• Australia
  • Oceania
  • Asia-Pacific
Case Study

Pipeline Decommissioning

PROJECT SCOPE OF WORK

Chevron Thailand under their Asset Retirement obligations was required remove subsea pipeline tie-in spools in sections and recover the spool sections in preparation to get ready for the pipeline removal campaign. Also planned for removal in the same field were the remaining elements of the Tantawan production system. Activities under this scope included:

Part I

77 instances of Tie in spool disconnection and associate subsea valves operations. Pipeline, removal by cold cutting subsea, plugging ends and retrieving to deck for any required marine growth cleaning, and then discharge of contained/contaminated

water within plugged pipeline section.

Part II

SPM I and II Decommissioning.

Part III

Removal of Tantawan PLEM

 

 

 

PROJECT SUMMARY

The work was completed a little ahead of client estimations. The project was notable for its length of time and the performance of the Fire Opal with very little downtime over the entirety of the project. Also notable was the excellent HSE statistics given the nature of decommissioning which requires extensive unplanned work arounds, re-engineering and MOCs as most of the subsea production system was decades old and sometimes as found surveys did not match planned  drawings.

An outstanding job by the Dive team in the conditions.