Another decommissioning contract for a nuclear power plant in the USA

Between 2010 and 2015, SIEMPELKAMP technology and expertise for the effective dismantling of core internals and reactor pressure vessels in the USA were already in high demand. “Here we supplied both the necessary special tools and the required technical support for sawing up the core internals and thermally cutting up the reactor pressure vessels of the Zion nuclear power plant in the state of Illinois, USA,” reports Christian Jurianz, who is responsible for the project at SIEMPELKAMP.

In particular, the first-time use in the USA of remote-controlled flame-cutting technology to cut through the thick reactor vessel wall formed the basis for further decommissioning activities by Siempelkamp NIS Ingenieurgesellschaft mbH (SIEMPELKAMP NIS) in North America. On the basis of this reference, another contract in the USA has now been realized.

The new dismantling contract concerns two pressurized water reactors from Combustion Engineering, which were commissioned with an electrical output of 1,070 MW in 1983/1984 and permanently shut down in 2013 for economic reasons.

With a project volume of 4.4 billion US dollars, this decommissioning project in California is without doubt the largest of its kind to date. Over the course of ten years, all necessary decommissioning activities will be carried out, the site will be recultivated, and the radiation level will be reduced to such an extent that the site can be used subsequently without restriction. The work will be carried out in strict compliance with California’s environmental regulations – this decommissioning project will create approximately 600 jobs over the entire period.

From 30% to 100%: project phases

In an initial phase, NIS was commissioned to prepare a more detailed concept (30% design), i.e. NIS examined the feasibility of the dismantling steps, defined the necessary dismantling tools, and specified the dismantling locations. This phase in particular is naturally characterized by a high degree of creativity. At the same time, it is inevitable that solution approaches will also be discarded again. All of this takes place under great time pressure, as the customer wants to have the required dismantling tools available and ready for use on the power plant site after only 20 months.

This concept phase was followed by the phase of detailed engineering design of the tools (100% design) down to manufacturing depth and the interaction of the individual components, combined with the higher-level equipment for remote control and video monitoring of the dismantling processes.

In the meantime, NIS has been able to prepare the 30% design for both the core-internals dismantling and the reactor pressure vessel dismantling to the customer’s complete satisfaction and obtain approval. The 100% design for the dismantling equipment for the core internals was also completed on schedule and approved by the customer. The customer’s main interest is now focused on the on-schedule manufacture of the tools. Their manufacture is carried out exclusively at the Siempelkamp Maschinenfabrik in Krefeld.

At the end of manufacturing, the customer will subject the machines to an extensive acceptance test, putting them through their paces, as well as testing their interaction with the video technology and the higher-level control system. This will take place in a mock-up test under realistic conditions, in some cases also under water. We will report on this …

The negotiation team of Siempelkamp NIS Ingenieurgesellschaft mbH

Christian Jurianz, graduate engineer in nuclear power plant technology, employed at SIEMPELKAMP since 2001. Overall project manager in his capacity as managing director of Siempelkamp Ingenieur und Service GmbH.

Dr. Aldo Weber, Dr. rer. nat. in physics, employed at Siempelkamp NIS Ingenieurgesellschaft mbH since 2007. Initially responsible as division manager for the Information Technology and Consulting division, including determining the decommissioning costs of nuclear facilities and services related to operation. Since 2015, spokesperson of the management of Siempelkamp NIS Ingenieurgesellschaft mbH, based in Alzenau. In this role, he is responsible for operations, which also include remote-handled decommissioning of large components, decontamination of primary-circuit components, and the planning and supply of systems for waste treatment in nuclear facilities.

Stefan Dätig, graduate engineer (University of Applied Sciences), with SIEMPELKAMP since 2009. As a design engineer, he worked on further developing the flame-cutting process with a manipulator-guided torch. His experience during the RPV dismantling at the Stade nuclear power plant led to responsible tasks in Zion, USA: from March 2011, he was on site as a planning engineer with design tasks for the equipment for dismantling the RPV internals at the Zion nuclear power plant. He later took over project management for the design and procurement of the entire RPV dismantling equipment, including factory acceptance tests, mock-up, and installation on site, followed by heading a group in plant engineering and decommissioning. Since January 2016, Stefan Dätig has been head of department in the Decommissioning and Consulting division.

Andreas Loeb, graduate electrical engineer, with SIEMPELKAMP since 2003. Until 2008, he was overall project manager responsible for the “Dismantling of the RPV and RPV internals of the MZFR Karlsruhe” project. From 2010, as head of the “Decommissioning” department, he was also overall project manager responsible for the “Dismantling of the RPV at the Stade nuclear power plant” project. In addition, he took over sales and project management in Germany and abroad, in particular for the decommissioning of primary-circuit components. Since 2016, Andreas Loeb has been division manager responsible for the Decommissioning and Consulting division at Siempelkamp NIS.