Technical Guidelines on Recommendation of Guidelines to Enhance the Safety of Decommissioning Process within the Southeast Asia Regions

Abstract

The guidelines focus on decommissioning activities concerning oil and gas fixed offshore structures in the Southeast Asia region. It is recommended in compliance with relevant international conventions, national regulations, and regional guidelines governing decommissioning activities. Its focus is specifically on identifying risks and mitigating them during the removal process of fixed offshore structures in offshore decommissioning. The guidelines address three removal options for fixed offshore structures: Complete removal, partial removal, and leave in situ. Total removal involves the complete dismantling and removal of the offshore structure from its location. This approach requires extensive planning and execution, including cutting and lifting the structure piece by piece. It often involves higher costs and environmental impact due to the complete removal of the structure. Partial removal, on the other hand, entails removing the topside and any other visible components while leaving the substructure in place on the seabed. This option is not as intense as total removing, but it still requires a lot of work and resources. The option is when the topside contains hazardous materials or when there are environmental concerns. Leave in-situ, typically as reefing, means keeping the entire structure or certain parts of it in its current location on the seabed. This approach can serve as a habitat for marine life, and this option is typically more cost-effective than complete removal. However, a thorough assessment of environmental impacts is required, and future use of the area must be considered. The evaluation of these removal options aims to identify key challenges, assess associated risks, and develop effective mitigation plans tailored to each approach. This comprehensive assessment ensures that the chosen decommissioning strategy aligns with safety, environmental, and economic objectives while complying with relevant regulations and guidelines.