Sergii Iegan Division on Safety Analysis of Nuclear Facilities IAEA Workshop on Application of the Code of Conduct on the Safety of Research Reactors:

Sergii IeganSergii Iegan

Division on Safety Analysis of Nuclear FacilitiesDivision on Safety Analysis of Nuclear Facilities

IAEA Workshop on Application of the Code of Conduct on the Safety of Research Reactors: Periodic Safety Review, IAEA Workshop on Application of the Code of Conduct on the Safety of Research Reactors: Periodic Safety Review, 2-6 November 2015, Lisbon, Portugal 2-6 November 2015, Lisbon, Portugal

State Nuclear Regulatory Inspectorate of UkraineState Nuclear Regulatory Inspectorate of Ukraine

Application of the Code of Conduct

on the Safety of Research Reactors

in Ukraine

Content Content

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• Introduction

• Research Reactors in Ukraine

• Application of the Code of Conduct on the Safety of RRs

• Periodic safety review of WWR-M

• Conclusions


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IntroductionIntroduction


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Ukraine are operating two research reactors:

•WWR-M which are located on sites of Kyiv Nuclear Research Institute of the National Academy of Sciences of Ukraine;

•IR-100 which are located on sites of Sevastopol Nuclear Energy and Industry University;

Research Reactors in UkraineResearch Reactors in Ukraine


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Main characteristics of WWR-MMain characteristics of WWR-M

The research reactor is in operation since 1960.WWR-M is a light-water moderated and cooled tank reactor with forced cooling. The maximum reactor power is 10 MW.Maximum thermal neutron flux is 1,2*1014 neutron/cm2sec within the core and 6*1013 neutron/cm2sec in the reflector.

Fuel - UO2-Аl. In the beginning the assemblies used were 90% enriched WWR-5M, WWR-7M fuel type, supplied by Russia. Than the reactor core was composed of 36% enriched WWR-2M fuel assemblies, supplied by Russia too. Now the fuel enrichment are limited to 20%.

Experimental Facilities: 10 horizontal channels and 25 vertical channels


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• The IR-100 reactor is heterogeneous

thermal neutron pool type research

reactor using pure ordinary water as

coolant and moderator.• Physical reactor start up was

performed on April 18, 1967;• In 1973 reactor nominal power was

increased up to 200 kW;

• Nuclear fuel: UO2 enriched up to 10%

with 235U ;• Maximum thermal neutron flux

density at the core center is 5.4*1012

neutrons/cm2*sec;

Main characteristics of IR-100


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Role of the StateRole of the State

Legislation framework has been developed and is maintained

Level I represents the Laws of Ukraine (also includes international Convention entered into by Ukraine). Level II represents Resolution of the Cabinet of Ministers and the President of Ukraine. Level II documents determine the strategies of energy development and implementation of the Laws of Ukraine, which are further detailed in NRS regulations.

Level III includes safety regulations for nuclear installations developed by state nuclear regulatory authorities and other central executive bodies. Level IV includes regulatory guides and the utility’s documents. .


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Article 32 of Law of Ukraine “On nuclear energy usage and radiation safety”

Licensee should be fully responsible for the radiation protection and safety of the nuclear installation ... regardless of any activity or responsibility of suppliers or the state regulatory body for nuclear and radiation safety.

Licensee should have financial, material and other resources, appropriate organizational structure and personnel to maintaining the level of safety provided safety rules, norms and standards and requirements issued permit



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Role of the StateRole of the StateSection IV of Law of Ukraine “On nuclear energy usage and radiation safety”

State regulation of safety of use of a nuclear energy provides :establishment of normative criteria and requirements which determine

conditions of use of nuclear installations (normative regulation); granting Licenses and Permits for realization of the activity connected with

use of nuclear installations (licensing);realization of supervision of observance of normative requirements and

conditions of operator licenses (supervision).

State Regulatory Body of nuclear and radiation safety is independent from State authorities, institutions and officials in the field of use of nuclear energy, local authorities and local governments, associations of citizens.

Provisions the State Inspectorate for Nuclear Regulation of Ukraine (approved by Decree of Government of Ukraine)

SNRIU - State Regulatory Body of nuclear and radiation safety


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The Cabinet of Ministers of Ukraine establishes a State Commission on Man-Made and Environmental Safety and Emergencies.

SNRIU performs functions of a competent authority and contact point responsible for transmission and announcement of the information in the case of a nuclear accident according to the Convention on Early Notification of a Nuclear Accident, other international agreements of Ukraine.

Ukraine ratified “Convention on Environmental Impact Assessment in a Transboundary Context” at 1999.


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Role of Regulatory BodyRole of Regulatory BodyResponsibilities of SNRIU:

•Issues licenses (permits for work or operations) in the established order activity of operating organizations at a particular stage of the operation life of nuclear installations

•Performs state supervision on observance of nuclear and radiation safety laws, standards, and requirements, physical protection of nuclear installations

•Applies within its powers enforcement measures to legal entities and individuals in case of breaking laws, rules and standards on nuclear and radiation safety, nuclear and radiation safety requirements, physical protection of nuclear installations, nuclear materials, radioactive waste other sources of ionizing radiation, as well as conditions, listed in the issued licenses

Requirements and decisions of SNRIU (including the decision-making process related to safety) publicly available


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Periodic safety review of WWR-MArticle 33 of Law of Ukraine “On nuclear energy usage and radiation safety”

The operating organization (operator) must periodically, in accordance with the norms, rules and standards of nuclear and radiation safety, perform safety reassessment of nuclear facilities or storage for radwaste disposal, and submit reports on its results to the state regulatory body for nuclear and radiation safety.

