NUKEM Technologies Engineering Services GmbH (NUKEM), in partnership with Uniper Nuclear Services GmbH (UNS) as part of the UNNU Consortium, has completed dismantling the final reactor pressure vessel (RPV) at Sweden’s Oskarshamn NPP. Between July 2020 and December 2024, NUKEM and UNS dismantled four reactor pressure vessels at the Oskarshamn NPP (units 1&2) and Barsebäck NPP (units 1&2).
The two 600 MWe boiling water reactors (BWRs) at Barsebäck were shut down in 1999 and 2005. Oskarshamn 1, a 473 MWe BWR, was shut down in 2017, and Oskarshamn 2, a 638 MWe BWR, was closed in 2013.
Dismantling of the four RPVs “represents the successful conclusion of an ambitious fleet dismantling project,” NUKEM said. “UNS as the consortium lead, managed post-segmentation and the packaging of the cut RPV components into specialized containers, while NUKEM executed the in-situ segmentation of the RPV and the removal of asbestos insulation between the RPV and the biological shield.”
“By systematically applying lessons learned, we reduced the dismantling time by nearly half from the first to the fourth reactor, demonstrating a remarkable increase in operational efficiency,” said Sergey Molodtsov, Managing Director of Operations at NUKEM. “The project also shows that even the most complex tasks can be carried out successfully, adhering to all safety and radiation protection requirements, and without any incidents.”
The RPV is one of the largest and most radioactively contaminated components of a NPP and dismantling requires exceptional precision and strict safety compliance. The final Oskarshamn RPV was successfully cut into transportable segments and prepared for final disposal. The process incorporated state-of-the-art technology, including a specially developed flame-cutting method and innovative tools that enabled safe handling of radioactive materials while ensuring the safety of the project team. Additional challenges, such as the removal of asbestos-containing insulation, were systematically addressed through comprehensive planning and design.
“We take great pride in having competently delivered this highly valuable decommissioning project together with our consortium partner UNS. This achievement highlights NUKEM’s role as an innovator in the field, continuously fostering strong partnerships across the global nuclear industry,” remarked Nobuaki Ninomiya, Managing Director of NUKEM and its parent company Muroosystems.
“The success of this highly technical and organisationally challenging project is a testament to the collaborative efforts of all involved stakeholders. We extend our sincere thanks to the licence holders BKAB AB, OKG AB and Uniper’s Swedish ND&D programme as well as to our consortium partner UNS for their dedication throughout the project”, noted NUKEM CEO Thomas Seipolt.
NUKEM Technologies Engineering Services GmbH in Karlstein am Main, Germany, is world-wide active in the areas of management of radioactive waste and spent fuel, decommissioning of nuclear facilities, engineering and consulting. For more than 60 years NUKEM has provided high quality products, technologies and services.
NUKEM Technologies GmbH is a nuclear engineering and consulting company managing radioactive waste and used fuel and decommissioning of nuclear facilities. The company is located in Alzenau, Germany. It was established in 2006 as a subsidiary of NUKEM Energy. In December 2009, NUKEM Technologies was sold to Russia’s Atomstroyexport (part of Rosatom) for €23.5m ($25.4m) and transferred in 2019 to Rosatom fuel company TVEL.
In April 2024 it filed for insolvency under self-administration and was under creditor protection, saying the challenges the company was facing were “attributable to the deteriorating business environment due to the ownership structure following the outbreak of war in Ukraine in February 2022”. It was acquired by Muroosystems later that year.