In March 2011 the Swedish nuclear industry applied for a license to build a repository for final disposal of spent nuclear fuel. The repository has to be tightly sealed for hundreds of thousands of years. But in a worst-case scenario the copper canisters may rust and start to leak after only some hundreds of years.
[pdf] MKG Report 4 "Comments from the Swedish Society for Nature Conservation, SSNC, and the Swedish NGO office for Nuclear Waste Review, MKG, on the industry's, SKB, research programme Fud-07" >>
(pdf) MKG Report 2 "Final Deposition of High-level Nuclear Waste in Very Deep Boreholes – An evaluation based on recent research of bedrock conditions at great depths", December 2006 >>
The government has on Jan 27 2022 taken a decision to approve the repository license application despite outstanding copper corrosion issues. Read more about this here >>