The existing Ukrainian radioactive waste storage and disposal facilities comprise:
- Six interregional state specialized enterprises called "Radon" for storage of radioactive waste and spent radioactive sources resulting from medical, research and industrial applications.
- Various disposal and storage points of radioactive waste created after the Chornobyl accident within the Chornobyl exclusion area.
These facilities do not satisfy modern safety requirements because some of them were created almost 50 years ago, while others were constructed urgently after the Chornobyl accident; therefore the storage facilities require a thorough safety re-assessment. Safety assessments must also be performed for the existing disposal facilities at “Radon” sites in order to properly assess their impact on personnel, public and the environment. The aim of the safety re-assessments is to make well-funded decisions on the necessity and sequence of radioactive waste removal from these legacy facilities. The radioactive waste selected for removal is then to be filled in containers and transported for long-term storage / disposal in the facilities of the "Vektor" complex. In addition, the existing barriers of the old disposal facilities shall be strengthened to ensure the safe storage of the remaining radioactive waste that cannot be removed safely.
The reconstruction of the existing "Buryakivka" disposal point is also planned, in order to extend its capacity to dispose the low-level radioactive waste generated during the construction of the New Safe Confinement (NSC), as well as during the remediation activities within the exclusion area. Note that "Buryakivka" is the only operating near-surface radioactive waste disposal facility in Ukraine located within the Chornobyl exclusion zone (CEZ). Obviously, the design for the extension of the "Buryakivka" disposal facility should be based on the safety re-assessment results of the existing radioactive waste disposal facilities at the site.
In addition, the following RAW disposal facilities are located at the "Vektor" site in the CEZ:
- near-surface disposal facilities (SRW-1 and SRW-2, is under construction);
- Engineered near-surface disposal facility for low and intermediate level, conditioned RAW from Chornobyl NPP (Lot-3 of the ICSRM, Industrial Complex for Solid RAW Management).
Construction of Lot-3 is finished and the Operator received operation license for two compartments with restrictions, due to the imperfect safety analyses and applied methodologies. To meet the license conditions the operator should perform additional analysis of stability of disposal facility structures, reassess safety with introduction of modern methodologies and use of substantiated input data and update Waste Acceptance Criteria (WAC) accordingly.
The construction of the following RAW facilities is also planned at the "Vektor" site:
- facilities for long-term storage of spent ionizing radiation sources (IRS);
- Interim storage facilities for long-term storage for long-lived intermediate-level waste, high level waste and vitrified, heat-generating high level radioactive waste originated from reprocessing of spent nuclear fuel of the operating Ukrainian NPPs of VVER-1000 type.
The main technical objective of this INSC project was to develop guidelines and to provide assistance to the SNRIU, the nuclear safety regulator of Ukraine, during the assessment of licensing documents dealing with safety issues related to various radioactive waste management facilities in Ukraine. The overall objectives of this INSC cooperation with the Ukrainian nuclear safety authority were as follows:
- Strengthening SNRIU capabilities in safety assessments related to the licensing of radioactive waste management facilities to be constructed or reconstructed in Ukraine.
- Development of appropriate criteria, methodologies and procedures for the design and licensing of radioactive waste management facilities.
- Improvement of interaction and dialogue with industrial partners (e.g. facility operators) and with other regulatory authorities and their TSOs, at every stage of the licensing process.
- Ensuring transfer of experience to the SNRIU and to its TSO, by involving local experts in technical discussions and activities.
The assistance project was justified by the fact that in Ukraine large amounts of radioactive waste are stored at various temporary storage facilities, mainly close to the places where the waste were generated. In order to ensure proper long-term storage or safe disposal in specialized facilities, the waste must be appropriately processed, conditioned and then disposed.
The contract was signed between the European Commission and RISKAUDIT on 28 November 2011, initially for a two-year period, later extended to 28 months. Five European TSOs were involved in the project managed by RISKAUDIT: GRS (Germany), IRSN (France), Bel V (Belgium), ITER-Consult (Italy) and STUK (Finland), with SSTC NRS (Ukraine) acting as the local TSO.
