Managing the Sellafield trenches

Cleaning up the Sellafield site and dealing with the historical nuclear legacy involves tackling some complex issues and one particular issue that has been addressed recently is the management of the Windscale Trenches.

The Windscale Trenches were unlined excavations used by the Windscale Plant in the 1950s to bury lower level wastes and some items too large for intermediate level waste stores.

Although the trenches were accepted practice in their day, their impact on the environment is a potential concern. A two day workshop involving key local stakeholders, the Environment Agency and the Office for Nuclear Regulation (ONR) took place at the end of last year to agree on the Best Available Techniques (BAT) for controlling the contents of the trenches until final remediation takes place to meet the end state for the site.

Julian Cruickshank, senior technical leader Land Quality, said: “The group accepted that the hazard posed by the trenches is small, but we must demonstrate that the management of the trenches meets Site Licence conditions and that best practice is being followed. The consensus was to bring the entire area up to the enhanced standard of capping previously installed over approximately half the trench area.”

Ron Hargreaves, from the West Cumbria Site Stakeholder Group, said: “I was impressed by the wide range of inputs and the open discussion. It rapidly became obvious that the hazard posed from these trenches is small compared to some other facilities on site and that the risk posed to the environment is close to zero.”

“In my view the workshop demonstrated the very thorough examination of this topic and a strong desire by Sellafield Ltd to explore all avenues for action”.

This outcome is a very positive one for the development of the Land Quality strategy on the Sellafield site and could result in the deferment of significant spend.