Providing UXO Consultancy for East Anglia ONE Offshore Wind Farm

Scottish Power Renewables (SPR) has just completed the construction of the East Anglia ONE (EA1) offshore wind farm, which covers an area of approximately 300 km². With 714 MW of installed capacity and 102 wind turbines, it is one of the biggest offshore wind farms in the world.

Prior to and during construction, Tetra Tech worked with SPR providing independent UXO consultancy. This included site specific risk analysis and strategy design followed by geophysical survey and data quality assurance/quality control (QA/QC), processing and interpretation. Based on the geophysical data Tetra Tech identified potential UXO targets for further investigation and oversaw the entire investigation process which culminated with the disposal of nearly 100 items of UXO including WWII bombs and sea mines.

The schedule to complete the UXO mitigation prior to construction starting was always tight. If the UXO risk wasn’t signed off by Tetra Tech in time, it could have caused significant delays for the project, including vessels going on standby.

Tetra Tech provided pragmatic solutions to minimise risk, whilst keeping the project on schedule. The team worked closely with SPR to ensure that deadlines weren’t missed and were able to provide individual risk sign off certificates for each turbine in time and sometimes immediately prior to the vessel arriving.

Ultimately the UXO mitigation was all completed successfully to allow construction of the wind farm which is now complete with no UXO related delays or incidents.