Upon receiving an application for a carbon dioxide storage permit, the North Sea Transition Authority (NSTA) is required by law to ensure (amongst other requirements) that the storage complex and surrounding area have been sufficiently characterised and assessed to ensure there is no significant risk of leakage, or of harm to the environment or human health. As part of the storage permit application, the operator will be required to set out a monitoring plan to demonstrate conformance and containment, detection, and measurement of a significant irregularity or leakage event.

The Government recognise the potential for significant impact of underwater noise from unexploded ordnance (UXO) clearance on vulnerable marine species and is taking active steps to manage and reduce the risk. Two phases of a Department for Business, Energy and Industrial Strategy (BEIS) funded project to characterise and contrast the acoustic fields generated by UXO clearance using high order detonation and using low-order deflagration have been completed and reported on.

It is our understanding that there is no appreciable distinction between the deflagration technique used by commercial and military clearance of marine UXO.

A third phase has now been initiated to further improve the information base, allowing further assessment of the clearance options. A potential 4th phase of the work involving offshore field work is also being actively explored in which comparative noise measurements would be made during actual UXO clearance campaigns using both deflagration and high order detonations. This would require cooperation and active support from industry (windfarm developers) and the regulatory authorities.

The outcomes from the 3^rd and 4^th phases would allow an informed discussion and consideration of the adequacy of evidence by regulatory authorities and the Statutory Nature Conservation Bodies.

The Government recognise the potential for significant impact of underwater noise from unexploded ordnance (UXO) clearance on vulnerable marine species and is taking active steps to manage and reduce the risk. Two phases of a Department for Business, Energy and Industrial Strategy (BEIS) funded project to characterize and contrast the acoustic fields generated by UXO clearance using high order detonation and using low-order deflagration have been completed and reported on.

A third phase has now been initiated to further improve the information base, allowing further assessment of the clearance options. A potential 4th phase of the work involving offshore field work is also being actively explored in which comparative noise measurements would be made during actual UXO clearance campaigns using both deflagration and high order detonations. This would require cooperation and active support from industry (windfarm developers) and the regulatory authorities.

The outcomes from the 3^rd and 4^th phases would allow an informed discussion and consideration of the adequacy of evidence by regulatory authorities and the statutory nature conservation bodies (SNCBs). It will be for the regulatory authorities and the SNCBs to consider the best available scientific evidence when providing advice on these matters.