Development of a decommissioning cost model for Australian offshore platforms

Experience has shown that regional factors can contribute to significant variability in decommissioning costs for offshore platforms. Nevertheless, previous studies aimed at estimating decommissioning costs have been valuable inputs for operators, regulators and decommissioning contractors as they develop abandonment and decommissioning strategies and public policy. Estimated costs associated with decommissioning offshore oil and gas platforms in Australia have not been reported widely in the open literature. This paper summarises the physical and regulatory environment in Australia, and develops a cost model which reflects the decommissioning challenges for fixed platforms in this remote region. This cost model could be readily applied to other remote petroleum provinces provided that mobilization times and the nature of the local ocean environment are known. The total cost of decommissioning all 39 current fixed platforms in Australian waters is estimated to be between US$845 and US$1044 million.