Some 200 people are being mobilised for modification work during the turnaround on Statoil's Gullfaks C platform in the North Sea later this year.
Part of the second phase of the group's Gullfaks satellites development, the work will equip this installation to receive gas from Gullfaks South.
The 14-day turnaround is due to start on 15 October and the main job for the satellites team will be to free up space for two large modules, reports project manager Torstein Gabrielsen.
These M10 process and M19 wellstream reception units are currently under construction by Aker McNulty at Newcastle upon Tyne in the UK for installation in the autumn of 2000.
Another 14-day shutdown required by the project next spring on Gullfaks C will be so extensive that a flotel is needed to accommodate the additional workforce.
Between these shutdowns, and right up to the end of the project in 2001, about 80 people are due to pursue integration and hook-up work on the platform.
In addition comes work on Gullfaks A during the turnaround planned for this installation from 1 September. Forty people will be mobilised to free up space for various items of equipment as well as valves and piping.
Continuous modification and installation jobs will also be pursued on the platform during 2000.
"These are intensive and demanding projects, since all work outside the shutdowns must be done without disrupting day-to-day operation," explains Mr Gabrielsen.
"One of our many challenges is to upgrade the flare systems on Gullfaks A and C. Such jobs are very weather-sensitive and call for particularly good planning."
The Gullfaks satellites development comprises Rimfaks and Gullveig as well as Gullfaks South, and is being pursued in two phases.
Phase 1 came on stream last October, when oil began flowing from Gullfaks South to Statfjord A. The second phase primarily covers gas, and is due to start production on 1 October 2001.
This Statoil project is the second largest subsea development off Norway after Åsgard in the Norwegian Sea, which is also operated by the group.