifies that components requirements and through a periodic inspection and system are properly installed and all activities programme. The OLCs, operating procedures and preceding commissioning have been completed. other plant documentation need to be updated as This is also part of the pressure vessel require- part of plant modification process. ments. Fortum has established the OLCs for the As the Government Decree 733/2008 states, Loviisa units 1 and 2, and STUK has reviewed one aim of the commissioning is to ensure that an and accepted them. The OLCs are continuously expedient organisation is in place for the future updated, and all the changes need to be approved operation. TVO’s personnel (e.g. future operators by STUK. The limitations and conditions of the and maintenance personnel) are participating in reactor and plant operation, the requirements for the commissioning activities in order to gain fa- periodic tests and the essential administrative in- miliarity with the plant. The documentation for structions are presented in the OLCs. operation, like operating and testing procedures, The OLCs for the Olkiluoto units 1 and 2 deter- is validated during the commissioning tests. The mine the limits of process parameters that affect Operational Limits and Conditions are being pre- the plant safety, for different operating modes, pared, and trained to TVO’s personnel. TVO is set the provisions for operating limits caused by also preparing itself for the future operation of the component inoperability and set forth the require- plant by planning refuelling outages, data systems, ments for the tests that are conducted regularly for

70 Article 19 – Operation STUK-B 164 components important to safety. Furthermore, the of applications in 2010–2012 (total 27) was a lit- OLCs include the bases for the set provisions. tle higher than the average. Most of the applica- The OLCs for the Olkiluoto unit 3 are still tions were related to modifications. In 2004 and under preparation. STUK received a preliminary 2005, the number of deviations was increased version of the OLCs for information in 2011. STUK because of work and installations related to the reviewed the general principles of the OLCs, but modernisation of Olkiluoto units 1 and 2 and the not yet the details. The OLCs for the Olkiluoto unit construction of Olkiluoto unit 3. Similarly, major 3 will define safety limits for the plant, limiting modifications were carried out during 2010 and conditions and surveillance requirements for plant 2011. In 2010–2012, there were three events at the systems, as well as administrative controls. The Olkiluoto plant in which the Operational Limits OLCs will also include bases and justification for and Conditions were violated. the conditions. Figure 18 presents the number of exemptions Procedures for operation, maintenance, and deviations from the Operational Limits and inspection and testing Conditions. The main reason for the large number Government Decree 733/2008 Section 23 requires of exemptions at the Loviisa NPP in years 2002- that the control and supervision of a nuclear power 2003 was the project to renew the radiation moni- plant shall utilise written instructions that cor- tors that required exemptions in all operational respond to the current structure and state of the states. Based on the results of the last 10 years, plant. Written orders and related instructions the Loviisa NPP applied for STUK’s approval for shall be provided for the maintenance and repair exemptions from the OLCs on the average six of components. Section 26 requires that the plant times per year. Hence, the number of applications shall have a condition monitoring and mainte- in 2010–2012 (total 18) was equal to the average. nance programme for ensuring the integrity and During the period 2010–2012, most of exemption reliable operation of systems, structures and com- applications concerned I&C renewal or overdue ponents. More detailed requirements are presented repairs of component failures. In 2010–2012, there in the Guides YVL 1.1, YVL 1.8 and YVL 1.9. The were nine events at the Loviisa plant in which the procedures for operation, maintenance, inspection Operational Limits and Conditions were violated. and testing have been established at both Finnish Seven of these events occurred in 2012, which is nuclear power plants. The procedures shall be ap- notably higher than the average two events per proved by the licensee itself, and most of them are year. Hence, Loviisa NPP has assigned an investi- required to be submitted to STUK for information. gation team to evaluate these events (see Annex 2). STUK verifies by means of inspections and con- Based on the results of the last 10 years, the tinuous oversight performed by resident inspec- Olkiluoto nuclear power plant applied for STUK’s tors that approved procedures are followed in the approval for exemptions from the OLCs on the operation of the facility. average seven times per year. Hence, the number

Number of deviations from the OLC, Loviisa NPP Number of deviations from the OLC, Olkiluoto NPP 25 12

10 20

8 15 6 10 4 5 2

0 0 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Exemptions 21 9 7 4 7 5 6 7 4 5 Exemptions 7 9 9 4 5 6 6 10 7 10 Deviations 1 2 0 2 2 2 5 0 2 7 Deviations 8 1 4 4 2 4 0 0 0 3 Figure 18. Number of exemptions and deviations from the Operational Limits and Conditions in the Loviisa and Olkiluoto NPPs.

71 STUK-B 164 Article 19 – Operation

Loviisa NPP ond annual maintenance outage and major works A structured system of procedures exists at the are carried out every fourth year. This is accom- Loviisa plant. The procedures cover work processes plished by starting from a long term investment and functions important to safety and availability. planning which converts into a long term modifica- The system of procedures is a part of the quality tion plan. system of the plant. Strict requirements have been The functioning of the systems and components set in the Quality Assurance Manual for the cover- is ensured with regular tests. The systems and age, responsibilities, updating and observance of components to be tested and the time periods of the the procedures. According to the Manual the evalu- tests are presented in the Operational Limits and ation of the system of procedures is included in the Conditions. At least the respective periodic tests annual review of the coverage and effectiveness of are required after the modification and repair- the quality assurance programme. The state of the ing works and maintenance activities requiring plant procedures is acceptable at the Loviisa plant. dismounting. The performance test programme to Procedures are maintained, evaluated and devel- be carried out after an essential modification is oped systematically and in a controlled way. The required to be approved by STUK in advance. In most important procedure types are: addition, inspections regarding to the functioning • Administrative procedures including Organisa- and condition of components are carried out when tional Manual and Administrative Rules, necessary based on operating experiences from • Operating procedures and testing procedures, other plants and on the advancement of techni- • Procedures for emergency and transient situa- cal knowledge. Other operating organisations of tions, VVER-type reactors have been essential sources of • Fuel handling procedures, operating experiences in this respect. • Radiation protection procedures, and STUK oversees monitoring and maintenance • Maintenance procedures. activities as well as repair and modification works with regular inspections and continuous oversight Loviisa plant has upgraded computer systems used performed by resident inspectors. During inspec- in managing documentation and permit-to-work tions it is aimed to make sure that the utility has system. By means of a work order system it is adequate resources, such as a competent staff, ensured that the plant operators are aware of the instructions, a spare part and material storage state and configuration of the unit. Fortum has as well as tools for the sufficiently effective im- developed, and develops further, its work order sys- plementation of the monitoring and maintenance tem based on accumulated operating experiences. activities. Special subjects are the condition moni- In addition to the work order system the operators toring programmes for the carbon steel piping and in the main control room of the units follow fail- their results. Special attention has also been paid ures, repairs and preventive maintenance of the to the reliable activities of subcontractors as well components referred to in the Operating Limits as to the technical competence of external human and Conditions. A shift supervisor gives a permit resources. Both the utility and STUK oversee com- to start a specific work when he has evaluated the panies that perform inspection activities and the work plans specified in the work order system, tak- technical competence of organisations that carry ing into account the operability requirements of out various duties. the systems and components set in the Operational Limits and Conditions. Olkiluoto NPP The maintenance activities of the Loviisa units The measures that are followed in the operation 1 and 2 cover preventive, predictive and repairing and maintenance of the Olkiluoto units 1 and 2 are maintenance as well as implementation of modifi- based on written procedures. The administrative cation works, spare part maintenance and activi- and technical procedures needed in the operation ties during outages. The scheduling of the modifi- of the Olkiluoto units 1 and 2 have been gathered cation planning for the next maintenance outage is into the Operating Manual. The Operating Manual fixed in order to get enough time for preparations. contains also necessary transient and emergency Minor modifications are concentrated to every sec- procedures for unusual conditions. The most im-

72 Article 19 – Operation STUK-B 164 portant procedures have been reviewed by STUK. STUK oversees the condition monitoring and Updating and comprehensiveness of the proce- maintenance as well as the modification and re- dures are among the inspection issues included in pair work by regularly repeated inspections. The the STUK’s periodical inspection programme. TVO inspections aim to ensure that the power company updates the procedures when necessary and checks has adequate resources such as a competent per- systematically that the procedures are up-to-date sonnel, instructions, a spare part and material in four-year-intervals. storage as well as the tools for adequately efficient The Work Request System ensures that the implementation of condition monitoring and main- operators of the plant are aware of the plant state. tenance actions. Special items are the condition TVO has developed its Work Request System and monitoring programmes of the carbon steel pipe- will continue to do so, on the basis of operational lines and their results. experience. In the main control room of the plant units, the operators follow, in addition to the Work Procedures for responding to operational Request System, the failures, repairs and pre- occurrences and accidents ventive maintenance of the components specified Government Decree 733/2008 Section 23 gives ba- in the Operational Limits and Conditions. The sic requirements for operating and emergency pro- Shift Supervisor grants the permission to begin a cedures. single work after inspecting the work plans and At both Finnish nuclear power plants, proce- taking into account the operability requirements dures for anticipated operational occurrences and for the systems and components set forth in the accidents are in use. To the extent found necessary, Operational Limits and Conditions. the procedures have been verified during operator The maintenance activities of the Olkiluoto training at the plant simulators. At both nuclear units 1 and 2 cover preventive and corrective power plants there are also advanced safety panels maintenance as well as the design and execution for monitoring critical safety functions. STUK has of modifications, spare part service, outage actions independently evaluated the appropriateness and and the related quality control. The Maintenance comprehensiveness of the procedures for antici- Department plans and implements the annual pated operational occurrences and accidents. maintenance outages together with the Operation Olkiluoto units 1 and 2 have event-oriented Department and Technical Support Department. operating procedures for events within the scope Special attention has been paid to the reliable of the design. To cope with emergency conditions work of the subcontractors and to the technical beyond design, including severe accidents, a set of competence of the external work force. The techni- symptom-based emergency operating procedures cal expertise of testing laboratories and contrac- (EOPs) is available. The focus of the severe acci- tors is controlled both by the power company and dent EOPs is on ensuring the containment integ- STUK. rity. The symptom oriented accident management The systems and the components that will be procedures (included in EOPs) apply to shutdown tested as well as the test dates are presented in states, as well, although prevention of core dam- the Operational Limits and Conditions. Periodical age is essential especially in situations with open testing that corresponds at least to the aforemen- containment. As a lesson learnt from the TEPCO tioned, is required after maintenance measures Fukushima Dai-ichi accident, the licensee will that require modifications, repairing or disassem- improve EOPs to support heat removal from spent bling. STUK’s approval is required in advance for a fuel pools by pool boiling and supplying make-up functional test programme that is conducted after water to the pools. a significant modification. Inspections that concern At the Loviisa NPP, immediate SAM measures the operability and condition of components are are carried out within the EOPs. After carrying out also conducted, if necessary, on the basis of op- immediate actions successfully, the operators con- erational experience received from elsewhere and centrate on monitoring the SAM safety functions development of technical knowledge. The most sig- with SAM procedures. The SAM procedures focus nificant sources of operational experience, in this on monitoring the leak tightness of the contain- sense, have been the Swedish BWR plants. ment barrier, and on the long-term issues. As a

73 STUK-B 164 Article 19 – Operation lesson learnt from the TEPCO Fukushima Dai-ichi internet or paper reports both in Finnish and in accident, the licensee will improve EOPs and SAM English. procedures to support heat removal from spent Figures 19 and 20 present the total number of fuel pools by pool boiling and supplying additional reported events and INES classified (≥ 1) events at water to the pools. New EOPs for shutdown states, the Finnish nuclear power plants. which cover the immediate recovery of SAM sys- tems, have been developed in 2012 and are going INES-classified events through implementation. At the Loviisa NPP, three events in 2010, two events in 2011 and twelve events in 2012 were Engineering and technical support classified on the International Nuclear Event Scale Government Decree 733/2008 Section 30 requires (INES). Five of these events were rated at level 1, that the organisation shall have access to profes- others being of level 0: sional expertise and technical knowledge required • Radioactive resin found in ventilation system in for the safe operation of the plant, the maintenance 2010 (IRS report 8088) of equipment important to safety, and the manage- • Spread of contamination in conjunction with ment of accidents. The requirements in the Guide transfers of spent fuel in 2010 YVL 1.7 also cover technical support. Competence • Deficiencies observed in the testing of radiation of the engineering and technical support is super- monitors at Loviisa unit 2 in 2012 vised by the licensee. In addition, STUK carries out • Excess fire load in the main coolant pump room inspections and audits by which also the compe- at Loviisa unit 1 in 2012 tence of the support staff is evaluated. • Incorrect settings in electrical motor protection Teollisuuden Voima Oyj is an independent or- relays at Loviisa unit 2 in 2012. ganisation and it has longstanding expertise in nuclear operations. TVO uses external expertise These incidents are described in more detail in regularly in various design and modification activi- Annex 2. ties when needed. STUK discussed the increased number of inci- Fortum has under corporate structure own unit dents with the licensee during the fall 2012. The for technical support that provides support to the licensee has started to assess the reasons behind Loviisa NPP among other projects. There are also the incidents. The assessment will be finalised dur- on-site experts at the Loviisa NPP for various engi- ing 2013 after which the corrective actions will be neering and technical support functions. implemented and followed at the Loviisa NPP. At the Olkiluoto NPP, five events in 2010, three Reporting of incidents significant to safety events in 2011 and six events in 2012 were classi- Guide YVL 1.5 provides in detail the reporting fied on the International Nuclear and Radiological requirements on incidents. The Guide provides a Event Scale (INES). Five of these events were number of examples of operational disturbances rated at level 1, others being of level 0: and events, which have to be reported to STUK. • Blowdown system failure at Olkiluoto 1 and re- It also defines requirements for the contents of pair outage at Olkiluoto unit 2 in 2010 the reports and the administrative procedures for • Use of a wrong fresh fuel delivery lot in fuel reporting, including time limits for submitting of transfer planning at Olkiluoto unit 1 in 2010 various reports. STUK publishes information con- • Defects in the internal parts of the valves of the cerning significant events (INES ≥ 1) as press re- system required for overpressure protection of leases. Information from other events is published and residual heat removal from the primary on STUK’s website. STUK describes the events circuit at Olkiluoto units 1 and 2 in 2011 also in its quarterly and yearly reports on nuclear • Deficiencies in the functioning of one outer iso- safety that are also available to the general pub- lation valve of the reactor main steam system lic through internet or paper reports in Finnish. at the Olkiluoto unit 1 in 2012 STUK’s Annual Report on nuclear safety (see • Deficiencies in the functioning of one outer iso- Reference 1) summarises events from the whole lation valve of the reactor main steam system year and is available to the general public through at the Olkiluoto unit 2 in 2012.

74 Article 19 – Operation STUK-B 164

These incidents are described in more detail in (Reporting NPP Operation to STUK), YVL 1.11 Annex 3. (Nuclear power plant operational experience feed- back), and YVL 1.9 (QA during operation of NPPs). Operational experience feedback The Guide YVL 1.11 provides detailed require- According to the Section 24 of the Government ments and administrative procedures for the sys- Decree 733/2008, nuclear power plant operational tematic evaluation of operating experiences, and experience feedback (OEF) shall be collected and for the planning and implementation of corrective safety research results monitored, and both as- actions. Operational events at other nuclear power sessed for the purpose of enhancing safety. Safety- plants and foreign operational occurrences have significant operational events shall be investigated to be systematically assessed as well, from their for the purpose of identifying the root causes as applicability and their significance for the nuclear well as defining and implementing the corrective facilities in Finland. measures. Improvements in technical safety, re- The licensees have developed the required pro- sulting from safety research, shall be taken into cedures for analysing operating experiences and account to the extent justified on the basis of the root causes for events. The licensees are using principles laid down in Section 7 a of the Nuclear WANO and IRS reports as basic material to be Energy Act. screened for external OEF and they have OEF STUK requires that all incidents at nuclear groups for screening, analysing of OE entry into facilities and activities are analyzed and reported processing and following the corrective actions. The to STUK according to the reporting criteria and licensees have also their internal audit programme the reports are assessed by STUK. Based on the and OEF is one topic in these programmes. analysis, corrective actions are planned and imple- STUK verifies by means of inspections and by mented by the operators. Regulatory requirements reviewing licensee’s event reports that the activi- are given in STUK’s Regulatory Guides YVL 1.5 ties of the licensees as regards incident evaluation

Number of operational transient reports, Loviisa NPP Number of operational transient reports, Olkiluoto NPP 7 9 8 6 7 5 6 4 5

3 4 3 2 2 1 1 0 0 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 LO1 2 6 6 2 3 3 1 3 1 3 OL1 0 3 5 3 1 3 2 2 5 1 LO2 3 3 3 3 5 3 0 0 0 4 OL2 8 3 1 1 2 2 3 0 4 2 Figure 19. Annual total number of event reports (operational transient reports) submitted by Loviisa and Olki- luoto nuclear power plants.

5 8 Olkiluoto Loviisa 7 4 6

3 5 4 2 3 2 1 1 0 0 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 INES 1 INES 1 Figure 20. Annual total number of events at INES Level 1 and above at the Finnish nuclear power plants.

75 STUK-B 164 Article 19 – Operation are effective. In STUK’s periodic inspection pro- required). Examples of such events are unexpected gramme there are two inspections related to OEF, failures of components being installed also into the namely C1 Operations and B4 Operational experi- systems or equipment of Finnish plants, or events ence feedback. When necessary, a special investiga- revealing deficiencies in procedures of the plants. tion team is appointed by STUK to evaluate a cer- Category 4 (Good practise in Finland) means that tain incident or group of incidents. The evaluation actions to prevent an event have already taken or of foreign operational occurrences and incidents is an occurrence of such an event has taken into ac- based on the reports of the IRS Reporting System count in the original design of the plant, or there (IAEA/NEA) and on the reports of other national are procedures and regulatory requirements in regulatory bodies. place (YVL Guides) preventing a similar event. For review and assessment of OE information Figure 21 shows the distribution of IRS reports abroad STUK has an internal IRS Group with a into different categories in STUK’s review and coordinator and sixteen technical experts covering assessment from 2009 to 2012. Altogether 212 all expertise areas of Nuclear Reactor Regulation IRS-reports were assessed during that period and and Nuclear Waste and Materials Regulation de- most of them (73%), 155 reports, fell into category partments. The group meets monthly and based 0 requiring no actions. 10 % (22 IRS reports) of re- on the expert assessment in STUK’s own IRS viewed reports were classified into category 2 and database the group members make together an applicability of lessons learned were checked in judgement whether there is a need for regula- the inspections of STUK’s periodic inspection pro- tory or licensee measures on the basis of lessons gramme. In the case of 14 reported events (7% of learned assigning the IRS report into categories all reviewed reports) caused actions at the Finnish with respect to actions to be taken (categories 1 to nuclear power plants. Nearly in the equal number 3), or not needed (category 0). In the case that an of cases (13 events) it was realised that similar expert to whom the report is assigned for review kind of events were prevented by technical or ad- cannot immediately say if an event requires ac- ministrative arrangements. tions at Finnish plants the report is classified into One example of foreign IRS reports which category 1 (particular issues need clarification) and caused actions at the Finnish plants in 2012 was clarifications of the applicability are initiated with ‘Reactor Pressure Vessel Flaw Indications at Doel the plant contact persons. After clarifications the 3, Belgium’ (IRS report number 8244). STUK event is reclassified. Classification into category asked clarifications by a mandatory request (let- 2 (Lessons learned need to be taken into account ter on 19th March 2012), with deadline end of May in certain activities) means that concrete actions 2013 for TVO and end of August 2013 for Fortum. are not required but the report contains informa- Number of IRS reported events classified in catego- tion which should be considered in inspections by ry 2 (Lessons learned need to be taken account in STUK. If actions are required at the Finnish nu- certain activities) is increasing: 14 events in 2012. clear power plants in operation or under construc- A fire that took place during a containment tion the report is classified into category 3 (Actions leak test carried out at the 2011 annual outage of Ringhals unit 2, as well as the obstructions in the containment spray systems of Ringhals Distribution of IRS-report’s into different categories in STUK‘s review and assessment in 2009–2012 units 2 and 4 observed during the cleaning and inspections carried out after the fire, were iden- 6% No further actions (155) 7% tified as issues relevant to the Finnish nuclear Particular issues need clarification (8) power plants eventhough not reported to IRS. 10% Lessons learned need to be taken into account in certain activities (22) STUK received the first information on the fire 4% 73% Actions required (14) in the meeting with the Swedish Radiation and Good practise in Finland (13) Nuclear Safety Authority (SSM) in mid of June 2011. STUK took the event and licensees’ actions as one item in its periodic inspection program Figure 21. Distribution of IRS-reports into different catego- inspection on “Utilization of International OE”. ries in STUK’s review and assessment in 2009–2012. The Finnish nuclear power plants have decided

