On the 9th of November the Swamp Barge 'Raissa' was performing drilling operations for TOTAL E&P Indonesia in the TUNU 13B Field, north of Balikpapan. During the drilling operation a shallow gas pocket was hit, resulting in a gas blowout and this led to the partial collapse of the seabed. The rig then suffered a severe stern trim and portside list.
SMIT Salvage was contracted to recover the derrick and refloat the Raissa. Firstly, the 1,000Mt sheerlegs SMIT Cyclone was used to recover both the derrick and pipes. To refloat the Raissa, a combination of air pressurizing, pumping and lifting was used.
Firstly, all the flooded tanks were pumped dry and pressurized to create buoyancy, after which the SMIT Cyclone was connected at the stern for additional lifting force and to counteract any unforeseen environmental changes and/or free surface effects during the refloat operation. The Raissa was refloated and stabilized successfully and could continue its drilling operation once repaired.