Camera inspection and SONAR development

Project

SPP1 camera inspection and SONAR development

Benefits

SONAR has provided the ability to determine the volume and profile of sludge remotely and reliably, whilst camera inspections have provided the necessary data to validate the SONAR results and improve the extrapolation techniques. The camera system cost approximately £12,000 (+~£5,000 per camera inspection) which has provided significant return on the investment to validate the SONAR system in SPP1, which cost in the region of £2–3 million.

Current Status

The work is ongoing – SONAR scans take place every 6 months and camera inspections are performed on an ad hoc basis as required.

Delivery Partners

Fortis Remote Technology, NNL

Contact Details

Kieran Burke

innovation.team@sellafieldsites.com

SPP1 has three Buffer Storage Vessels (BSVs) which are currently receiving and buffer storing sludge from FGMSP. There is a need to understand the sludge characteristics and volume uptake within SPP1. SONAR equipment installed within each BSV is used to determine the settled sludge profile and total volume taken up by sludge. However, the SONAR has limited coverage within each BSV due to the limited number of SONAR devices and shadowing caused by internal furniture. When shadowing occurs, extrapolation between datapoints is used to fill in the gaps. Furthermore, it was also uncertain how accurate the SONAR measurements were in areas with good coverage.

Camera inspections were proposed to provide visual confirmation of the settled sludge bed relative to known items within the BSVs. These images can be compared against the SONAR measurements to determine its accuracy. The NNL camera inspection team carried out camera inspections in SPP1 utilising maintenance ports within the BSVs. This work has resulted in the validation of SONAR measurements in well-covered regions and provided insight into those with poor SONAR coverage. Consequently, it has enhanced comprehension of sludge profiles in these regions, as well as understanding the accuracy and limitations of SONAR extrapolation techniques.

SONAR scans and camera inspections will continue to take place periodically as SPP1 continues to fill with sludge and operations are conducted to flush equipment that is submerged by sludge.