76 Article 19 – Operation STUK-B 164 on several corrective actions based on this event by several means. The main sources of informa- considering containment leaktightness test pro- tion are ERFATOM (the owners group for Nordic cedures (control of fire load in the containment), BWR operators), KSU (Swedish nuclear training movable and pressure-resistant fire detectors in centre), WANO and the Swedish Forsmark NPP. the containment, inspection of pipes with x-ray Information is also coming directly from sever- or endoscope procedures, and re-evaluation of pe- al sources (IAEA and OECD/NEA, IRS), Loviisa riodic testing methods in general (scope, criteria, power plant (e.g. operating experience meetings conditions). and reports), vendors (Westinghouse Atom, Alstom Reports for the IRS System on safety-signif- Power Sweden AB), component manufacturers, the icant occurrences at the Finnish nuclear power WANO Network, BWROG (BWR Owners Group) plants are written by STUK. STUK’s international and BWR Forum (FANP). OEF group oversees the utilisation of international IRS reports are also received directly by the li- OE by licensees. censees via WBIRS and evaluated by them. Almost STUK has also participated in co-operation all plant modifications, as improvements in sys- between international organisations such as the tems, structures, and components, which have IAEA, the OECD/NEA and the EU, which ex- emerged from foreign experience originate from change information on safety issues and operating plants that are of the same type as the Finnish events. Other forums that STUK uses to obtain plants. information are WENRA, the VVER Forum and the NERS Forum as well as some bilateral agree- Management of spent fuel and ments. A special exchange of information between radioactive waste on the site Rostechnadzor and STUK on the operation of the Management of the operational low and intermedi- Kola and Leningrad nuclear power plants and of ate nuclear level wastes and the final disposal of Finnish nuclear power plants is also ongoing activ- these wastes takes place at the NPP sites. Final ity. The similar information exchange is arranged disposal facilities for low and intermediate level between SSM and STUK on the operation of the waste are in operation at Loviisa and Olkiluoto Swedish and Finnish NPPs. sites. Since the disposal facilities are operated by At the Loviisa NPP, VVER reactor operating the nuclear power plant operators, the technical experience is collected, screened and evaluated by feasibility and economic motivation to minimise a dedicated operating experience feedback group the generation of radioactive waste are evident. composed of engineers from the plant operation or- The detailed requirement for radioactive waste ganisation and from Technical Support. The main minimisation is included in the Guide YVL 8.3. It information to be handled comes from WANO calls for a limitation of waste volumes in particular (World Association of Nuclear Operators) Moscow from repair and maintenance works, and segrega- Centre which links all the VVER reactor operators. tion of wastes on the basis of activity. Clearance of Additional reports are received from the IAEA, wastes from regulatory control, prescribed in the OECD/NEA and NRC (U.S. Nuclear Regulatory Nuclear Energy Decree and in the Guide YVL 8.2, Commission). The activities of the operating expe- aims at limiting the volumes of waste to be stored rience feedback group are not limited only to VVER and disposed of. The Guide YVL 6.2 provides for reactors. The plant managers of VVER-440 reac- prevention of fuel failures, which also contributes tors have periodic meetings. The plant operation to the limitation of activity accumulation in waste problems, modernisation, back-fitting, plant life from reactor water cleanup systems. management and safety questions are handled and The Guide YVL 8.3 also requires that besides experiences are exchanged in these meetings and the short-term radiation protection objectives, also in further individual contacts. the long-term properties of waste packages with TVO has also an operating experience feedback respect to final disposal shall be taken into account group. This onsite group gives recommendations in the conditioning and storage of waste. The Guide to the line organisation that makes decisions on includes also more specific requirements for the eventual corrective actions. The industry operating conditioning and interim storage of wastes. The experience from similar reactor types is followed Guide YVL 8.1 calls for a waste type description, to

77 STUK-B 164 Article 19 – Operation be approved by STUK, for each category of reactor bedrock, one for solid low level waste and the other waste to be disposed of. In the description of waste for bituminised intermediate level waste. type, the most important characteristics of waste The original plan presented in the construc- with respect to the safety of disposal are defined. tion licence application for unit Olkiluoto 3 was to dispose all the low and intermediate level waste in Low and intermediate level waste the existing repository in Olkiluoto. However, the In 2007–2009 the policy to minimise the waste pro- waste packages of the conditioned intermediate duction at the Olkiluoto NPP has included the high level waste have different dimensions compared quality requirements for the fuel, careful planning to the waste packages from operating units in of the maintenance work and decontamination. Olkiluoto. Therefore TVO will in the operating The segregation and monitoring of the operation- licence application propose that the conditioned in- al wastes have been effective, enabling the clear- termediate level waste is first stored on-site in the ance from the regulatory control of waste below the existing waste storage facility, and later disposed clearance limits. In 2010, TVO transported mois- of in the extension of the repository. The solid low ture separator reheaters removed from Olkiluoto level waste from Olkiluoto unit 3 can be disposed of units 1 and 2 during refurbishment in 2005 and in the existing repository. 2006 to Studsvik Nuclear AB for treatment. At the end of 2012, 5965 cubic meters of low and At the Loviisa NPP, the design, construction intermediate level operating waste has accumu- and commissioning activities of the liquid waste lated at the Olkiluoto NPP and 3545 cubic meters solidification plant has continued. The plant is de- at the Loviisa NPP. About 94 % of Olkiluoto waste signed for conditioning and disposal of liquid low and 52 % of Loviisa solid waste has been disposed and intermediate level waste. Based on the results of in the on-site repositories. Low and intermediate of the commissioning tests of the plant some sys- level waste not yet disposed of is stored inside the tem modifications were designed and implemented plants. during 2011–2012. The commissioning continues in 2013 with operating personnel training activi- Decommissioning ties and updating the plant design documentation The Guide YVL 1.0 requires that provision for a and procedures. The tests of modified systems will nuclear power plant’s decommissioning shall be be finalised in 2013. The target date for the start made already during the plant’s design phase. One of the solidification plant operation is spring 2014 criterion when deciding the plant’s materials and after the regulatory commissioning inspections structural solutions shall be that volumes of de- and approval. The management of solid low and commissioned waste are to be limited. The Guide intermediate level waste has been developed by YVL 7.18 calls for selection of such construction building new facilities for the treatment, activity materials that limit the degree of activation and monitoring and interim storage of waste. New fa- spread of contamination and makes decontamina- cilities were commissioned in 2010. tion of surfaces feasible. At the Loviisa NPP site, the repository for the According to the Nuclear Energy Decree the low and intermediate level waste is located at the licence applications must include the plans for depth of 110 meters in granite bedrock. It consists decommissioning. The utilities are obliged to keep of three tunnels for solid low level waste and a the decommissioning plans up-to-date and sub- cavern for immobilised intermediate level waste. mit them to the Ministry of Employment ant the The third tunnel was built during 2010–2012 for Economy every six years, last in 2008. STUK re- the sorting and temporary storing of a low level viewed the plans and submitted its opinion to the maintenance waste. Construction was completed Ministry in 2009. A new decommissioning plan for in 2012. The commissioning of the third tunnel will Loviisa NPP was submitted in the end of 2012. be done in 2013, after the commissioning inspec- The assumption in the decommissioning plan tion made by STUK. of the Loviisa NPP is that both units will be shut The repository for the low and intermediate down after 50 years operation in 2027 and 2030. level waste at the Olkiluoto NPP site consists of The dismantling starts immediately and lasts un- two silos at the depth of 60 to 95 meters in tonalite til 2035. Olkiluoto units 1 and 2 are planned to be

78 Article 19 – Operation STUK-B 164 shut down after 60 years operation in 2038 and ing the updated safety requirements (Government 2040. The dismantling starts after 30 years delay. decision 733/2008). Extension has been included The final planning and building of disposal facili- in Olkiluoto NPP units 1 and 2 operating li- ties will start already during the safe storage pe- cence and has been handled as plant modification. riod and all together the decommissioning project STUK reviewed TVO’s application and gave ap- will last about 15 years. The reason for delayed proval for construction during first half of the 2010. dismantling is the radiation protection of the per- Extension has been planned to be ready in the end sonnel. Olkiluoto unit 3 is planned to shut down of 2013. after 60 years operation in 2070’s. The dismantling After the stress tests some safety improvements will start after the dismantling of the older units for the Olkiluoto NPP spent fuel interim storage has been completed. were identified. The possibility to feed the cooling According to STUK’s opinion expressed to the water from external source and to monitor spent Ministry of Employment and the Economy, the fuel pool water level and temperature in all cases decommissioning plans at this phase of the NPP were the most important safety features to be im- operation are reasonably comprehensive and de- plemented. The connection for feeding the cooling tailed. The decommissioning can be carried out as water from external source was already included planned, and the plans are sufficient to be used in in the design of enlargement of the Olkiluoto spent the cost estimations. fuel interim storage before Fukushima accident. At the end of 2012, the spent fuel accumulation Spent fuel at the Olkiluoto NPP was 1388 tons of uranium Spent fuel from the Loviisa NPP was transport- and at the Loviisa NPP 542 tons of uranium. ed back to Russia until 1996. Amendment of the The power companies Fortum and TVO estab- Nuclear Energy Act issued in 1994 requires that lished in 1995 the joint company Posiva to take spent fuel generated in Finland has to be treat- care of spent fuel final disposal. Research, develop- ed, stored and disposed of in Finland. Accordingly, ment and planning work for spent fuel disposal is spent fuel shipments to Russia were terminated, in progress and the disposal facility is envisaged and the necessary extension of the wet type spent to be operational in about 2022. The Decision-in- fuel storage facility was commissioned in 2001. The Principle on the spent fuel disposal facility in deep installation of the dense racks into the storage fa- crystalline bedrock was made by the Government cility started in 2007 and continues until 2018. The in 2000 and ratified by the Parliament in 2001. It capacity of the storage facility will be adequate for covers the final disposal of the spent fuel from the the total amount of the spent fuel 1100 tU allowed Olkiluoto units 1 and 2 and Loviisa units 1 and 2. in the operating licence issued in 2007. Two separate Decision-in-Principles for the dis- After the stress tests due to the TEPCO posal of the spent fuel from the Olkiluoto units 3 Fukushima Dai-ichi accident some safety improve- and 4 were made in 2002 and 2010, consequently. ments were identified for the Loviisa NPP spent The spent fuel disposal facility will be constructed fuel interim storages. The improvements concerned in the vicinity of Olkiluoto NPP site. To confirm the availability of external cooling water and con- the suitability of the site, construction of the un- nections to feed the cooling water from external derground rock characterization facility ONKALO sources. The water level and temperature monitor- was started in 2004. The excavation of ONKALO ing of the fuel pools were planned to be modified to was almost completed during 2012, but some ex- function in all conditions. Also exhaust routes for tensions will be excavated during 2013-2014. the vapour were considered to be modified. Posiva submitted a construction licence ap- At the Olkiluoto NPP, the wet type spent fuel plication for an encapsulation and final disposal interim storage facility was commissioned in 1987. facility for spent nuclear fuel to the Ministry of The current capacity about 1200 tU is adequate Employment and Economy in the end of 2012. until 2014. TVO has started the construction works The detailed technical documentation of the ap- for enlarging the Olkiluoto interim storage in plication is planned to be reviewed by STUK dur- summer 2010. The extension includes construc- ing 2013–2014 and based on the review STUK tion of three new pools and it will be done accord- will give a safety assessment for the Ministry

79 STUK-B 164 Article 19 – Operation of Employment and Economy during 2014. The ommended that companies continue negotiations construction licence application includes both the about cooperation in waste management to im- encapsulation plant and the underground disposal plement a optimal solution. Fennovoima has also facility. The capacity of the repository in the ap- started planning the environmental impact assess- plication is 9000 tU and it covers the spent nuclear ment process for a separate disposal facility. fuel from the NPP units in operation (Olkiluoto 1 A new separate favourable Government resolu- & 2, Loviisa 1 & 2), under construction (Olkiluoto tion (DiP) is anyway required for either the pos- 3) as well as a new reactor unit (Olkiluoto 4) for sible expansion of the Olkiluoto spent fuel disposal which the Decision-in-Principle was ratified by the facility for Fennovoima´s spent fuel disposal or Parliament in July 2010. alternatively for a separate spent fuel disposal Fennovoima presented in their Decision-in- facility. For both options before the DiP a recom- Principle application similar general principles as mendation on constructing the facility by the mu- Posiva for the spent nuclear fuel disposal. The posi- nicipality intended as the site, and an assessment tive Decision-in-Principle for a new reactor unit rat- by STUK on the safety of implementation are re- ified by the Parliament in 2010 included a require- quired. Furthermore, Parliament may either adopt ment for Fennovoima either to negotiate a contract or repeal the resolution. After that, a construction with the other Finnish NPP operators under waste licence and operating licence are needed for the management obligation to use the same repository, chosen option. or to start an environmental impact assessment Safety regulation for spent fuel disposal is in- process for another disposal facility for the spent cluded in the Government Decree on the safety of nuclear fuel from Hanhikivi 1 unit. Based on the disposal of nuclear waste 736/2008 and STUK’s Decision-in-Principle, Fennovoima has six years to Guides YVL 8.4 and YVL 8.5. fulfill this requirement. During 2012 the Ministry A detailed description of spent fuel and radio- of Employment and Economy formed a working active waste management and related regulation group to start the discussions on the waste man- is included in the 4th Finnish National Report as agement co-operation options. Participants of the referred to in Article 32 of the Joint Convention working group were from Ministry of Employment on the Safety of Spent Fuel Management and and Economy, Fennovoima, Posiva, Fortum and on the Safety of Radioactive Waste Management TVO. The working group produced a report which (STUK-B 138, October 2011). compared expanding the repository in Olkiluoto In conclusion, Finnish regulations and practices for Fennovoima’s spent fuel and building a second are in compliance with Article 19. disposal facility for spent nuclear fuel, and rec-

80 STUK-B 164

ANNEX 1 List of main regulations

Legislation (as of 15th April 2013) Guide YVL 1.5 Reporting nuclear facility opera- 1. Nuclear Energy Act (990/1987) tion to the Radiation and Nuclear Safety Authority, 2. Nuclear Energy Decree (161/1988) 8.9.2003 3. Act on Third Party Liability (484/1972) 4. Decree on Third Party Liability (486/1972) Guide YVL 1.6 Nuclear power plant operator com- 5. Radiation Act (592/1991) petence, 5.10.2006 6. Radiation Decree (1512/1991) 7. Government Decree on the Safety of Nuclear Guide YVL 1.7 Functions important to nuclear Power Plants (733/2008) power plant safety, and training and qualification 8. Government Decree on the Security in the Use of personnel, 28.12.1992 of Nuclear Energy (734/2008) 9. Government Decree on Emergency Response Guide YVL 1.8 Repairs, modifications and preven- Arrangements at Nuclear Power Plants tive maintenance at nuclear facilities, 2.10.1986 (735/2008) 10. Government Decree on the Safety of Disposal of Guide YVL 1.9 Quality assurance during operation Nuclear Waste (736/2008) of nuclear power plants, 13.11.1991 11. Act on the Finnish Centre for Radiation and Nuclear Safety (1069/1983) Guide YVL 1.10 Requirements for siting a nuclear 12. Decree on the Finnish Centre for Radiation and power plant, 11.7.2000 Nuclear Safety (618/1997) 13. Decree on Advisory Committee on Nuclear Safe- Guide YVL 1.11 Nuclear power plant operating ty (164/1988) experience feedback, 22.12.1994

YVL Guides Guide YVL 1.12 INES classification of events at nuclear facilities, 16.1.2002 General guides Guide YVL 1.0 Safety criteria for design of nuclear Guide YVL 1.13 Nuclear power plant outages, power plants, 12.1.1996 9.1.1995

Guide YVL 1.1 Regulatory control of safety at nu- Guide YVL 1.14 Mechanical equipment and struc- clear facilities, 10.2.2006 tures of nuclear facilities. Control of manufactur- ing, 4.10.1999 Guide YVL 1.2 Documents pertaining to safety control of nuclear facilities, 11.9.1995 Guide YVL 1.15 Mechanical components and struc- tures in nuclear installations. Construction inspec- Guide YVL 1.3 Mechanical components and struc- tion, 28.4.2008 tures of nuclear facilities. Approval of testing and inspection organizations, 17.3.2003 Guide YVL 1.16 Regulatory control of nuclear li- ability insurances, 22.3.2000 Guide YVL 1.4 Management systems for nuclear facilities, 9.1.2008

81 STUK-B 164 List of main regu lations ANNEX 1

Systems Guide YVL 3.9 Nuclear power plant pressure Guide YVL 2.0 Systems design for nuclear power equipment. Construction and welding filler materi- plants, 1.7.2002 als, 5.11.2004

Guide YVL 2.1 Nuclear power plant systems, struc- Buildings and structures tures and components and their safety classifica- Guide YVL 4.1 Concrete structures for nuclear fa- tion, 26.6.2000 cilities, 22.5.1992

Guide YVL 2.2 Transient and accident analyses for Guide YVL 4.2 Steel structures for nuclear facili- justification of technical solutions at nuclear power ties, 19.12.2001 plants, 26.8.2003 Guide YVL 4.3 Fire protection at nuclear facilities, Guide YVL 2.4 Primary and secondary circuit pres- 1.11.1999 sure control at a nuclear power plant, 24.3.2006 Other structures and components Guide YVL 2.5 The commissioning of a nuclear Guide YVL 5.1 Nuclear power plant diesel genera- power plant, 29.9.2003 tors and their auxiliary systems, 23.1.1997

Guide YVL 2.6 Seismic events and nuclear power Guide YVL 5.2 Electrical power systems and com- plants, 19.12.2001 ponents at nuclear facilities, 24.6.2004

Guide YVL 2.7 Ensuring a nuclear power plant’s Guide YVL 5.3 Nuclear facility valve units, safety functions in provision for failures, 20.5.1996 28.4.2008

Guide YVL 2.8 Probabilistic safety analysis in safe- Guide YVL 5.5 Instrumentation systems and com- ty management of nuclear power plants, 28.5.2003 ponents at nuclear facilities, 13.9.2002

Pressure equipment Guide YVL 5.6 Air-conditioning and ventilation Guide YVL 3.0 Pressure equipment of nuclear fa- systems and components of nuclear facilities, cilities, 9.4.2002 25.11.2004

Guide YVL 3.1 Nuclear facility pressure vessels, Guide YVL 5.7 Nuclear facility pump units, 1.7.2005 28.4.2008

Guide YVL 3.3 Nuclear facility piping, 26.6.2006 Guide YVL 5.8 Hoisting and transfer functions at nuclear facilities, 26.9.2008 Guide YVL 3.4 Approval of the manufacturer of nuclear pressure equipment, 14.1.2004 Nuclear materials Guide YVL 6.1 Control of nuclear fuel and other Guide YVL 3.5 Ensuring the firmness of pressure nuclear materials required in the operation of nu- vessels of a NPP, 5.4.2002 clear power plants, 19.6.1991

Guide YVL 3.7 Pressure equipment of nuclear fa- Guide YVL 6.2 Design bases and general design cilities. Commissioning inspection, 26.9.2008 criteria for nuclear fuel, 1.11.1999

Guide YVL 3.8 Nuclear power plant pressure Guide YVL 6.3 Regulatory control of nuclear fuel equipment. In-service inspection with non-destruc- and control rods, 28.5.2003 tive testing methods, 22.9.2003

82 ANNEX 1 List of main regu lations STUK-B 164

Guide YVL 6.4 Transport packages and packagings Guide YVL 7.7 Radiation monitoring in the envi- for radioactive material, 4.4.2005 ronment of a nuclear power plant, 22.3.2006

Guide YVL 6.5 Transport of nuclear material and Guide YVL 7.8 Environmental radiation safety re- nuclear waste, 4.4.2005 ports of a nuclear power plant, 22.3.2006

Guide YVL 6.7 Quality management of nuclear Guide YVL 7.9 Radiation protection of workers at fuel, 17.3.2003 nuclear facilities, 21.1.2002

Guide YVL 6.8 Storage and handling of nuclear Guide YVL 7.10 Monitoring of occupational expo- fuel, 27.10.2003 sure at nuclear facilities, 29.1.2002

Guide YVL 6.9 The national system of accounting Guide YVL 7.11 Radiation monitoring systems and for and control of nuclear material, 23.9.1999 equipment of a nuclear power plant, 13.7.2004

Guide YVL 6.10 Reports to be submitted on nu- Guide YVL 7.18 Radiation safety aspects in the clear materials, 23.9.1999 design of a nuclear power plant, 26.9.2003

Radiation protection Radioactive waste management Guide YVL 7.1 Limitation of public exposure in Guide YVL 8.1 Disposal of low and intermediate the environment of and limitation of radioactive level waste from the operation of nuclear power releases from a nuclear power plant, 22.3.2006 plants, 10.9.2003

Guide YVL 7.2 Assessment of radiation doses to Guide YVL 8.2 Clearance of nuclear waste and de- the population in the environment of a nuclear commissioned nuclear facilities, 18.2.2008 power plant, 23.1.1997 Guide YVL 8.3 Treatment and storage of low and Guide YVL 7.3 Calculation of the dispersion of intermediate level waste at a nuclear power plant, radioactive releases from a nuclear power plant, 29.6.2005 23.1.1997 Guide YVL 8.4 Long-term safety of disposal of Guide YVL 7.4 Nuclear power plant emergency spent nuclear fuel, 23.5.2001 preparedness, 9.1.2002 Guide YVL 8.5 Operational safety of a disposal fa- Guide YVL 7.5 Meteorological measurements of a cility for spent nuclear fuel, 23.12.2002. nuclear power plant, 28.5.2003 The guides are available at http://plus.edi- Guide YVL 7.6 Monitoring of discharges of radi- lex.fi/stuklex/en/lainsaadanto/luettelo/ydin- oactive substances from a nuclear power plant, voimalaitosohjeet/ (not all published in 22.3.2006 English).

