Finnish report on nuclear safety : Finnish 9th national report as referred to in Article 5 of the Convention on Nuclear Safety
Säteilyturvakeskus
08.08.2022
Julkaisun pysyvä osoite on
https://urn.fi/URN:ISBN:978-952-309-540-3
STUK-B : 288
https://urn.fi/URN:ISBN:978-952-309-540-3
STUK-B : 288
Tiivistelmä
Executive summary
Finland signed the Convention on Nuclear Safety on 20 September 1994 and it 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 combined Eighth and Ninth Review Meeting in March/April 2023.
There are two operating nuclear power plants in Finland: the Loviisa and Olkiluoto plants. The Loviisa plant comprises of two PWR units (pressurised water reactors of VVER type), operated by Fortum Power and Heat Oy (Fortum). Olkiluoto plant, operated by Teollisuuden Voima Oyj (TVO), has two BWR units (boiling water reactors) and one new PWR (EPR) unit under nuclear commissioning. At both sites there are interim storages for spent fuel as well as final disposal facilities for low and intermediate level nuclear wastes. Posiva, a joint company of Fortum and TVO, is constructing a spent nuclear fuel encapsulation plant and disposal facility at Olkiluoto site. Posiva applied operating license for them in December 2021. Posiva or its facilities are not comprehensively discussed in this report, as matters related to spent fuel management are reported in the frame of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management.
A new NPP unit, Fennovoima Hanhikivi unit 1 (VVER type design in Pyhäjoki) was under construction licence application review until spring 2022. In April 2022 Fennovoima terminated the Engineering, Procurement and Construction- type plant delivery contract with plant vendor RAOS Project Oy. Fennovoima send subsequently construction license application withdrawal request to the Ministry of Economic Affairs and Employment of Finland (MEAE). MEAE presented expiration of Fennovoima construction license application handling to the government in June 2022. Since the Fennovoima Hanhikivi 1 review was well underway while drafting this report, Hanhikivi unit 1 is discussed in this report, mainly with regard to the licensing process, organisational matters and siting (see Articles 7, 10, 11 and 17 and Annex 5).
Furthermore, VTT Technical Research Centre of Finland Ltd (VTT) has operated a Triga Mark II research reactor, FiR 1, in Espoo. The reactor is in decommissioning phase; it was permanently shut down in 2015 and the spent fuel has been removed from the site.
In this report, the 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 publishing the Eighth National report are as follows: Initiating an overall renewal of nuclear safety legislation, first fuel loading and first criticality and following commissioning and test operation of Olkiluoto unit 3, granting license to FiR research reactor decommissioning and the subsequent decommissioning activities including removal of spent fuel from the site, review of Loviisa NPP PSR results (STUK’s decision in April 2022), submittal of a licence renewal application for Loviisa 1 and 2 units for additional 20 years of operation and the withdrawl of the construction license application of Fennovoima’s Hanhikivi 1 unit. Latest development in the various topics of the Convention on Nuclear Safety is described in the relevant articles.
All the Fukushima Dai-ichi-related safety improvements presented in the Finnish national action plan have been implemented. Last actions were completed in 2020. Further information related to the actions taken in Finland following the accident at the Fukushima Dai-ichi nuclear power plant are described in more detail under Articles 16, 17, 18, 19 and Annexes 2, 3 and 4.
Finland continues to host and to participate in the international peer reviews. The following missions have been performed or are planned for the period of 2019–2023:
• Olkiluoto 1&2 OSART mission. The mission was conducted in 2017 with a follow-up in 2019.
• Pre-Operational OSART mission for Olkiluoto 3 in March 2018.
• Loviisa NPP OSART mission. The mission took place in March 2018, with a follow-up in 2020.
• WANO follow-up review at Loviisa NPP in 2019 with a follow-up in 2021. Next WANO peer review and the corporate peer review are scheduled to 2023.
• WANO peer review at Olkiluoto NPP in 2020. Next WANO peer review and the corporate peer review are scheduled to 2023.
• WANO Olkiluoto 3 pre-startup Peer Review in 2019 with a follow-up in 2020.
• IPPAS mission will be performed in 2022.
• ARTEMIS mission will take place in 2022.
• IRRS mission will take place in 2022.
• EPREV mission is planned for 2023-2024.
• Second European Topical Peer Review will start with self-assessment phase in 2022, the topic will be fire safety.
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, to take into account updates in international requirements, e.g. the Council Directive 2014/87/Euratom amending Directive 2009/71/Euratom, the amendment (2014/52/EU) of Directive 2011/92/EU, and the radiation safety directive (2013/59/Euratom). No deviation from the Convention obligations has been identified in the Finnish regulatory infrastructure including nuclear and radiation safety regulations.
• Due to the aforementioned updates of the legislation, and due the fact that since the renewal of YVL Guides in 2013 nearly all IAEA Safety Requirements have been revised, and updated WENRA reference levels have been published, STUK started to update the YVL Guides in 2017. The update was completed in 2021. The revised guides are applied as such for new nuclear facilities. Separate facility specific implementation decisions are made for the existing facilities and facilities under construction. Regular update and implementation of regulatory guides, particularly with regard to nuclear power plants in operation, are unique measures in the international perspective.
• STUK published its current strategy in 2018 covering the period of 2018–2022. The strategy includes goals for STUK’s own performance (e.g. ability to understand complex entities, flexible and efficient working methods) as well as for the oversight (more risk-informed and commensurable oversight, emphasizing the responsibility of the operators) and societal aspects (the society is resilient to disturbances, people understand the risks of radiation). The implementation of the strategy is underway, and implementation of the strategic goals related to the oversight will continue in the new strategic period. An overall renewal of regulations and regulatory guides to support the strategic goals is an example of longer-term activity. From 2022, a more continuous development of strategy is applied.
• An overall renewal of nuclear safety legislation has been initiated by the Ministry of the Economic Affairs and Employment. STUK regulations and guides will be renewed as well. The objective is to renew and clarify the legislation which has been modified several times over the decades. At the same time this is an opportunity to clarify the structure according to the principles laid down in the Finnish Constitution. Another objective in the overall renewal of STUK regulations and guides is to support the development of oversight to be more risk-informed and emphasizing the responsibility of the operators according to STUK’s strategic goals. Also new technologies including SMRs (Small Modular Reactors) will be taken into account in the renewal work.
• The licensees have shown good safety performance in carrying out their safety related responsibilities in the operation and modernisation of existing NPPs. During recent years, only minor operational events (INES 1 and below) were reported, and no major safety problems have occurred.
• Safety assessment is a continuous process and living full scope levels 1 and 2 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 2015–2017 and in 2020–2022, and the periodic safety review of the Olkiluoto plant was carried out in 2016–2018 in the connection of the operating license renewal. Several plant modifications have been carried out at the operating NPPs during the recent years to further improve the safety. Some of these modifications are originating from the Fukushima Dai-ichi accident lessons learnt.
• The resources of STUK have been increased to meet the needs to oversee the construction of the new nuclear facilities in Finland. VTT supports effectively STUK in the safety assessment work by performing safety analyses and providing safety analysis capabilities and tools. The national research programmes SAFIR (Finnish Research Programme on Nuclear Power Plant Safety) and KYT (Finnish Research Programme on Nuclear Waste Management) develop and maintain the competencies in nuclear safety and waste management to enable STUK to take measures in unexpected events at Finnish plants or elsewhere, and to support decision making for the benefits of society and the environment. According to the changes in Nuclear Energy Act the research programmes above will be combined in a new programme SAFER2028 starting in the beginning of 2023. STUK has actively participated with the licencees and the research organisations in planning of the new framework programme to ensure balanced implementation of the research needs covered in the existing programmes. External peer review (made by international team of experts) on the effectiveneness and efficiency of national safety research programmes was conducted in early 2022, https://julkaisut.valtioneuvosto.fi/handle/10024/164066.
Challenges identified by the Seventh Review Meeting
The Seventh Review Meeting in 2017 identified some challenges and suggestions to improve nuclear safety in Finland. These issues are included and addressed in this report. The issues were as follows:
• To manage simultaneously the oversight of many on-going activities in different life-cycle phases of nuclear facilities. This is a situation that STUK has never dealt with before.
• Provisions for plant ageing; I&C and other system modernisations carried out at the existing NPPs (incl. safety improvements); ageing management programmes are in place and re-reviewed in PSRs;
• Commissioning of Olkiluoto unit 3, review of the operating licence application, commissioning tests, and start of operation;
• Regulatory review of construction license application of Hanhikivi unit 1;
• Decommissioning of the FiR 1 research reactor.
• To finalise STUK strategic communication plan for raising public awareness and knowledge in risks related to radiation and nuclear energy.
Concerning the first challenge, the mentioned oversight activities are discussed specially in the context of Articles 14 and 19 and in Appendices 4 and 5. The review of the Olkiluoto 3 operating license application, as well as the review of the FiR license application for decommissioning have been successfully completed. On the other hand, the review of the CL application of Hanhikivi-1 has been canceled because of withdrawal request from Fennovoima and subsequent government decision on expiration of CL application. Concerning ageing management, STUK completed the assessment of the periodic safety review of Olkiluoto 1&2 in 2018 and of Loviisa NPP in April 2022. Finland also participated in the Topical Peer Review on the ageing management under the Nuclear Safety Directive 2014/87/EURATOM, completed in 2017, and updated its National Action Plan in 2021. As the main oversight tasks are known well in advance, STUK is able to consider them in resource planning and knowledge management and in the use of technical support organisations. STUK’s resources and the amount of oversight are discussed in more detail in Article 8.
Interest in nuclear power in Finland is increasing, due to on-going new-build projects and public debate about future prospects of SMRs (Small Modular Reactors). With this in mind, communication and information sharing with media and the general public on nuclear and radiation safety has become an increasingly important success factor for STUK, relevant ministries and utilities. Regulatory processes and decisions have to be clear and understandable by the general public. Risks related to radiation should be communicated realistically. Due to this challenge, STUK has carried out a number of development measures to improve its strategic communications and the use of modern communication tools. In particular, STUK has focused on the communication capacity of its personnel. STUK applies the principle that all STUK’s employees have both the right and duty to communicate with public and the media concerning their own area of expertise. For example, STUK’s personnel is encouraged to represent STUK in the social media. STUK has also developed key messages to communicate radiation and nuclear risks and continued to develop its crisis communication capabilities. Furthermore, STUK has defined strategic goals for communication, and measures – not only the outputs but particularly the outcomes – how communication changes opinions, attitudes and change of behaviour.
In addition, in the Seventh Review Meeting, some common major issues were identified based on the Country Group discussions. It was recommended that these issues are taken into account when preparing the national reports. Out of these issues, ageing management and safety culture were chosen to be discussed in the Eigth Review Meeting.
The nine common major issues are listed below with reference to the Articles (in brackets) in which the issues are addressed. Summaries related to ageing management and safety culture are given below, more detailed discussion can be found in Articles 14 (ageing management) and 10 (safety culture).
• Safety culture (Article 10)
• International peer reviews (Annex 6)
• Legal framework and independence of regulatory body (Article 7, Article 8)
• Financial and human resources (Article 8, Article 11)
• Knowledge management (Article 8, Article 11)
• Supply chain (Article 13, Article 14)
• Managing of safety of ageing nuclear facilities and plant life extensions (Article 14)
• Emergency preparedness (Article 16)
• Stakeholder consultation & communication (Article 7, Article 8, Annex 6).
Ageing management
STUK published new Guide YVL A.8 dedicated to ageing management in 2013. Prior to this, the requirements for ageing management were covered by several different guides. In the guide, some new requirements were introduced, mainly concerning the scope and content of the ageing management program, annual reporting and management of spare parts for long-lasting accidents. The latest version was published in February 2019. The implementation of the updated ageing management requirements is underway at the utilities. Some challenges in complying with the new requirements have been encountered. For example, inspections performed after publishing the new guide in 2013 revealed that the amount of spare parts can be inadequate for keeping the plant in a safe state also during prolonged transients and accidents, and that some of the spare parts in the storage have either aged or became obsolete. Another challenge had to do with knowledge and resources allocated for ensuring appropriate ageing management programme at NPPs. An additional challenge is to conduct relevant research to both educate personnel and to identify new ageing mechanisms in order to develop new inspection or monitoring technologies for detecting degradation early enough. During recent years significant progress has taken place in the spare part management. Organisational arrangements have been made and a dedicated database (Proactive Obsolescence Management System) has been introduced at both Loviisa and Olkiluoto NPPs. Dedicated groups consisting of members representing necessary disciplines such as maintenance, quality control and procurement have taken charge of spare parts in terms of necessary availability and conditions.
A generic lesson learned is that the closer the nuclear power plants come to the end of their licensed operation, the more challenging it is for the licensees to initiate modernisations or other major activities to improve the safety of the NPPs, especially if the market price of electricity is low. Instead of renewing a system or a component, modernisation may be rejected, or a partial modification is carried out that may result in ageing issues for the remaining parts. Finland has successfully applied periodic safety reviews (PSR) for operating NPPs. The practice has been that the licensee is obliged to demonstrate that the safety of the operations can be ensured and improved also during the next 10 years. In order to do that the licensee has to commit to making safety improvements including necessary major modernisations to address the ageing of structures, systems and components (SSC).
An expert group dedicated to ageing management has been established in STUK to oversee how the licensees perform their duties in the ageing management of SSCs. The group, consisting of mechanical, electrical, I&C, civil structure, and radiation safety experts as well as resident inspectors, plans and coordinates STUK’s regulatory duties pertaining to the ageing of nuclear facility systems, equipment and structures. If any shortcomings are found, for example in the condition monitoring or maintenance, the group contacts the licensee for clarifications or corrective actions. The group also follows up findings from other countries and evaluates their possible relevance for the ageing management of the Finnish nuclear power plants.
Finland participated in the Topical Peer Review (TPR) “Ageing Management” under the Nuclear Safety Directive 2014/87/EURATOM, carried out in 2017–18. The overall conclusion was that the ageing management has been satisfactory. However, some challenges and areas for improvement, as well as good practices, were identified and Finland established a national action plan to address the findings. The results of the TPR are discussed under Article 14.
Safety Culture
The STUK Regulation sets a binding requirement for the licensees to maintain a good safety culture where safety is the priority. STUK revised the Guide YVL A.3 setting requirements for leadership and management for safety based on the IAEA GSR Part 2.
STUK carries out safety culture oversight by collecting and analysing observations from resident inspectors, documents, events and from other interactions with the licensee. STUK has implemented a tool for recording the observations. In order to gain a more systemic view on the licensee safety performance STUK has modified its internal meeting structures. The interactions between technical and organizational factors experts have been intensified to ensure timely and risk informed understanding of the licensee performance. STUK also conducts specific inspections focusing on Leadership and Safety culture. STUK also follows the licensees’ safety culture self-assessments (e.g. results, possible changes in the methodology, actions decided based on the results). Furthermore, STUK has utilised VTT to carry out independent safety culture assessments in the licensee organisations. Recent independent safety culture assessment was done at Loviisa (2021). An independent safety culture assessment of the Hanhikivi 1 main designer was conducted in 2019 and the assessment of the plant supplier RAOS project and the main contractor Titan 2 was completed in spring 2022.
The utilities employ several different means for maintaining good safety culture. Priority of safety is emphasised in the safety or company policies. In addition to high level policy, the licensees have safety culture programmes, road maps or development plans for implementing the measures for maintaining good safety culture. The licensees monitor the safety culture by regular surveys and in-depth assessments. They also have in their organisations groups or functions independent of the line organisation to oversee and discuss safety and safety culture matters. Corrective action groups or functions exist. Training – including safety culture topics – is given to all newcomers and usually also to contractors. The safety significant contractors are required to familiarise their workforce with safety culture principles which is one of the topics of licensees’s audits on contractors and suppliers.
However, some organizational issues that challenge the good safety culture have been identified at the licensee or license applicant organisations. Similarly, some previous challenges have been resolved. TVO has successfully improved its work climate, staffing levels and personnel motivation having a positive impact on the safety culture in general. Fennovoima’s management system and the organisational structure has undergone significant changes first in 2019 and again in 2021. Fennovoima has improved the openness and orderliness of handling of safety matters, including of concerns that personnel may raise. The impacts of schedule pressures of the project are one of the subjects that STUK pays attention to in its oversight. During the periodic safety assessment of Loviisa nuclear power plants licensee has pointed out improvement needs in e.g. safety leadership, clarity of procedures and instructions and sufficient consideration of human and organisational factors in various contexts. Also, STUK has in its oversight emphasised that Fortum’s leadership shall improve the understanding of the organisational root causes of e.g. events, and enhance the leadership response to deviations and follow up of the development actions to ensure their implementation and effectiveness.
At STUK, safety and safety culture are emphasized in the Management System. In 2013, all departments made a self-assessment of their safety culture. The results were used in updating STUK’s safety and quality policy. In 2016 a safety culture survey was performed and in 2018 development of STUK’s Safety culture program was started on the basis of the assessment results. The program was further developed based on the key findings from the Country-Specific Safety Culture Forum (in 2019) and fully launched in 2020. In 2021 STUK’s safety culture was considered to be at a good level. For example, safety is considered to be a true value in STUK’s organization and different groups and individuals in STUK bear the responsibility for safety. However, areas for further enhancement of STUK’s safety culture were identified (e.g. need for further development of internal interaction to for instance enable healthy questioning atmosphere at STUK as well as the manageability of work through for instance prioritization – in terms of occasionally experienced hurry at work).
To better understand the ingrained conventions in the Finnish culture and their possible positive and/or negative impacts on safety culture, Finland has continued to explore the national cultural and societal factors influencing leadership and safety culture via the Finnish nuclear community within the Finnish nuclear research program SAFIR 2022. Furthermore, in 2019 STUK participated in the collaborative effort of Country-Specific Safety Culture Forum with OECD NEA and WANO. The Finnish nuclear utilities and STUK reflected upon the country specific culture traits and their possible influences on the nuclear safety culture. A report was published by the NEA in 2019, https://www.oecd-nea.org/jcms/pl_15146/country-specific-safety-culture-forum-finland.
