Increasing inspection coverage using ROVs

Project

Highly active buffer storage facility inspection

Benefits

Enhanced condition monitoring of key ageing nuclear asset, providing assurance that the plant is safe to continue operating. The project also provided a proof-of-concept for the successful deployment, use and retrieval of a COTS ROV for remote visual inspections across the HALES facility, thus improving cell coverage without the need for the costly drilling of new inspection ports. The use of COTS equipment also provides a cost saving compared to using bespoke equipment.

Current Status

Initial inspections have been completed successfully. Plan to expand the technique throughout the remainder of the facility.

Delivery Partners

NNL

Contact Details

Matthew Haigh

innovation.team@sellafieldsites.com

The highly active buffer storage tanks store liquid waste in preparation for being processed by the Highly Active Liquor Evaporation and Storage (HALES) facility. They are large tanks enclosed within shielded cells, with very limited access, and have been in operation since the 1950’s. The tanks are subject to a regular remote inspection regime to assess their condition. However, due to the access constraints, the coverage of some assets is limited using the existing inspection technology.

A project was initiated to increase the proportion of vessels inspected. After optioneering, a ROV was determined as the most appropriate solution. A bespoke ROV had been developed with NNL for a separate project in the facility, serving as a proof-of-concept to seek a permanent ROV inspection solution. The requirement was to procure a COTS vehicle to allow rapid replacement in the event of failure or contamination. Equipment which fulfilled the specification was identified and purchased.

The access port to the tanks is approximately 10m above the ground and through a wall, adding additional complexity to the inspection. Therefore, a system to post the ROV through the wall port and lower it to the compound floor was developed. This innovative system allows the COTS equipment to be operated in our unique environment.

In February 2024, the deployment was a resounding success. The ROV was able to gain views of the vessel which have never been seen before, increasing our understanding of the condition of the tank and aid monitoring of the condition as it continues to age.