Salvage of Capsized Rig to Finish by March 2015

Salvage work to remove a capsized rig lying in shallow waters offshore from Angola's new liquefied natural gas (LNG) export plant should be completed by March 2015, the company in charge of the operation said.

The three-legged Perro Negro 6 drilling rig overturned last summer as it was being positioned to bore a tunnel for a gas pipeline key to feeding the $10 billion plant.

Italian oil services firm Saipem chose South African company Smit Salvage, a unit of Netherlands-based dredging specialist Boskalis, to remove its rig.

"Including the preparation phase (engineering and outfitting), mobilization and demobilization, the salvage operation is expected to take around 10 months," a Boskalis spokesman said. "The work is expected to commence in this quarter."

The rig capsized as it prepared to bore a tunnel below an underwater canyon, killing at least one person and delaying gas supplies from Chevron-operated blocks 0 and 14, which were to be linked to the plant this year via the tunnel.

It will take even longer for a new rig to come into position and dig out a tunnel for the pipeline, a source linked to the liquefaction plant said.

Feedgas from the Chevron blocks is essential to helping Angola LNG boost production, which has only managed to reach 50 percent of capacity despite starting up nearly a year ago.

Fresh technical setbacks have recently forced the plant to shutdown as engineers investigate the cause of malfunctions.

Chevron has a 36.4 percent share in the plant, while Angolan state oil firm Sonangol has 22.8 percent. Other stakeholders include Total, BP and ENI.

Photographs of the Perro Negro 6, seen by Reuters, show it lying sideways, half-submerged in the Atlantic.

(By Oleg Vukmanovic, Editing by Mark Heinrich)