The acceleration of decommissioning activities in recent times has expedited the need to decommission responsibly and sustainably. Decommissioning activities are increasingly under public scrutiny, yet in many regions there remains a lack of legislation, regulatory guidance, and practical experience in implementing decommissioning activities. In general, the decommissioning process begins with the assessment stage, followed by planning and management, and lastly the actual decommissioning execution. The best practice approach for responsible decommissioning is to conduct a best practicable environmental option (BPEO) study, which is also known as a comparative assessment and/or decommissioning options assessment. The BPEO will identify the most beneficial or least damaging option to be selected for each decommissioning project by accounting for all relevant influencing aspects such as technical, environmental and social impacts, costs, stakeholder opinions, legal compliance as well as health and safety. Such documentation is important to demonstrate that potential impacts arising from decommissioning activities have either been removed or are reduced to as low as reasonably practicable (ALARP). The best decommissioning option will vary depending on local aspects such as environmental baseline conditions, key stakeholders, waste management and disposal facilities, available technologies and the viability of all options considered including reuse (e.g. rigs to reef). This paper outlines recommended approaches for successful decommissioning planning, highlighting key environmental considerations and other important influencing factors. The aim is to demonstrate the importance of holistic thinking for the development of decommissioning strategies to establish a robust decommissioning plan and successful execution.
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