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NDA Annual Report and Accounts 2021-2022 | case studies

Major Sellafield construction project making progress

James Temple at Sellafield

James Temple is Sub-Project Manager for the Windscale Pile 1 Chimney project at Sellafield. He explains progress that saw a huge diffuser removed in the last year.



Tell us about your project?

The Windscale Pile 1 chimney has seen considerable changes over recent years. Its reinforced concrete structure remains contaminated following the Windscale fire in 1957, which poses a significant challenge when it comes to demolition. But it is a challenge the project team is meeting.

The chimney, once 138 metres tall, currently stands at 110 metres after several successful demolition phases. The most recent of these phases was the diffuser demolition project which was completed in March 2022.

The pandemic took its toll on progress, like many projects on the site, but with a collaborative effort by the project team and our supply chain partner the project successfully achieved its challenging milestones.

Crane and equipment working on the Windscale Pile 1 chimney

How does it help contribute towards delivery of the NDA group’s mission?

The removal of the diffuser section marks an important achievement for the NDA’s mission for high hazard reduction and clean-up of the UK’s nuclear sites on behalf of Government. Removal of the diffuser takes us another step forward to creating a clean and safe environment at Sellafield for future generations.

What have the key successes been?

The diffuser structure, sitting on top of the chimney, posed a risk from seismic activity. That risk has been removed. Taking away the diffuser means less potential for fallen objects and minimises care and maintenance costs.

This has all been achieved with no lost time accidents. We have also successfully created a collaborative project with our contracted demolition partner to deliver the work, demonstrating the benefits and importance of collaborative working as decommissioning of the site progresses.

It brings great work satisfaction knowing that the Pile 1 Chimney demolition team is making a visible change to the Sellafield skyline – ‘our one team approach’ concept having contributed to this success.

What learning can be shared as a result of the work?

The main learning we will take forward into future phases of the project and share will be the importance of focusing on human performance and nuclear professionalism whilst adopting all aspects of the Sellafield Ltd manifesto during all aspects of the work. This, combined with a collaborative project team, has meant we have developed a successful, proud, and driven working team.

Find out more:

Sellafield ‘blockbusters’ complete removal of iconic chimney top