During the continuous monitoring of the Maišiagala RWSF, a small amount of tritium was found in the water of the special monitoring boreholes near the storage facility. It should be noted that the amount of tritium did not exceed the permissible norms. Moreover, the water did not reach even the nearest water bodies or the wells of residents. However, this highlighted the need to strengthen the protective barriers of the storage facility, which were built during the Soviet times to prevent the release of radioactive substances into the environment. Therefore, in December 2002, the European Commission allocated the funds and confirmed the PHARE project “Maišiagala RWSF Safety Assessment and Improvement”, the main objective of which is to improve the radiological safety of the environment of the storage facility.
The project was implemented in 2006. The main stage of the project is the installation of new protective barriers for the storage facility. According to the project developed by French specialists, additional protective barriers – a system of a soil layer and two waterproof membranes – were installed above the basement with radioactive waste. These barriers protect the RW stored in the facility from water. This is essential to ensure that radioactive substances are not released into the environment through water.
The entire territory of the storage facility was fenced with the special double fence, and cables were laid to detect movement. Video cameras were also installed to monitor the territory. The mentioned measures ensure the physical security of the storage facility, i.e. they prevent undesirable persons from accessing the RW storage site.
The US Department of Energy has made a significant contribution to improving the physical security of the Maišiagala RWSF. In 2004, the mentioned department provided support for the design and installation of a continuous monitoring system for the storage facility.
During the surveillance of the closed storage facility and the assessment of the inventory and physical properties of the radioactive waste contained therein, it was found that the waste placed in the storage facility was not sorted and did not meet the actual safety requirements, and that the barriers installed on the ground surface could not ensure long-term safety against the release of radionuclides and the storage facility could not be transformed into a repository. Therefore, it was decided to decommission the Maišiagala RWSF and to transfer all RW from the Maišiagala RWSF to the SE Ignalina NPP for storage.
For this purpose, in 2016, the implementation of Project No 05.2.1-APVA-V-010-01-0003 “Decommissioning of the Maišiagala Radioactive Waste Storage Facility” (hereinafter – the Project) financed by the Cohesion Fund of the European Union Structural Funds, was started with the aim of protecting the environment from a potential threat by retrieving the RW stored in the Maišiagala RWSF and recultivating the site of the storage facility.
The activities of the Project are divided into the following stages:
- Stage 1 provides for the coordination of the technical and licence documents required for the retrieval of the RW from the storage facility, the design and installation of the temporary infrastructure at the storage site to be used for the retrieval of the RW, and the transportation of all the waste stored in the storage facility to the SE Ignalina NPP.
- Stage 2 provides for the dismantling of the installed temporary storage infrastructure used for the retrieval of the RW, the removal of all remaining waste from the storage facility site, the clean-up of the site and the abolition of its radiation control, and the transfer of the site for other uses.
- Until 2019, the State Enterprise Radioactive Waste Management Agency (RATA) was responsible for the implementation of the Project, and from 2019 – the SE Ignalina NPP.
- The strategic indicator for Stage 1 of the Project has been set to control the project and the investment of the project funds, i.e. to transport 300 m3 of the RW from the Maišiagala RWSF to the SE Ignalina NPP by the end of 2023.
At the beginning of 2024, all the technical, design and licence documents necessary for the decommissioning of the Maišiagala RWSF were received, construction works for the installation of the temporary infrastructure at the storage site were carried out, and the strategic indicator for Stage 1 of the Project was achieved (the amount of 328.79 m3 of the RW was transported to the SE Ignalina NPP by the end of 2023).
In order to continue the implementation of the Project, preparations for the activities of Stage 2 of the Project are currently underway, however, due to the unforeseen amounts of the RW indicated in the historical documents, the implementation of Stage 1 of the Project is being continued. The relevant activities for the transportation of the RW are expected to be completed in the beginning of Q2 2024. At the same time, in Q2 2024, after obtaining the conditions from the Project controlling authorities and evaluating these conditions, it is foreseen to revise the objective of the Project regarding the decision to demolish the temporary infrastructure installed at the Maišiagala RWSF.