83 STUK-B 164

ANNEX 2 Loviisa NPP units 1 and 2 under operation

The Loviisa plant comprises of two VVER units accident (when the emergency make-up water tank that are operated by Fortum Power and Heat Oy is empty) back into the reactor and to the spray (Fortum). The plant units were connected to the nozzles. The sumps were equipped with several electrical grid in February 8, 1977 (Loviisa 1) and hundreds of strainer units, a nitrogen flush system November 4, 1980 (Loviisa 2). The nominal ther- to blow any insulation debris off the strainers, and mal power of both of the Loviisa units is 1500 control instrumentation. The amount of debris the MW (109% as compared to the original 1375 MW). strainer system can cope with increased ten-fold. The increase of the power level was licensed in In connection with the PRISE project in 1994– 1998. The Operating Licences of the units are valid 1995 (protection from primary to secondary leaks), until the end of 2027 (unit 1) and 2030 (unit 2). the plant protection system was modified to pro- According to the conditions of the licences, two vide automatic isolation of the damaged steam periodic safety reviews are required to be carried generator at high water level (the steam and feed out by the licensee (by the end of the year 2015 and water lines are closed), and to stop the respective 2023). reactor coolant pump. The aim was to protect the steam line from water hammer. Also new measur- Most significant plant modifications at the ing equipment, based on the detection of nitro- Loviisa NPP during the plant lifetime gen-16 isotope, was installed in the steam lines in Several plant changes have been carried out dur- order to ensure the detection of any leaks from the ing Loviisa NPP plant lifetime. The most impor- primary circuit. tant projects since the plant commissioning have been modifications made for protection against Protection against fires at the Loviisa NPP fires, modifications based on the development of The possibility of fires and nuclear accident risks the PRA models, severe accident mitigation pro- caused by them were not adequately taken into ac- gramme, reactor power uprating, and contruction count initially in the functional design and the lay- of training simulator, interim storage for spent fuel out design of the Loviisa plant. Therefore, fire com- and repository for reactor operational waste. partments were not implemented so that the plant In some of the earliest modifications in 1982, safety functions could be maintained during all fire a hydrogen removal system was installed in the situations considered possible. For this reason the containment building in order to eliminate the risk significance of an active fire fighting (fire alarm of explosion during an accident when hydrogen is and extinguishing systems as well as operative fire released from the core. The system consisted of 60 fighting) is important along with structural fire glow plugs that can ignite a controlled hydrogen protection arrangements. burn. Fire safety has been improved with several In 1993, strainer area in the floor sumps of the measures at the Loviisa plant after its commis- emergency cooling system and the containment sioning. These measures have been implemented spray system was significantly enlarged by new de- in various fields of fire protection. As a result, the sign, and the sump systems were improved so as to plant safety against the effects of fires has been es- provide more reliable pumping of the water accu- sentially improved. mulated in the two sumps during a loss of coolant

84 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164

For a provision against oil fires in the turbine Severe Accident Management hall several measures have been taken. Fire insu- implementation at Loviisa NPP lators of the load-bearing steel structures of the The Loviisa severe accident programme, which turbine building have been installed. The turbine includes plant modifications and severe accident hall has been equipped with an automatic sprin- management procedures, was initiated in the end kler system and the significant parts of the tur- on 1980’s in order to meet the requirements of bines have been protected. Later on, the fire wall of STUK. For Loviisa NPP, the severe accident man- the turbine hall has been built up to protect com- agement approach focuses on ensuring the follow- ponents important to reactor decay heat removal. ing top level safety functions: Furthermore, the additional emergency feedwater • depressurisation of the primary circuit system has been built for the case that all feedwa- • absence of energetic events, i.e. hydrogen burns ter and emergency feedwater systems would be • coolability and retention of molten core in the lost in a turbine hall fire. At the Loviisa NPP the reactor vessel decay heat removal systems are in the turbine hall. • long term containment cooling That´s why a separate building for additional de- • ensuring subcriticality cay heat removal system outside turbine hall was • ensuring containment isolation. built in 2005. The new system is needed for cooling the plant to cold shutdown, if normal systems are The developed severe accident management (SAM) not operable. strategy lead to a number of hardware changes at The main transformers have been protected the plant as well as to new severe accident guide- with a sprinkler system which essentially reduces lines and procedures. the risk that a fire would spread into the sur- The primary system depressurisation is an rounding buildings, especially into the turbine interface action between the preventive and miti- hall. The risk to lose the AC-power (station black- gation parts of SAM. If the primary feed function out) during transformer fires has been reduced by is operable, the depressurisation may prevent the protecting the diesel generators against fires. The core melt (primary system cooling by feed and 110 kV net connection has been physically sepa- bleed). If not, it sets in motion the mitigation ac- rated from the 400 kV connection so that the loss tions and measures to protect the containment of both connections as a result of a transformer fire integrity and mitigate large releases. Manual de- is improbable. Several improvements against fires pressurisation capability has been designed and have been done in off-site power supply arrange- implemented through motor-operated high capac- ments and in diesel generators. The original fire ity relief valves. Depressurisation capacity will water pumps are supplied only from the off-site be sufficient for bleed & feed operation with high- electrical network. Therefore, an additional fire pressure pumps, and for reducing the primary water pump station has been constructed at the pressure before the molten corium degrades the plant. It has been equipped with diesel-driven fire reactor vessel strength. Depressurisation is to be water pumps and with a separate fire water tank. initiated from indications of superheated tempera- Fire water piping and fire extinguishing systems tures at core exit thermocouples. The depressurisa- as well as their coverage have been improved. A tion valves were installed at the same time with new addressed fire alarm system was completed in the replacement of the existing pressuriser safety 1999 at Loviisa 1 and in 2001 at Loviisa 2. Several valves in 1996. structural improvements for fire safety have been The cornerstone of the SAM strategy for Loviisa done, or are under design. is the coolability of corium inside the reactor pres- The level of the operative fire protection has sure vessel (RPV) through external cooling of been improved by establishing a plant fire fight- the vessel. Since the RPV is not penetrated, all ing crew which is permanent, constantly ready to the ex-vessel phenomena such as ex-vessel steam depart and has the proper equipment. As regards explosions, direct containment heating and core- fire protection and fire risks also plant instructions concrete interactions can be excluded. Some of the have been complemented. design features of the Loviisa plant make it most

85 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2 amenable for using the concept in-vessel retention In the 1990’s an extensive research programme of corium by external cooling of the RPV as the was carried out at Fortum to assess the reliability principle means of arresting the progress of a core and adequacy of the existing igniters system. The melt accident. Such features include the low power experiments and the related numerical calcula- density of the core, large water volumes both in the tions demonstrated that the global convective loop primary and in the secondary side, no penetrations around the containment for ensuring well mixed in the lower head of the RPV, and ice condensers conditions will be created and maintained reliably which ensure a passively flooded cavity in most provided that the ice-condenser doors will stay severe accident scenarios. On the other hand, if open. A new hydrogen management strategy for in-vessel retention was not attempted, showing Loviisa was formulated which concentrates on two resistance to energetic steam generation and cool- functions: ensuring air recirculation flow paths ability of corium in the reactor cavity could be labo- to establish a well-mixed atmosphere (opening rious for Loviisa NPP, because of the small, water of ice condenser doors) and effective recombina- filled cavity with small floor area and tight venting tion and/or controlled ignition of hydrogen. Plant paths for the steam out of the cavity. modifications included installation of autocatalytic An extensive research programme regarding hydrogen recombiners, modifications in the ignit- the thermal aspects was carried out by Fortum. ers system (igniters were removed from the upper The work included both experimental and analyti- compartment and left only in the lower compart- cal studies on heat transfer in a molten pool with ment) and a dedicated system for opening the ice- volumetric heat generation and on heat transfer condenser doors. The modifications were completed and flow behaviour at the RPV outer surface. in 2003. Based on experiments, the in-vessel retention con- The studies on prevention of long term over cept for Loviisa was finalised. STUK approved the pressurisation of the containment showed that the conceptual design in December 1995. The modifica- concept of filtered venting was not possible at the tions were completed in 2002. The most laborious Loviisa NPP because the capability of the steel one of them was the modification of the lower neu- liner containment to resist subatmospheric pres- tron and thermal shield such that it can be lowered sures is poor. An external spray system was then down in case of an accident to allow free passage designed to remove the heat from the containment of water in contact with the RPV bottom. Also a in a severe accident when other means of decay strainer facility was constructed in the reactor cav- heat removal from the containment are not oper- ity in order to screen out possible impurities from able. Due to the ice condenser containment, the the coolant flow and thereby prevent clogging of time delay from the onset of the accident to the the narrow flow paths around the RPV. start of the external spray system is long (18–36 Based on plant-specific features, the only real hours). Thus the required heat removal capacity is concern regarding potential energetic phenomena also low, only 3 MW (fraction of decay power is still is due to hydrogen combustion events. The Loviisa absorbed by thick concrete walls). The system is NPP reactors are equipped with ice-condenser con- started manually when the containment pressure tainments, which are relatively large in size (com- reaches the design pressure 1.7 bar. Autonomous parable to the volume of typical large dry contain- operation of the system independently from plant ments) but have a low design pressure of 0.17 MPa. emergency diesels is ensured with dedicated local The ultimate failure pressure has been estimated diesel generators. The active parts of the system to be well above 0.3 MPa. An intermediate deck are independent from all other containment decay divides the containment in the upper (UC) and heat removal systems. The containment external lower compartments (LC). All the nuclear steam spray system was implemented at the two units in supply system components are located in the lower 1990 and 1991. compartment and, therefore, any release of hydro- The SAM strategy implementation included gen will be directed into the lower compartment. also a new, dedicated, limited scope instrumenta- In order to reach the upper compartment, which tion and control system for the SAM systems, a is significantly larger in volume, the hydrogen and dedicated AC-power system and a separate SAM steam have to pass through the ice-condensers. control room which is common to both units. These

86 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164

were implemented mainly in year 2000 for Loviisa basis of the previous limits set for the maximum unit 1 and in 2002 for Loviisa unit 2. fuel linear power and fuel burn-up. The increase in In addition to the hardware modifications, se- the reactor thermal output was carried out by op- vere accidents guidance for the operating person- timising the power distribution in the core and the nel has been implemented. It consists of SAM pro- power of any single fuel bundle was not increased cedures for the operators and of a so-called Severe above the maximum level before power upgrading. Accident Handbook for the Technical Support In parallel with this work, more advanced options Team. The SAM procedures are entered after a related to the mixing rate of the cooling water in prolonged uncover of the reactor core indicated by the fuel subchannels and the increasing of fuel en- highly superheated core exit temperatures. The richment were investigated. The dummy elements procedures are symptom oriented and their main installed on the periphery of the core at the Loviisa objective is the protection of containment integ- units 1 and 2 were preserved to minimise irradia- rity through ensuring the top level severe accident tion embrittlement of the reactor pressure vessel. safety functions. The VVER 440 design margins in the pri- mary side are rather large and the hardware Modernisation and power uprating modifications needed there were quite limited. of Loviisa NPP in 1994–1997 Replacement of the pressuriser safety valves was The key aspects in the project for the modernisa- indicated already during the feasibility study as a tion and power uprating of Loviisa NPPs were to necessary measure because of the power upgrad- verify the plant safety, to improve production ca- ing. Most of the other substantial measures in the pacity and to give a good basis for the extension of primary side were carried out on the basis of the the plant’s lifetime to 50 years, which corresponds continuing effort to maintain and raise the safety to the additional 20 years of operation applied for level of the plant, and they were not directly in- both units of the Loviisa NPP in 2006. cluded in the power upgrading. In the first phase, before starting the project, a It was necessary to carry out more extensive feasibility study for uprating of the reactor ther- measures in the turbine plant and to the electrical mal power was carried out. The main result was components. Steam turbines were modified to a in short that no technical or licensing issues could higher steam flow rate. Because of these measures, be found which would prevent the raising of the also the efficiency and operation reliability has im- reactor thermal output up to 1500 MW from the proved. Certain modifications were carried out in original level of 1375 MW. The feasibility study the electrical generators and the main transform- gave also a good picture of the necessary plant ers to ensure reliability in continuous operation modifications. It focused on the following tasks: with the upgraded power output. the optimisation of the power level and definition The implementation of the modernisation of the new parameters of the main process, reactor project was carried out in co-operation between core and fuel studies, including RPV irradiation Loviisa NPP and Fortum Nuclear Services (for- embrittlement, safety analyses and licensing, the mer Fortum Engineering). In addition, many oth- main components and systems, and project plan- er organisations such as the Technical Research ning and risk assessment. Centre of Finland (VTT) participated in the work. The reactor power uprating from 1375 MW to The last step in the process to uprate the reac- 1500 MW was planned on the basis of optimising tor thermal power was the long-term trial run the need for major plant modifications. In the pri- to verify the main process parameters as well as mary side and the sea water cooling system, the plant operation in both steady state and transient mass flow rates were not affected, but the tempera- situations. Normal operation and in a limited way ture difference has been increased in proportion to also transient behaviour of the plant were studied the power upgrading. In the turbine side, the live in the trial tests. Studies were made by means of steam and the feedwater flow rate were increased the plant simulator and the results of transient by about 10%; the live steam pressure was not analyses were used in the planning of the trial changed. test programme. Due to the small number of plant The reactor fuel loading was considered on the modifications required for the power increase of

87 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2 the Loviisa plant, a simple trial test programme In accordance with the new procedures, nuclear supported by the simulator studies was considered power plant operators follow their own separate as appropriate and acceptable. procedures and initiate the necessary actions in The first trial run at 103% reactor power could their fields of responsibility in the event of an emer- be started in January 1997. Test runs continued gency or a transient. The shift manager co-ordinates step by step during the year, and the last transient these actions and reviews the main actions and pa- test at final reactor power 109% was completed rameters using his own procedures. The safety en- successfully in December 1997. Transient tests de- gineer in parallel with the operators independently fined in the test programme were performed with a oversees safety functions using separate procedures reactor thermal power of 105% and 109%. The test to ensure that plant behaviour is as planned. results corresponded very well with all analyses The revised procedures consist of guidelines and calculations. All the acceptance criteria for and instructions presented as flow charts. The the tests were fulfilled. Measures to improve the guidelines define strategy and give grounds for efficiency of the steam turbines continued in the operator actions during emergencies and tran- annual maintenance outages until the year 2002. sients. It serves as a basis for actual control room STUK was closely involved at every stage of procedures containing operator procedures. The the project, from the early planning of the concept guidelines are used for training purposes as well. to the evaluation of the results from the test runs. The validation and verification of the proce- STUK examined all the modification plans that dures and their background material ascertains might be expected to have an impact on plant authenticity of the procedures i.a. by comparison safety. Individual permits were granted stage by with the plant and by simulator tests. Verification stage, based on the successful implementation of authenticates i.a. correlation and functioning of previous work. the new procedures with other plant procedures. The renewal of the operating licence for the The project included training given to the control increased reactor power was carried out according room personnel of the Loviisa plant in the use of to the nuclear safety legislation. First the Ministry the new procedures. Due to the revision’s signifi- of Employment and the Economy (former Ministry cance STUK required that shift supervisors and of Trade and Industry) gave a permission to make operators working in the control room have given plant modifications and test runs with upgraded shift-specific proof of workmanship prior to the in- reactor power under the existing operating licence troduction into use of the revised procedures. and under the control of STUK. Then the assess- In December 2005, STUK authorised the in- ment of the environmental impact (EIA-procedure) troduction into service of the revised emergency of the project was carried out. STUK approved the operating procedures. Final Safety Analyses Report (FSAR), the safety-re- lated plant modifications, and the test programmes and the results. Finally the Government granted Examples of latest plant modifications the renewed operating licence in April 1998. The at the Loviisa NPP (2010–2012) licence was awarded to 1500 MW nominal reactor Improvement of safety system thermal power until the end of the year 2007. suction strainers The suction strainers of the low pressure emergen- The revision of emergency operating cy cooling system and the containment spraying procedures (2000–2005) system, which are required in accident conditions, The emergency operating procedures of Loviisa were improved by means of installing higher den- nuclear power plant were revised in the so called sity mesh elements in them. In accident conditions HOKE project, launched in 2000. The project en- caused by a pipe break, fibres coming loose from compassed the drawing up of diagnosis procedures pipe heat insulation can accumulate in the suction for transients and emergencies arising from prima- strainers. The aim is to prevent fibres from enter- ry and secondary leaks, procedures for operators ing the reactor core via the emergency cooling sys- and the safety engineer as well as action sheets for tem, because blockages caused by large amounts of onsite measures. fibres could lead to overheating of the reactor core.

88 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164

Higher density mesh elements improve the filter- auxiliary building ventilation system. The entry of ing capacity of the suction strainers, thus reducing water in the ventilation system was quickly discov- significantly the amount of fibres being carried ered because maintenance work was in progress in into the reactor core compared with the old suction the corridor along which the ventilation channel strainer structure. runs. A temporary bypass line had been made in the ventilation channel for the maintenance opera- Modernisation of the primary tion. The maintenance workers noticed that water system pressure management was seeping from the joint between the regular Modernisation of the pressuriser system at the and temporary channels and reported this to the Loviisa unit 1 was carried out in 2012. The modi- control room. fication was done because of restrictions to use the The corridor in the auxiliary building was cor- emergency spray of the pressuriser in a pressure doned off and actions were initiated in the area higher than 12 bars. At the same time, the valves of for limiting the spread of radioactivity. The venti- the pressuriser spray system were replaced and the lation system was set in filtering mode, the area spray lines coming from the high pressure emergen- was cleaned and the resin-containing water was cy core cooling system were moved to the low pres- collected. sure core cooling system. In addition, the capacity The power company performed radiation meas- of the relief train of the pressuriser was increased. urements on the ventilation lines, even further The modification also envolved I&C, electrical and away from the location of the event. Small quanti- piping changes. The same modification is planned ties of radioactive resin were found in the ventila- for implementation at the Loviisa unit 2 during the tion system in places unaffected by the migration 2014 annual maintenance outage. of resin and water that had now taken place. This led to the conclusion that radioactive resin had Construction of new off- already entered the auxiliary building ventilation site diesel power plant system on some previous occasion. The scope of Construction of a new diesel powered off-site gener- cleaning operations at the power plant was ex- ator plant was carried out in 2011-2012. The power tended and all dry resin was also collected from the of the plant is 10 MW and it can be used as a peak ventilation systems. power plant for electrical grid or as a power supply The total activity of the mildly radioactive resin for the nuclear plants. It is not safety classified, but and water entering the ventilation channel was es- it can feed power as a last resort to the safety and timated to be less than 100 MBq. The total volume non-safety classified systems of the nuclear plants. of water collected from the system was about 100 litres, and about 5 litres of wet resin and 8 litres of dry resin were also collected. The employees accu- Examples of latest incidents at mulated a collective radiation dose of 0.2 mmanSv the Loviisa NPP (2010–2012) in the course of the cleaning operation, which Radioactive resin found in means that the operation did not cause a risk to ventilation system personnel safety. Resin tanks and their overflow lines were being Because the auxiliary building ventilation sys- rinsed with pure water at the radioactive liquid tem leads the exhaust air to the vent stack, the waste solidification plant of the Loviisa power filters in the vent stack sampling lines were meas- plant in March 2010. The tanks and overflow lines ured. No radioactive particles were found in them, had minor resin residues from previous use. Resin nor were there any indications that radioactive is used, among other things, for purifying the pri- particles would have spread into the environment. mary circuit coolant water. This makes the resin The power company performed comprehensive radioactive. The level measurement of one of the measurements outside the plant buildings in order tanks was unreliable, which is why the tank was to verify that particulate resin had not escaped overfilled as a result of human error and slightly into the environment through the vent stack. radioactive water-resin mixture entered the gas The measurements concentrated on the natural exhaust line of the tank and from there to the drainage routes of melting waters and rain water.

