Underwater Construction Corporation (UCC) UK Ltd recently achieved a significant nuclear power decommissioning milestone for Sellafield Ltd by safely completing a nuclear diving project in its oldest legacy pond, the Pile Fuel Storage Pond (PFSP), located in Cumbria, England. Through the development of specialized processes, equipment, and trials, UCC supported Sellafield’s cleanup goals while maximizing safety and reducing long-term risk during this nuclear power decommissioning mission.
The pile fuel storage pond is the oldest pool on the Sellafield site. The facility was constructed between the late 1940s and early 1950s as a storage and cooling facility for irradiated fuel and isotopes from the two Windscale reactors and was in full operation until 1962. Through the mid-1970s, the pond facility, one of six onsite, was then used for storage of intermediate-level waste and fuel from the UK nuclear program. Today, Sellafield is challenged with cleaning up the legacy of the site’s early operations, including the Pile Fuel Storage Pond, one of Europe’s most hazardous nuclear facilities. UCC and its UK subsidiary’s nuclear divers complement Sellafield’s vision and legacy ponds cleanup mission.
Photo courtesy of Sellafield Ltd.
UCC UK Ltd, in partnership with Sellafield Ltd, spent more than four years developing customized procedures, processes and equipment to optimize safety and working conditions for its nuclear divers while minimizing exposure to radioactive materials. Dive trials were conducted in an offsite facility that closely mimicked the Sellafield Pile Fuel Storage Pond, utilizing specially developed dive platforms, CCTV monitoring, diver manipulated long reach tooling, cutting equipment, and radiation monitoring equipment.
In December 2022, UCC UK Ltd became the first nuclear diving company in more than 60 years to enter the Pile Fuel Storage Pond. According to Sellafield Ltd and the Nuclear Decommissioning Authority (NDA), “the last time a human entered Sellafield’s Pile Fuel Storage Pond was in 1958 when records show a maintenance operator and health physics monitor carried out a dive into the newly constructed pond to repair a broken winch.”
Utilizing experienced nuclear divers complemented previous practical pond work using Remotely Operated Vehicles (ROVs) and other specialty bespoke remotely deployed tooling. The rigorously monitored work allows the diver to be close to the work, which ultimately reduces schedule time and, in turn, reduces the risk quicker, and with shorter schedules come reduced long-term costs for the customer.
“Since the 1970s, our nuclear diving experience has shown that the safe use of divers lowers overall program radiation exposure, reduces overall schedule and cost, and is regulator endorsed, proven, and repeatable,” said Philip McDermott, Chief Operating Officer, UCC UK Ltd. “I congratulate our team of nuclear divers and supervisors, as well as the collective effort of everyone involved in this project, for successfully developing this highly specialized solution to support Sellafield Ltd’s nuclear decommissioning efforts. The pilot has proven that nuclear diving is a beneficial addition to the waste retrievals program within the ponds.”
Photo courtesy of Sellafield Ltd.
“The success of the Pile Fuel Storage Pond (PFSP) diver project is a significant milestone for Sellafield. It’s a testament to the skill and expertise of both Sellafield and UCC UK Ltd and demonstrates how we use innovation to help us solve some of our most complex and challenging problems,” said Carl Carruthers, Head of Programme Delivery for Legacy Ponds, Sellafield Ltd. “Safety, security, and sustainability are at the heart of what we do and who we are. Collaborating with UCC UK Ltd has helped us make real progress in cleaning up the PFSP and will help us deliver our mission of creating a clean and safe environment for future generations.”
“UCC and our UK subsidiary are proud to support the Nuclear Decommissioning Authority’s (NDA) long-term and vital mission to safely and efficiently clean up the UK’s legacy nuclear ponds. We offer proven, unique, innovative, and high-tech solutions to the NDA’s Integrated Waste Management program, specifically with retrievals, volume reduction, and underwater packaging,” McDermott said. “We look forward to supporting other global customers in the nuclear decommissioning industry with our proven, safe, reliable underwater solutions.”
For more nuclear power decommissioning project details and to hear from various project members, view this video, courtesy of Sellafield Ltd.
About UCC UK Ltd
Underwater Construction Corporation began its wholly owned UK subsidiary in 2015 to deliver safe and economical underwater solutions to the Nuclear Decommissioning Authority (NDA) site license companies, such as Magnox, Dounreay, and Sellafield.