Decommissioning Challenges in Thailand

Thailand's oil and gas industry has been successful in finding and recovering hydrocarbon reserves in the Gulf of Thailand since last three decades and have currently installed over 200 fixed offshore structures. Some of these installations are now reaching the end of their economic productive lives and will need to be decommissioned soon. There are complex issues in terms of legislation, environment, safety, costs, technical feasibility and public acceptability. This paper describes the issues relevant to decommissioning in Thailand and proposes appropriate decommissioning solutions developed over the past few years. The proposed decommissioning solutions are intended to support Thailand's oil and gas industry and its regulators in ensuring compliance with international decommissioning guidelines, balancing economics, safety, practicality and technical feasibility of operations with the environmental benefits and also satisfying needs of the key decommissioning stakeholders in Thailand so as to achieve conflict-free process of decommissioning. Technical aspects of offshore removal process primarily relates to the lifting of modules and sub-sea structural cutting methods. Lifting techniques range from conventional crane barges used in installation to specialized decommissioning vessels. Basically cost, technical feasibility and safety are major drivers in selection of appropriate lifting method. Sub-sea cutting include explosives and cold cutting techniques, for which cost and environment are the major decision making factors. Environmental aspects of decommissioning can be categorized into short term and long term. Short term environmental impacts are primarily related to the decommissioning methodology whereas the long term environmental impacts are related to the chosen disposal scenario i.e., final destination of each component of an offshore facility. Key recommendations regarding environmental solutions are in the form of Best Practicable Environmental Option (BPEO) framework, which helps determining balanced disposal scenario as well as suitable decommissioning methodology. Increased energy demands have currently resulted in rapid growth of number of offshore installations in the Gulf of Thailand. At the same time, the old disused installations need to be timely and appropriately decommissioned, which is not possible without having acceptable decommissioning solutions in hand. Such solutions need to be in compliance with applicable international decommissioning guidelines while adopting best practical environmental option hence assuring conflict-free decommissioning process. Therefore, development of such decommissioning solution are significant in assuring "RESPONSIBLE PERFORMANCE: TO DO THE BEST WE CAN" in order to help attain sustainable benefits for further development of Thailand's oil and gas industry.