As the offshore energy industry expands it is important that developers take account of and address the risks of unexploded ordnance (UXO) in the marine environment.
Subsea World News recently spoke to Adrian Dann, a man who heads up James Fisher Subsea UXO services.
He is ex-navy senior personnel who specialises in the identification, removal and detonation of UXOs and EODs.
James Fisher Subsea was formed in 2015, bringing together the James Fisher and Sons air/nitrox diving, dive equipment, ROV, subsea survey assets and operations under one roof.
In our interview we asked Mr. Dann to bring us closer to JF Subsea’s UXO removal, and how the company addresses the safety of both its personnel and equipment during these kind of operations.
Considering your experience in the navy, could you tell us what you bring to JF Subsea’s UXO detection and detonation operations and what are your responsibilities?
I have had some 26 years’ experience in the Royal Navy as an EOD officer and mine-clearance diver, so I bring with me a well drilled and safety orientated mentality that ensures all our UXO operations at JF Subsea are inherently safe. It’s my responsibility to vet all the personnel involved in a JF Subsea UXO operation and generally I ensure they come from the same background and share the same professional qualifications.
I also bring some unique equipment to the company that innovate UXO operations, as I’m the owner and designer of the Barracuda bomb and mine disposal system, which has so far successfully disposed over 36 live items for JF Subsea in support of the offshore industries. In total since 2008, the Barracuda has disposed of 457 live items of UXO on 3 different continents.
We’ve seen several European offshore wind projects experiencing costly delays relating to mismanagement of UXO risks especially during construction, what are the most important aspects of conducting UXO identification, removal and detonation projects?
The most important factor obviously, overall, is the safety, and the whole operation is conducted under a very strict method statement and with very strict safety precautions in place.
Could you take us through one of your UXO disposal campaigns, how it’s done and what safety measures do you take?
The identification is done by the JF Subsea team with me taking lead using the experience gained primarily from the Royal Navy during operations, and we ensure that the safety of the whole team is maximized by using ROVs as a standard procedure. We only use mine-clearance divers in very shallow water where we know that the potential risk to the diver, presented by the identified UXO, is very low.
Whether the evaluation is conducted remotely or by divers, we always have a ‘no-touch philosophy’ and means simply at no time will an ROV, diver or a disruptor (the Barracuda, which we place), touch the item that is being prosecuted. This key procedure ensures the maximum safety for both the operational assets and especially the people who are operating the equipment.
Which areas have you witnessed having the highest number of unexploded ordnance left behind on the seabed by two World Wars, considering that offshore energy industry continues to expand in UK and European waters and managing UXOs is of high importance from the early construction phases into a prolonged period of operations and maintenance?
It is a close call, very close call between the Baltic Sea and the North Sea. I would say on balance that North Sea has probably got the largest entity, but of course we haven’t included the Middle East, which is a growing area and something we’re looking to target.
Protecting the environment is very important. How does JF Subsea mitigate the impact to sea life during these operations?
Prior to any detonation, be it small or large, exactly the same environmental procedures and equipment are deployed. We always deploy an ADD-acoustic deterrent device, which uses sound to warn marine life in order to keep them away from the operational site. We also deploy a passive acoustic monitoring system (PAMs), which is another audible device, which the team use to observe the area and can listen for citations, harbour porpoises and mammals to identify if any marine life is in the vicinity.
We also fire two small 250g fish-scaring charges (the size of a sausage) 30 minutes and 10 minutes prior to detonation, which gives the fish in the area a warning that they might want to disappear. In German waters, we have also recently deployed a full ring bubble curtain, which acts to suppress the noise. Sometimes we also provide blast monitoring, which is a small centre that we can put 100 meters away from the blast which will record the peak, what we call ‘the bubble pulse’ which is the peak pressure of the top of the explosion so at the highest point of the pressure wave it will record that and then we can download that afterwards to establish exactly what the magnitude of the explosion was.
We also do a very thorough as-found survey with the multi-beam echosounder which will give us a 3D image of the location of the UXO and the seafloor on which it sits, and we do an as-left survey where we also do a mutli-beam echosounder trace to establish the extent of the depth and the size of the resultant crater following a detonation.
Safety is absolutely paramount, that is on top of our agenda. We have not had one single accident or incident in the 457 live firings we’ve done since 2009.
Set up in 2015 to combine James Fisher’s subsea capabilities, what do you think sets JF Subsea apart from other contractors who have also ventured into this competitive market due to slowdown in the oil & gas industry?
We’ve got an excellent safety record and an excellent track record of delivery, where we can demonstrate our live disposals to an absolute number, all of which can be cross-referenced to the jobs that we’ve undertaken. We use first class ex-military operators who are at the top of their game, and as a team we maintain levels of training to ensure that all of the operators are up to speed.
JF Subsea also has all the assets required to deliver an integrated solution from the initial survey to the identification and risk assessment. This includes a first-class diving and ROV spreads and operators that have delivered large scale projects, worldwide in the renewable and oil and gas markets, so we’ve got a good list of credentials to provide the turnkey service to the UXO problem.