NjordIC, the specialised global consultancy company for all UXO related topics, has provided Eneco with lifetime ALARP certification for the operational ‘Prinses Amaliawindpark’ in the Dutch sector of the North Sea.
The personnel within the team provided by NjordIC utilised their diverse skill sets, experience, and knowledge to fully assess several various historical and subsea data sets to evaluate, optimise and identify the requirements for ALARP sign-off. This ultimately resulted in ALARP certification for the entire wind farm for the remainder of its design lifetime, with only a few so-called avoidance areas surrounding potential UXO.
In 1991 the Vindeby wind farm in Denmark was the world’s first Offshore Wind Farm (OWF). Since then, many OWFs have been constructed. The majority of which are situated in European waters. These waters were the theatre of many events of war during both World Wars. This resulted in extensive contamination with Unexploded Ordnances (UXOs). Post-war military activities and munition dumping were all contributing factors to this contamination.
Unlike the UXO Risk Mitigations Strategies currently applied when constructing OWFs, several projects were installed before the UXO related threats were correctly addressed. It was not until approximately 2005 that UXO risk mitigation became a more common practice. Nowadays, many employers and regulators worldwide require UXO safety risks to be lowered to levels that are As Low As Reasonably Practicable (ALARP). This also applies to asset management and decommissioning operations for operational offshore wind farms.
A bespoke solution is required for UXO ALARP sign-off for asset management and decommissioning in specific operational OWFs. The major challenge is the presence of turbines, inter-array cables, offshore platforms, scour protection, and export cables. This renders the ‘industry standard’ magnetometer solution, using G882 gradiometers unsuitable. Large areas will lie within the magnetic masking zones of these wind farm components. Furthermore, the utilization of Remote Operated Towed Vehicles (ROTV) with a large array of sensors will be quite challenging – if permitted at all.
NjordIC can provide a tailored approach resulting in lifetime ALARP certification to wind farm owners.