89 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2

The measurements did not reveal any radioactive they fell to the ground when the container was be- particles. However, the power company did find ing transported. small amounts of radioactivity (Co-60) from the About 50 radioactive particles were found in samples of grit used for sanding the parking lot. the vicinity of the transfer route on the plant yard The quantity was 0.2 Bq/kg. The quantity allows when the power plant carried out measurements for the conclusion that the quantity of activity pos- on 9–10 June 2010. The measurements were con- sibly released into the environment in connection tinued on the yard area using a more accurate with the event is so small that it is insignificant for method, and 35 particles more were found around the vicinity of the plant and the people living in it. the transfer route. The particles mainly contained The event showed that liquid substances may Co-60, Mn-54, Co-57 and Co-58 nuclides. The total escape through the venting lines as a result of activity of the particles was determined and found various process measures and erroneous actions to be about 10 MBq. This is a small amount of and end up in places where they do not belong. The activity, but it should not be present outside the operation of the liquid waste solidification plant controlled area at all. has not been continued after the event. Fortum The storage and transfer route of spent nu- performed a root cause analysis of the event. clear fuel are in the controlled area of the power Fortum will investigate the process planning and plant where radioactivity is regularly monitored. instructions at the plant. The entry of liquids into Particles were only found near the transfer route the ventilation system through the venting lines and at the landfill site. The yard was cleaned of will be prevented by modifications to process tech- any radioactive particles in connection with the ra- nology. The liquid level measurement in the tanks dioactivity measurements. The event did not cause will be improved so that overfilling of the tank can any hazard to people or the environment. no longer occur. The operating instructions for the The Loviisa power plant took corrective action solidification plant will also be further specified. in order to prevent similar events. The methods On the seven-level International Nuclear Event and instructions for the transfers will be revised, Scale (INES), the event was rated at level 1. STUK and advanced radiation protection training will has also prepared an IRS report concerning the be organised for the fuel team. In addition, im- event. provements will be made to the container transfer trolley in order to prevent the spread of contamina- Spread of contamination in conjunction tion. STUK will follow the implementation of these with transfers of spent fuel actions. The event was classified at INES Level 1. Radioactive particles fell on the security-fenced yard of the Loviisa NPP from an inadequately Deficiencies in the testing cleaned transport vessel for spent nuclear fuel dur- of radiation monitors ing the period 10 May to 9 June 2010 when spent In May 2012, the Loviisa power plant informed fuel was being moved to the spent fuel interim STUK that it had found deficiencies in the test- storage from the Loviisa unit 1. The storage is lo- ing procedure of certain radiation monitors at the cated at the Loviisa unit 2. The power plant discov- Loviisa unit 2. The monitors in question are used ered the event on the evening of 9 June 2010 when to measure the radioactivity of the water let out of measuring radioactivity on the transfer route. The the secondary circuit and discharged into the sea. power plant notified STUK of the event the follow- The procedures had not been fully observed when ing morning. testing the monitors, resulting in the process con- Spent fuel is moved from the reactor hall to the trol function being left untested in some tests. In fuel storage using a purpose-built transfer contain- addition, some periodic tests had been completely er. The radioactive particles found on the transfer ignored. route were small metal particles that are present The testing requirements of radiation monitors in the fuel storage pool water in the reactor hall. are recorded in the operational limits and condi- The particles had been deposited on the surface of tions (OLC) that the power plant must comply with. the transfer container while it was in the pool, and According to the OLC, a general inspection of the because the container was not properly cleaned, monitors must be performed every two weeks, a

90 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164

functional test every month, and a calibration check the containment’s reactor coolant pump room, and every six months. Based on the investigations of where the success of first aid extinguishing is un- Fortum, there have been deficiencies in all these. certain. After the detection of the deficiencies, the ra- STUK also observed a similar event at the diation monitors and the related process control Loviisa unit 1 during the 2010 annual outage, with functions were tested in accordance with the proce- a considerably higher quantity of connectors being dures. The tests showed that the equipment func- stored. Since the 2010 event, the power plant has tioned in the normal manner. Radiation monitors improved the procedures and supervision of the have a self-diagnostics function in case of failures work. and, in addition to periodic testing, the operation Due to the repeated nature of the event, STUK of the monitors is followed in the process computer rated it as a INES category 1 event. trend displays. As the equipment functions in the normal manner, deficient testing had no immedi- Incorrect settings of protective ate importance to the safety of the plant or the relays of motors environment. At the Loviisa unit 2, thermal relays (overload pro- The preliminary classification of the event on tections) were replaced in the electrical motors of the INES scale was 0. Fortum delivered a special pumps important to safety in the annual outage in report of the event to STUK, describing the reasons autumn 2012. Approximately one month after the and corrective measures for the event. As the event completion of the annual outage, Fortum observed involved deficient quality management and unjus- that wrong settings had been entered for the re- tified ignoring of procedures, STUK rated the event lays, potentially resulting in the pumps stopping in as an anomaly belonging to INES category 1. the case of low motor supply voltage. The thermal relays are used as overload protection for the elec- Excess fire load in the containment trical motor, meant to protect the motor and to cut On STUK’s oversight rounds during the Loviisa the motor’s power supply if the motor overheats. unit 1 annual outage on 7th September 2012, ten STUK’s inspection in November revealed irreg- one-litre plastic bottles containing flammable sol- ularities in the protections of the electrical motors vent were found in a plastic bag at the shoe bound- of certain pumps important to safety. Further in- ary of a reactor pit access opening located in the vestigations by Fortum showed that incorrect set- containment’s reactor coolant pump room. The sol- tings existed in the new thermal relays installed vent was intended for the washing of the reactor into motors during the 2012 annual outage at the pit’s steel lining. According to the plant procedure, Loviisa unit 2. There were incorrect thermal relay three litres of flammable solvents may be kept in settings in a total of ten different pump motors in the open at once. Other tools meant for the clean- the emergency cooling and feed water circuits, with ing of the reactor pit, including cleaning cloths, the normal supply voltage values used instead of were also stored at the same location. undervoltage values. The incorrect relay settings The reactor coolant pump room has plenty of could have led to stopping of the pumps in under- fixed fire load, such as 5,000 kg of cable insulation. voltage situations. Washing agents do not essentially increase the fire The safety significance of the event was low, and load but together with flammable materials, they the event caused no immediate risk for the safety create the preconditions for a rapidly progressing of the plant unit or the personnel. The pumps fire that ignites cables. When PVC cables burn, the were operational in normal voltage conditions, temperature in the containment can increase to but could have stopped in undervoltage situations. 200 times the normal value, and high quantities of Undervoltages and pump malfunctions are indi- hydrogen chloride would be released. cated in the control room, which allows operators The fire safety of the Loviisa power plant’s con- to take the necessary measures following the pro- tainment is partially based on keeping fire loads as cedures. The plant unit is designed to cope with un- low as possible and minimising the ignition poten- dervoltage of the external 400/110 kV power grids tial. This is particularly important in spaces which using its four emergency diesel generators. have no fixed fire extinguishing systems, such as According to Fortum, the root cause behind the

91 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2 event was a design error in the definition of ther- Periodic safety reviews at the Loviisa NPP mal relay settings. The plant documentation used During the years 1996–1998 the overall safety re- as a basis of design work does not include under- view of the Loviisa plant was carried out by the voltage information for the pump motors in ques- licensee and independently by STUK in connection tion. The design error was not observed in connec- to the renewal of operating licences of nuclear pow- tion with the modification work or the inspection. er plant units. The safety documentation, includ- After the incorrect thermal relay settings had ing safety assessments done by the licensee, was been detected, Fortum informed the control room submitted to STUK at the end of 1996. In addition personnel of the proper procedures in undervolt- to the review of the licensing documents such as age situations. As an immediate corrective meas- Final Safety Analysis Report, STUK also made an ure, Fortum implemented the appropriate thermal independent safety assessment. The statement of relay settings. The power company will also add STUK was given to the Ministry of Employment further details to the setting and testing proce- and the Economy (former Ministry of Trade and dure, develop the plant information system and Industry) in March 1998. As regards radiation and documentation, and make additional checks to nuclear safety, the main conclusions in the state- ensure that the thermal relay settings used in the ment were that the conditions of the Finnish nu- plant unit’s electrical motors are correct. Fortum clear energy legislation are complied with. also inspected the corresponding thermal relays of The latest overall safety review of the Loviisa pump motors at the Loviisa unit 1, and no errone- plant took place in 2005–2007 in connection of ous settings were found. the relicensing of the operation of the plant. The The event was rated as category 1 on the inter- operating licence application was addressed to the national INES scale, because the erroneous relay Government and was handled by the Ministry of settings simultaneously affected the reliable un- Employment and the Economy. Fortum filed the dervoltage operation of several systems important application to the Ministry of Employment and to safety. the Economy in November 2006. Legislative and regulative requirements for the application of the Several reported incidents during 2012 operating licence are described in the Nuclear Increasing number of incidents occured at the Energy Decree (161/1988) Sections 33, 34, 36 and Loviisa NPP during 2012. Three of them were in the Guide YVL 1.1 Regulatory control of safety classified at INES Level 1 and seven of them at at nuclear facilities. INES Level 0. Several of them occurred during The Loviisa plant was reaching its original the plant outage. Incidents included deficiencies in design age in 2007–2010, but the technical and the periodic testing of equipment included in the economical lifetime of the plant is estimated to be Operational Limits and Conditions (2 incidents), at least 50 years according to the current knowl- incorrect separations and repairs (4 incidents), ad- edge of the plant ageing. Due to consistent plant ditional fire load inside the containment, indistinct improvements, the safety level of the plant has operability of the renewed valves of the pressuriser been increased as shown by the probabilistic risk system during the plant start-up, incorrect set-ups assessment (PRA). in the motor relays of the safety related pumps, Based on the application, STUK carried out a and deficiencies in the testing periods of preventive comprehensive review of the safety of the Loviisa maintenance. Several incidents included deficien- plant. The review was completed in July 2007 cies in the operations and procedures of the plant. when STUK provided the Ministry of Employment STUK discussed the increased number of inci- and the Economy with it’s statement on the safety dents with the licensee during the fall 2012. The li- of the plant. The Finnish Government granted in censee has started to assess the reasons behind the July 2007 to Fortum new licences for unit 1 until incidents. The assessment was finalised in the end the end of 2027 and for unit 2 until the end of 2030. of May 2013 after which the corrective actions will The length of the operating licences corresponds to be implemented and followed at the Loviisa NPP. the current goal for the plant’s lifetime, which is

92 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164

50 years. Two periodic safety reviews (by the end sible to be replaced by new ones (pressure vessel, of the year 2015 and 2023) are to be carried out by steam generators, etc.) are monitored most actively. the licensee as a licence condition. Several modifications have been made at the The statement of safety included also STUK’s both Loviisa plant units to reduce the risk of reac- safety assessment which provided a summary of tor vessel brittle fracture. In 1980, 36 fuel bundles the reviews, inspections and continuous oversight at the outer edge of the reactor core were replaced carried out by STUK. Based on the assessment, with by stainless steel elements (dummies) to re- STUK considered that the Loviisa Nuclear Power duce the risk of reactor vessel brittle fracture in Plant meets the set safety requirements for op- the long term. The purpose was to reduce the im- erational nuclear power plants but there are some pact of neutron radiation on the reactor pressure reservations related to the redundancy and separa- vessel thereby preventing premature embrittle- tion of components needed for performing safety ment of the pressure vessel. The reactor pressure functions (e.g. fire compartmentalisation). These vessel of Loviisa unit 1 was heat treated in 1996 to reservations are originating from the design basis restore quality of one of the mostly affected weld- laid down during the 1970s. However, substan- ings. tial modernisations have been carried out at the Fortum stated during the last operating licence Loviisa NPP since its commissioning to improve renewal process that the brittle fracture risk can safety. Risk factors have been systematically iden- be managed until the end of the 50 years plant tified and eliminated using operating experience, lifetime. The primary circuits of both Loviisa plant research and development and probabilistic risk units are still in good condition. The validity of the analysis. Examples of such plant modifications operating licence of the reactor pressure vessel include the development of fire detection and fire of the Loviisa unit 2 was extended in 2010 until extinguishing systems, as well as operative fire the end of 2030, i.e, to the end of the plant unit’s protection in parallel with structural fire protec- current operating licence. Similarly, STUK as- tion. The most recent risk reducing modifications sessed the renewal of the reactor pressure vessel include also improvements to the plant residual operating licence for the Loviisa unit 1 in 2012 and heat removal and emergency cooling systems and the validity of the operating licence of the reactor ensuring the cooling of reactor coolant pump seals. pressure vessel of the Loviisa unit 1 was extended Fortum has also many ongoing projects for enhanc- until the end of the plant unit’s current operating ing safety and reducing the accident risk. They licence. In the future, the safety of the reactor will include e.g., improvements aiming at prevention be assessed in connection with the plant’s periodic reactor coolant pump seal leaks with regard to fire safety reviews. and flood conditions, precautions against oil ac- cidents in the Gulf of Finland, and improvements Planned and ongoing activities to aiming at reducing the risk arising from heavy improve safety at the Loviisa NPP load lifting with the structural reliability of the po- In Finland, the continuous safety assessment and lar crane and developing the procedures relating to enhancement approach is presented in the nu- lifting. This is in line with the principle of continu- clear legislation. Actions for safety enhancement ous improvement of safety provided in section 7 a are to be taken whenever they can be regarded of the Nuclear Energy Act. as justified, considering operating experience, the As a summary of the review of the issues and results of safety research and the advancement documentation pertaining to the periodic safety of science and technology. The implementation of review and the continuous oversight results, STUK safety improvements has been a continuing pro- noted that the prerequisites for safe operation of cess at the Loviisa nuclear power plants since its Loviisa NPP have been met. commissioning and there exists no urgent need to upgrade the safety of this plant in the context of Reactor pressure vessel relicensing the Convention. Plant lifetime management includes credible pro- For continued safe operation, plant improve- cedures for following the plant ageing. The condi- ment projects are still necessary. The largest ongo- tions of components which are practically impos- ing investment is the complete renewal of the plant

93 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2

I&C system. Also some improvement measures of extreme value distribution fitting, the annual will be done based on the lessons learnt from the probability of exceeding the level +3 m is about TEPCO Fukushima Dai-ichi accident. 4·10-7. The refueling shutdowns are scheduled for summer and early autumn when the seawater Safety assessments and improvements level variations are small. The design basis of the based on the lessons learnt from Loviisa NPP is considered sufficient in the short TEPCO Fukushima Dai-ichi accident term. Although the estimated annual probability Based on the results of assessments conducted af- of exceeding the design value is very small, the ter the TEPCO Fukushima Dai-ichi accident on 11 consequences of flooding of the basement of the March 2011, it is concluded that no such hazards Loviisa NPP would be severe, as all cooling systems or deficiencies have been found as would require might be lost. Therefore, to ensure safe operation immediate actions at the Loviisa NPP. However, in the long term, the possibilities for decreasing the areas where safety can be further enhanced the risk of seawater flooding have to be examined. have been identified and there are plans on how Loviisa NPP has improved in 2012 flood protec- to address these areas. Main changes are aimed at tion during certain annual shutdown states with decreasing the dependency on plant’s normal elec- open hatches in the condenser cooling seawater tricity supply and distribution systems as well as system; the design water level was increased from on the sea water cooled systems for residual heat +2.1 m to +2.45 m and further increase to +2.95 m removal from the reactor, containment and spent is considered. fuel pools. The licensee has also been required to The licensee has been required to submit plans submit plans to improve protection against exter- to improve protection against external flooding by nal flooding by the end of 2013. the end of 2013. The licensee is examining site area protection with levees and the protected volume Natural hazards approach and also their combination to improve of According to the PRA results, the risk caused to the flooding resistance of the Loviisa plant. The li- the operating units by external events is a rela- censee will make decisions based on updated flood- tively small fraction of the total risk. However, ing hazard estimates contracted from the Finnish there are areas where possibilities for further risk Meteorological Institute. reduction exist, for example improving the protec- tion against high seawater. Design issues Safety margins were assessed by the licensee At the Loviisa NPP, the systems needed for residu- and reviewed by STUK. Based on the results, al heat removal from the reactor, containment and STUK required further clarifications on the follow- fuel pools require external power and the ultimate ing main points: heat sink is the sea. A reliable supply of electrical • seismic resistance of spent fuel pools including power to the systems providing for basic safety situations with water temperature exceeding functions at the Loviisa NPP is ensured by the the design bases; Defence-in-Depth concept. As a result of multiple • seismic resistance of fire fighting systems; and and diversified electrical power sources at differ- • plans for improving flooding margin for the ent levels, the probability of loss of all electrical Loviisa plant by end of 2013. supply systems is considered very low. However, as a result of the studies made after the TEPCO Seawater level variations in the are Fukushima Dai-ichi accident, further changes are moderate. Due to geological conditions and the expected to be implemented. Main changes are shallow water strong tsunami type phenomena aimed at decreasing the dependency on plant’s nor- are not considered possible in the Baltic Sea. At mal electricity supply and distribution systems as the Loviisa NPP, the observed maximum seawater well as on the sea water cooled systems for residu- level is +1.77 m above the mean sea level (N60 al heat removal from the reactor, containment and reference system). The design basis of the Loviisa spent fuel pools. NPP is about +3 m during power operation and At the Loviisa NPP, the availability of an alter- about +2.1 m during refueling shutdown. Based nate heat sink depends on the plant state and feed

94 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164 water availability. If primary circuit can be pres- ing of the fuel in fuel storages. In spite that there surised (i.e. reactor vessel head is in place), atmos- are fixed severe accident management systems in- phere can be used as an alternate heat sink as long stalled at Loviisa operating units, STUK required as there is enough water available for dumping the licensee to investigate needs and possibilities steam into atmosphere from the secondary circuit. to use mobile power supply and mobile pumps There is a separated diesel driven auxiliary emer- in accidents. Loviisa NPP has studied the possi- gency feed water system with two pumps which bilities to utilise mobile power supply and mobile feeds water to the steam generators in case of loss pumps to support safety functions. of AC power. It is also possible to transfer heat to At the Loviisa NPP, the current AC power sup- spent fuel cooling system and hence to intermedi- ply systems include connections to 400 kV and ate cooling system, giving time for restoring ulti- 110 kV power grids, main generator (house load mate heat sink. operation), four emergency diesel generators per The licensee at the Loviisa NPP considers a unit, a diverse diesel power plant and a dedicated plant modification to ensure the long-term decay connection to a nearby hydropower plant, two SAM heat removal in case of loss of seawater by imple- diesel generators, and the possibility to supply menting an alternative ultimate heat sink. The electricity from the neighbouring NPP unit. No modification consists of two air-cooled cooling units modifications are planned to the current design per plant unit powered by an air-cooled diesel-gen- concerning AC power supply. erator. The other cooling unit would remove decay At the Loviisa NPP, there is enough diesel fuel heat from the reactor and the other one ensures in the emergency diesel generator (EDG) tanks for the decay heat removal from in-containment spent at least 72 h of operation, and with realistic loads fuel pool and from the spent fuel storage pools. in case of an accident, the duration is evaluated The cooling unit is connected to the intermediate twice as long. Currently the emergency diesel gen- cooling circuit, and it backs up the seawater cooled erators (EDGs) at the Loviisa NPPs use conven- heat exchangers. The cooling units for the reactors tional diesel fuel, which is available only in limited are dimensioned to be able to remove the deacy scope. An investigation of replacing conventional heat after 72 h, and until then the heat removal diesel with widely available biodiesel is being can be carried out by steam dumping into the performed by the licensee and the diesel engine atmosphere from the steam generator secondary manufacturer. In 2012, the licensee of the Loviisa side. The modifications in consideration would NPP purchased a container to transfer diesel fuel create a possibility to closed-loop operation also in at the site. The purpose of this container is to make case of loss of ultimate heat sink. The conceptual fuel transfer between the tanks on-site easier and design plan is ready and the cooling towers are faster. In addition, the licensee has started an in- planned to be realised in 2014. vestigation to build a new fuel storage tank, from In addition, the licensee has evaluated meas- which it is possible to deliver fuel to the diesel gen- ures needed to secure the availability of the aux- erators’ day tanks. iliary emergency feedwater system in the case of At the Loviisa NPP, some DC batteries deple- loss of electrical power, water supply for the diesel tion times are considered to be rather short. The driven auxiliary emergency feed water pumps, and duration of DC power supply is considered to be electricity supply for instrumentation needed in enhanced. Especially the reactor coolant pump seal accidents. The modifications will be realised during water system functionality must be ensured. The 2012 and 2013, with the exception of improving the licensee will submit a plan to STUK. There is also instrumentation by 2015. an ongoing automation renewal project in which The experiences from the Fukushima Dai-ichi the depletion time of the batteries will be length- accident will be taken into consideration in the ened substantially. It is possible to charge the ongoing renewal of the Finnish Regulatory Guides batteries using the AC power sources. The licensee (YVL Guides). For example there will be a new re- will install two new separate underground cables quirement for arrangements that enable the decay from the new diesel power plant to the 6.3 kV die- heat removal from the reactor out of the contain- sel busbar in 2012–2013, which will furthermore ment and arrangements to ensure sufficient cool- ensure and enhance battery charging possibilities.

