Decommissioning and abandonment

36

Decommissioning and abandonment

FLEXIBLES

ƒ Re-use of flexibles

ƒ Common offshore Brazil ƒ End lifted and re-reeled ƒ Cleaned, inspected and overhauled prior to re- use ƒ End fittings usually replaced ƒ Australian QA / insurance recertification concerns

Any damage tends to occur near the end fittings so that is why these are replaced. The whole length is fully inspected and any repairs carried out. Brazil has a stockpile of flexibles, stored in a lake (out of sunlight), that are ready for reuse. Nevertheless, in Australia, reused flexibles cannot get insurance.

BUNDLES

BUNDLES

ƒ Bundle dewatered ƒ Some chains released by ROV or diver ƒ Towed to new location using off-bottom method ƒ Reflooded and weight mattresses added ƒ Goosander field, north of Kittiwake ƒ Installed by Subsea 7 for Venture ƒ Reusable bundle 12.3 km (7½ miles) in two lengths ƒ Production flowline, water injection, gas lift with chemical injection and control lines

There is the possibility of a bundle being reused. However, this would require a very similar configuration (both length and flowline cross-section) for the second field. It would need to be refloated by purging the flowlines with gas. The annulus could be dewatered using a gel slug, which could pass the pipeline spacers.