The final piece of the decommissioning jigsaw to allow access to remove the reactor core at the former Steam Generating Heavy Water Reactor (SGHWR) at Winfrith Site is underway.
The work to completely isolate the reactor from all the plant and equipment that once allowed it to operate is expected to be complete early next year, and will involve the safe removal of 1.5km of stainless steel pipework.
Months of planning and preparation have been necessary because of the complex nature of the project, including the creation of full-scale mock-ups of the plant to allow staff to rehearse the work at minimal risk and learn lessons in the process. Once the steam risers and feeders are removed access to decommission the reactor core will be possible.
Kevin McIntyre, Reactors Programme Manager, said: “The removal of the steam risers and feeders represent the culmination of many years of pre-cursor work, leading to the eventual safe removal of the reactor core, demolition of the SGHWR complex and eventually returning the land to heathland.”
The steam risers and feeders were part of the system which fed water through the reactor to produce steam which drove the turbine when the reactor was operational, and then re-circulated the condensed water.
Significant decommissioning progress over the last two years have meant that major items have already been removed from the reactor, including the heavy water circuits, cooling water circuits, pumps and pressure relief valves, thereby enabling access to the steam feeders and risers.
John Clarke, NDA Chief Executive, said: “It is the mission of the Nuclear Decommissioning Authority to ensure the safe and efficient clean-up of the UK’s nuclear legacy, and therefore this milestone at Winfrith is an important step forward. With a project as demanding and complex as this one, it is important to consider the options carefully. The Magnox Ltd programme team have been thorough in exploring the safest and most cost-effective approach to this project as it moves towards completion next year.”