95 STUK-B 164 Loviisa NPP u nits 1 and 2 u nder o peration ANNEX 2

Regarding spent fuel pools, the approach in ment and mitigation of severe accidents have al- Finland is to “practically eliminate” the possibil- ready been implemented at Loviisa operating units ity of fuel damage. The licensee have evaluated and the corresponding procedures are in place, no alternative means of decay heat removal from fuel further measures for this purpose are foreseen at storage pools in case of loss of existing systems, the moment. However, the soundness and adequa- and to supply coolant to fuel storage pools (includ- cy of the accident management schemes is being ing potential need for new instrumentation). The constantly assessed against the latest knowledge plant modifications will require further analy- and experience obtained from different interna- sis before starting the detailed design work. The tional sources. more detailed analysis will be performed in 2013. Loviisa NPP is investigating possibilities to Furthermore, the licensee will improve EOPs and implement additional injection points for mobile SAM Guidelines to support heat removal from pumps to provide more flexibility to the water sup- spent fuel pools by pool boiling and supplying ad- ply of the containment external spray. These con- ditional water to the pools. Licensee is also study- nections could provide capability to inject enough ing the seismic resistance of the fuels pools as well water for both units with one pump. The different as the influence of pool water boiling to the pool possibilities will be analysed in more detail in structures. 2013. Currently, the containment external spray- ing for heat removal from the containment can Severe accident management be carried out by fire trucks, individually for both A comprehensive severe accident management of the units, in case of failure of the fixed pumps. (SAM) strategy has been developed and imple- Investment decision for mobile power supply and mented at Loviisa 1&2 plant units during 1990’s mobile pumps will be made after related assess- after the accidents in TMI and Chernobyl (see ments on the need and purpose of mobile devices above). These strategies are based on ensuring the have been completed. Implementation is planned containment integrity which is required in the ex- to be made in 2013. isting national regulations. STUK has reviewed At the Loviisa NPP, immediate SAM measures these strategies and has made inspections in all are carried out within the Emergency Operation stages of implementation. Procedures (EOP). After carrying out immediate As a result of the studies made after the TEPCO actions successfully, the operators concentrate on Fukushima Dai-ichi accident, no major changes at monitoring the SAM safety functions with SAM the plants are considered necessary. However, the procedures. The SAM procedures focus on monitor- licensee is expected to consider spent fuel pools in ing the leak tightness of the containment barrier, the SAM procedures as well as any implications and on the long-term issues. At the Loviisa NPP, on them possibly arising from simultaneous multi licensee will improve EOPs and SAM procedures unit accidents. In addition, there are many actions to support heat removal from spent fuel pools by related to the update of the emergency plans. pool boiling and supplying additional water to the At the Loviisa NPP, the design basis for all pools. New EOPs for shutdown states, which cover SAM safety functions is that the actions can be the immediate recovery of SAM systems, have been done, when the other supplies have been lost, with developed in 2012 and are going through imple- dedicated independent SAM electrical systems and mentation. dedicated independent SAM I&C from SAM con- trol room or main control room. The SAM strate- I&C renewal project at Loviisa NPP gies and their implementation at the Loviisa NPP I&C systems of the Loviisa nuclear power plant follow the requirements set in the Government units are being renewed stepwise in a project that Decree 733/2008 and the YVL Guides. The ap- will continue for several years. Some modifications proach and the plant modifications have been will also be made to the functions of the plant sys- approved by STUK. Since the systems for manage- tems. Furthermore, a new emergency control room

96 ANNEX 2 Loviisa NPP u nits 1 and 2 u nder o peration STUK-B 164 will be provided for each unit to replace the emer- Construction and commissioning of a gency control panels currently located mutually liquid waste solidification facility in the main control rooms of the other unit. I&C A solidification facility for liquid radioactive waste renewal will be implemented in several project has been constructed on the Loviisa plant site. phases so that each phase will be adopted during The solidification facility processes the evapora- maintenance outages. tion residues generated at the power plant and Preliminary planning of the renewal project the radioactive ion exchange resins from the pu- started several years ago and in the beginning of rification filters. The power company initiated the 2005 the licensee signed the delivery contract with commissioning phase of the solidification facility the consortium of and Siemens. New implementation project during 2006 by carrying buildings at the plant site have been constructed out system and plant level tests using inactive and will accommodate the main equipment of the substances. Plant level tests continued in 2008 us- safety and operational I&C. The first phase of the ing radioactive evaporation residues and in 2009 project included e.g. the renewal of the reactor with radioactive ion exchange resins. Based on preventive protection I&C and was implemented the results of the commissioning tests of the plant in the outage 2008 at Loviisa unit 1 and at Loviisa some system modifications were designed and im- unit 2 in the outage 2009. The second phase of plemented during 2011–2012. The commissioning the project including the renewal of the reactor continues in 2013 with operating personnel train- protection system is planned to be implemented at ing activities and updating the plant design docu- the Loviisa unit 1 during the outage 2015. Safety mentation and procedures. The tests of modified classified parts of the project are intended to be systems will be finalised in 2013. The target date completed in 2017. for the start of the solidification plant operation is spring 2014 after the regulatory commissioning inspections and approval.

97 STUK-B 164

ANNEX 3 Olkiluoto NPP units 1 and 2 under operation

The Olkiluoto plant comprises of two BWR units arising from a severe accident and to find means that are operated by Teollisuuden Voima Oyj for controlling the loads on the containment. The (TVO). The plant units were connected to the elec- main provisions for severe accident management trical network in September 2, 1978 (Olkiluoto 1) were installed at the Olkiluoto units 1 and 2 dur- and February 18, 1980 (Olkiluoto 2). The nominal ing the SAM project which was finished in 1989. thermal power of both Olkiluoto units is 2500 MW, The measures implemented were which was licensed in 1998. The new power level • containment overpressure protection is 115.7% as compared to the earlier nominal pow- • containment filtered venting er 2160 MW licensed in 1983. The original power • lower drywell flooding from wetwell level of both units was 2000 MW. The Operating • containment penetration shielding in lower dry- Licences of the units are valid until the end of well 2018. According to the conditions of the licences, • containment water filling from external source the licensee carried out a periodic safety review • containment instrumentation for severe acci- and submitted it to the regulator in the end of dent control 2008. • Emergency Operating Procedures for severe accidents. Most significant plant modifications at the Olkiluoto NPP during the plant lifetime The means for managing severe accidents had to Several plant changes have been carried out dur- be adjusted to the existing design, and so an opti- ing Olkiluoto NPP plant lifetime. The most impor- mal implementation of all chosen solutions was not tant projects since the plant commissioning have possible. Subsequent development of the accident been two reactor upratings, severe accident miti- management procedures and additional minor gation programme, modifications based on the de- plant modifications at Olkiluoto plant have taken veloment of the PRA models, contruction of train- place during the years after that when new aspects ing simulator, interim storage for spent fuel and on the issue have emerged. repository for operational waste, and investigation To secure depressurisation of the reactor pri- programme for disposal of spent fuel. The first mary system in severe accident situations and to power uprating project was carried out in 1983– prevent a new pressurisation of the reactor, two 1984. Thermal power was uprated from 2000 MW valves of the relief system were modified. It is now to 2160 MW (8%). The plant modifications included possible to keep the valves open with the help of for example a new relief valve that was installed in nitrogen supply or water supply from outside the the reactor primary system, changes in the reactor containment. protection system, and increase of cooling capacity One of the most significant deficiencies at the of some heat exchangers. Olkiluoto plant containments, from the standpoint of controlling severe accidents, has been the small Severe Accident Management size of the containment, which may cause the implementation at the Olkiluoto NPP containment to pressurise due to the hydrogen Several new research programmes were launched and steam generation during an accident (com- in the beginning of 1980’s, whose objective was both mon feature for BWRs). Another deficiency is the to clarify the character and magnitude of loads location of the reactor pressure vessel inside the

98 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 containment, which is such that the core melt filtered venting system, chemicals have been added erupting from the pressure vessel may expose the to the water in the scrubber tank of the system. structures and penetrations that ensure the tight- To minimise the formation of organic iodine, it is ness of the containment, to pressure loads and also possible to control the pH of the containment thermal stresses. To eliminate these deficiencies, water volume by a specific system. The function the containment was e.g. provided with a filtered of the system is based on addition of NaOH to the venting system. Gases that pressurise the contain- fire fighting water reservoir which is used for fill- ment can be removed through a filter designed for ing of the containment in post-accident conditions. the purpose, if the pressure inside the contain- The lower drywell will be flooded from the wetwell ment threatens to increase too much. The part of prior to the NaOH supply and the lower drywell the containment underneath the reactor pressure water pool pH will be kept above 7. vessel can be flooded with water in order to protect the containment bottom and penetrations from Protection against fires at the Olkiluoto NPP the thermal effect of core melt. Some penetrations The possibility of fires and the risks of nuclear of the containment have been protected from the power plant accidents arising from fires have been direct effect of core melt also by structural means. taken into account in the functional and layout To ensure the cooling of reactor debris, the plant design of the existing Olkiluoto plant. Fire safety units are also provided with a water filling system, has been improved in different areas of the fire by the means of which the water level inside the protection at the existing Olkiluoto plant after containment can be raised all the way to the same commissioning. Although the loss of external elec- level with the upper edge of the reactor core. trical supply has been taken into account in the The cooling of reactor core melt and the protec- plant design, both units were provided with e.g. tion of containment penetrations requires that the second start-up transformer, based on the experi- lower dry well of the containment is flooded at such ence gained from the fire of the electric supply unit an early stage of the accident that if the pressure in 1991, to improve the independency of plant’s vessel melts through, the erupting core melt falls external grid connections. Furthermore, the main into a deep water pool. When the core melt falls transformers, in-house transformers and start-up into the water a so-called steam explosion, which transformers are protected with a sprinkler ex- causes a strong and quickly propagating pressure tinguishing system, which reduces essentially the wave in the water pool, may occur. A lot of research risks arising from transformer fires. The use of has been done on steam explosions. The results halon is forbidden in Finland since the year 1999 show that the core melt discharged through the with the exception of some special items. Due to pressure vessel cools down as it travels through this the halon extinguishing systems at the exist- the water pool and cannot create a steam explo- ing Olkiluoto plant were replaced with other extin- sion. However, the structures of the lower equip- guishing systems by the year 2000. Fire risks have ment hatch have been enforced to decrease the been assessed in a probabilistic risk assessment risk for loss of containment integrity due to loads that concentrates on fire issues. Based on this the caused by limited steam explosions. fire protection of cables, that are crucial to safety, Research results have demonstrated that in have been improved by renewing fire detectors and unfavourable conditions iodine may form organic improving fire extinguishing systems in cable tun- compounds that are not easily absorbed in the nels. On the basis of the probabilistic risk assess- containment or in the filter. Such conditions may ment these improvements reduce the risks arising occur at the Olkiluoto plant, if the water inside the from fires considerably. containment is acidified due to chemicals released during the accident. Organic iodine may also be Modernisation and power uprating generated in the primary circuit, if iodine reacts of Olkiluoto NPP in 1994–1998 with the hydrocarbons that are released, when The main goals of the modernisation project at the boron carbide contained in the control rods be- the Olkiluoto NPP were the reviewing of safety comes oxidised during the core damage. To improve features and enhancing safety, when feasible, im- the possibilities for retaining organic iodine in the proving the production related performance, find-

99 STUK-B 164 Olkiluoto NPP u nits 1 and 2 u nder op eration ANNEX 3 ing factors limiting the plant lifetime and elimi- from 2160 MW to 2500 MW (15.7%). The most im- nating them, when feasible, and enhancing the portant changes were made in fuel technology. The expertise of the own staff and improving productiv- operation was changed from with 8×8 bundles to ity. In order to achieve the safety goal, the exist- 10×10 bundles. The new bundles have 40 percent ing plant design was reviewed and compared by lower average linear heat rating than the old ones. the TVO to the present and foreseeable safety re- Some additional design changes implemented due quirements. Compliance with the European Utility to the uprating were the increasing of inertia of the Requirements (EUR) was also reviewed. The feasi- main circulation pumps electrically, steam separa- bility of fulfilling new requirements set for the new tors replacement, high-pressure turbine and feed nuclear power plants was considered case by case. water system modifications, decay heat removal The living PRA model of the plant was utilised in system capacity increasement, and generator and this context. main transformers replacements. The low pressure The most important safety related modifica- turbines were also replaced and in that way about tions included in the modernisation programme 30 MW additional production capacity in each unit are listed below: was achieved. • Reactor pressure relief system was diversified The modernisation programme of the Olkiluoto by installing two additional relief valves. plant units 1 and 2 was started in 1994 and com- • ATWS behaviour was improved by modifying pleted in 1998. The installations were performed some trip signals and making boron injection during the refuelling outages of the years 1996– automatic and more effective. 1998. Some later installations were realised during • Additional severe accident mitigation measures outages in 1999. In spite of large modifications the were implemented. refuelling outage times were reasonable, between • Earthquake resistance of the plant was checked 15 and 20 days. The test programme was quite the and related modifications were made. same as in the case of a new plant. • Partial scram function was strengthened. Test operations were conducted in stages at • Generator breaker was replaced with a new different power levels under STUK’s supervision one, which is able to break also short circuit and within the frames permitted by STUK. Before current. uprating the reactor power to a higher power level • Protection against frazil ice at the seawater in- STUK conducted a safety review concerning the take was improved. test operation for the power level in question and • Protection against snowstorms at the air intake asked the Nuclear Safety Advisory Committee for of the emergency diesels was improved. a statement concerning the review before granting the test operating licence. Modification of the safety features in connection Test operation programmes that included the with the modernisation programme as a whole re- entire plant units and were drawn up by TVO, were duced the severe core damage frequency estimate based on the original commissioning programmes by a factor of three. that were run through during the start-up phase The radiation exposure of the population was and that were modified taking into account the test reduced in accordance with the ALARA principle. requirements caused by the modernised systems. Liquid releases were reduced by a factor of ten For the long-term test operation of the plant units by improving the liquid waste handling systems. the thermal power of reactor units were uprated Also occupational doses were reduced. In practice, step by step from the nominal power of 2160 MW this meant minimising the cobalt content in the to 2500 MW. primary circuit. Renewal of steam dryers reduced The most significant plant transient tests of the occupational doses remarkably, because the the test operation were the load rejection test, moisture of the steam was reduced. turbine trip test and the by-pass test of the high- The development of the BWR technology, mar- pressure preheaters. STUK considered it necessary gins revealed by operational experience, and plant to continue the test operation at the 2500 MW modifications due to other reasons made also pow- power level for about two months before issuing er uprating possible. Thermal power was uprated a statement in favour of continuing the operation

100 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 of the plant units at the 2500 MW power level. ble technology was the obsolescence the old system. Licensing steps related to the modernisation In addition, the modifications made in the turbine programme included an uprated Safety Analysis plant process in 2005, and in 2006, required some Report (PSAR, for example) and an uprated additional modifications to the automation system. Probabilistic Safety Assessment (level 1 PSA), The new system improves information manage- which were reviewed and approved by STUK. ment and control of the turbine plant as well as Design modifications and test runs were accepted facilitates component maintenance. Another sys- by STUK before implementation. The Final Safety tem renewal objective is increased reliability and Analysis Report (FSAR) and the related Topical reduced susceptibility to malfunctions by added Reports were rewritten. It meant also that al- redundancy. most all transient and accident analyses were The new automation system is implemented redone taking into account the uprated power by programmable technology. This allows an in- level and modified plant design. The FSAR and creased number of process status measurements Topical Reports were submitted to STUK at the and versatile information handling possibilities. As end of 1996. An operating licence renewal applica- regards turbine automation, it facilitates for tur- tion, covering design modifications and the power bine operators improved information management, uprating, was submitted to the Government at the process control at operating work stations, trend end of 1996. The licence was granted in 1998. The monitoring and setting of safety limits. Safety limit power uprating was reviewed also according to the settings enable turbine operator reaction to even Environmental Impact Legislation. minor process changes. The control desk for the Modernisation and power uprating project con- turbine side in the control room was replaced with tained several safety, ageing and efficiency rem- a safety function control desk and a turbine sys- edies. Mostly influences of modifications have been tems control and monitoring board with operator’s positive. A negative finding has been a slight work stations. The control room was also fitted increase of steam moisture. To improve this in with a screen display. In addition, the process com- both units steam dryers were replaced in out- puter system capacity had to be upgraded in con- ages 2005–2007. Another slightly negative finding nection with the control system renewal to handle was increase of condensate clean up temperature, the large volume of data yielded by the turbine au- which decreased the life cycle of clean up resins. tomation. The automation interface was introduced To avoid this problem the location of condensate at the Olkiluoto units 1 and 2 training simulator in clean up system was changed in the process. In this September 2004, which made possible the training context even the first LP-preheaters were replaced of operating personnel in its use. and modernised. The modernisation of turbine plant was contin- Examples of latest plant modifications ued with replacement of steam reheater moisture at the Olkiluoto NPP (2010–2012) separators (MSR). They were replaced with mod- During the years 2010 and 2011, the Olkiluoto nu- ern two stage MSR’s. This replacement required clear power plant implemented large modifications modernisation of HP-turbine as well. These re- improving plant safety and the availability of the placements were performed in outages 2005 and plant. During the maintenance outage 2010 at the 2006. In the same outages the I&C system of the Olkiluoto unit 1, the implementation of the PELE turbine plant process was be replaced with a mod- project (Plant Efficiency improvement Lifetime ern digital one. Extension) started with the replacement of the in- ner isolation valves of the main steam system, up- Turbine plant process automation grade of the low pressure turbines, modernisation system renewal (2004–2006) of the main service water pumps and the upgrade A new computerised turbine plant automation sys- of the generator cooling water system. The project tem was installed in the Olkiluoto unit 2 in 2005 continued in the following years with the upgrade annual maintenance outage (equivalent modifica- of the generator and the low voltage switchgear. tion was performed at Olkiluoto unit 1 in 2006). At the Olkiluoto unit 2, a corresponding upgrade One reason to switch from analogue to programma- project started during the 2011 outage.

101 STUK-B 164 Olkiluoto NPP u nits 1 and 2 u nder op eration ANNEX 3

Replacement of the inner isolation Upgrade of the plant radiation valves of the main steam pipes measurement systems The main steam line isolation valves inside the In a radiation measurement equipment up- containment were replaced at the Olkiluoto unit grade project, practically all stationary radiation 1 during annual maintenance in 2010 and at the measurement equipment will be replaced at the Olkiluoto unit 2 during annual maintenance 2011. Olkiluoto units 1 and 2. The first new devices were The function of the valves is to isolate the reactor installed and operational in 2008. Apart from the pressure vessel and prevent the loss of reactor existing measurements, some completely new coolant and releases of radioactivity outside the measurements will be installed in the project. The containment. The valves also function as a backup purpose of the test operation is to compare the for the isolation valves outside the containment. measurement results of the new devices with the One reason for the valve replacement was the measurement results of the old devices. The aim tendency of the old valves to close as the steam has been to place the new devices in more repre- flow increases. In a situation where one valve sentative places according to operating experience closes, the steam flow through the other valves gained. Another aim has been to find alarm limit increases and this can make them close, too. The set values that would be optimal in terms of ra- near simultaneous closing of all the steam line diation safety and plant process monitoring. The isolation valves causes a greater pressure rise and radiation measurement system upgrade will still load on the reactor pressure vessel than the closing continue in the next few years. of one valve only. The new valves are wedge gate valves, which Low-voltage switchgear replacement project operate on a medium (steam) and on pressurisa- TVO has initiated a project (the SIMO project) for tion principle. This type of valve does not have the replacing the switchgears of the low-voltage distri- risk of self closing caused by a steam flow increase. bution systems at the Olkiluoto units 1 and 2. The The factory acceptance test of the valves revealed primary reason for replacing the switchgears is the that the partial stroke function intended for peri- increase in maintenance costs due to the ageing of odic testing did not operate as planned, and the original equipment, as well as the need to modern- partial stroke related parts were removed from ise the switchgear to correspond to the current re- the valves before their installation at the power quirements regarding plant and personnel safety. station. Provisions have been made for reinstalling The replacement mainly concerns the switchgears the partial stroke function, and it will be possible and associated transformers of electrical systems when the manufacturer has demonstrated through important to safety. TVO has already replaced the extensive factory acceptance tests that partial medium-voltage switchgear (6.6 kV) in 2005 and stroke functions as planned. 2006. The voltages in the low-voltage networks of STUK reviewed and assessed the valve de- the units vary from 24 V DC to 660 V AC. The sign documentation before manufacturing, over- switchgears are used to supply the required elec- saw that manufacturing was in compliance with trical power to the I&C systems and components requirements, oversaw the factory acceptance tests of the units. at the manufacturer’s site, installation and test TVO made the first switchgear installations of runs at the power plant. The test runs of the valves the project in the 2010 annual maintenance. They were carried out in June according to the test pro- concerned an electrical system less important to gramme. Leak-tightness tests, valve movement safety. During the 2011 annual maintenance out- tests in cold and hot state, and testing with steam age of the Olkiluoto unit 2, TVO implemented the flow at 60% power of the plant were carried out ac- first switchgear replacement to systems important ceptably.

102 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 to safety so that the low-voltage switchgear in one the unit 1 were discovered. TVO verified the oper- of the plant’s four subsystems was replaced with ability of the installed valves by tests carried out the associated transformers. TVO continued the during the start-up of the Olkiluoto unit 2. As the project at the Olkiluoto unit 1 during the 2012 an- valves installed at the unit 2 were similar to the nual maintenance outage by replacing the switch- ones at the Olkiluoto unit 1, the experience from gear of one subsystem. the unit 1 suggested that there was a risk of the valves failing during the 2010–2011 operating Examples of latest incidents at the cycle. TVO decided to replace eight valves with old- Olkiluoto NPP (2010–2012) type valves. Two valves were replaced with new- type valves that had been modified after the fault Blowdown system failure at Olkiluoto 1 and was discovered. These two valves have a different repair outage at Olkiluoto 2 in June 2010 coating on the guide bush, and the piston has a big- The purpose of the blowdown system is to limit ger clearance. The valves operated during start-up the pressure in the reactor by letting out steam of the plant unit as well as in the tests performed from the reactor to the containment building if in November 2010. the normal route of the steam to the turbine is The fault did not endanger the safety of the not available. The system consists of a total of 14 plant or its surrounding environment. On the pipelines. Each pipeline has a valve, controlled by INES scale, the event was rated at level 1. the I&C system of the reactor, that opens when the reactor pressure must be reduced. The valves Use of a wrong fresh fuel delivery lot in can be opened either by an electric pilot valve or a fuel transfer planning at Olkiluoto unit 2 pressure-operated pilot valve. About one-fifth of the reactor fuel was to be re- In a test carried out just before the shutdown placed during the annual maintenance outage of of the Olkiluoto unit 1 for the annual mainte- Olkiluoto unit 2 in 2010. The fresh fuel assemblies nance outage in May 2010, two blowdown valves had been moved to the fuel pool in the reactor hall did not function as planned, so TVO decided to earlier in the spring to wait for their transfer to inspect their electrical pilot valves during the an- the reactor core. In early June 2010, TVO realised nual maintenance outage. The inspections revealed that 36 fuel assemblies of the wrong delivery lot that three electrical pilot valves were jammed. All had been transferred to the pool. These assemblies jammed pilot valves were of a new type. Five of were left in the fuel pool, and the correct assem- these valves had been installed at the Olkiluoto blies were transferred from the store to the reactor. unit 1 a year before. The five other electrical pilot The fuel assemblies are not of identical compo- valves were of the old type that has operated well sition, because different lots may differ from each for several years. Originally the decision to replace other, for example, with respect to their uranium the valves was taken for the purpose of making 235 content and neutron-moderating materials. It their maintenance easier. is important from the point of controlling reactiv- The jamming was caused by oxidation of the ity that the different properties of fuel assemblies plating material inside the guide bushes that are taken into account. In this case, the properties reduced the clearance between the valve piston of the wrong fuel assembly lot did not significantly and the guide bush and jammed the valve. TVO differ from those of the correct lot, which is why the removed the electrical pilot valves of a new type reactor safety would not have been compromised during the annual maintenance outage of the even if the subject lot of fuel had ended up in the Olkiluoto unit 1 and reinstalled the old-type valves. reactor. As a corrective action TVO developed its Operation of the blowdown system (overpressure procedures so that similar events can in the future protection of the reactor) was not at risk due to be prevented. The event was caused by an error the faults detected, because the pressure-operated in the document concerning the transfers of fresh pilot valves were in operating condition. fuel. Ten electrical pilot valves of a new type were The safety of the reactor or the employees was installed at the Olkiluoto unit 2 in the annual not compromised. On the INES scale, the event is maintenance in early May before the faults at rated at level 1.

