Vaulting ambition realised in UK industry first Dounreay Low Level Waste Facility

An essential element in the largest nuclear site closure in Europe, the D3100 Dounreay Low Level Waste Facility project was a UK industry first for the disposal of low level nuclear waste – incorporating the first purpose-built venue of its kind. Completed on time over 32-months, and on budget to a value of £14m, we excavated a total of 243,000m3of rock during the construction of two below ground concrete vaults – each with a volume equivalent to between 370 and 450 double-decker buses.

The focus of national media scrutiny, the high-profile D3100 Dounreay Low Level Waste Facility was constructed to protect future generations from any harmful effects associated with low level waste. Facilitating the safe disposal of up to 175,000m3 of the by-product, the £14m scheme centred on the design and construction of two sub-surface, reinforced concrete vaults.

Incredibly, vault excavation required over 70 tonnes of explosives. Slope stability and maintenance was provided using inclined rock anchors and rockfall mesh, while drainage systems and a water treatment area were developed as innovative solutions to deal with non-radioactive liquid discharges.

Infrastructure works, inclusive of access roads and perimeter security fencing, were additional strands of this Gold Award winning Considerate Constructors Scheme site.

In total, 7600m3 of concrete, 1330 tonnes of reinforcement and 260 tonnes of structural steel were manipulated in the creation of each vault. May 2014 marked the handover of the two vaults – this milestone achievement subsequently triggered a £300,000 payment by the NDA to good causes in Caithness.