A pioneering new technique to remove sludge from nuclear fuel ponds has been successfully trialled at one of the UK’s largest wet test facilities.

The Decommissioning Alliance (TDA) is tasked with installing equipment to allow operators to safely retrieve debris laying at the bottom of fuel ponds at a site operated by the Nuclear Decommissioning Authority (NDA) in order to safely remove and transport the recovered material for safe, long-term storage.

TDA representatives will complete the task by attaching a Bulk Sludge Retrieval Tool (BSRT), which ultimately acts like an industrial hoover, to a 40-metre Umbilical. The tool will retrieve the sludge and then store it in a safe manner.

To test the new way of working, which includes the use of remotely operated vehicles to lock a hinged double boom arm in position, the team trialled the methods at engineering specialists Forth’s Deep Recovery Facility (DRF) in the company’s headquarters at Flimby, in Cumbria.

Instrumental in reducing inventory in the pond

TDA project manager Scott Bond said: “The work we are carrying out at the site has been ongoing since 2010 and has been instrumental in reducing the inventory in the pond, which in turn reduces the overall risk.

“We are always looking for ways to ensure our work is safer, more efficient and more cost effective for the client, and the new methodology of installing the BSRT and the umbilical has the potential to be a game changer.

“Before implementing the practices live on-site, we need to be 100% certain that they are safe and effective, so the trials we carry out are absolutely essential.

“Being able to successfully test the equipment at Forth’s DRF, particularly when it’s on our doorstep, was a Godsend for the project because we couldn’t find a facility big enough to host the trials; other than the open sea or a dock, but that brings with it more hindrances as the water is very corrosive.

“Using the excellent indoor facility meant we were able to successfully trial the methods and replicate site conditions on more than one occasion, ensuring the TDA installation team are familiar with the equipment, tooling and installation sequence, when the time comes to putting the learning into live action.”

Largest of its kind in the north of England

Able to hold 1.2 million litres of water as it measures 22.5 metres long, 10 metres wide and six metres deep, the DRF at Forth is the largest of its kind in the north of England.

To facilitate the tests, engineers at Forth designed and manufactured a frame to attach the equipment, and they provided access scaffolding and operators to deploy the equipment.

Graham Cartwright, the projects director at Forth, said: “It’s been great to be able to play a part in what is such a major development for the nuclear industry.

“Our DRF has time and again proved vital in providing wet testing for key projects and being in a position to facilitate these trials has been something we are really pleased with.”

More details about the Deep Recovery Facility at Forth is available at info@forth.uk.com.