15.4 Site area (Hectares)
69 Station lifetime output of electricity (TWh)

Current phase: C&M Preparations

Trawsfynydd is located on a 15.4 hectare site, on an inland lake in Snowdonia National Park, North Wales. Trawsfynydd was the first inland civil Magnox nuclear station and drew its cooling water from Llyn Trawsfynydd. It started service in 1965 and generated 69 TWh of electricity over the 26 years until it ceased electricity generation in 1991 for a routine outage. Permanent shut down was announced in 1993. Along with Bradwell it is one of two Magnox sites selected for accelerated entry to C&M.

Key near term activities

Currently in C&M preparations, Trawsfynydd is a key site in the NDA portfolio as it is one of the accelerated sites trying to achieve early C&M entry.

The work is focused around key hazard reduction projects and maintenance of key assets, including the reactor safestores and the new ILW store. Key projects include clearing and cleaning the resin and main sludge vaults  and commissioning retrieval equipment and retrieving FED. Recovered wastes will be treated and solidified for transfer to the ILW store.


The site has discharged over half the work required to achieve C&M with significant key hazard reduction milestones achieved including emptying resin vault one and significant emptying of the ponds north void.

Good progress has been made to enabling commencement of the FED retrieval project with active commissioning expected in 2013/14. Progress has also been made on safestore preparations for C&M.


Small and Medium Enterprises (SMEs) are a key link in our supply chain and Magnox is committed to supporting the SME agenda for growth.

Opportunities for contracts and ways to become a supplier are set out in the main Suppliers pages of this website.


Site Stakeholder Groups (SSG) are long-established at each of the Magnox sites and provide an opportunity for stakeholders to find out more about the work being undertaken there.

Independently-chaired, the SSG meets regularly to examine our work, as well as that of the Nuclear Decommissioning Authority (NDA) and regulators. The SSG’s membership includes local councillors, non-governmental organisations and other interested stakeholders.

If you would like to apply for socio-economic funding please visit:

Community Events

1st October 2015

Trawsfynydd Site Stakeholder Group meeting starting at 14:00, NDA Strategy 3 Consultation


Conference and Induction Centre, Trawsfynydd Site

Meeting Documents:

Associated Documents:

7th December 2015

Trawsfynydd Site Stakeholder Group meeting


Conference and Induction Centre, Trawsfynydd Site

Meeting Documents:

5th December 2016

Trawsfynydd Site Stakeholder Group meeting - Dec 16


Conference and Induction Centre, Trawsfynydd Site, 10:00 (10am)

Meeting Documents:

Associated Documents:

View all reference documents

Contact Secretariat:

Jill Callander, SSG Secretariat Co-ordinator
Magnox Ltd, Chapelcross, Annan, Dumfriesshire, DG12 6RF
Telephone: 01461 208701
Mobile: 07515190595

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