103 STUK-B 164 Olkiluoto NPP u nits 1 and 2 u nder op eration ANNEX 3

Defects in the internal parts of to a condensation pool in the reactor containment blowdown system valves at Olkiluoto building. From the condensation pool, the heat is 2 and repair outage at Olkiluoto 1 transferred to the sea by other systems. TVO discovered in the inspections performed On the INES scale, the event was rated at during the annual maintenance outage of the level 1. Olkiluoto unit 2 in 2011 that there were cracks in the valve pistons of the system required for Deficiencies found in the operation overpressure protection of and residual heat re- of main steam isolation valves at moval from the primary circuit. The inspections Olkiluoto 1 and Olkiluoto 2 revealed other damage as well; for example, the During the 2012 annual outage of Olkiluoto 1, TVO hard chrome plating of the pilot cylinder had been found that one of the reactor’s main steam isola- damaged. However, the cracks and other damage tion valves would not have closed as planned when had not affected the operation of the valves; they required. A missing valve control conductor was had operated correctly in regular tests. revealed as the cause of the deficiency. The conduc- TVO replaced the parts of the worst damaged tor had been removed when four inner main steam valves during the annual maintenance. Not all isolation valves had been replaced in the 2010 an- damaged parts could be replaced due to an in- nual outage. The conductor had not been replaced sufficient inventory of spare parts. On the basis due to a modification design error. TVO carried of results from tests carried out during the pre- out additional checks and tests at both plant units ceding operating cycles, the valve manufactur- after the observation, and found the same defi- er’s assessment and analyses performed by VTT, ciency also at Olkiluoto 2. In a turbine automation TVO assessed that these valves were operable as renewal carried out in 2005, a conductor had been well. Immediate replacement of the parts was not unnecessarily removed. As a result, the same isola- deemed necessary. Nevertheless, STUK found, on tion valve as at Olkiluoto 1, and another isolation the basis of the reports produced by TVO regarding valve beside it, would not have closed automati- the faults discovered, that the original pistons and cally when required. pilot cylinders of the valves were approaching the Olkiluoto 1 and Olkiluoto 2 both have four end of their life span. It was nevertheless not likely steam lines for conveying the steam generated in that the valves would quickly become inoperable, the reactor to the turbine plant. Each steam line which is why STUK gave, on in June 2011, per- has two isolation valves, one inside the contain- mission to start up the Olkiluoto unit 2 after the ment wall and one on the outside. Their purpose is annual maintenance outage. STUK required that to close the steam lines in certain transient and ac- new spare parts should be changed to the valves cident situations, thus isolating the reactor and its immediately when a sufficient number of new containment in order to retain radioactivity within spares has been received from the manufacturer. the containment. The missing control conductors The requirement was to carry out the replacement did not belong to these main valves. Instead, the by 15 September. concerned isolation valves were located side by Olkiluoto unit 1 is using similar valves, which side outside the containment on a pipeline that is is why STUK required that TVO must also inspect used to let the steam released from under the valve them. During the repair outage of 26–29 June piston of closing pressure-operated isolation valves 2011, damage was observed in the pistons of four into the containment condensation pool. These two valves and in the pilot cylinders of 11 valves. TVO external isolation valves are located on a closed replaced them with flawless spare parts. circuit, which means that steam and radioactive The faulty valves were part of a system in- substances carried by the steam could not have tended for protecting the nuclear reactor against been released outside the containment even if the overpressure and for removing its residual heat in valves had been left open. a situation where the steam generated in the reac- The events did not put the safety of the plant tor cannot enter the turbine plant. The necessary or the environment at risk, but revealed deficien- number of valves is opened, and the steam generat- cies in modification planning and the coverage of ed in the reactor is led along the system’s pipelines testing. TVO installed the missing conductors im-

104 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 mediately after the events were detected. TVO will The issues addressed in the assessment and also investigate the coverage of testing more exten- the related evaluation criteria are set forth in the sively and improve the process used to ensure that nuclear energy and radiation safety legislation and modifications are ready to be implemented. the regulations issued thereunder. Based on the The events of both plant units were rated as assessment, STUK considered that the Olkiluoto INES category 1. The classification is based on a Nuclear Power Plant units 1 and 2 meet the set modification error. safety requirements for operational nuclear power plants, the emergency preparedness arrangements Periodic safety reviews at the Olkiluoto NPP are sufficient and the necessary control to prevent During the years 1996–1998 the overall safety re- the proliferation of nuclear weapons has been view of the Olkiluoto plant was carried out by the appropriately arranged. The physical protection licensee and independently by STUK in connection of the Olkiluoto nuclear power plant was not yet to the renewal of operating licences of nuclear pow- completely in compliance with the requirements er plant units. The safety documentation, includ- of Government Decree 734/2008, which came into ing safety assessments done by the licensee, was force in December 2008. Further requirements submitted to STUK at the end of 1996. In addi- concerning this issue based also on the principle of tion to the review of the licensing documents such continuous improvement were included in the deci- as Final Safety Analysis Report, STUK also made sion relating to the periodic safety review. an independent safety assessment. The statement The safety of the Olkiluoto nuclear power plant of STUK was given to the Ministry of Trade and was assessed in compliance with the Government Industry in June 1998. As regards radiation and Decree on the Safety of Nuclear Power Plants nuclear safety, the main conclusions in the state- (733/2008), which came into force in 2008. The ment were that the conditions of the Finnish nu- decree notes that existing nuclear power plants clear energy legislation are complied with. need not meet all the requirements set out for new The latest overall safety review of the Olkiluoto plants. Most of the design bases pertaining to the plant took place in 2007–2009 in connection of Olkiluoto 1 and 2 nuclear power plant units were the periodic safety review. The operating licence set in the 1970s. Substantial modernisations have for Olkiluoto NPP units 1 and 2, required that a been carried out at the Olkiluoto 1 and 2 nuclear comprehensive periodic safety review (PSR) shall power plant units since their commissioning to be carried out by the end of 2008. The operating improve safety. This is in line with the principle licence also covers the interim storage facilities of continuous improvement of safety provided in for spent fuel and medium and low activity opera- section 7 a of the Nuclear Energy Act. The safety tional waste, so these facilities were also included of the plant will be further improved during the in the PSR. Regulatory guide YVL 1.1 specifies current operating licence period. Based on the the contents of the PSR. For a separate periodic periodic safety review, TVO submitted to STUK safety review, STUK shall be provided with similar action plans for the observed points requiring im- safety-related reports as in applying for the operat- provement. STUK included also some additional ing licence. requirements in the decision relating to the peri- TVO began preparations for the periodic safety odic safety review. Systematic assessment and de- review a few years after the current operating velopment of the diversity principle was required, licence was granted. The PSR documentation was including investigation of possibilities for residual submitted to STUK for approval in the end of 2008. heat removal to be independent of seawater. TVO STUK made a decision concerning the PSR in submitted a report regarding the adequacy of the October 2009. In the STUK’s decision the licensee’s diversification at the plants and an action plan for PSR was approved as a comprehensive periodic developing the plants at the end of 2010. STUK safety review according to the licence condition. approved the report in 2012. Another require- The decision included also STUK’s safety assess- ment considered plant modifications to improve ment which provided a summary of the reviews, safety in situations involving spurious opening inspections and continuous oversight carried out of the turbine bypass valves. TVO has submitted by STUK.

105 STUK-B 164 Olkiluoto NPP u nits 1 and 2 u nder op eration ANNEX 3 required report and STUK has approved TVO’s dis- Safety assessments and improvements quisition and action plans to improve the situation. based on the lessons learnt from As a summary of the review of the issues and TEPCO Fukushima Dai-ichi accident documentation pertaining to the periodic safety review and the continuous oversight results, STUK Natural hazards noted that the safety of the Olkiluoto nuclear pow- Safety margins were assessed by the licensee and er plant units 1 and 2 is sufficient and the licensee reviewed by STUK. Based on the results, STUK re- utilises the necessary arrangements to continue quired further clarifications on the following main the safe operation of the plants. points: • seismic resistance of spent fuel pools including Planned and ongoing activities to situations with water temperature exceeding improve safety at the Olkiluoto NPP the design bases; and In Finland, the continuous safety assessment and • seismic resistance of fire fighting systems. enhancement approach is presented in the nuclear legislation. Actions for safety enhancement are to The licensee of the Olkiluoto NPP was also re- be taken whenever they can be regarded as justi- quested to carry out a more detailed assessment on fied, considering operating experience, the results the effects of exceptionally high seawater level on of safety research and the advancement of science the cooling systems of the spent fuel interim stor- and technology. The implementation of safety im- age and their electric power supply. Cooling system provements has been a continuing process at the pumps are situated at the +0.5 m level. The spent Olkiluoto nuclear power plant units 1 and 2 since fuel interim storage is designed as watertight up their commissioning and there exists no urgent the seawater level +1.2 m. At higher seawater lev- need to upgrade the safety of these plant units in els some seepage of water through the soil to the the context of the Convention. drainage system is anticipated. According to the There are several ongoing and planned safe- licensee, the seepage would be stable and slow ty upgrading measures at the Olkiluoto nuclear and the water could be removed with submersible power plant. For example diversification of reac- pumps. Fast flooding of the interim storage would tor water level measurements and construction of be possible through the doors if the seawater level an emergency control room are under design. In exceeds +3.5 m and through the seam between the addition, in the last periodic safety review, STUK seawater pumping station and seawater pipe cul- requested TVO to perform a comprehensive survey vert at the level +2.5 m. The licensee has submit- on the sufficiency of diversification at the Olkiluoto ted plans for tightening the aforementioned seam units 1 and 2 and a plan on measures to develop and submitted by the end of 2012 plans for further diversification by the end of 2010. improving the protection of the interim storage The reactor water level measurement system against flooding, including increase of the capacity consists of four parallel subsystems, two of which of the submersible pumps. are sufficient for implementing the protection func- tion (from high and low level). The subsystems are Design issues based on differential pressure measurement. TVO At the Olkiluoto units 1 and 2, sea water is the pri- has studied possibilities to supplement the cur- mary ultimate heat sink and an alternative heat rently used low level measurement system with sink exists only partially. Both units can evapo- another system based on a different measuring rate residual heat from the reactor core to atmos- principle. TVO’s plans to implement the modifica- phere by conducting the steam produced inside tion has been delayed. The current plan is to install the reactor pressure vessel to the condensation the new devices for test use in annual outages 2015 pool through the safety relief valves, by letting the and 2016. condensation pool to boil, and by venting the steam

106 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 from the containment to atmosphere through the component failures. Also one extra diesel generator filtered venting system. However, the systems re- is under consideration to supply water to reactor in quired to pump water into the reactor pressure case of loss of other AC power. vessel are either dependent on the sea water based At the Olkiluoto units 1 and 2, the depletion component cooling systems or on the condensation times of DC batteries are well above 10 h, in some pool water, which means that the complete loss of cases tens of hours. It is possible to charge the bat- sea water as the ultimate heat sink will eventually teries using the AC power sources. DC batteries prevent the supply of water to the reactor pressure supplying the severe accident monitoring systems vessel. can be also charged by mobile generators. The Licensee is planning plant modifications on licensee is investigating the possibilities for fixed the current residual heat removal chain to de- connection points for recharging of all safety im- crease the dependence on the sea water cooling. portant batteries using transportable power gen- A modification in the auxiliary feed water system erators. is planned to enable cooling of the components At the Olkiluoto units 1 and 2, the licensee has by demineralised water in addition to sea water evaluated that water injection into the pool and based cooling chain. By this modification system boiling of the pool water could be used as an alter- can remain operational for a significant period of native means to remove decay heat from the pools time even during the loss of the primary ultimate inside the reactor building. To support monitoring heat sink (sea water). Modifications are scheduled of the water level in the reactor building spent fuel for 2014-2015. In addition, an independent way pools, there is a plan to equip the fuel pools with a of pumping water to the reactor pressure vessel level measurement system. Possibilities for add- is being planned by the licensee in case of loss of ing makeup water from the fire fighting system to AC power. The arrangement will be based on the the pools from safe locations will be provided. The fire fighting water system with additional booster pool water level indications will also be routed to pumps and an own diesel aggregate. Also a steam those locations. Modifications will be done during driven pump is considered for the early phases of 2013-2014. External junctions to the interim spent the accident to cool reactor in high pressure. fuel storage pool (outside the reactor buildings) At the Olkiluoto units 1 and 2, the current AC water system will be added at the Olkiluoto NPP power supply systems include connections to 400 during the enlargement project of spent fuel stor- kV and 110 kV power grids, main generator (house age in 2013. Feed of water to the fuel storage pools load operation), four emergency diesel generators will be possible from fire-fighting vehicle via those per unit, a gas turbine, a dedicated connection to junctions. a nearby hydropower plant, and the possibility to At the Olkiluoto units 1 and 2, the licensee supply electricity from the neighbouring NPP unit. started the investigation of needs and targets for The licensee has decided to renew all the eight mobile power supply in autumn 2011. Investigation emergency diesel generators. Several plans, sur- includes also renewal of the present mobile SAM veys and studies have been prepared for this pro- diesel generators. Five aggregates stored on the ject and the investment decision was made in May site are under consideration. Enhancing charging 2013. The renewal plan includes several safety of batteries has also been found feasible to improve improvements. First of all, the new EDGs would be the availability of DC power. The licensee is inves- equipped with two diverse component cooling sys- tigating the possibilities for fixed connection points tems. The primary EDG cooling would be provided for recharging of the safety important batteries us- by the sea water based cooling system, similar to ing transportable power generators. Investigation present EDGs units. An alternative, automatically of needs and targets for mobile power supply has activated air based cooling system would be added been started in autumn 2011 and is expected to be to cope with the loss of sea water situations. This completed by the end of 2012. Procurement of the would provide extra protection against external devices and needed modifications are expected to hazards, internal hazards such as fires, as well as begin in 2013.

107 STUK-B 164 Olkiluoto NPP u nits 1 and 2 u nder op eration ANNEX 3

Severe accident management view to the current requirements. In conjunction A comprehensive severe accident management with assessing the safety of the expansion, STUK (SAM) strategy has been developed and imple- inspected the needs to update the earlier design mented at the Olkiluoto units 1 and 2 during basis and safety analyses, the resources and op- 1980’s and 1990’s after the accidents in TMI and erational methods of TVO’s project organisation, Chernobyl (see above). These strategies are based the structural design basis of the storage, as well on ensuring the containment integrity which is re- as the methods with which TVO will ensure the quired in the existing national regulations. STUK safety of the storage in operation. Following its in- has reviewed these strategies and has made in- spections, STUK found that the storage expansion spections in all stages of implementation. meets the safety requirements. STUK has also re- As a result of the studies made after the viewed the plans for the systems that will change TEPCO Fukushima Dai-ichi accident, no major with the expansion. The design and implementa- changes at the plants are considered necessary. tion of construction engineering structures are However, the licensee is expected to consider also overseen by an inspection organisation approved spent fuel pools in the SAM procedures as well as by STUK. STUK has been overseeing and guiding any implications on them possibly arising from the work of the inspection organisation. simultaneous multi unit accidents. In addition, there are many actions related to the update of the Renewal of the diesel generators emergency plans. TVO has investigated the possibilities for replacing Hydrogen leakages out of the containment dur- all current emergency diesel generators (EDGs) of ing severe accidents has been analysed for all the Olkiluoto units 1 and 2 with their auxiliary Olkiluoto NPP units, and the results show that de- systems to correspond with the changed need for sign leakages do not cause a threat to the contain- power, taking also into account any increases in ment integrity. For spent fuel pools, the approach the need for power due to possible future plant in Finland is to “practically eliminate” the possibil- modifications as well as the lessons learnt from ity of fuel damage. The possibility of top venting of the TEPCO Fukushima Dai-ichi accident in re- reactor hall will be designed at the Olkiluoto units lation to securing the power supply. The nuclear 1 and 2 in 2013 for the steam release in case of safety requirements dictate that a power margin spent fuel pool boiling. Hydrogen possibly formed of at least 10% is available in all load conditions. in the spent fuel pools could be exhausted through Furthermore, both main components of the EDGs this route as well. (the diesel engine and the generator) are old mod- els, whose development and manufacture has been Enlargening of the spent fuel storage discontinued, and the availability of spare parts TVO is in the process of expanding capacity of the and the supplier’s technical support are declining. the spent fuel interim storage (the so-called KPA The purpose of the emergency diesel generators storage) at Olkiluoto by three additional pools, and and their associated auxiliary systems is to sup- the storage structures will also be modified at the ply electrical power to the 660 V emergency power same time to comply with the current safety re- system in case of loss of supply from the 6.6 kV quirements. The current KPA storage capacity in main bar. Both plants have four subsystems, and Olkiluoto will be sufficient until 2014, and the ex- each subsystem has its own standby diesel genera- pansion will increase the capacity for the spent tor. Replacement of the diesel generators will also fuel coming from the Olkiluoto plant units 1, 2 mean that the main switchgear in the 660 V emer- and 3. TVO submitted the documentation regard- gency power network has to be replaced; this will ing expansion of the storage to STUK for approval be done as part of the replacement of low-voltage at the end of 2009. The extension of the storage is switchgear as a modification project separate from designed to fulfil the current safety requirements, the replacement of the EDGs. the most significant of which are its ability to with- The intention is to implement the EDG replace- stand the crash of a large airliner and its seismic ment project during the normal operation of the resistance. At the same time, the structures of the plant units as far as possible. According to the existing part of the storage will be modified with a plan, the new EDGs will be installed and commis-

108 ANNEX 3 Olkiluoto NPP u nits 1 and 2 u nder op eration STUK-B 164 sioned during power operation so that one new Construction of an emergency control room EDG is installed to both plant units during one Pursuant to a Government Decree, a nuclear power power operation cycle. For this purpose, a ninth plant shall have an emergency control room inde- EDG unit has to be constructed to replace any one pendent of the main control room, and the neces- of the current EDGs of the Olkiluoto units 1 or 2. sary local control systems for shutting down and In the future, the ninth EDG can be connected to cooling the nuclear reactor, and for removing re- replace an EDG undergoing periodic maintenance sidual heat from the nuclear reactor and spent fuel at the Olkiluoto units 1 or 2, or it can replace a stored at the plant in a situation where operations failed EDG. A new building will be constructed for in the main control room are not possible. the ninth EDG, while the replacement EDGs will TVO is in the process of constructing emergency be installed at the same premises where the cur- control rooms for the Olkiluoto units currently in rent units are located. operation in compliance with the requirements set In late autumn 2011, TVO submitted a con- out in STUK’s implementation decision regarding ceptual design plan regarding the replacement of Guide YVL 5.5 and in the periodic safety review of EDGs to STUK for approval. The conceptual design the Olkiluoto NPP. The project is currently in its plan was approved by STUK. According to the pre- pre-planning phase, and STUK has reviewed and liminary schedule, the EDGs will be installed and approved the conceptual design plan of the emer- commissioned during 2016–2020. gency control rooms in 2012.

109 STUK-B 164

ANNEX 4 Olkiluoto NPP unit 3 under construction

Licensing steps key delivery is provided by the Consortium Areva Decision-in-Principle procedure was carried out NP and Siemens. The technical requirements during the period November 2000 – May 2002 when for Olkiluoto unit 3 were specified by using the Teollisuuden Voima Oyj (TVO) applied a Decision- European Utility Requirements (EUR) document in-Principle for the fifth NPP unit in Finland and as a reference. TVO’s specifications complemented the Government approved it and the Parliament the EUR mainly in those points where Finnish confirmed the approval. Construction Licence ap- requirements are more stringent. STUK gave its plication for the Olkiluoto unit 3 was submitted by statement and safety assessment in January 2005 TVO to the Ministry of Trade and Industry (pre- based on the review of the licensing documenta- decessor of the Ministry of Employment and the tion and the Government issued the Construction Economy) in January 2004. The new unit, Olkiluoto Licence in February 2005. 3 is a 1600 MWe European Pressurised Water Construction of the Olkiluoto unit 3 still con- Reactor (EPR), the design of which is based on the tinues. In the turbine island, Siemens has started French N4 and German Konvoi type PWR’s. A turn cold commissioning of the systems after finalising

Figure 22. Olkiluoto NPP unit 3 construction site in April 2013. Source: TVO.

