Decommissioning and abandonment

Decommissioning and abandonment

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DECOMMISSIONING IN-SITU

DECOMMISSIONING /ABANDONMENT IN-SITU

DECOMMISSIONING / ABANDONMENT IN-SITU ƒ Cleaned, sealed and left in-situ ƒ Do not disturb! ƒ Leave in a safe state ƒ Likely to be the preferred option for: ƒ Pipelines that are already trenched/buried ƒ Trunk lines in North Sea ƒ It may involve the following operations ƒ Cleaning ƒ Product removal ƒ Trenching

Decommissioning or abandonment in-situ is the preferred option for pipelines that are already trenched or buried and North Sea trunk lines. The terms differ in UK and US with ‘abandonment’ being preferred in America. There is less disturbance of the seabed by this method, especially where the seabed takes many decades to repair itself. In the soft seabeds of the Gulf of Mexico, this is less of a concern. There are three main operations for decommissioning in-situ, these are cleaning, product removal and trenching. These operations do not necessarily have to occur in that order.