Back End Strategy in Lithuania: Interfaces Related Issues and Potential

Solutions

Artūras ŠMAIŽYS

Lithuanian Energy Institute

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 1

Lithuanian Energy Institute

After the decision to use dry storage facility for spent nuclear fuel (SNF) at the Ignalina NPP in CASTOR® and CONSTOR® type casks, back in 1997, LEI started performing studies related to the environmental impacts and safety assessments of SNF handling, storage and disposal.

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018

LEI is acting as:

• Research Institution (scientific studies related to SNF storage and disposal financed by the budget subsidies, H2020 or IAEA CRP)

• Technical Support Organization (support to Regulator in reviewing safety cases; preparation of EIA and SAR for SNF dry storage facility; support to WMO in activities related to the repository development plan, siting program, etc.)

• Contractor or sub-contractor (e.g. in projects related to radioactive waste or SNF management)

2

Ignalina NPP Unit 1 was permanently shut down in the end of 2004, while Unit 2 was shut down in the end of 2009. Currently, reactor cores of both Units are completely defueled.

Unloaded from the reactor core SFAs are transferred into the storage at-reactor pools where they are cooled at least for 1 year. Afterwards SFAs in the “Hot Cell” are cut into the two fuel bundles and loaded into the special 32M baskets that are placed in pools for the wet storage

Nuclear fuel with different U-235 initial enrichment from 2% to 2.8%, without and with erbium absorber was used during operation of INPP

Accumulated amount of SNF is approximately 22000 fuel assemblies

In the beginning of the 90ties a decision was made to build a dry type interim storage for SNF at INPP and store it for 50 years

Overview of the strategy for SNF management in Lithuania (1/5)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 3

SNFSF - 1

SNFSF - 2

At present time there are two dry storage facilities for interim storage of casks with SNF at Ignalina NPP site:

First Spent Nuclear Fuel Storage Facility (SNFSF - 1) – secured site with walls without roof.

New Interim Spent Nuclear Fuel Storage Facility (SNFSF – 2) – building with roof in the secured site

Overview of the strategy for SNF management in Lithuania (2/5)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 4

First Spent Nuclear Fuel Storage Facility (SNFSF - 1):

License for operation was granted in 2000 Storage facility has been extended for several times and currently is filled up to

its final capacity - 20 CASTOR®RBMK-1500 and 98 CONSTOR®RBMK-1500 casks Casks are loaded with intact fuel bundles and contain only 2% U-235 enriched

fuel

Overview of the strategy for SNF management in Lithuania (3/5)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018

CASTOR® RBMK-1500 CONSTOR® RBMK-1500

• Height: ~4.6 m

• Diameter: ~2.1 m

• Weight (loaded): ~75 tons

• Lid system: bolted

• Capacity: 102 FB (51 FA)

• Height: ~4.8 m

• Diameter: ~2.3 m

• Weight (loaded): ~88 tons

• Lid system: bolted & welded

• Capacity: 102 FB (51 FA)

5

New Interim Spent Nuclear Fuel Storage Facility (SNFSF – 2):

License for operation was granted in 2017 Facility is designed to store CONSTOR®RBMK1500/M2 casks Cask can be loaded with SNF having different U-235 enrichments Cask is also designed to store gas-leaking and canned mechanically damaged

fuel bundles Facility have Fuel Inspection Hot Cell

Overview of the strategy for SNF management in Lithuania (4/5)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018

CONSTOR® RBMK-1500/M2

• Height: ~4.8 m

• Diameter: ~2.6 m

• Weight (loaded): ~116 tons

• Lid system: bolted & welded

• Capacity (for intact FB): 182

FB (91 FA)

• Two baskets inside the cask:

32M basket and stationary ring

basket

6

Based on the preliminary investigations of Lithuanian geological structure, crystalline rock and clay were identified as possible formations for deep geological repository. Repository concept (considered for the generic studies) in crystalline rock is based on KBS-3 concept developed by SKB (Sweden) and in clay formations - based on NAGRA (Switzerland) concept.

SNF disposal into deep geological repository is considered as main ultimate SNF management option in “Development Programme for RW Management” which was prepared in 2015 according to EU Directive 2011/70/Euratom. It is expected that deep geological repository will be in operation in 2066 and SNF should be disposed until 2073.

Implementation of SNF management measures, progress assessment criteria, targets, responsible institutions and needed funds are described in the “Development Programme for RW Management”.

“Development Programme for RW Management” also foresees the possibility to elongate the SNF storage at the dry storage facilities for a period over 50 years.