Challenges and good practices identified by Finland
Finland has identified the following challenges:
• To ensure resources for the implementation of STUK’s strategic objective related to the implementation of more risk-informed and performance-based regulation and oversight, and highlighting licensee’s responsibility for safety, including
• Changes needed in the nuclear safety regulations and regulatory guides, e.g. to be more be goal setting and enabling (also for emerging technologies, e.g. SMRs) and emphasising the licensees’ responsibility for safety.
• Developing the oversight activities to be more risk-informed and performance-based and emphasising licensees’ responsibility, e.g. by crediting licensees’ own oversight activities.
• Development of oversight practices and tools to take into account the possibilities offered by digitalisation and ensuring that the personnel has the necessary related skills.
• Ensuring resources on the implementation of the strategic objectives and overall renewal of legislation together with the oversight of many ongoing activities in different life-cycle phases of nuclear facilities.
• The reguirements in STUK’s regulatory guides (YVL-guides) are quite detailed in some respects limiting licensees to use design solutions that would meet the safety objectives of mandatory legislation but do not fullfil the explicit requirement of the regulatory guidance. Licensees have also indicated that it prevents licensees to find suppliers to provide systems, structures and components needed for plant modifications and maintenance. One key objective in the overall renewal of STUK regulations and guides is to support the development of oversight to be more risk-informed, goal-oriented and emphasizing the responsibility of the operators according to STUK’s strategic goals to set detailed requirements to fullfil mandatory safety objectives for instance. Also new technologies including SMRs (Small Modular Reactors) will be taken into account in the renewal work. The issue has also been addressed in KELPO project (please see section on good practices).
• Long-term operation of the NPPs, including retention and renewal of the necessary competence.
• Ageing management should be proactive and consider also technological obsolescence. Early preparations (design, contracts, qualification, licensing) are advisable. The closer the nuclear power plants come to the end of their licensed operation, the more challenging it is for the licensees to initiate modernisations or other major activities to improve the safety of the NPPs, especially if the market price of electricity is low.
• Knowledge and resources allocated for ensuring appropriate ageing management programme at NPPs must be maintained.
• Additional challenge is to conduct relevant research to both educate personnel and to identify possible new ageing mechanisms and to develop new inspection or monitoring technologies for early enough detection of degradation.
• While new advanced inspection methods may reveal defects that have not been able to recognise with earlier technology, identification of the associated root or progress of the defects over time is challenging.
Finland considers the following to be a good practice or a good performance:
• Improving culture for safety: Finnish nuclear community, including the regulator, has taken various actions to understand and improve culture for safety in their organisations. These include research activities in the Finnish nuclear research program SAFIR 2018 (e.g. the sociological factors influencing safety culture in the Finnish nuclear community), licensees and licence applicant’s safety culture programmes complemented by independent safety culture studies conducted by VTT, STUK’s studies on its own safety culture programme and development of a safety culture programme for further improvement, and organising a Country-Specific Safety Culture Forum in Helsinki where participants from the Finnish nuclear utilities and STUK discussed the country specific culture traits and their possible influences on the nuclear safety culture. (good practice)
• Finnish licensees carried out a project (KELPO) to pilot the use of industrial standard components in safety classified applications. STUK has also participated in the project as an observer giving its views on the subject. As a result of the project, licensees have defined common processes and tools for the procurement and regulatory approval of the standard components that also meet STUK’s expectations for nuclear and radiation safety. (good practice)
• Requirement management at STUK: STUK has developed a systematic approach for regulatory requirement management. The requirement management database contains the requirements set in the regulations and guides. In the tool, each requirement has attributes: links to higher level legislation, links to licensing phase like construction or operation in which the requirement is relevant etc. Furthermore, the information on the fulfilment of the requirements at the facilities and the approved exemptions are recorded in the tool. This enables STUK to have all the time an overall picture of the compliance with the requirements at the NPPs. In updating the regulations and guides, the justification for modifications as well as comments received from the stakeholders are recorded in the tool. Between updates, the identified needs for modifications are also entered into the tool. STUK will also use the tool for overall renewal of nuclear safety legislation, which enables following how the existing requirements are implemented in the new regulatory framework and ensures efficient maintenance of the structure and hierarchy of the requirements. (good practice)
• Interpretation and implementation of the Vienna Declaration in the Finnish Regulations: The Finnish Nuclear Energy Decree stipulates that the radioactive releases resulting from a severe accident at a nuclear power plant shall not necessitate large-scale protective measures for the population nor any long-term restrictions on the use of extensive areas of land and water. This safety goal is similar to the first principle of the Vienna Declaration. In addition, the Decree states that in order to limit the long-term effects, the limit for atmospheric releases of Cs-137 is 100 TBq. The possibility of exceeding the set limit and of a release in the early stages of an accident requiring measures to protect the population shall be extremely small. STUK has included in the regulatory guides more detailed and more concrete interpretations for those safety goals of the Vienna Declaration. Guide YVL C.3 explains what is meant by “large-scale protective measures”. Analyses must be provided to demonstrate that any release of radioactive substances in a severe accident shall not warrant the evacuation of the population beyond the protective zone (appr. 5 km) or the need for people beyond the emergency planning zone (appr. 20 km) to seek shelter indoors. Guide YVL A.7 states that a nuclear power plant unit shall be designed in a way that:
• the mean value of the frequency of a release of radioactive substances from the plant during an accident involving a Cs-137 release into the atmosphere in excess of 100 TBq is less than 5·10–7/year;
• the accident sequences, in which the containment function fails or is lost in the early phase of a severe accident, have only a small contribution to the reactor core damage frequency. (good practice)
• Radiation measurement team from volunteers: A large scale nuclear or radiological emergency like a severe accident at a nuclear power plant, an explosion of a nuclear weapon or an explosion of so-called dirty bomb could threat the function of the society. STUK, The National Defense Training Association of Finland and National Emergency Supply Agency launched in 2017 a project to establish a radiation measurement team from volunteers. The persons are trained and equipped by the three above mentioned organizations. The purpose of the team is to support authorities during a large scale nuclear or radiological emergency. In such situations, STUK’s duty is to give recommendations to the domestic authorities. The recommendations are based, among other things, on the performed radiation measurements. The first training course for the volunteers was arranged in spring 2018, followed by another course in autumn of the same year. Regular training courses have been organized since 2018. The team is to consist of about 40 persons and it is assumed to start radiation measurements during the intermediate phase of radiation or nuclear emergency. (good practice)
• The national nuclear safety research programme SAFIR: SAFIR is a comprehensive nuclear safety research programme, where all relevant stakeholders are participating. It is a significant resource investment for a small country to ensure and develop national nuclear safety assessment capabilities and competencies. The results of the research projects in SAFIR are publicly available and can be used freely. All the results are reported in English, which enables using the results also outside Finland. These practices are being implemented in the new research programme combining SAFIR and the KYT, and further enhancing the mutual research needs identified in both these programmes. External peer review (made by international team of experts) on the effectiveneness and efficiency of national safety research programmes was conducted in early 2022. (good performance)
• Communication with the public and the media: STUK applies the principle that all STUK’s employees have both the right and duty to participate in communication with the public and the media concerning their areas of expertise. STUK, for example, encourages its personnel to represent themselves as experts and STUK in social media. STUK has focused on communication capacity of its personnel and has published guidelines for the principles and practices of communication. Furthermore, STUK has defined strategic goals for communication, and measures – not only the outputs but particularly the outcomes – how communication changes opinions, attitudes and change of behaviour. (good performance)
Consideration of the Vienna Declaration on Nuclear Safety
The Vienna Declaration on Nuclear Safety was adopted by the Contracting Parties by consensus at the Diplomatic Conference on 9 February 2015. The Vienna Declaration contains three principles to guide the Contracting Parties.
The first principle concerning the safety goal for new nuclear power plant design, siting, construction and operation is included in the Finnish regulations (see Articles 17 and 18). Furthermore, the Nuclear Energy Decree stipulates that the radioactive releases resulting from a severe accident at a nuclear power plant shall not necessitate large-scale protective measures for the population nor any long-term restrictions on the use of extensive areas of land and water. In order to limit the long term effects, the limit for atmospheric releases of Cs-137 is 100 TBq. The possibility of exceeding the set limit and of a release in the early stages of an accident requiring measures to protect the population shall be extremely small. Also, the possibility of a release in the early stages of the accident requiring measures to protect the public shall be extremely small. Finnish regulatory Guide YVL C.3 explains in more detail what is meant by “large-scale protective measures”. Analyses must be provided to demonstrate that any release of radioactive substances in a severe accident shall not warrant the evacuation of the population beyond the protective zone (appr. 5 km) or the need for people beyond the emergency planning zone (appr. 20 km) to seek shelter indoors. Guide YVL A.7 states that a nuclear power plant unit shall be designed in compliance with the Government Decree principles in a way that:
• the mean value of the frequency of a release of radioactive substances from the plant during an accident involving a Cs-137 release into the atmosphere in excess of 100 TBq is less than 5·10–7/year;
• the accident sequences, in which the containment function fails or is lost in the early phase of a severe accident, have only a small contribution to the reactor core damage frequency.