110 ANNEX 4 Olkiluoto NPP ut ni 3 u nder cn o struction STUK-B 164 construction and installation works. In the nu- vendor and the licensee are now finalising plans clear island, erection of systems, structures and for I&C system architecture as well as answers for components continues. Next major licensing step STUK’s clarification requests. is the Operating Licence. Operating Licence is needed prior to loading nuclear fuel into the reac- Regulatory oversight tor core. IAEA has agreed to carry out a pre-OS- During the construction, STUK oversees the pro- ART (Operational Safety Review Team) mission to ject very comprehensively. The licensee’s perfor- Olkiluoto NPP before core loading. mance is evaluated via Construction Inspection Program. The purpose of the program is to verify Challenges that the performance and organisation of the li- Currently, the licensee and the vendor don’t have censee ensure high quality construction and im- commonly approved schedule for the project. The plementation in accordance with the approved de- licensee has given a notice that the start of the signs while complying with the regulations and commercial electricity production of the Olkiluoto STUK’s decisions. Under Construction Inspection unit 3 may be postponed until year 2016. There Program STUK has performed around 15 inspec- are certain factors that have affected greatly tions every year. Some of the inspections are unan- the project progress. Olkiluoto unit 3 is the first nounced inspections. European Pressurised Reactor (EPR) being con- In addition to Construction Inspection structed. Construction of the unit started after a Programme, STUK has strong on-site presence long break in nuclear power plant construction in by the resident inspectors at the construction site. Europe, which had resulted in loss of experienced There are three to four resident inspectors dedi- and qualified engineering and manufacturing re- cated for Olkiluoto unit 3 project. This provides sources. Lack of knowledge on Finnish regulatory STUK constant flow of information and oversight framework and safety requirements, insufficient capabilities and gives additional information on completion of the design prior to construction, licensee’s activities. STUK has therefore also very some difficulties with advanced manufacturing quick ability to response to any immediate safety and construction technologies and lacks in safety concern or incident with short notice. Findings culture in the earlier phase of construction works made by resident inspectors are also important at site have been challenging aspects in the project inputs for the construction inspection programme and caused delays. On the other hand parties have inspections. succeeded to find deviations induced during the The construction of a nuclear facility shall not project and the end products have finally fulfilled begin before the Government has granted the quality, performance and safety requirements. Construction Licence. After that, prior to start The issue which at the moment set also the manufacturing, installation or commissioning of timeline of the project is the licensing of I&C archi- the system, structure or component, STUK’s ap- tecture and systems. Using of integrated, software provals for the detailed design or plans are needed. based I&C platforms sets new requirements for STUK also approves manufacturers of nuclear designing, safety analyses as well as for implemen- pressure equipment for their duties and inspection tation and testing of the systems. Configuration organisations and testing organisations for duties and requirement management and verification & pertaining to the control of pressure equipment validation actions are more essential role during at nuclear facilities. During the Olkiluoto unit these phases than earlier when analog systems 3 project, STUK has reviewed more than 14000 were used. The main issues where STUK has documents – about 9000 of them are submitted to asked more clarification concern defining and man- STUK for approval. agement of interfaces of different I&C systems so STUK also inspects the compliance of the de- that failure of one system can’t disturb other sys- sign and manufacturing of mechanical components tems. STUK has also asked more clarification how and structures. Inspections are performed dur- possible spurious actions are taken into account in ing and after the manufacturing in manufactur- the design and corresponding safety analyses. The ers’ premises and at the site after installation

111 STUK-B 164 Olkiluoto NPP ut ni 3 u nder cn o struction ANNEX 4 and during commissioning. In lower safety class- External conditions in Finland are moderate. es these inspections are conducted by Inspection No destructive earthquakes or tsunami waves have Organisations. been observed. Storms are not comparable to tropi- Based on the findings made during the techni- cal cyclones and strong tornadoes are quite rare. cal inspections, inspections under construction in- Olkiluoto unit 3 fulfils the current regulatory re- spection programme, document reviews and other quirements concerning external events. The design visits during construction, STUK prepares annu- basis of Olkiluoto unit 3 for external events has ally a comprehensive safety evaluation how safety been selected conservatively in the design phase. aspects are fulfilled and taken into account during The design basis covers earthquakes, internal and the construction. The experience has shown that external flooding, extreme weather and other natu- STUK’s practice to oversee the project in all level ral hazards (like snowstorms, frazil ice formation of activities has been effective way to find possible and impurities in the seawater) as well as human weak points and deviations in early phase of the induced hazards. The design values correspond to project. Translations of annual report can be found return periods of up to 100 000 years and much from the STUK’s website. longer for events with “cliff edge” type consequenc- es. As the estimated conditions corresponding to Safety assessments based on such long return periods involve large uncertain- the lessons learnt from TEPCO ties, considerable physical margins to the largest Fukushima Dai-ichi accident values observed in the neighbourhood of the site Following the accident at the TEPCO Fukushima have also been ensured. Dai-ichi nuclear power plant on the 11th of March The ultimate heat sink of the Olkiluoto unit 3 is in 2011, safety assessment of Olkiluoto unit 3 was the sea. In case of the total loss of the availability initiated. The topics included the preparedness of sea water for cooling, the residual heat from the against loss of electric power supply, loss of ulti- reactor core would be released to the atmosphere mate heat sink and extreme natural phenomena. via the steam generators. During refuelling outage As being a unit under construction, any immediate the containment filtered venting could be used. actions were not necessary, but STUK required the Filtered venting system is not an original safety licensee to carry out additional assessment and feature of EPR concept but it was required by present an action plan for safety improvements. STUK in an early phase of the conceptual design Assessment was conducted and reported by the of Olkiluoto unit 3 to ensure the pressure manage- licensee to STUK on 15 December 2011. STUK ment of the containment during severe accidents. reviewed the assessment and made decision on 19 The licensee has assessed possibilities to imple- July 2012 on the suggested safety improvements ment external feed water connections to the steam and additional analyses. generator secondary side, connections to external AC power supply and external make-up water injection into the reactor cooling system during refuelling outages in order to have independent means to fulfil residual heat removal function in case plant’s normal systems are lost. STUK is cur- rently evaluating licensee’s plans. In the fuel building, the spent fuel pools could be cooled by evaporation. The possibility to use fire water systems and boiling of the pool water has been evaluated. Additional mobile pumps to provide water injection into the fire fighting water system are to be acquired before the start of opera- tion of the Olkiluoto unit 3. The needed external connection points, as well as temperature and level Figure 23. STUK’s resident inspector performing con- struction inspection for primary circuit piping.

112 ANNEX 4 Olkiluoto NPP ut ni 3 u nder cn o struction STUK-B 164 measurements are included in the design of the For uninterrupted power supplies, there are fuel building systems. Additional measurements separate and diversified 2 h and 12 h battery to monitor the water level in the pools are to be backed power supply systems. The first set of implemented. batteries supplies all electrical equipment which The current AC power supply systems of the require uninterruptible power in the nuclear is- Olkiluoto unit 3 include connections to 400 kV land and the second set of batteries supplies loads and 110 kV power grids, main generator (house which are important in case of a severe accident. load operation), four emergency diesel generators The licensee evaluates that there is no need for (EDGs), two station black out (SBO) diesel gen- upgrading the battery capacity. erators, a gas turbine and the possibility to supply Severe accidents have been considered in the electricity from the neighbouring NPP units via original design of the Olkiluoto unit 3. STUK has 400 kV switchyard. To ensure long autonomy of reviewed the overall SAM strategy and the ap- SBO diesels the licensee has planed to add pos- proach has been accepted. No changes to this ap- sibilities to move fuel from EDG storage tanks to proach are expected based on current knowledge SBO diesels. from the TEPCO Fukushima Dai-ichi accident.

113 STUK-B 164

ANNEX 5 Olkiluoto NPP unit 4 and Hanhikivi NPP unit 1 in planning phase

Environmental Impact Assessment of new candidate site being 20–30 km from the borderline nuclear power plants and candidate sites of Sweden. Fennovoima prepared an EIA pro- In 2007, initiatives for building additional nucle- gramme and subsequently an EIA report for three ar power plant units in Finland were announced. (originally four) alternative new candidate sites in Environmental Impact Assessment (EIA) was car- 2007–2009. ried out according to EIA legislation for the pos- The EIA process did not reveal any major nu- sible Olkiluoto 4 and Loviisa 3 units in 2007–2009. clear or radiation safety issues as regards the pro- The Competent Authority for EIA procedure for posed new NPP sites or new units on the existing NPP’s in Finland is the Ministry of Employment sites. EIA is a legal process to cope comprehensive- and the Economy. ly with the environmental issues depending on the A new nuclear power company, Fennovoima Oy, specific site (e.g. sea environment and eutrophica- was founded in 2007. The company started a pre- tion, special natural species and phenomena, biodi- liminary site survey process, mainly on the coast versity, Natura natural reserve assessment, fisher- of the Gulf of Bothnia (the northern gulf of the ies, salmon migration, combined heat and power Baltic Sea) and on the eastern Gulf of Finland (the production) and to increase the opportunity for eastern gulf of the Baltic Sea), the northernmost citizens and other stakeholders to receive informa-

Figure 24. Hanhikivi site in Pyhäjoki selected for Fennovoima new NPP (FH-1). Source: Fennovoima.

114 ANNEX 5 Olkiluoto NPP ut ni 4 and Hah n ikivi NPP ut ni 1 in panl n ing ph ase STUK-B 164 tion, become involved in the planning and express nuclear facilities according to the safety require- their satetments and opinions on the project. ments. More detailed evaluation of the site related Comments were requested from altogether nine factors will be conducted and site characterisation countries near the Baltic See by the Finnish is accepted in connection with the Construction Environmental Ministry on the basis of so called Licence process. Espoo convention. Several comments from e.g. Fennovoima completed site selection process Estonia, Sweden and Germany were given and in October 2011 by selecting Hanhikivi site in considered by the Finnish authorities. Additionally, Pyhäjoki. The company stated that the main tech- the Austrian Government as a party of the Espoo nical arguments for site selection were bedrock convention sent their statement on each EIA and intackness, lower seismicity, shorter cooling water requested for consultation in Finland. Thus, sub- tunnels and population density. sequent meetings were arranged in 2008–2009 at the Finnish Ministry of the Environment where Decisions-in-Principle and safety a Finnish delegation of experts from the utility assessments of new nuclear power plant units concerned, STUK and the Ministry of Employment Three new nuclear power plant units have been and the Economy gave detailed explanations to the under consideration in Finland (see more details questions provided. of the licensing process under Articles 7 and 17). Separate applications for the Decision-in- TVO submitted application for a Decision-in- Principle for new NPP units were submitted to Principle (DiP) to the Ministry of Employment and the Government in 2008 and 2009 by TVO, Fortum the Economy in 2008, Fennovoima and Fortum in and Fennovoima. The relevant site-related factors 2009. In addition, two DiP applications by Posiva potentially affecting the safety of a the planned Oy have been handled for the expansion of the new NPP units and the related nuclear facilities planned capacity of spent fuel repository for during their projected lifetime were evaluated for Olkiluoto 4 and Loviisa 3 units. The applications the existing Loviisa and Olkiluoto sites and for for NPP units were accompanied by documents of a the alternative new sites at Pyhäjoki, Simo and total of seven alternative plant designs. Ruotsinpyhtää proposed by Fennovoima. In late In the Decision-in-Principle (DiP) the Govern­ 2009, Fennovoima removed the Ruotsinpyhtää site ment judges whether the proposed use of nuclear from its application for the Decision-in-Principle. energy is in line with the overall good of society. The evaluations were reviewed by STUK and other STUK gave the Ministry of Employment and the expert organisations in their respective fields. In Economy preliminary safety assessments of all addition to the Finnish regulations, IAEA Safety Decision-in-Principle applications in 2009. STUK’s Requirements and Safety Guides and WENRA re- preliminary safety assessments consisted of an as- quirements were considered in the review. sessment of the safety of the plant alternatives and Specific issues regarding the new sites are the the sites as well as of an assessment of the organi- size of precautionary action zone (5–6 km radius sations, expertise and the quality management of in Finland), the limitation of maximum population the applicant. The assessments also covered the within it which may be affected in a severe acci- physical protection and emergency preparedness dent situation and the possibility to evacuate the arrangements, nuclear fuel and nuclear waste population. According to the Finnish regulations, management, nuclear liability and non-prolifera- an early evacuation before an expected release tion. STUK stated in its preliminary safety assess- shall be possible within a time of four hours from ment whether any factors have arisen indicating the evacuation decision. The population in 2010 in a lack of sufficient prerequisites for constructing the vicinity of the Finnish candidate sites is inter- a nuclear facility as prescribed in the Nuclear nationally compared relatively small (maximum of Energy Act. Safety assessment was based on the 3000 inhabitants up to 6 km from the site at Simo). Government Decrees issued under the Nuclear According to STUK’s preliminary safety as- Energy Act. Furthermore, STUK took a stand on sessments, no site related factors were found at the possibility of fulfilling other requirements laid any of the sites which would prevent building the down in legislation and YVL Guides as regards proposed new NPP units and the related other the issues to be reviewed by STUK. The aim of

115 STUK-B 164 Olkiluoto NPP ut ni 4 and Hah n ikivi NPP ut ni 1 in panl n ing ph ase ANNEX 5 the preliminary safety assessment was to find any tor to Loviisa site (Loviisa unit 3), as well as the “show stoppers” in sites, organisations or plant DiP application for expanding the capacity of the design alternatives. Seven different plant design spent fuel disposal facility to include also the spent alternatives were assessed during the prelimi- fuel from the Loviisa unit 3 was rejected. nary safety assessment period: ABWR (Toshiba- According to the Nuclear Energy Act, the grant- Westinghouse), AES-2006 (), ed DiP’s were sent without delay to the Parliament APWR (Mitsubishi Heavy Industry), APR-1400 for confirmation. The Parliament may reverse the (Korean Hydro and Nuclear Power), ESBWR (GE Decision-in-Principle as such or may decide that it Hitachi), EPR (AREVA) and KERENA (AREVA). remains in force as such. After the hearings in the Most of the plant alternatives reviewed in the all main permanent committees, the Parliament STUK’s preliminary safety assessments did not ratified both granted NPP applications on the meet Finnish safety requirements as such. The 1st of July 2010. The both Decisions-in-Principle nature and the extent of the required modifica- for new reactors state that the construction li- tions vary between the plant alternatives. Some cence shall be applied within five years from the plant alternatives would only require fairly minor Parliaments confirmation. This sets the schedule modifications; some would require more extensive for Fennovoima and TVO to conclude their prepa- structural modifications. The required technical rations for the construction licence applications to solutions are still open for some alternatives. the Government by mid 2015. All DiP applications were handled simultane- ously and in May 2010 the Government granted Preparations for the construction two Decisions-in-Principle, one to Teollisuuden licence phase Voima Oyj (TVO) and another to Fennovoima Oy. According to the Nuclear Energy Act, the applicant TVO’s DiP was granted according to the applica- may ask advice or sent plans for STUK’s review be- tion to build Olkiluoto unit 4 (OL4), single reac- fore the applications are filed to the Government. tor with maximum output of 4600 MWh. In the With this mandate, the utilities and STUK have Fennovoima’s case Government granted DiP only had meetings to be prepared for the construction li- for a single reactor with maximum reactor power of cence safety assessment process. STUK has organ- 4900 MWth, although Fennovoima applied to build ised seminars with licence applicants on construc- one or two reactors with maximum reactor power tion licence application requirements in relation to of 4300–6800 MWth. the plant design processes and shared the lessons The Government also granted a Decision-in- learned from the Olkiluoto unit 3 construction pro- Principle for Olkiluoto unit 4 spent fuel final ject as well as had seminars on requirement man- disposal, applied by the spent fuel management agement. Process system and plant engineering company Posiva Oy. For Fennovoima’s spent fuel (layout) design maturity in PSAR phase is domi- disposal, the Government gave two options. By mid nating factor for successful construction licence ap- 2016, Fennovoima shall present an co-operation plication review. Also both applicants have sent nu- agreement of spent fuel final disposal with TVO clear safety related bid requirements to STUK for and Fortum (the owners of Posiva) or start its information. These are the first steps for STUK to own EIA process for the spent fuel final disposal. prepare regulatory project for construction licence Regardless of the option chosen a separate DiP review phase. will later be required for disposing of the spent The main challenge for the upcoming construc- fuel from Fennovoima’s planned reactor unit. For tion licence application review is to conclude the this DiP process also the corresponding EIA report renewal process of the legislation and the regula- needs to be updated or prepared for a possible new tory guides – new YVL guides. Another challenge site. for STUK is to recruit the needed competent regu- At the same time the Government rejected latory staff if two new NPP projects will commence Fortum’s DiP application to construct a new reac- simultaneously.

116 STUK-B 164

ANNEX 6 Implementation of the IAEA Action Plan on Nuclear Safety

The transparency and international co-operation review on the report was completed by April 2012. are one of the corner stones in the Finnish nu- The recommendations of the EU peer review have clear safety policy. Finland has signed the inter- been taken into account in the regulatory deci- national conventions and treaties aiming on safe sions and will be considered in the development and peaceful use of nuclear energy. After the of national regulations. In addition, Finland par- TEPCO Fukushima Dai-ichi accident, Finland ticipated in the second Extraordinary Meeting of signed among 130 other countries in the General the Convention of Nuclear Safety (CNS) in August Conference in September 2011 the IAEA Action 2012 and prepared a report introducing national Plan. The twelve main actions included in the actions in Finland initiated as a result of the IAEA Action Plan and the related Finnish meas- TEPCO Fukushima Dai-ichi accident. STUK has ures are discussed in this Annex. prepared a National Action Plan in the framework of EU stress tests addressing the measures initi- Safety assessments in the light of the ated on a national level and at the nuclear power accident at TEPCO’s Fukushima Daiichi NPP plants as a result of the TEPCO Fukushima Dai- Undertake assessment of the safety vulnera- ichi accident. The National Action Plan takes into bilities of nuclear power plants in the light of account the national safety assessments and relat- lessons learned to date from the accident ed regulatory decisions as well as the recommenda- Following the accident at the TEPCO tions from the EU stress tests and Extraordinary Fukushima Dai-ichi nuclear power plant on the CNS. All STUK’s related decisions, the national 11th of March in 2011, safety assessments in report to European Commission, the report to the Finland were initiated after STUK received a Extraordinary CNS, and the National Action Plan letter from the Ministry of Employment and the have been published on STUK’s website. Economy (MEE) on 15 March 2011. The Ministry Based on the results of assessments conducted asked STUK to carry out a study on how the in Finland to date, it is concluded that no such Finnish NPPs have prepared against loss of elec- hazards or deficiencies have been found that would tric power supply and extreme natural phenomena require immediate actions at the Finnish NPPs. in order to ensure nuclear safety. STUK asked the Areas where safety can be further enhanced have licensees to carry out assessments and submitted been identified and there are plans on how to the study report to MEE on 16 May 2011. Although address these areas. The experiences from the immediate actions were not considered necessary, TEPCO Fukushima Dai-ichi accident are also tak- STUK required the licensees to carry out addi- en into consideration in the ongoing renewal of the tional assessments and present action plans for legislation and Finnish Regulatory Guides (YVL safety improvements. Assessments were conducted Guides). and reported by the Finnish licensees to STUK on 15 December 2011. STUK has reviewed the results IAEA peer reviews of national assessments, and made licensee specific Strengthen IAEA peer reviews in order to decisions on 19 July 2012 on the suggested safety maximize the benefits to Member States improvements and additional analyses. Finland regularly hosts international peer re- Finland also participated in the EU Stress Tests views and also offers its experts for the review in and submitted the national report to European other countries. Finland also supports activities to Commission at the end of 2011. An EU level peer improve peer review services and has already par-

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ticipated in the development of IAEA’s peer review gency plan was prepared. The development has services (e.g. IRRS and the OSART missions for been a continuous process since then. The require- construction). ments for off-site plans and activities in a radia- The latest peer reviews in Finland are the fol- tion emergency are provided for in the Decree of lowing: the Ministry of the Interior issued in 2011. Off-site • IAEA OSART safety review at Loviisa NPP in emergency plans are prepared by regional rescue March 2007, with a follow-up review in July authorities. Legislation and plans define clearly 2008 the roles and responsibilities of stakeholders hav- • WANO peer review at Loviisa NPP in March ing a role in an emergency. Emergency exercises 2010, with a follow-up in April 2012 are conducted annually between the licensee and • WANO peer reviews at Olkiluoto NPP in 2006, STUK. Every third year all authorities are train- with a follow-up in August 2009, and in 2012 ing together at each site. • IAEA’s International Physical Protection Ad- As a result of the studies made after the visory Service (IPPAS) mission in Finland in TEPCO Fukushima Dai-ichi accident, no major 2009, with a follow-up mission in April 2012 changes are identified in the area of emergency • A Peer Review of STUK’s waste management preparedness so far. However, there is a need to related activities in 2009 (all EU member states ensure accessibility to the site in case of extreme were invited and representatives from 11 coun- weather conditions, a sufficient amount of radia- tries participated in the peer review) tion protection equipment and radiation monitor- • In 2011 STUK hosted a peer review of the ing capabilities for rescue services and communi- emergency preparedness with the OECD NEA cation capabilities. In addition, there is a need to countries ensure that the resources of rescue authorities can • STUK participated in the work carried out by be reasonably coordinated between radiological the working group of European authorities and other emergencies, should they happen simul- (European Pilot Study on Demonstrating the taneously. The coordination of activities and shar- Safety of Geological Disposal), which resulted in ing of resources between different regional rescue a recommendation for safety case content for fi- authorities also needs to be enhanced. Discussions nal disposal at different stages of final disposal. between rescue authorities, STUK and the licen- The recommendations were published in 2011. sees are ongoing. Futhermore, STUK conducted in • Finland had IRRT mission in 2001 and the 2011 a self-assement of its own response during follow-up mission in 2003. IRRS mission was the TEPCO Fukushima Dai-ichi accident. As a carried out to the regulatory body in October general result, no major deficiences were identi- 2012 and the follow-up mission is planned in fied. However, findings and experiences resulted 2015. An action plan has been prepared. in some minor modifications of STUK’s emergency • IAEA has agreed to carry out a pre-OSART plan, procedures and arrangements. (Operational Safety Review Team) mission to A close local co-operation between the regional Olkiluoto NPP unit 3 in 2013 depending on the rescue services, regional police departments, NPP project schedule with regard to fuel loading. licensees and STUK has taken place since several years. Permanent coordination groups have been Finland continues the hosting and participation in established for both Loviisa and Olkiluoto NPP’s in the international peer reviews and will report the order to ensure coordinated and consistent emer- findings of these peer reviews as well as progress of gency plans, to improve and develop emergency the action plans in the CNS report. planning and arrangements and to share lessons from the exercises, regulations and other informa- Emergency preparedness and response tion. Also extensive training is arranged by these Strengthen emergency preparedness and re- groups. In addition, a National Nuclear Power sponse Plant Emergency Preparedness Forum is needed The Finnish concept of off-site nuclear emer- in order to have co-operation and communication gency response has been developed since 1976, between permanent groups and establishment of when the first public authorities’ off-site emer- the National Forum has been agreed. The Ministry

