The Magazine for Underwater Professionals
Divers have located around 40 pieces of debris around the site at Dalmore Bay, on the Isle of Lewis, Scotland, where the Transocean Winner drilling rig originally grounded in bad weather on 8 August. The debris ranges from laptop size to a 1.5 tonne thruster.
Divers have been recovering the broken parts by hand, but a crane is to be used to recover the thruster, which detached from a leg of Transocean Winner during the grounding.
Deputy Secretary of State’s Representative Maritime Salvage and Intervention, Colin Mulvana, said the divers had been working very hard to make sure that they were picking up all the bits found on site, but there may well be previously undetected debris that may appear following bad weather.
A future programme of surveys will be discussed and put in place by Transocean in an effort to ensure the area is clear of debris and safe for members of the public, he said.
The Transocean Winner was being towed from Norway to Malta from where it was to be moved to a yard in Turkey to be broken up. A tow line between the rig and a tug broke during stormy weather and the structure ran aground.
The 17,000-tonne Transocean Winner has now been towed to Broad Bay. Norwegian firm Offshore Heavy Transport (OHT) is expected to float the rig onto the semi-submersible heavy lift vessel OHT Hawk in late September and transport it to Turkey.
Dutch contractor Allseas’ dynamically positioned single-lift installation/decommissioning and pipelay vessel Pioneering Spirit has successfully executed its maiden heavy lift project, the removal of the 13500-tonne Yme mobile offshore production unit (MOPU) in the North Sea, 100 kilometres off the coast of Norway. The project was undertaken on behalf of Repsol Norge.
The Yme MOPU is a jack-up type platform standing on three steel legs of 3.5-metre diameter, which are inserted approximately 10 metres inside the subsea storage tank columns at 93 metres water depth.
“With this platform removal, Allseas was able to demonstrate the unique single-lift capabilities of Pioneering Spirit,” the company said.