Offshore staff
OSLO, Norway --Total expects to complete removal and disposal of the abandoned Frigg field sea lines in the North Sea in 2008.
This year, Sonsub has implemented engineering and procedures to remove 17 km of pipelines, cables, and flexible pipes weighing a total of around 4,000 metric tons (4,409 tons). Their diameters range from 1-26-in. (2.54-66 cm).
Excavation and pipe cutting operations started this May. Sonsub has deployed a device known as a mass flow excavator, comprising a "bucket" with an inbuilt propeller. This generates a flow of water that dislodges protective rocks around the pipelines.
Total expects nearly half the sea lines removal work to be conducted next year. Sonsub has loaded the cut pipe sections into bundles on the seabed. Each bundle will be lifted to the surface and transported to Stord, Norway, for disposal. Sonsub also will recover and ship to Stord remaining pipeline protection mattresses, concrete saddles, blocks, and grout bags.
Flexible pipes and cables will be reeled onboard the decommissioning vessel using the reverse lay method. Finally, Total will commission a trawl test from a fishing boat over the surrounding 500 m (1,640 ft) zone to ensure the field is usable as a fishing area in future.
11/05/2007
