Speaker
Description
Maisiagala Radioactive Waste Storage Facility (MRWSF) in Lithuania is a Radon type disposal facility that had been in operation from 1963 till 1988 and was closed in 1989. It consists of a subsurface concrete vault with an overall volume of about 200 m3. The vault was filled to about 60 % with legacy radioactive waste (RW), ~114 m3) generated at industrial, medical, military and scientific research institutions. The RW was grouted layer by layer inside the vault cells. Since 2002 it has been supervised by the SE Radioactive Waste Management Agency (RWMA) established in 2001 to deal with RW disposal. In 2019, after reorganization by merging RWMA to SE Ignalina NPP the supervision of MRWSF was transferred to Ignalina NPP which is also is charge of MRWSF decommissioning.
Based on the results of safety assessment, in 2006 MRWSF was upgraded. Two protective HDPE membrane layers were installed on the top of the vault to prevent penetration of precipitation. After upgrading, MRWSF was licensed as an RW storage facility. However, high activity Cs-137 and Co-60 as well as long-lived disused sealed radioactive sources (DSRS) were placed into the vault during its operation, and hence this facility does not meet long-term safety requirements.
In 2016 the decision was taken to retrieve RW from MRWSF and transport it to Ignalina NPP for further management. The site of MRWSF shall be remediated and released for unrestricted use. In 2011 Preliminary Decommissioning Plan of MRWSF was developed. In 2018 EIAR and FDP of MRWSF were developed and approved by the regulator and other state institutions. In 2020 Description of Decommissioning Project, SAR, Radionuclides Discharge into the Environment Plan and Radiation Protection Programme were developed and approved by the regulator. In 2021 Demolition Project was finalised. The tendering for installation of the support infrastructure for decommissioning has started. It is planned to finish the retrieval of RW from the site and to transfer it to Ignalina NPP in the beginning of 2023.
In the paper, a detailed description of MRWSF and the waste loaded in the vault will be provided. The selection of the decommissioning strategy based on the MCDA analysis will be described. The auxiliary systems designed in the Demolition Project for the retrieval and transport of RW to Ignalina NPP will be analysed. Main safety issues analysed in the Safety analysis report and their results will be highlighted.
| Speaker's title | Mr |
|---|---|
| Affiliation | Lithuanian Energy Institute |