Regarding the second principle, on the implementation of safety improvements at the operating NPPs to meet, as far as reasonably practicable, the safety goal of the first principle, Finnish Nuclear energy Act states that a periodic safety review (PSR) shall be conducted at least every ten years. In addition, it states that safety shall be maintained as high as practically possible and for further development of safety, measures shall be implemented that can be considered justified considering operating experience and safety research and advances in science and technology. Hence, the implementation of safety improvements has been a continuing process at both the Finnish NPPs since their commissioning. Especially the approach that STUK issues regulatory guides for new NPPs and regularly updates them, and then makes separate decision on the implementation and needed safety improvements at the operating nuclear facilities and facilities under construction, ensures reasonably practicable safety improvements at the Finnish nuclear facilities. Finnish regulations require also that licensees maintain an up-to-date and comprehensive plant-specific probabilistic risk assessment (PRA) and that they use the PRA to enhance nuclear facility safety, to identify and prioritise plant modification needs and to compare the safety significance of alternative solutions. The most significant plant modifications and modernisation projects carried out at the Finnish NPPs during the plant lifetime including backfitting of severe accident management systems during 1980’s and 1990’s are described in Annexes 2 and 3.
Regarding the third principle of the Vienna Declaration requiring that national regulations need to take into account the relevant IAEA safety standards and, as appropriate, other good practices, the Finnish nuclear safety regulations and guides are regularly updated taking into account operating and construction experience, safety research and advances in science and technology. The overall revision of the regulatory guides in end of 2013 took into account the international guidance (e.g. the IAEA safety standards and the WENRA safety reference levels) and the lessons learnt from the Fukushima Dai-ichi accident. Due to updates in the IAEA Safety Requirements and in the WENRA Reference Levels since then, STUK started to update the YVL Guides anew in 2017. The update was completed in 2021.
Management of the Covid-19 situation in Finland
Measures adopted by nuclear facility licensees
On March 6, 2020 STUK requested information from the licensees of the operating power plants on how they are prepared to possible worsening of the pandemic situation (still an epidemic situation at the time of the request). The licensees’ answers were received on March 13 and March 17 from TVO (operator of the Olkiluoto NPP) and Fortum (operator of the Loviisa NPP), respectively. The licensees had identified critical functions/positions and listed the minimum number of the critical staff in different groups. During the pandemics, there has not been any difficulties in fulfilling these requirements.
Finnish nuclear research reactor was closed down permanently in June 2015. In the beginning the core loading was changed so that the reactor was sub-critical in all situations, later on the core was defueled and fuel has been removed from the site and country. Therefore, the reactor doesn’t require any active control or cooling systems. Operational personnel is not required to be present at reactor all the time and licensee, VTT, has evaluated the adequacy of operational and security personnel.
Other nuclear installations include operational nuclear waste disposal facilities that do not require active operations for safety. Current operational disposal facilities are at nuclear power plant sites and operated by nuclear power plant organisations (TVO and Fortum).
The licensees have followed the development of the situation and the suggestions and guidance from the Finnish Government and health authorities closely and further instructed their own staff and suppliers on expectations of practices when entering the plant and the licensees’ premises, as well as on suggestions on the actions during free time. The licensees’ instructions have been somewhat stricter than those given generally to the public in Finland, and this was the case already in the early phases of the situation. The actions include:
• restricting the number of people in the same room
• minimising access to areas important to safety and operation
• requirements for protective measures (masks, testing, …)
• supporting the remote work for those that the nature of the duties allows this
• restrictions on travelling both abroad and in Finland
• setting up company rules on temporary quarantines in early phases of the situation for those that have been travelling abroad (also for persons coming from Uusimaa region in Finland to the Olkiluoto site)
• checking that the people accessing the plants have not been in contact with patients diagnosed with COVID-19 infection or come from abroad since the previous two weeks.
The licensees formed specific groups within their organizations that follow the development of the pandemic situation continuously in order to quickly react to the changes and respond accordingly. Special measures to avoid spreading of a corona virus epidemic among the NPP staff and especially among the control room staff have been taken already from the early warnings of the virus. These measures have been tightened gradually with the changes in the national policies of the authorities.
Refuelling outages have been under evaluation, and the availability and need of external personnel and supplies has been discussed with the licensees regularly. Annual fuel exchange and short maintenance period at Olkiluoto NPP were scheduled for spring/summer 2020, and these arrangements were re-evaluated in respect with the pandemic situation. Olkiluoto unit 2 outage was carried out as planned in May 2020 (only a refueling outage with the duration of 8 days). The planned outage of Olkiluoto unit 1 was supposed to be 25 days but it was shortened to 14 days due to action to restrict possible spreading of corona in the plant personnel. The pressure test of Olkiluoto unit 1 reactor pressure vessel (RPV) required by STUK in the decision on periodic safety review in 2018 was postponed by 1 year. Postponing of the pressure test of the RPV was accepted by STUK. Also, other changes to the Olkiluoto unit 1 outage were reviewed and accepted by STUK, but there was no need for deviations, but rather changes to the implementation schedules. In Loviisa NPP, the outages were carried out as planned both in 2020 and 2021.
Measures adopted by the Radiation and Nuclear Safety Authority STUK
STUK has been in a continuous direct contact with the licensees. Most of the government employees were working remotely for two years since mid-March 2020 with the exception of resident inspectors at the site. Concerning the radiation and nuclear safety oversight, STUK has organised its regulatory functions so that most activities can continue normally also in remote mode. This includes document reviews, decision making, meetings with licensees, developing regulations, etc. On-site inspections continued in most safety significant topics at the operating NPPs (Loviisa units 1 and 2 and Olkiluoto 1 and 2) and at the Olkiluoto 3 unit under commissioning where there were no alternative options available. Objective was to minimise the travel needs and also the risk of spreading the coronavirus to the site. Manufacturing inspections done abroad were interrupted due to travel restrictions and instead inspections will be conducted later at the nuclear power plant sites in Finland. STUK has resident inspectors at the NPP sites and objective has been to use mainly them for on-site inspections but if needed, it has been possible to send also additional inspectors from the headquarters (case-by-case decision).
Information security matters have been taken into account also in remote communications by choosing appropriate channels and methods corresponding to the classification of information being transmitted. Remote inspections have been done in areas where it has been possible using conferencing software taking into account the information security restrictions.
During the early phases of the pandemic, STUK raised its licensees awareness of organisational factors in pandemic situation. Pandemic situation affects licensee organisations and may cause many cumulative changes into human performance and related risks, e.g.:
• Temporary guidance (how to ensure that everybody has time to read them and make sure what are currently valid guidance, …)
• Changes to plant modification/ projects implementation and schedules (dependencies needs to be taken into account, formal documentation, up-to-dateness of the plans and guidance, …) – e.g. outages were shortened and some plant modifications/ tests were postponed by one year
• Lack of personnel (deputies with less experience might be used, …)
• Decision making (many decisions due to many changes, overall picture of the effects of the decisions, is there enough time to do multidisciplinary decisions and discussion about risks, …)
• Information flow (less face-to-face meetings, possible misunderstandings and complications in telemeetings, …)
• Mental loading (situation can be more stressfull for some people and can affect the work performance, …).
The conclusion was that even when the staffing of control room personnel and other critical personnel groups will be ensured, situation needed special attention from the organizational factors point of view. Rapid changes in routines, work processes and plans are most common factors behind events and accidents (experience from history). But in the end, there were not any significant findings made in the oversight related to organisational factors.
STUK made also plans for ensuring its internal and external communication activities and particularly its emergency response capabilities. STUK for instance followed sickness rates of its staff to be able to react if needed. During the pandemics, there has not been any challenges identified and sickness rates have been even lower compared to the previous years. STUK also conducted a tabletop exercise on simultaneous radiation emergency and restrictions to see how pandemic restrictions could impact not only operations of emergency organisations but also STUK’s recommendations and decisions.
STUK’s environmental radiation monitoring functions have been continued normally (sampling, measurements and laboratory functions).
One of the lessons learnt from the pandemic situation is that organisations need to be prepared for different kind of hazards. There can’t be separate plans for every detail and certain resiliency is always a strength of the organisation. Typically, business continuity plans (BCP) concentrate mainly on cyber threats or physical hazards that are limited in time. So, one area for improvement is to widen the scope of BCPs both at the licensees and regulatory body for cases like prolonged pandemic. Risk management is also typically an area for improvement, and it should also identify the main risks which need to be prepared by BCP.
In conclusion, Finland has implemented the obligations of the Convention and also the objectives of the Convention, including the principles of the Vienna Declaration on Nuclear Safety are complied with. Safety improvements have been implemented at the Loviisa and Olkiluoto plants since their commissioning. Legislation and regulatory guidance have been further developed. 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, domestic and international operating experience, safety research results, and development of science and technology. Second IRRS mission (the IAEA’s Integrated Regulatory Review Team) in Finaland will be carried out in October 2022. No urgent need exists for additional improvements to upgrade the safety of the Finnish nuclear power plants in the context of the Convention.