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of the Interior and the Ministry of Social Affairs nuclear of radiological emergencies. STUK has also and Health, the regional rescue service authorities, hosted in 2009 a peer review organised by OECD/ STUK and the NPP licensees will be participating NEA on guides concerning protective measures in in the Forum. The forum will handle at least issues early and intermediate phases of a nuclear or ra- related to: diological emergency. • long term accidents of several NPP units • recovery phase actions National regulatory bodies • emergency measures outside the planning zones Strengthen the effectiveness of national regu- • scope of the emergency exercises, latory bodies • radiation monitoring capability during pro- According to the Finnish Nuclear Energy Act, longed emergency situations the overall authority in the field of nuclear energy • communication capability during prolonged is the Ministry of Employment and the Economy. emergency situations It prepares for example licensing decisions for the • availability of the emergency centres with re- Government. According to the Radiation Act, the spect to power supply, filtration of the intake air overall authority in the field of the use of radia- and the distance from the NPPs tion and other radiation practices is the Ministry • public information, information between the of Social affairs and Health. According to Section 6 authorities of the Radiation Act and Section 55 of the Nuclear • clearance of the roads, alternative transport Energy Act, STUK is responsible for the regulatory ways and means control of the safety of the use of radiation and • decontamination resources and facilities nuclear energy. The rights and responsibilities of • supply of contractor staff during the emergen- STUK are provided in the Radiation and Nuclear cies Energy Acts. • warning the population. The regulatory control of the safe use of radia- tion and nuclear energy is independently carried In addition, a transportable, insulated and heated out by STUK. No Ministry can take for its decision- container for personnel protective equipment and making a matter that has been defined by law to radiation measuring instrument is to be purchased be on the responsibility of STUK. STUK has no to quickly provide a certain amount of equipment responsibilities or duties which would be in conflict in such a case when the normal storages in the with regulatory control. NPP are unavailable e.g. due to the external haz- STUK carried out a self-assessment concern- ards or fallout. The container can be transported ing i.a. the effectiveness of the regulatory body for by a truck and it can be connected to the electricity the latest IRRS mission conducted in Finland in grid or to the movable power engine. The container October 2012. STUK identified many topics to be is estimated to be in use on 2014. further improved during the self-assessment and Further improvement of arrangements for the some additional recommendations and suggestions coordination of information to the public and me- were also given during the mission. The IRRS mis- dia during emergencies is needed to ensure that sion team found that STUK is a competent and the messages issued by different authorities are highly credible regulator and is open and transpar- consistent. Guidelines for co-operation among au- ent. It also concluded that STUK is very active in thorities have been written in a guidebook pub- promoting experience sharing both nationally and lished in November 2012. To help the implementa- internationally. Areas for further improvement to tion of guidelines seminars and workshops will be enhance overall performance of the regulatory sys- organised from the beginning of 2013. tem, included for example the following: Finland participates actively in the interna- • although STUK operates in practice as an tional co-operation also in the field of emergency independent regulatory body, the government preparedness, such as IAEA, OECD/NEA and EU/ should strengthen the legislative framework by EC (WENRA and HERCA). These working groups establishing the regulator as a body separate in discuss i.a. mutual assistance and communication, law from other arms of government co-operation and co-ordination of actions during

119 STUK-B 164 Implementation of the IAea Actn io Plan on Nuclear Safety ANNEX 6

• the government should seek to modify the Several peer reviews have been carried out at the Nuclear Energy Act so that the law clearly both Finnish NPPs during the last ten years (see and unambiguously stipulates STUK’s legal au- above the section concerning peer reviews). The li- thorities in the authorization process for safety. censees have annually sent several peers to foreing In particular, the changes should ensure that peer reviews. STUK has the legal authority to both specify According to the Finnish regulatory guides, the any licence conditions necessary for safety and licensees shall carry out a periodic safety review specify all regulations necessary for safety (PSR) at least every ten years. The Finnish PSR • Finnish legislative framework should be further process and scope are in line with the IAEA guid- developed to cover authorization for the decom- ance (NS-G-2.10). PSR is seen as a very important missioning of nuclear facilities and the final tool for promoting the continuous safety improve- closure of nuclear waste repositories ment approach. The last periodic safety reviews • STUK can further enhance the effectiveness of were finalised in Loviisa in 2007 and in Olkiluoto its inspection activities by enhancing the focus in 2009. STUK regularly updates the regulatory of inspection on the most safety-significant ar- requirements based on the operational experience eas and developing a formal qualification pro- feedback, research and technical development. gramme for inspectors. The procedure to apply new or revised regulatory guides to existing nuclear facilities is such that Based on the recommendations and suggestions an after having heard those concerned, STUK makes Action Plan has been prepared by STUK. The fol- a separate decision on how a new or revised YVL low-up mission is planned to be conducted in 2015. Guide applies to operating nuclear power plants, or to those under construction. Operating organizations Strengthen the effectiveness of operating or- IAEA safety standards ganizations with respect to nuclear safety Review and strengthen IAEA Safety Standards The responsibility for the safety rests with the and improve their implementation licensee as prescribed in the Finnish Radiation and The most important references considered in Nuclear Energy Acts. Accordingly, it is the licen- rulemaking at STUK are the IAEA safety stand- see’s obligation to assure safe use of radiation and ards, especially the Requirements-documents, and nuclear energy. Furthermore, it shall be the licen- WENRA (Western European Nuclear Regulators’ see’s obligation to assure such physical protection Association) Safety Reference Levels and Safety and emergency planning and other arrangements, Objectives for new reactors. Finnish policy is to necessary to ensure limitation of nuclear damage, participate actively in the international discus- which do not rest with the authorities. sion on developing safety standards and adopt or It is the responsibility of the regulatory body adapt the new safety requirements into national to verify that the licensees fulfill the regulations. regulations. The newly developed regulations are This verification is carried out through continuous highly in line with the most recent development oversight, safety review and assessment as well of the IAEA safety requirements. Lessons learned as inspection programmes established by STUK. from the Forsmark event in 2006 and the TEPCO In its activities, STUK emphasises the licensee’s Fukushima Dai-ichi accident in 2011 are incorpo- commitment to the strong safety culture. The ob- rated into the updated governement decrees and vious elements of licensee’s actions to meet these the new set of YVL guides to be published in 2013. responsibilities are strict adherence of regulations, prompt, timely and open actions towards the regu- International legal framework lator in unusual situations, active role in develop- Improve the effectiveness of the international ing the safety based on improvements of technol- legal framework ogy and science as well as effective exploitation of Finland signed on 20 September 1994 the experience feedback. Convention on Nuclear Safety which was adopt- The Finnish NPP licensees have regularly host- ed on 17 June 1994 in the Vienna Diplomatic ed international peer reviews (OSART, WANO). Conference. The Convention was ratified on 5

120 ANNEX 6 Implementation of the IAea Actn io Plan on Nuclear Safety STUK-B 164

January 1996, and it came into force in Finland on the Nuclear Energy Act due to the Nuclear Safety 24 October 1996. Finland has implemented the ob- Directive (Council Directive 2009/71/Euratom). In ligations of the Convention and also the objectives 2013, the Nuclear Energy Act and the Radiation of the Convention are complied with. Finland has Act are under an amendment process to imple- regularly reported and participated in the review ment the Directive 2011/70/Euratom of 19 July meetings. Finland observes the principles of the 2011 establishing a Community framework for the Convention, when applicable, also in other uses responsible and safe management of spent fuel and of nuclear energy than nuclear power plants, e.g. radioactive waste. in the use of a research reactor. Finland has par- ticipated in the working group on effectiveness and Member states planning to embark transparency of the Convention on Nuclear Safety on a nuclear power programme and is supporting the initiatives to improve the Facilitate the development of the infrastruc- CNS process. ture necessary for Member States embarking The financial provisions to cover the possible on a nuclear power programme damages to third parties caused by a nuclear ac- Providing support to embarking countries is cident have been arranged in Finland according to considered important in Finland. Finland is a the Paris and Brussels Conventions. Related to the member of the IAEA Regulatory Co-operation revision of the Paris and Brussels Conventions in Forum and has participated on the Integrated 2004, Finland has decided to enact unlimited licen- Nuclear Infrastructure Reviews (INIR) missions see’s liability by law (the Finnish Nuclear Liability organized by the IAEA. In addition, Finland par- Act). This means, that insurance coverage will be ticipates in EU/EC INIS activities by providing required for a minimum amount of EUR 700 mil- experts and training to embarking countries as lion and the liability of Finnish operators shall be well as tutoring to experts from embarking coun- unlimited in cases where nuclear damage has oc- tries. Finland has also organised and continues to curred in Finland and the third tier of the Brussels organise training courses on the experience on reg- Supplementary Convention (providing cover up ulatory oversight on new construction and project to EUR 1500 million) has been exhausted. The management, regulatory framework in Finland, revised law will also have some other modifica- and experts from embarking countries have par- tions, such as extending the claiming period up to ticipated. Experts from Finland have also lectured 30 years for victims of nuclear accidents. The law in individual IAEA training courses focused on amendment (2005) has not taken effect yet. It will embarking countries. enter into force at a later date as determined by government decree. The entering into force of the Capacity building amending act will take place as the 2004 Protocols Strengthen and maintain capacity building amending the Paris and Brussels Conventions will The competence of the licensees as well as the enter into force. vendor and main subcontractors is one of the key As the ratification of the 2004 Protocols has review areas in the licensing processes for the use been delayed, Finland made a temporary amend- of radiation and nuclear energy and during the ment in the Finnish Nuclear Liability Act in 2012, lifetime of the facilities. STUK is currently updat- implementing the provision on unlimited liability ing the legislation and regulatory guides and is go- and requirement of insurance coverage for a mini- ing to set goals and requirements on the resources mum amount of EUR 700 million. The temporary needed to be available for the licensee during nor- law came into force in January 2012 and will be mal operation as well as during emergencies. repealed when the 2005 law amendment takes ef- The management of STUK highlights the need fect. In Finland, the finishing off the international for competent workforce. STUK has adopted a com- ratification process of the convention amendments petence management system and nuclear safety without any undue delay is considered to be ex- and regulatory competencies are also emphasised tremely important. in STUK’s strategy. Implementation of the strategy Finland is a Member State of the European is reflected into the annual training programmes, Union. In 2011 some amendments were done in on the job training and new recruitments.

121 STUK-B 164 Implementation of the IAea Actn io Plan on Nuclear Safety ANNEX 6

The national nuclear safety and waste manage- of a nuclear or radiological emergency, for various ment research programmes have an important role types of emergencies (such as fallout from nuclear in the competence building of all essential organi- detonation, severe accident in a NPP, malicious sations involved in nuclear energy. These research acts, contamination due to radioactive substances programmes have two roles: for the first ensuring etc.). VAL Guides contain reference levels of expo- the availability of experts and for the second en- sure during the first year and factors, other than suring the on-line transfer of the research results radiation, affecting choice of protective measures to the organisations participating to the steering of and protective measures to be considered during the programmes and fostering the expertise. STUK nuclear or radio-logical emergencies and transi- has an important role in the steering of these pro- tion to recovery. VAL Guides contain criteria when grammes. protective measures are needed and when those There is a basic professional training course on can be lifted or modified. Criteria are given for nuclear safety organised together with the Finnish each countermeasure as a projected dose and as an organisations in the field. The first 6-week course operational intervention level. They also include commenced in September 2003 and the 11th basic triggers such as plant condition, or emergency ac- professional training course will commence in au- tion levels such as duration of a protective meas- tumn 2013. At the moment, about 500 newcomers ure. VAL Guides include principles for reducing and junior experts, of whom about 80 have been exposure of various parts of society (e.g. actions from STUK, have participated in these courses. concerning population, exercising own profession The content and structure of the course has been in a contaminated area, decontamination, handling enhanced according to the feedback received from of waste containing radioactive substances etc). the participants. VAL Guides are to be put into force by the Ministry Due to planned expansion of the use of nuclear of the Interior. energy in Finland, a comprehensive study has been In Finland, there is an automatic external conducted in Finland to explore the need of ex- dose rate monitoring network consisting of about perts and education of experts in Finland to meet 250 stations throughout the country. Results are the needs from the organizations in the field. The available in real time (every 10th minute). In ad- study was completed in March 2012. dition, a network has 22 stations with spectrom- (http://www.tem.fi/files/33402/Report_of_the_ eters situated around the Finnish NPPs and in Committee_for_Nuclear_Energy_Competence_in_ Helsinki. Nuclear power plants have trained moni- Finland.pdf) toring teams capable of making dose rate and air concentration measurements. STUK has trained Protection of people and the monitoring teams for dose rate monitoring, mobile environment from ionizing radiation spectrometers and a laboratory vehicle which has Ensure the on-going protection of people and state of the art monitoring equipment for gamma the environment from ionizing radiation fol- (HPGe), alpha and air sampler. Results can be ob- lowing a nuclear emergency tained in 30 second interval. During nuclear or radiological incidents and There is also a network of environment and emergencies STUK is responsible for safety assess- foodstuffs laboratories which have the capability ment of radiation situation and recommendations to measure gamma radioactivity levels in the food and advice for protective measures as defined in and environmental samples. STUK coordinates the Rescue Act. STUK provides recommendations operation and provides technical support if needed. of protective measures to authorities on local, In addition, STUK has delivered regional hospitals provincial and governmental level. Furthermore, monitoring equipment for monitoring iodine in STUK provides advice to private sector for trade thyroid. This measuring capability is meant for and commerce. screening the public for contamination of iodine. STUK has prepared so called VAL Guides, In addition to actual emergency rescue plan- which contain the intervention strategy in Finland. ning, roles and responsibilities of authorities for VAL Guides contain protective measures and in- longer-term actions following a nuclear accident tervention levels in early and intermediate phases have been defined. Longer-term actions include

122 ANNEX 6 Implementation of the IAea Actn io Plan on Nuclear Safety STUK-B 164 e.g. decontamination of environment, management consistent. Guidelines for co-operation among au- of waste containing radioactive substances, radia- thorities have been written in a guidebook pub- tion monitoring and surveys, health control of the lished by the Ministry of Interior in November population, measures concerning agricultural and 2012. To help the implementation of guidelines other production and measures to ensure uncon- seminars and workshops are organised from the taminated food and feeding stuffs. beginning of 2013. Even more general principles and guidance of coordination or public communica- Communication and information tion during emergencies are given in the guidance dissemination by prime ministers office. This guideance will be Enhance transparency and effectiveness of updated during 2013. communication and improve dissemination of In an accident situation the principal informa- information tion route of warnings to the public is FM radio, The Decree on STUK defines STUK’s tasks. TV and internet. The first outdoor warning to the One of the tasks is to inform about radiation and public close the NPP is given by general warning nuclear safety matters and participate on training signal via sirens or loudspeakers. By arrange- activities in the area. STUK utilises many means ment with broadcasting companies, urgent RDS- to communicate with public and interested stake- notifications can be transmitted promptly over the holders, such as meetings, seminars, and training FM-radio and TV. There is a new specific law for courses. All these are tailored and targeted to dif- warning messages via radio and TV. Law is enter- feren stakeholders and stakeholder groups. ing into force on 1st June 2013. STUK puts special interest in internet to in- Finland has several bilateral agreements for form public and interested stakeholders about exchange of information on nuclear facilities and nuclear and radiation safety in general, risks re- on notification of a nuclear and radiation emer- lated to radiation and use of nuclear energy, safety gency, e.g. with Sweden, Norway, Russia, Ukraine, requirements, roles and responsibilities of STUK, Denmark and Germany. In addition, STUK has STUK’s organization, current activities and oper- done bilateral arrangements with several foreign ating experience, significant regulatory decisions regulatory bodies, which cover generally exchange taken, events and publications and safety research. of information on safety regulations, operational STUK web pages can be found (www.stuk.fi) in experiences, waste management etc. Such an ar- Finnish, Swedish and in English. STUK has also rangement have been made with NRC (USA), ASN made itself available in social media (facebook and (France), FANR (United Arab Emirates), NSSC twitter). and KINS (Republic of Korea), TAEK (Turkey), What comes to radiation emergencies and haz- ENSI (Switzerland), SUJB (Czech Republic), ards, according to the Rescue Act and the Decree of Rostechnadzor (Russian Federation), and CNSC the Ministry of the Interior concerning informing (Canada). public during nuclear or radiological emergencies, the authority in charge is responsible for informing Research and development public on protective measures and other activities Effectively utilize research and development to be carried out. Authorities at governmental, pro- The Nuclear Energy Act was amended in 2003 vincial, and municipal level provide information on to ensure funding for a long term nuclear safe- their own activities and give instructions regard- ty and nuclear waste management research in ing their own sphere of responsibility. In case of Finland. Money is collected annually from the li- a nuclear power plant accident there are many cence holders to a special fund. Regarding nuclear organisations providing information. Thus special safety research the amount of money is propor- attention needs to be paid to coordination of timing tional to the actual thermal power of the licensed and content. power plants or the thermal power presented in Further improvement of arrangements for the the Decision-in-Principle. For the nuclear waste coordination of information to the public and me- research, the annual funding payments are propor- dia during emergencies is needed to ensure that tional to the current fund holdings for the future the messages issued by different authorities are waste management activities.

123 STUK-B 164 Implementation of the IAea Actn io Plan on Nuclear Safety ANNEX 6

The research projects are selected so that they been allocated to the research of external events. support and develop the competences in nuclear The objective of KYT2014 (Finnish Research safety and to create preparedness for the regula- programme on Nuclear Waste Management) is to tor to be able to respond on emerging and urgent ensure the sufficient and comprehensive availabil- safety issues. These national safety research pro- ity of the nuclear technological expertise and other grammes are called SAFIR and KYT. The key capabilities required by the authorities when com- topics of the recent nuclear safety research pro- paring different nuclear waste management ways gramme (SAFIR2014) are organisation and human and implementation methods. KYT2014 is divided factors, automation and control room, fuel and re- into three main categories: actor physics, thermal hydraulics, severe accidents, • new and alternative technologies in nuclear structural safety of reactor circuit, construction waste management safety, probabilistic safety analysis and develop- • safety research in nuclear waste management ment of research infrastructure. The amount of • social science studies related to nuclear waste money collected from the licensees in year 2012 management was about 5.6 million € for nuclear safety research. and the main emphasis is on safety related re- The research projects have also additional fund- search. The programme is conducted during 2011– ing from other sources. The total volume of the 2014 and the total funding is 2.8 M€, of which programme in 2012 was 10 million €. The results State Nuclear Waste Management Fund (VYR) of the research programme are public. More infor- covers 1.7 M€. mation on the planning, steering and the research In Finland, the Technical Research Centre of reports of the SAFIR and KYT programmes are Finland (VTT) is the largest research organisa- available on the puclic websites (http://safir2014. tion in the field of nuclear energy. At VTT, about vtt.fi/ and http://kyt2014.vtt.fi/). 200 experts are working in the field of nuclear In 2011, research needs originating from the energy, half of them full-time. The total volume TEPCO Fukushima Dai-ichi accident were stud- of the nuclear energy research in the year 2012 ied, and an appendix addressing the topics for was about 75 million € (estimate of the Ministry further research (e.g. spent fuel pool accidents) was of Employment and the Economy). This figure added to the research programme. The ongoing includes research related to use of nuclear energy SAFIR2014 research programme already included made in all the stakerholder organisations. Two research projects on extreme weather phenomena, thirds of the research is focused on the final dis- extreme seawater level variations and seismic posal of spent fuel. The largest individual organiza- issues. As a result of the TEPCO Fukushima Dai- tions are VTT, GTK (Geological Survey of Finland), ichi accident, a reassessment was made how the LUT (Lappeenranta University of Technology) and accident should be taken into account, and the Aalto University (former Helsinki University of research projects were somewhat redirected. The Technology, HUT). research programme was supplemented with re- Finland also participates in international re- search topics related to natural hazards and multi- search activities, such as OECD/NEA/CSNI work- ple failure events, the adequacy and scope of nucle- ing groups, consortium which builds a research ar power plant design basis, mitigating the impact reactor in France, scandinavian NKS research of accidents (e.g. high concentration of boron in the programme, EU programmes, and bilateral co- reactor circuit, hydrogen formation and transport, operation with several countries. The Finnish tec- range of fission products released in core melt), and nical support organisations are active parties of the overall life cycle of nuclear fuel including spent TSO organisations co-operation such as ETSON in fuel pools. Some additional resources have also Europe and IAEA TSO Forum.

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