First containers sealed into Dounreay low level waste vaults

As part of the waste disposal process, the spaces between the containers in the low level waste vault are being filled with grout.

The team undertook a series of trials to confirm that the grout would readily flow between the containers and also tested the membranes that will be used to seal the grout shutters.

A first campaign of grouting has now been completed within the vault and 16 waste packages have been sealed into their final positions. Further grouting campaigns of increasing size are planned.

In parallel with this work, the external space around the outside of the walls of the vault has been backfill filled with aggregate. In the first phase of this work, enough aggregate to fill an Olympic sized swimming pool has been used to fill up to 2.5m high around the structure. This is only 2% of the total volume of material that will be needed to backfill, cap and close the 2 vaults once they are full.

Project Manager Graeme Morgan said:

This work is a strategically important demonstration that we can carry out this crucial part of the disposal process, which will eventually enable us to close the vault.

Senior Engineer Angus Mackay added:

We’ve had a fantastic level of support from so many people across the site and the quality of the workmanship has been superb. It’s great to see the disposal process moving forward.

The work has been completed by a team from Dounreay Site Restoration Ltd along with local contractors Arch Henderson, John Gunn & Sons, JGC Engineering and Hugh Simpson Contractors.