Erika pumping operations completedNews // October 5, 2000
CSO Constructor, the last vessel in the consortium to work on the two sections of the wreck, completed work after the removal by divers of all subsea structures associated with the pumping operations, which took place in 125m of water.
The contract was awarded last April to a consortium formed by CSO International and Stolt Offshore. It called for recovery and neutralisation of heavy fuel oil remaining in the two sections of the wreck, which are located about 10km apart.
The work was broken down into three main phases. The first, in June, saw the survey of the wreck sections undertaken by a Triton(r) XL remotely operated vehicle (ROV) and the preparation by divers of the two sections of the wreck for pumping operations,including drilling of the hull, and installation of valves to recover the fuel safely.
Between July and September, pumping operations were instigated, using a process developed by and under the direction of TotalFinaElf. Once all of the fuel oil had been removed, two sites were decommissioned.
In order to complete the operation, the Consortium led by CSO mobilised a team of nearly 40 people onshore and 300 workers offshore split between seven vessels (CSO Constructor, Seaway Kestrel, Crystal Ocean, British Shield, Anglian Duke, Melide and Zeus).
More than 30,000 hours of saturation diving were required using the dynamically positioned construction vessels (CSO Constructor and Seaway Kestrel), of which 9,600 hours were actually spent under water on the two sections of the wreck. The work performedby the divers included drilling the hull and installing 64 valves to recover the cargo, and the installation and recovery of the pumping system.