Trawsfyndd intermediate level waste store; Trawsfyndd intermediate level waste store;

Trawsfynydd Intermediate Level Waste Store, Gwynedd, Wales

Site clearance, design and construction of a new nuclear waste store

The Trawsfynydd Decommissioning Site is a former nuclear power station in the Snowdonia National Park, North Wales. Magnox Limited is the site license holder.

The station was formally closed in 1993, and is now in the process of being decommissioned.

The project scope includes construction of a new store building for intermediate level waste (ILW) containers, height reduction and remediation of former reactor buildings, recladding of remaining structures and landscaping and other ancillary works.

The former reactor buildings will be enclosed in weather-tight envelope and used as a long-term safestore.

Design coordination

Arup’s scope of work included civilstructural and infrastructure design (including seismic), geotechnics, design of cladding and roof systems, building services, architectural advice and quantity surveying.

The firm acted as lead consultant and design coordinator for the detailed design and site supervision of a new ‘passive’ ILW Store, which will be used to store residual waste recovered during the decommissioning process. 

The store is seismically qualified and designed for a 150-year life. It will accommodate ILW contained in concrete overpacks and liners as well as in drums. It has overhead travelling cranes to store and retrieve items for inspection.