During the implementation of the activities of Stage 1 of Project 6101, in order to carry out all the decommissioning works at the Maišiagala RWSF, taking into account the costs of radioactive waste management and storage, as well as other necessary costs, the funding allocated for the implementation of the Project was revised and increased to 14 million 883 thousand euros, and the deadline for the achievement of the planned strategic indicator for Stage 1 was extended to 31 December 2023.
As part of the implementation of the activities of Stage 1 of the Project, the Environmental Impact Assessment Report on “Decommissioning of the Maišiagala Radioactive Waste Storage Facility” was prepared and coordinated with relevant authorities in 2017–2018, and on 5 June 2018 the competent authority (the Environmental Protection Agency) adopted a decision on the acceptability of the “Decommissioning of the Maišiagala Radioactive Waste Storage Facility” in terms of environmental impact. The decision states that the proposed economic activity “Decommissioning of the Maišiagala Radioactive Waste Storage Facility” is acceptable under the time-based alternative of immediate decommissioning as presented in the Environmental Impact Assessment Report.
In the period 2017–2018, the Final Decommissioning Plan for the Maišiagala Radioactive Waste Storage Facility was also prepared and, after coordination with the relevant authorities, approved by the Order of the Minister of Energy of the Republic of Lithuania, No 1-272 of 5 October 2018. It provides a detailed plan for the implementation of the decommissioning process of the Maišiagala RWSF.
To be allowed to carry out the decommissioning of the Maišiagala RWSF, the SE Ignalina NPP was obliged to obtain a licence for the decommissioning of nuclear facilities issued by the State Nuclear Safety Inspectorate (VATESI). Therefore, in 2019–2021, preparatory works were carried out and documents necessary for obtaining a licence for the decommissioning were prepared. Since it was planned to transport radioactive waste from the Maišiagala RWSF to the Ignalina NPP, considerable attention was also paid to the preparation and coordination with the regulatory authorities of the documents necessary for obtaining a licence for the transport of nuclear fuel cycle materials and nuclear and fissile materials listed in Annex 1 of the Law on Nuclear Safety in specified quantities.
In the framework of the Contract for the provision of services for the preparation of the licencing, technical and design documentation for the decommissioning of the Maišiagala RWSF, signed on 18 April 2019, the following documents have been prepared: Project Description for the Decommissioning of the Maišiagala RWSF (agreed on 2 October 2020), Technical Design Documentation (Demolition) of the Maišiagala RWSF (approved on 8 March 2020), Safety Analysis Report for the Decommissioning of the Maišiagala RWSF (approved on 31 August 2020), Radionuclide Release Plan for the Decommissioning of the Maišiagala RWSF (approved on 10 September 2020), and Radiation Protection Programme for the Decommissioning of the Maišiagala RWSF (approved on 5 October 2020).
In accordance with the Agreement on the analysis of the consequences of possible nuclear and radiological accidents, signed on 6 June 2019, the relevant documents for the Maišiagala RWSF were prepared, and then accepted by VATESI on 10 April 2020.
In accordance with the Resolution of the Government of the Republic of Lithuania, No 1872 of 3 December 2002 “On the Approval of the Description of the Procedure for the Submission of Data to the European Commission on the Activities Related to the Disposal of Radioactive Waste", the SE Ignalina NPP prepared the General Data Summary (hereinafter – the Summary) for the decommissioning of the Maišiagala RWSF, which was agreed by VATESI on 26 June 2020; further, the Summary was submitted to the European Commission and agreed on 16 April 2021.
In the period 2020–2023, other documents were also prepared for obtaining the above-mentioned licences for ensuring physical, radiological, nuclear safety and environmental protection during the decommissioning of the Maišiagala RWSF. Regular working meetings were organised with VATESI, the Ministry of Environment, the Ministry of Energy, the Ministry of Finance and other state institutions, organisations and municipalities to present and discuss the progress of the Project implementation and to resolve relevant issues.