The project was divided into three technical tasks, subdivided into two to four subtasks.
Task 1: Development of services resulting from the industrial RAW management activities
In this task two methodological documents (guidelines) were developed, establishing criteria for assessment of the impact on environment and population of a site with multiple radioactive waste management facilities (subtask 1a) and defining up-to-date methodologies for safety assessment and reassessment of existing radioactive waste disposal facilities (subtask 1b). These guidelines were later used as reference documents when carrying out tasks 2 and 3 of the present project.
Task 2: Support for licensing of new radioactive waste management facilities
Task 2 was divided into four subtasks: subtask 2a dealt with the assessment of safety-related documents for the licensing application of the SRW-1 and SRW-2 disposal facilities, including Safety Analysis Report (SAR) and WAC. The review of the SWR-1 and SRW-2 SAR documents resulted large number of comments and the revision of the SAR was strongly recommended.
The WAC document was not submitted to SNRIU by the Applicant. Therefore, the second part of the sub-task 2a could not be carried out as planned, due to the lack of documentation to review.
The objective of the subtask 2b was to provide technical support to SNRIU to solve some important open safety issues encountered in the licensing process of the ICSRM Lot 3 (water ingress, seismic calculations, methodology of long term safety assessment adapted for “Vektor” site, etc.).
The conclusion of subtask 2b was that some improvements could be observed in the safety approach presented by the Applicant. It was also concluded that many comments made by SNRIU to the SAR Rev.1 of Lot 3 were not adequately addressed by the Applicant; therefore the preparation of SAR Rev. 2 was initiated.
Sub-task 2b was completed according to the Inception Report.
Sub-task 2c concerned the assessment of safety-related documents on interim storage facilities for long-term storage of long-lived intermediate-level waste (LL-ILW), high-level waste (HLW) and vitrified, heat-generating high level radioactive waste on the "Vektor" site.
In sub-task 2c it was originally planned that the applicant would submit to SNRIU three design criteria documents related to the three storage facilities. It was also expected that the conceptual design of the storage facilities developed on the basis of the design criteria would be completed by issuing preliminary safety analysis reports (PSAR). Finally only the design Terms of Reference documents related to the LL-ILW and HLW storage facilities were submitted by the Applicant and assessed by the EU experts.
Subtask 2c was therefore only partly completed, due the lack of documentation to review.
Subtask 2d concerned the assessment of Technical Specifications and revised SAR of the spent ionizing radiation source (SIRS) storage facility, to be constructed on the “Vektor” site, for which SNRIU had approved the design with conditions only. Many shortcomings were identified in the submitted SAR of the SIRS, leading to request revised versions of the SAR and the Technical Specifications.
Sub-task 2d was completed according to the Inception Report, but follow-up activities should be considered.
Task 3: Safety re-assessment of existing radioactive waste disposal facilities (SE "Radon", RWDP "Buryakivka")
Task 3 dealt with the safety re-assessment of existing facilities: the "Buryakivka" radioactive waste disposal point (subtask 3a) and selected SE “Radon” facilities (sub-task 3b).
Sub-task 3a included assessment of long-term safety justification of the existing RWDP Buryakivka, located within the CEZ. An extension of this work has also been performed, i.e. the PSAR dedicated to the increase of capacity of the disposal site was also assessed. The conclusion of this assessment was that the long-term safety of the Buryakivka disposal facility was not yet proven and the addition of new waste disposed externally on existing trenches would make the situation even worse.
In sub-task 3b expert review of the "Safety reassessment report for RAW storage facilities of Kharkiv State Interregional Specialized Enterprise (SISE)" and its fourteen Annexes was carried out. The review concluded that the safety of the Kharkiv storage/disposal facility operated by SISE is not sufficiently proven and new safety reassessment is necessary, taking into account the requirements of the guideline developed within sub-task 1b.