Finland signed the Convention on Nuclear Safety on 20 September 1994 and it 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 combined Eighth and Ninth Review Meeting in March/April 2023.
There are two operating nuclear power plants in Finland: the Loviisa and Olkiluoto plants. The Loviisa plant comprises of two PWR units (pressurised water reactors of VVER type), operated by Fortum Power and Heat Oy (Fortum). Olkiluoto plant, operated by Teollisuuden Voima Oyj (TVO), has two BWR units (boiling water reactors) and one new PWR (EPR) unit under nuclear commissioning. At both sites there are interim storages for spent fuel as well as final disposal facilities for low and intermediate level nuclear wastes. Posiva, a joint company of Fortum and TVO, is constructing a spent nuclear fuel encapsulation plant and disposal facility at Olkiluoto site. Posiva applied operating license for them in December 2021. Posiva or its facilities are not comprehensively discussed in this report, as matters related to spent fuel management are reported in the frame of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management.
A new NPP unit, Fennovoima Hanhikivi unit 1 (VVER type design in Pyhäjoki) was under construction licence application review until spring 2022. In April 2022 Fennovoima terminated the Engineering, Procurement and Construction- type plant delivery contract with plant vendor RAOS Project Oy. Fennovoima send subsequently construction license application withdrawal request to the Ministry of Economic Affairs and Employment of Finland (MEAE). MEAE presented expiration of Fennovoima construction license application handling to the government in June 2022. Since the Fennovoima Hanhikivi 1 review was well underway while drafting this report, Hanhikivi unit 1 is discussed in this report, mainly with regard to the licensing process, organisational matters and siting (see Articles 7, 10, 11 and 17 and Annex 5).
Furthermore, VTT Technical Research Centre of Finland Ltd (VTT) has operated a Triga Mark II research reactor, FiR 1, in Espoo. The reactor is in decommissioning phase; it was permanently shut down in 2015 and the spent fuel has been removed from the site.
In this report, the 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 publishing the Eighth National report are as follows: Initiating an overall renewal of nuclear safety legislation, first fuel loading and first criticality and following commissioning and test operation of Olkiluoto unit 3, granting license to FiR research reactor decommissioning and the subsequent decommissioning activities including removal of spent fuel from the site, review of Loviisa NPP PSR results (STUK’s decision in April 2022), submittal of a licence renewal application for Loviisa 1 and 2 units for additional 20 years of operation and the withdrawl of the construction license application of Fennovoima’s Hanhikivi 1 unit. Latest development in the various topics of the Convention on Nuclear Safety is described in the relevant articles.
All the Fukushima Dai-ichi-related safety improvements presented in the Finnish national action plan have been implemented. Last actions were completed in 2020. Further information related to the actions taken in Finland following the accident at the Fukushima Dai-ichi nuclear power plant are described in more detail under Articles 16, 17, 18, 19 and Annexes 2, 3 and 4.
Finland continues to host and to participate in the international peer reviews. The following missions have been performed or are planned for the period of 2019–2023:
• Olkiluoto 1&2 OSART mission. The mission was conducted in 2017 with a follow-up in 2019.
• Pre-Operational OSART mission for Olkiluoto 3 in March 2018.
• Loviisa NPP OSART mission. The mission took place in March 2018, with a follow-up in 2020.
• WANO follow-up review at Loviisa NPP in 2019 with a follow-up in 2021. Next WANO peer review and the corporate peer review are scheduled to 2023.
• WANO peer review at Olkiluoto NPP in 2020. Next WANO peer review and the corporate peer review are scheduled to 2023.
• WANO Olkiluoto 3 pre-startup Peer Review in 2019 with a follow-up in 2020.
• IPPAS mission will be performed in 2022.
• ARTEMIS mission will take place in 2022.
• IRRS mission will take place in 2022.
• EPREV mission is planned for 2023-2024.
• Second European Topical Peer Review will start with self-assessment phase in 2022, the topic will be fire safety.
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, to take into account updates in international requirements, e.g. the Council Directive 2014/87/Euratom amending Directive 2009/71/Euratom, the amendment (2014/52/EU) of Directive 2011/92/EU, and the radiation safety directive (2013/59/Euratom). No deviation from the Convention obligations has been identified in the Finnish regulatory infrastructure including nuclear and radiation safety regulations.
• Due to the aforementioned updates of the legislation, and due the fact that since the renewal of YVL Guides in 2013 nearly all IAEA Safety Requirements have been revised, and updated WENRA reference levels have been published, STUK started to update the YVL Guides in 2017. The update was completed in 2021. The revised guides are applied as such for new nuclear facilities. Separate facility specific implementation decisions are made for the existing facilities and facilities under construction. Regular update and implementation of regulatory guides, particularly with regard to nuclear power plants in operation, are unique measures in the international perspective.
• STUK published its current strategy in 2018 covering the period of 2018–2022. The strategy includes goals for STUK’s own performance (e.g. ability to understand complex entities, flexible and efficient working methods) as well as for the oversight (more risk-informed and commensurable oversight, emphasizing the responsibility of the operators) and societal aspects (the society is resilient to disturbances, people understand the risks of radiation). The implementation of the strategy is underway, and implementation of the strategic goals related to the oversight will continue in the new strategic period. An overall renewal of regulations and regulatory guides to support the strategic goals is an example of longer-term activity. From 2022, a more continuous development of strategy is applied.
• An overall renewal of nuclear safety legislation has been initiated by the Ministry of the Economic Affairs and Employment. STUK regulations and guides will be renewed as well. The objective is to renew and clarify the legislation which has been modified several times over the decades. At the same time this is an opportunity to clarify the structure according to the principles laid down in the Finnish Constitution. Another objective in the overall renewal of STUK regulations and guides is to support the development of oversight to be more risk-informed and emphasizing the responsibility of the operators according to STUK’s strategic goals. Also new technologies including SMRs (Small Modular Reactors) will be taken into account in the renewal work.
• The licensees have shown good safety performance in carrying out their safety related responsibilities in the operation and modernisation of existing NPPs. During recent years, only minor operational events (INES 1 and below) were reported, and no major safety problems have occurred.
• Safety assessment is a continuous process and living full scope levels 1 and 2 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 2015–2017 and in 2020–2022, and the periodic safety review of the Olkiluoto plant was carried out in 2016–2018 in the connection of the operating license renewal. Several plant modifications have been carried out at the operating NPPs during the recent years to further improve the safety. Some of these modifications are originating from the Fukushima Dai-ichi accident lessons learnt.
• The resources of STUK have been increased to meet the needs to oversee the construction of the new nuclear facilities in Finland. VTT supports effectively STUK in the safety assessment work by performing safety analyses and providing safety analysis capabilities and tools. The national research programmes SAFIR (Finnish Research Programme on Nuclear Power Plant Safety) and KYT (Finnish Research Programme on Nuclear Waste Management) develop and maintain the competencies in nuclear safety and waste management to enable STUK to take measures in unexpected events at Finnish plants or elsewhere, and to support decision making for the benefits of society and the environment. According to the changes in Nuclear Energy Act the research programmes above will be combined in a new programme SAFER2028 starting in the beginning of 2023. STUK has actively participated with the licencees and the research organisations in planning of the new framework programme to ensure balanced implementation of the research needs covered in the existing programmes. External peer review (made by international team of experts) on the effectiveneness and efficiency of national safety research programmes was conducted in early 2022, https://julkaisut.valtioneuvosto.fi/handle/10024/164066.
Challenges identified by the Seventh Review Meeting
The Seventh Review Meeting in 2017 identified some challenges and suggestions to improve nuclear safety in Finland. These issues are included and addressed in this report. The issues were as follows:
• To manage simultaneously the oversight of many on-going activities in different life-cycle phases of nuclear facilities. This is a situation that STUK has never dealt with before.
• Provisions for plant ageing; I&C and other system modernisations carried out at the existing NPPs (incl. safety improvements); ageing management programmes are in place and re-reviewed in PSRs;
• Commissioning of Olkiluoto unit 3, review of the operating licence application, commissioning tests, and start of operation;
• Regulatory review of construction license application of Hanhikivi unit 1;
• Decommissioning of the FiR 1 research reactor.
• To finalise STUK strategic communication plan for raising public awareness and knowledge in risks related to radiation and nuclear energy.
Concerning the first challenge, the mentioned oversight activities are discussed specially in the context of Articles 14 and 19 and in Appendices 4 and 5. The review of the Olkiluoto 3 operating license application, as well as the review of the FiR license application for decommissioning have been successfully completed. On the other hand, the review of the CL application of Hanhikivi-1 has been canceled because of withdrawal request from Fennovoima and subsequent government decision on expiration of CL application. Concerning ageing management, STUK completed the assessment of the periodic safety review of Olkiluoto 1&2 in 2018 and of Loviisa NPP in April 2022. Finland also participated in the Topical Peer Review on the ageing management under the Nuclear Safety Directive 2014/87/EURATOM, completed in 2017, and updated its National Action Plan in 2021. As the main oversight tasks are known well in advance, STUK is able to consider them in resource planning and knowledge management and in the use of technical support organisations. STUK’s resources and the amount of oversight are discussed in more detail in Article 8.
