Phase Two of Debris Recovery Operations Well Underway
Ongoing debris recovery operations are well under way at the Astrolabe Reef (Otaiti). As well as the large hydraulic ‘orange peel’ grab, a powerful electro-magnet is now being used to recover smaller metallic cargo and debris, including lighter hull plate sections.
Roger King of TMC Marine Consultants says that after an initial settling-in period, the magnet has achieved what salvors hoped in removing a lot of debris that the grab could not get.
“It doesn’t get the large volumes, as the hydraulic grab does, but it does get ferrous material from around the rocks that the grab can’t reach,” says King.
“The salvors like working with it as the crane driver can pick debris with little effort and the riggers on deck like it as it only gets the ferrous scrap and debris, which means less time sorting non-metallic materials, but importantly less potential for damage to the reef,” King says.
“The thousands of steel balls we’re recovering are a case in point – it would have been impossible without the magnet.”
Unsettled weather has hampered recovery efforts in recent weeks and even when salvors do get out on the water, the rate of recovery has reduced considerably as many of the areas where they could access large deposits of debris have now been covered.
An additional 228 tonnes of debris has been recovered during the latest operation, taking the total amount of debris recovered to more than 1,820 tonnes. A further 150-plus tonnes is presently on board the RMG1000 barge. Recovered debris has included significant quantities of container parts, scrap cargo, aluminium ingots, tyres, fibreboard and smaller quantities of wire.
Operations have also involved dive teams to aid in cutting hull and bow structures for removal from shallow waters, which previously restricted the salvors’ access to debris.
The following images are from phases one and phase two of the operation showing the hydraulic crane grab and magnet in action, as well as the types of debris recovered. A third and final stage will involve diver teams to recover smaller items. An estimation of the debris remaining in the field is presently underway.