On 13 May 2021, VATESI issued the licence to the SE Ignalina NPP to carry out the decommissioning of the Maišiagala Radioactive Waste Storage Facility Licence Information System (licencijavimas.lt).
On 30 March 2021 and 1 April 2021, the State Territorial Planning and Construction Inspectorate under the Ministry of the Environment (VTPSI) and the administration of Širvintos District Municipality issued the construction permit documents required for the installation of temporary infrastructure necessary for the radioactive waste retrieval process at the Maišiagala RWSF site.
In the period 2020–2022, the public procurement processes required for the implementation of Stage 1 of the Project were initiated, and procurement contracts for various activities of Stage 1 of the Project were concluded and implemented. The purchased equipment and supplies are used to ensure the safe retrieval of the RW.
On 18 July 2023, VATESI issued the licence to the SE Ignalina NPP to transport nuclear fuel cycle, nuclear and fissile materials Licence Information System (licencijavimas.lt).
During the performance of the Contract for the execution of preparatory works for demolition of the Maišiagala RWSF structures, signed on 5 April 2022, the contractor undertook to perform works for the construction of temporary structures and installation of temporary infrastructure necessary for the retrieval of the radioactive waste from the Maišiagala RWSF. Accordingly, the contractor has installed the necessary infrastructure: it has constructed and installed temporary structures, engineering networks and communications, including the nuclear facility structure of a multi-layer slabs (“caisson”).
Due to the insufficiencies of the design documentation and other unforeseen circumstances, four (4) modifications were implemented during the construction of the temporary infrastructure under the relevant contract: modification of the works during the cold period of the year, modification of the caisson and the entire temporary infrastructure changing (displacement), elevation of the structures (primary cover) due to the requirements for the crane as an important to safety structure, modification of the length of the rail of the container transfer trolley due to the different position of the RWA basement “r1” from the one specified in the design documentation. The contractor’s delay in fulfilling its contractual obligations, due to these and other circumstances, resulted in the full completion of the relevant contract only on 29 December 2023.
During the implementation of the Project, unforeseen circumstances related to the unexpected amount of radioactive waste at the Maišiagala RWSF were encountered, and the solution was proposed and agreed with the regulatory authorities to start the transportation of the waste before the completion of the above-mentioned contract. This allowed that the strategic indicator for Stage 1 of the Project, i.e. to transport 300 m3 of radioactive waste from the Maišiagala RWSF to the Ignalina NPP by 31 December 2023, was achieved by the specified deadline (30 December 2023, inclusive) – 328.79 m3 of radioactive waste was transported from the Maišiagala RWSF and delivered to the Ignalina NPP. Thus, the strategic indicator for the project stage was already achieved on 27 December 2023, when 306.39 m3 of radioactive waste was transported from the Maišiagala RWSF, thereby ensuring the investment of the European Union Structural Funds for the achievement of the strategic indicator for the Project.
As of 1 January 2024, having achieved the strategic indicator for Stage 1 of the Project and having invested the necessary part of the European Union Structural Funds, the SE Ignalina NPP is continuing the implementation of this stage until all RW is removed from the Maišiagala RWSF (the activities of this stage will be continued using funds from the State budget). In parallel, the activities of Stage 2 of the Project are being prepared, i.e. the documents necessary for the dismantling of the Maišiagala RWSF storage facility, temporary infrastructure and other structures are being developed. After the retrieval and transport of all RW from the Maišiagala RWSF, the SE Ignalina NPP will perform the works for dismantling the temporary infrastructure, carry out the necessary investigations and prepare the documents required for the termination of the licence for the decommissioning of the Maišiagala RWSF. After the termination of the licence, the Maišiagala RWSF site will be transferred to other uses.
Ignalina NPP decommissioning activities are co-financed by European Union