Interest in nuclear power in Finland is increasing, due to on-going new-build projects and public debate about future prospects of SMRs (Small Modular Reactors). With this in mind, communication and information sharing with media and the general public on nuclear and radiation safety has become an increasingly important success factor for STUK, relevant ministries and utilities. Regulatory processes and decisions have to be clear and understandable by the general public. Risks related to radiation should be communicated realistically. Due to this challenge, STUK has carried out a number of development measures to improve its strategic communications and the use of modern communication tools. In particular, STUK has focused on the communication capacity of its personnel. STUK applies the principle that all STUK’s employees have both the right and duty to communicate with public and the media concerning their own area of expertise. For example, STUK’s personnel is encouraged to represent STUK in the social media. STUK has also developed key messages to communicate radiation and nuclear risks and continued to develop its crisis communication capabilities. Furthermore, STUK has defined strategic goals for communication, and measures – not only the outputs but particularly the outcomes – how communication changes opinions, attitudes and change of behaviour.
In addition, in the Seventh Review Meeting, some common major issues were identified based on the Country Group discussions. It was recommended that these issues are taken into account when preparing the national reports. Out of these issues, ageing management and safety culture were chosen to be discussed in the Eigth Review Meeting.
The nine common major issues are listed below with reference to the Articles (in brackets) in which the issues are addressed. Summaries related to ageing management and safety culture are given below, more detailed discussion can be found in Articles 14 (ageing management) and 10 (safety culture).
• Safety culture (Article 10)
• International peer reviews (Annex 6)
• Legal framework and independence of regulatory body (Article 7, Article 8)
• Financial and human resources (Article 8, Article 11)
• Knowledge management (Article 8, Article 11)
• Supply chain (Article 13, Article 14)
• Managing of safety of ageing nuclear facilities and plant life extensions (Article 14)
• Emergency preparedness (Article 16)
• Stakeholder consultation & communication (Article 7, Article 8, Annex 6).
Ageing management
STUK published new Guide YVL A.8 dedicated to ageing management in 2013. Prior to this, the requirements for ageing management were covered by several different guides. In the guide, some new requirements were introduced, mainly concerning the scope and content of the ageing management program, annual reporting and management of spare parts for long-lasting accidents. The latest version was published in February 2019. The implementation of the updated ageing management requirements is underway at the utilities. Some challenges in complying with the new requirements have been encountered. For example, inspections performed after publishing the new guide in 2013 revealed that the amount of spare parts can be inadequate for keeping the plant in a safe state also during prolonged transients and accidents, and that some of the spare parts in the storage have either aged or became obsolete. Another challenge had to do with knowledge and resources allocated for ensuring appropriate ageing management programme at NPPs. An additional challenge is to conduct relevant research to both educate personnel and to identify new ageing mechanisms in order to develop new inspection or monitoring technologies for detecting degradation early enough. During recent years significant progress has taken place in the spare part management. Organisational arrangements have been made and a dedicated database (Proactive Obsolescence Management System) has been introduced at both Loviisa and Olkiluoto NPPs. Dedicated groups consisting of members representing necessary disciplines such as maintenance, quality control and procurement have taken charge of spare parts in terms of necessary availability and conditions.
A generic lesson learned is that the closer the nuclear power plants come to the end of their licensed operation, the more challenging it is for the licensees to initiate modernisations or other major activities to improve the safety of the NPPs, especially if the market price of electricity is low. Instead of renewing a system or a component, modernisation may be rejected, or a partial modification is carried out that may result in ageing issues for the remaining parts. Finland has successfully applied periodic safety reviews (PSR) for operating NPPs. The practice has been that the licensee is obliged to demonstrate that the safety of the operations can be ensured and improved also during the next 10 years. In order to do that the licensee has to commit to making safety improvements including necessary major modernisations to address the ageing of structures, systems and components (SSC).
An expert group dedicated to ageing management has been established in STUK to oversee how the licensees perform their duties in the ageing management of SSCs. The group, consisting of mechanical, electrical, I&C, civil structure, and radiation safety experts as well as resident inspectors, plans and coordinates STUK’s regulatory duties pertaining to the ageing of nuclear facility systems, equipment and structures. If any shortcomings are found, for example in the condition monitoring or maintenance, the group contacts the licensee for clarifications or corrective actions. The group also follows up findings from other countries and evaluates their possible relevance for the ageing management of the Finnish nuclear power plants.
Finland participated in the Topical Peer Review (TPR) “Ageing Management” under the Nuclear Safety Directive 2014/87/EURATOM, carried out in 2017–18. The overall conclusion was that the ageing management has been satisfactory. However, some challenges and areas for improvement, as well as good practices, were identified and Finland established a national action plan to address the findings. The results of the TPR are discussed under Article 14.
Safety Culture
The STUK Regulation sets a binding requirement for the licensees to maintain a good safety culture where safety is the priority. STUK revised the Guide YVL A.3 setting requirements for leadership and management for safety based on the IAEA GSR Part 2.
STUK carries out safety culture oversight by collecting and analysing observations from resident inspectors, documents, events and from other interactions with the licensee. STUK has implemented a tool for recording the observations. In order to gain a more systemic view on the licensee safety performance STUK has modified its internal meeting structures. The interactions between technical and organizational factors experts have been intensified to ensure timely and risk informed understanding of the licensee performance. STUK also conducts specific inspections focusing on Leadership and Safety culture. STUK also follows the licensees’ safety culture self-assessments (e.g. results, possible changes in the methodology, actions decided based on the results). Furthermore, STUK has utilised VTT to carry out independent safety culture assessments in the licensee organisations. Recent independent safety culture assessment was done at Loviisa (2021). An independent safety culture assessment of the Hanhikivi 1 main designer was conducted in 2019 and the assessment of the plant supplier RAOS project and the main contractor Titan 2 was completed in spring 2022.
The utilities employ several different means for maintaining good safety culture. Priority of safety is emphasised in the safety or company policies. In addition to high level policy, the licensees have safety culture programmes, road maps or development plans for implementing the measures for maintaining good safety culture. The licensees monitor the safety culture by regular surveys and in-depth assessments. They also have in their organisations groups or functions independent of the line organisation to oversee and discuss safety and safety culture matters. Corrective action groups or functions exist. Training – including safety culture topics – is given to all newcomers and usually also to contractors. The safety significant contractors are required to familiarise their workforce with safety culture principles which is one of the topics of licensees’s audits on contractors and suppliers.
However, some organizational issues that challenge the good safety culture have been identified at the licensee or license applicant organisations. Similarly, some previous challenges have been resolved. TVO has successfully improved its work climate, staffing levels and personnel motivation having a positive impact on the safety culture in general. Fennovoima’s management system and the organisational structure has undergone significant changes first in 2019 and again in 2021. Fennovoima has improved the openness and orderliness of handling of safety matters, including of concerns that personnel may raise. The impacts of schedule pressures of the project are one of the subjects that STUK pays attention to in its oversight. During the periodic safety assessment of Loviisa nuclear power plants licensee has pointed out improvement needs in e.g. safety leadership, clarity of procedures and instructions and sufficient consideration of human and organisational factors in various contexts. Also, STUK has in its oversight emphasised that Fortum’s leadership shall improve the understanding of the organisational root causes of e.g. events, and enhance the leadership response to deviations and follow up of the development actions to ensure their implementation and effectiveness.
At STUK, safety and safety culture are emphasized in the Management System. In 2013, all departments made a self-assessment of their safety culture. The results were used in updating STUK’s safety and quality policy. In 2016 a safety culture survey was performed and in 2018 development of STUK’s Safety culture program was started on the basis of the assessment results. The program was further developed based on the key findings from the Country-Specific Safety Culture Forum (in 2019) and fully launched in 2020. In 2021 STUK’s safety culture was considered to be at a good level. For example, safety is considered to be a true value in STUK’s organization and different groups and individuals in STUK bear the responsibility for safety. However, areas for further enhancement of STUK’s safety culture were identified (e.g. need for further development of internal interaction to for instance enable healthy questioning atmosphere at STUK as well as the manageability of work through for instance prioritization – in terms of occasionally experienced hurry at work).
To better understand the ingrained conventions in the Finnish culture and their possible positive and/or negative impacts on safety culture, Finland has continued to explore the national cultural and societal factors influencing leadership and safety culture via the Finnish nuclear community within the Finnish nuclear research program SAFIR 2022. Furthermore, in 2019 STUK participated in the collaborative effort of Country-Specific Safety Culture Forum with OECD NEA and WANO. The Finnish nuclear utilities and STUK reflected upon the country specific culture traits and their possible influences on the nuclear safety culture. A report was published by the NEA in 2019, https://www.oecd-nea.org/jcms/pl_15146/country-specific-safety-culture-forum-finland.
Challenges and good practices identified by Finland
Finland has identified the following challenges:
• To ensure resources for the implementation of STUK’s strategic objective related to the implementation of more risk-informed and performance-based regulation and oversight, and highlighting licensee’s responsibility for safety, including
• Changes needed in the nuclear safety regulations and regulatory guides, e.g. to be more be goal setting and enabling (also for emerging technologies, e.g. SMRs) and emphasising the licensees’ responsibility for safety.
• Developing the oversight activities to be more risk-informed and performance-based and emphasising licensees’ responsibility, e.g. by crediting licensees’ own oversight activities.
• Development of oversight practices and tools to take into account the possibilities offered by digitalisation and ensuring that the personnel has the necessary related skills.
• Ensuring resources on the implementation of the strategic objectives and overall renewal of legislation together with the oversight of many ongoing activities in different life-cycle phases of nuclear facilities.
• The reguirements in STUK’s regulatory guides (YVL-guides) are quite detailed in some respects limiting licensees to use design solutions that would meet the safety objectives of mandatory legislation but do not fullfil the explicit requirement of the regulatory guidance. Licensees have also indicated that it prevents licensees to find suppliers to provide systems, structures and components needed for plant modifications and maintenance. One key objective in the overall renewal of STUK regulations and guides is to support the development of oversight to be more risk-informed, goal-oriented and emphasizing the responsibility of the operators according to STUK’s strategic goals to set detailed requirements to fullfil mandatory safety objectives for instance. Also new technologies including SMRs (Small Modular Reactors) will be taken into account in the renewal work. The issue has also been addressed in KELPO project (please see section on good practices).
• Long-term operation of the NPPs, including retention and renewal of the necessary competence.
• Ageing management should be proactive and consider also technological obsolescence. Early preparations (design, contracts, qualification, licensing) are advisable. The closer the nuclear power plants come to the end of their licensed operation, the more challenging it is for the licensees to initiate modernisations or other major activities to improve the safety of the NPPs, especially if the market price of electricity is low.
• Knowledge and resources allocated for ensuring appropriate ageing management programme at NPPs must be maintained.
• Additional challenge is to conduct relevant research to both educate personnel and to identify possible new ageing mechanisms and to develop new inspection or monitoring technologies for early enough detection of degradation.
• While new advanced inspection methods may reveal defects that have not been able to recognise with earlier technology, identification of the associated root or progress of the defects over time is challenging.
Finland considers the following to be a good practice or a good performance:
• Improving culture for safety: Finnish nuclear community, including the regulator, has taken various actions to understand and improve culture for safety in their organisations. These include research activities in the Finnish nuclear research program SAFIR 2018 (e.g. the sociological factors influencing safety culture in the Finnish nuclear community), licensees and licence applicant’s safety culture programmes complemented by independent safety culture studies conducted by VTT, STUK’s studies on its own safety culture programme and development of a safety culture programme for further improvement, and organising a Country-Specific Safety Culture Forum in Helsinki where participants from the Finnish nuclear utilities and STUK discussed the country specific culture traits and their possible influences on the nuclear safety culture. (good practice)
• Finnish licensees carried out a project (KELPO) to pilot the use of industrial standard components in safety classified applications. STUK has also participated in the project as an observer giving its views on the subject. As a result of the project, licensees have defined common processes and tools for the procurement and regulatory approval of the standard components that also meet STUK’s expectations for nuclear and radiation safety. (good practice)
• Requirement management at STUK: STUK has developed a systematic approach for regulatory requirement management. The requirement management database contains the requirements set in the regulations and guides. In the tool, each requirement has attributes: links to higher level legislation, links to licensing phase like construction or operation in which the requirement is relevant etc. Furthermore, the information on the fulfilment of the requirements at the facilities and the approved exemptions are recorded in the tool. This enables STUK to have all the time an overall picture of the compliance with the requirements at the NPPs. In updating the regulations and guides, the justification for modifications as well as comments received from the stakeholders are recorded in the tool. Between updates, the identified needs for modifications are also entered into the tool. STUK will also use the tool for overall renewal of nuclear safety legislation, which enables following how the existing requirements are implemented in the new regulatory framework and ensures efficient maintenance of the structure and hierarchy of the requirements. (good practice)
• Interpretation and implementation of the Vienna Declaration in the Finnish Regulations: The Finnish Nuclear Energy Decree stipulates that the radioactive releases resulting from a severe accident at a nuclear power plant shall not necessitate large-scale protective measures for the population nor any long-term restrictions on the use of extensive areas of land and water. This safety goal is similar to the first principle of the Vienna Declaration. In addition, the Decree states that in order to limit the long-term effects, the limit for atmospheric releases of Cs-137 is 100 TBq. The possibility of exceeding the set limit and of a release in the early stages of an accident requiring measures to protect the population shall be extremely small. STUK has included in the regulatory guides more detailed and more concrete interpretations for those safety goals of the Vienna Declaration. Guide YVL C.3 explains what is meant by “large-scale protective measures”. Analyses must be provided to demonstrate that any release of radioactive substances in a severe accident shall not warrant the evacuation of the population beyond the protective zone (appr. 5 km) or the need for people beyond the emergency planning zone (appr. 20 km) to seek shelter indoors. Guide YVL A.7 states that a nuclear power plant unit shall be designed in a way that:
• the mean value of the frequency of a release of radioactive substances from the plant during an accident involving a Cs-137 release into the atmosphere in excess of 100 TBq is less than 5·10–7/year;
• the accident sequences, in which the containment function fails or is lost in the early phase of a severe accident, have only a small contribution to the reactor core damage frequency. (good practice)
• Radiation measurement team from volunteers: A large scale nuclear or radiological emergency like a severe accident at a nuclear power plant, an explosion of a nuclear weapon or an explosion of so-called dirty bomb could threat the function of the society. STUK, The National Defense Training Association of Finland and National Emergency Supply Agency launched in 2017 a project to establish a radiation measurement team from volunteers. The persons are trained and equipped by the three above mentioned organizations. The purpose of the team is to support authorities during a large scale nuclear or radiological emergency. In such situations, STUK’s duty is to give recommendations to the domestic authorities. The recommendations are based, among other things, on the performed radiation measurements. The first training course for the volunteers was arranged in spring 2018, followed by another course in autumn of the same year. Regular training courses have been organized since 2018. The team is to consist of about 40 persons and it is assumed to start radiation measurements during the intermediate phase of radiation or nuclear emergency. (good practice)
• The national nuclear safety research programme SAFIR: SAFIR is a comprehensive nuclear safety research programme, where all relevant stakeholders are participating. It is a significant resource investment for a small country to ensure and develop national nuclear safety assessment capabilities and competencies. The results of the research projects in SAFIR are publicly available and can be used freely. All the results are reported in English, which enables using the results also outside Finland. These practices are being implemented in the new research programme combining SAFIR and the KYT, and further enhancing the mutual research needs identified in both these programmes. External peer review (made by international team of experts) on the effectiveneness and efficiency of national safety research programmes was conducted in early 2022. (good performance)
• Communication with the public and the media: STUK applies the principle that all STUK’s employees have both the right and duty to participate in communication with the public and the media concerning their areas of expertise. STUK, for example, encourages its personnel to represent themselves as experts and STUK in social media. STUK has focused on communication capacity of its personnel and has published guidelines for the principles and practices of communication. Furthermore, STUK has defined strategic goals for communication, and measures – not only the outputs but particularly the outcomes – how communication changes opinions, attitudes and change of behaviour. (good performance)
Consideration of the Vienna Declaration on Nuclear Safety
The Vienna Declaration on Nuclear Safety was adopted by the Contracting Parties by consensus at the Diplomatic Conference on 9 February 2015. The Vienna Declaration contains three principles to guide the Contracting Parties.
The first principle concerning the safety goal for new nuclear power plant design, siting, construction and operation is included in the Finnish regulations (see Articles 17 and 18). Furthermore, the Nuclear Energy Decree stipulates that the radioactive releases resulting from a severe accident at a nuclear power plant shall not necessitate large-scale protective measures for the population nor any long-term restrictions on the use of extensive areas of land and water. In order to limit the long term effects, the limit for atmospheric releases of Cs-137 is 100 TBq. The possibility of exceeding the set limit and of a release in the early stages of an accident requiring measures to protect the population shall be extremely small. Also, the possibility of a release in the early stages of the accident requiring measures to protect the public shall be extremely small. Finnish regulatory Guide YVL C.3 explains in more detail what is meant by “large-scale protective measures”. Analyses must be provided to demonstrate that any release of radioactive substances in a severe accident shall not warrant the evacuation of the population beyond the protective zone (appr. 5 km) or the need for people beyond the emergency planning zone (appr. 20 km) to seek shelter indoors. Guide YVL A.7 states that a nuclear power plant unit shall be designed in compliance with the Government Decree principles in a way that:
• the mean value of the frequency of a release of radioactive substances from the plant during an accident involving a Cs-137 release into the atmosphere in excess of 100 TBq is less than 5·10–7/year;
• the accident sequences, in which the containment function fails or is lost in the early phase of a severe accident, have only a small contribution to the reactor core damage frequency.
Regarding the second principle, on the implementation of safety improvements at the operating NPPs to meet, as far as reasonably practicable, the safety goal of the first principle, Finnish Nuclear energy Act states that a periodic safety review (PSR) shall be conducted at least every ten years. In addition, it states that safety shall be maintained as high as practically possible and for further development of safety, measures shall be implemented that can be considered justified considering operating experience and safety research and advances in science and technology. Hence, the implementation of safety improvements has been a continuing process at both the Finnish NPPs since their commissioning. Especially the approach that STUK issues regulatory guides for new NPPs and regularly updates them, and then makes separate decision on the implementation and needed safety improvements at the operating nuclear facilities and facilities under construction, ensures reasonably practicable safety improvements at the Finnish nuclear facilities. Finnish regulations require also that licensees maintain an up-to-date and comprehensive plant-specific probabilistic risk assessment (PRA) and that they use the PRA to enhance nuclear facility safety, to identify and prioritise plant modification needs and to compare the safety significance of alternative solutions. The most significant plant modifications and modernisation projects carried out at the Finnish NPPs during the plant lifetime including backfitting of severe accident management systems during 1980’s and 1990’s are described in Annexes 2 and 3.
Regarding the third principle of the Vienna Declaration requiring that national regulations need to take into account the relevant IAEA safety standards and, as appropriate, other good practices, the Finnish nuclear safety regulations and guides are regularly updated taking into account operating and construction experience, safety research and advances in science and technology. The overall revision of the regulatory guides in end of 2013 took into account the international guidance (e.g. the IAEA safety standards and the WENRA safety reference levels) and the lessons learnt from the Fukushima Dai-ichi accident. Due to updates in the IAEA Safety Requirements and in the WENRA Reference Levels since then, STUK started to update the YVL Guides anew in 2017. The update was completed in 2021.
Management of the Covid-19 situation in Finland
Measures adopted by nuclear facility licensees
On March 6, 2020 STUK requested information from the licensees of the operating power plants on how they are prepared to possible worsening of the pandemic situation (still an epidemic situation at the time of the request). The licensees’ answers were received on March 13 and March 17 from TVO (operator of the Olkiluoto NPP) and Fortum (operator of the Loviisa NPP), respectively. The licensees had identified critical functions/positions and listed the minimum number of the critical staff in different groups. During the pandemics, there has not been any difficulties in fulfilling these requirements.
Finnish nuclear research reactor was closed down permanently in June 2015. In the beginning the core loading was changed so that the reactor was sub-critical in all situations, later on the core was defueled and fuel has been removed from the site and country. Therefore, the reactor doesn’t require any active control or cooling systems. Operational personnel is not required to be present at reactor all the time and licensee, VTT, has evaluated the adequacy of operational and security personnel.
Other nuclear installations include operational nuclear waste disposal facilities that do not require active operations for safety. Current operational disposal facilities are at nuclear power plant sites and operated by nuclear power plant organisations (TVO and Fortum).
The licensees have followed the development of the situation and the suggestions and guidance from the Finnish Government and health authorities closely and further instructed their own staff and suppliers on expectations of practices when entering the plant and the licensees’ premises, as well as on suggestions on the actions during free time. The licensees’ instructions have been somewhat stricter than those given generally to the public in Finland, and this was the case already in the early phases of the situation. The actions include:
• restricting the number of people in the same room
• minimising access to areas important to safety and operation
• requirements for protective measures (masks, testing, …)
• supporting the remote work for those that the nature of the duties allows this
• restrictions on travelling both abroad and in Finland
• setting up company rules on temporary quarantines in early phases of the situation for those that have been travelling abroad (also for persons coming from Uusimaa region in Finland to the Olkiluoto site)
• checking that the people accessing the plants have not been in contact with patients diagnosed with COVID-19 infection or come from abroad since the previous two weeks.
The licensees formed specific groups within their organizations that follow the development of the pandemic situation continuously in order to quickly react to the changes and respond accordingly. Special measures to avoid spreading of a corona virus epidemic among the NPP staff and especially among the control room staff have been taken already from the early warnings of the virus. These measures have been tightened gradually with the changes in the national policies of the authorities.
Refuelling outages have been under evaluation, and the availability and need of external personnel and supplies has been discussed with the licensees regularly. Annual fuel exchange and short maintenance period at Olkiluoto NPP were scheduled for spring/summer 2020, and these arrangements were re-evaluated in respect with the pandemic situation. Olkiluoto unit 2 outage was carried out as planned in May 2020 (only a refueling outage with the duration of 8 days). The planned outage of Olkiluoto unit 1 was supposed to be 25 days but it was shortened to 14 days due to action to restrict possible spreading of corona in the plant personnel. The pressure test of Olkiluoto unit 1 reactor pressure vessel (RPV) required by STUK in the decision on periodic safety review in 2018 was postponed by 1 year. Postponing of the pressure test of the RPV was accepted by STUK. Also, other changes to the Olkiluoto unit 1 outage were reviewed and accepted by STUK, but there was no need for deviations, but rather changes to the implementation schedules. In Loviisa NPP, the outages were carried out as planned both in 2020 and 2021.
Measures adopted by the Radiation and Nuclear Safety Authority STUK
STUK has been in a continuous direct contact with the licensees. Most of the government employees were working remotely for two years since mid-March 2020 with the exception of resident inspectors at the site. Concerning the radiation and nuclear safety oversight, STUK has organised its regulatory functions so that most activities can continue normally also in remote mode. This includes document reviews, decision making, meetings with licensees, developing regulations, etc. On-site inspections continued in most safety significant topics at the operating NPPs (Loviisa units 1 and 2 and Olkiluoto 1 and 2) and at the Olkiluoto 3 unit under commissioning where there were no alternative options available. Objective was to minimise the travel needs and also the risk of spreading the coronavirus to the site. Manufacturing inspections done abroad were interrupted due to travel restrictions and instead inspections will be conducted later at the nuclear power plant sites in Finland. STUK has resident inspectors at the NPP sites and objective has been to use mainly them for on-site inspections but if needed, it has been possible to send also additional inspectors from the headquarters (case-by-case decision).
Information security matters have been taken into account also in remote communications by choosing appropriate channels and methods corresponding to the classification of information being transmitted. Remote inspections have been done in areas where it has been possible using conferencing software taking into account the information security restrictions.
During the early phases of the pandemic, STUK raised its licensees awareness of organisational factors in pandemic situation. Pandemic situation affects licensee organisations and may cause many cumulative changes into human performance and related risks, e.g.:
• Temporary guidance (how to ensure that everybody has time to read them and make sure what are currently valid guidance, …)
• Changes to plant modification/ projects implementation and schedules (dependencies needs to be taken into account, formal documentation, up-to-dateness of the plans and guidance, …) – e.g. outages were shortened and some plant modifications/ tests were postponed by one year
• Lack of personnel (deputies with less experience might be used, …)
• Decision making (many decisions due to many changes, overall picture of the effects of the decisions, is there enough time to do multidisciplinary decisions and discussion about risks, …)
• Information flow (less face-to-face meetings, possible misunderstandings and complications in telemeetings, …)
• Mental loading (situation can be more stressfull for some people and can affect the work performance, …).
The conclusion was that even when the staffing of control room personnel and other critical personnel groups will be ensured, situation needed special attention from the organizational factors point of view. Rapid changes in routines, work processes and plans are most common factors behind events and accidents (experience from history). But in the end, there were not any significant findings made in the oversight related to organisational factors.
STUK made also plans for ensuring its internal and external communication activities and particularly its emergency response capabilities. STUK for instance followed sickness rates of its staff to be able to react if needed. During the pandemics, there has not been any challenges identified and sickness rates have been even lower compared to the previous years. STUK also conducted a tabletop exercise on simultaneous radiation emergency and restrictions to see how pandemic restrictions could impact not only operations of emergency organisations but also STUK’s recommendations and decisions.
STUK’s environmental radiation monitoring functions have been continued normally (sampling, measurements and laboratory functions).
One of the lessons learnt from the pandemic situation is that organisations need to be prepared for different kind of hazards. There can’t be separate plans for every detail and certain resiliency is always a strength of the organisation. Typically, business continuity plans (BCP) concentrate mainly on cyber threats or physical hazards that are limited in time. So, one area for improvement is to widen the scope of BCPs both at the licensees and regulatory body for cases like prolonged pandemic. Risk management is also typically an area for improvement, and it should also identify the main risks which need to be prepared by BCP.
In conclusion, Finland has implemented the obligations of the Convention and also the objectives of the Convention, including the principles of the Vienna Declaration on Nuclear Safety are complied with. Safety improvements have been implemented at the Loviisa and Olkiluoto plants since their commissioning. Legislation and regulatory guidance have been further developed. 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, domestic and international operating experience, safety research results, and development of science and technology. Second IRRS mission (the IAEA’s Integrated Regulatory Review Team) in Finaland will be carried out in October 2022. No urgent need exists for additional improvements to upgrade the safety of the Finnish nuclear power plants in the context of the Convention.
Kokoelmat
- STUKin omat sarjajulkaisut [2320]