Overview of the strategy for SNF management in Lithuania (5/5)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 7

Storage (from wet to dry)

Government decision to built dry storage facility

Technical Specification

Tender Proposals

Environmental Impact Assessment (Competent authority, public, EIA relevant parties (local authorities, authorities responsible for healthcare, fire prevention, protection of cultural values, etc.), transboundary impact assessment)

Technical Design and Preliminary Safety Analysis Report

License for construction / Construction / Acceptance of construction works

License of operation (according to “Cold” tests results, updated TD & SAR)

License of commercial operation (according to “Hot” tests results, Final SAR)

Periodical Safety Review

Considering the steps of the back-end (1/4)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 8

Dry Storage

Cask acceptance conditions for storage at ISFSF:

• The cask must be consistent with the approved design

• The cask inventory must be covered by the specified Cask Reference Inventory

• Cask loading and completion for storage must be performed in compliance with the approved cask operating cycle plan, the approved individual cask loading plan and the approved instructions for the execution of processes and measurements.

• Leak tightness of the primary lid is within the defined range

• Cask surface temperature is within the defined range

• Radiation dose rate at the cask must be within the specified limit

• The non-fixed contamination of the outer cask surface must be within the specified limit.

• Gas leaking FB (in CONSTOR® RBMK-1500/M2): Maximal amount – 24 per cask

With regular inspections, maintenance and repairs and after investigations of the cask and civil structures, design life of SFSF can be prolonged.

Considering the steps of the back-end (2/4)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 9

Transportation

Currently, cask are transferred only within Ignalina NPP site.

For off-site transport casks comply the requirements for Type B(U) packages. The transport configuration of the cask includes additional components (such as lid and bottom shock absorbers, transport over-pack of the cylindrical part of the cask body)

Design and manufacturing of the cask (criticality, shielding, containment, accident resistance, decay heat removal capability, resistance against ageing, etc.) take into account the compliance of the cask with the transport requirements

Design and safety analyses for the cask transport will be completed at the time of the application of the transport license taking into account the state-of-the-art valid at the time of transport.

Considering the steps of the back-end (3/4)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 10

Reprocessing & recycling

This option presently is not considered for RBMK-1500 spent fuel

??? Molten Salt Fast Reactor (MSFR), Dual Fluid Reactor (DFR) ???

Disposal

Planned site selection stages: site selection process planning (2016–2017), detailed research to choose several regions of interest (2019–2022), detailed characterization (2022–2030), site approval phase (2030–2033).

SNF repacking facility will be necessary

SNF is stored in three different type dry storage casks (transportation, fuel and cans with damaged FB retrieval and other specific issues shall be considered)

Database and records keeping

Considering the steps of the back-end (4/4)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 11

Legal acts (laws, resolutions, requirements) defines responsibilities of the relevant parties involved in the different steps of SNF management

Operator vs Service Supplier

Contract Review Meetings

Monthly Progress Reports

Operator vs Regulator

Annual Reports

Technical Meetings

Regulator vs Public

Public involving in relevant decision making processes

Operator vs Public

Information on media (e.g. website)

Public hearings and meetings

Mechanisms used to facilitate communication

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 12

Storage

Records of processes as cask loading, cask cavity drying, primary lid leak-tightness testing and cask lid welding are attached to the cask individual issue of the Operating Cycle Plan which becomes part of the cask storage documentation along with the fabrication documentation of the cask and separately delivered cask components

SNFSF is provided with a computerized Cask Database and records keeping system

The Cask Database system is based on the Microsoft SQL-Server database system

The storage of the Cask Database data is secured by the use of mirror-hard disks. Periodical backups and archiving of reports on CD or DVD.

At INPP, all data contained in the Cask Database is accessible via Intranet.

Reports can be created according to IAEA requirements (General Ledger; Inventory Change Report; Material Balance Report; Physical Inventory Listing) and EURATOM Reports in XML-Format.

Mechanisms for information management (records retention)

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 13

IAEA Glossary (2016) “knowledge management” - an integrated, systematic approach to identifying, managing and sharing an organization’s knowledge and enabling groups of people to create new knowledge collectively to help in achieving the organization’s objectives.

According to Regulator requirements, Licensee shall ensure that during the operation acquired knowledge and experience of staff should be communicated and accessible

Licensee shall ensure that all relevant information associated with the operation, decommissioning and the safety assessment is properly handled, stored and accessible at all stages of nuclear facility

Operator has procedures, instructions, manuals for certain activities

Records in Cask Database, Cask Passport

Safety Cases

Mechanisms for knowledge management

Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle (EVT1700289), Austria, Vienna, 17 – 19 July 2018 14

Thank you for your attention

15