Safety reassessment also carried out on the request of state regulation of nuclear and radiation safety in the event of significant changes in design facility or storage, and when operating experience indicates weaknesses the previous safety assessment.

The requirements for the frequency and scope of PSR of RR’s have not been established by regulatory documents.

The process of reassessment is regulated license conditions (the deadline, reassessment the main issues, ...)

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Periodic safety review of WWR-M (cont.)May 2002 – license to operate of WWR-M

Basis: SAR

license conditions: lifetime was limited – 31.12.2005

December 2005 – 1-st lifetime extended (changes in the license)

Basis: updated SAR (considered modernization)

license conditions:-lifetime was limited – 31.12.2008-in case the operator decide to continue operating after 2008 PSR report should be presented to SNRCU - 30.08.2008


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Periodic safety review of WWR-M (cont.)December 2008 – “temporary” shutdown

Basis: results of regulatory review of PSR report

In PSR report was missed (or not provided in full) information on the following key aspects, based on an analysis which should take a decision on the possibility of extension of operation:•Analysis of operating experience, including analysis of violations;•Radiation protection personnel and research reactor impact on the environment during normal operation;•Assessment of building structures;•Analysis of radioactive waste management;•Analysis of accidents;•Removal of reactor operation.

SNRCU’s conditions for recovery operation: removal of comments to the PSR report


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Periodic safety review of WWR-M (cont.)May 2009 – 2-nd lifetime extended (changes in the license)

Basis: new PSR report, which also included missing information.

For the development of the PSR report has been applied "Requirements for the structure and content of the PSR report of existing nuclear power plants. SOU-N YAEK1.004.2007” taking into account design features and especially the operating of research reactorsSFs, which have been assessed:•design of RR•current technical state of systems and elements•equipment qualification•ageing•safety analysis•operational safety•using experience of other RRs and results of scientific researches•organization and management•operating documentation•human factor•emergency preparedness and planning•impact on the environment


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Periodic safety review of WWR-M (cont.)May 2009 – 2-nd lifetime extended (changes in the license) (cont.) license conditions:Lifetime was limited – 31.12.2013PSR report should be update in part: •Chapter “safety analysis” should includes a clear distribution of BDA and BDBA, an analysis of extreme external events and human error•Chapter “Decommissioning” should be update, based Decommissioning program of nuclear research reactorAMP on equipment and pipelines should be developedAnalysis of accidents related to the immediate destruction of core support grid should be done or justify refusal to consider such an accident

In case the operator decide to continue operating after 2013 should be presented to SNRCU: -results of current technical state of systems and elements-results of executing license conditions -Solution on opportunities and conditions for further safe operation


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Periodic safety review of WWR-M (cont.)December 2013 – shutdown for maintenance and repair (changes in the license)

Basis: results of regulatory review of results of executing license conditions and results stress- test (natural and man-made hazards or a combination of hazards, loss of power and loss of power or ultimate heat sink, severe accident management and emergency response)

In justification documents was missed:-detailed information on the current state of systems and components research reactor-updated Chapter “safety analysis” PSR report-results of the severe accident analysis -detailed analysis of the impact of extreme events on performance systems important to safety, are not considered combination of extreme events, not the analysis relative to spent fuel in pool (stress- test )-not yet complete replacement the primary circuit piping, which was found defect (crack)

SNRCU’s conditions for recovery operation: removal of comments to the PSR report

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Periodic safety review of WWR-M (cont.)December 2013 – shutdown for maintenance and repair (changes in the license) (cont.)

SNRIU’s conditions for recovery operation:

- Final revision of the Chapter “safety analysis” PSR report- Final revision of the stress- test report- Giving new strength calculations elements of reactor and primary circuit piping- Replacement the primary circuit piping, which was found defect (crack)


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Periodic safety review of WWR-M (cont.)December 2014 – 3-rd lifetime extended (changes in the license)

Basis: results of regulatory review of Solution on further possibilities and conditions for safe operation of research reactor WWR-M and:•Updated Chapter “safety analysis” RSR report•Updated stress- test report•new strength calculations elements of reactor and primary circuit piping•Results of replacement the primary circuit piping, which was found defect (crack)

license conditions:-lifetime was limited – 31.12.2023-in case the operator decide to continue operating after 2023 PSR report should be presented to SNRCU before 31.12.2021


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Conclusions

• Most of the requirements of Code of Conduct on the Safety of RRs in Ukraine are meet.

• The regulatory framework of Ukraine is under reviewing. The new documents will take into account IAEA recommendations, national and best world practices.

• Reassessment of safety of RRs in Ukraine to perform regularly. PSR report used for the licensing process


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Thank you for your attention!

Documents

Sergii Iegan Division on Safety Analysis of Nuclear Facilities IAEA Workshop on Application of the Code of Conduct on the Safety of Research Reactors: