When an offshore oil rig is outdated or can no longer cost-effectively pump oil, most countries require that they be wholly decommissioned. That process generally includes a requirement that the rigs be physically removed, including the subsea structures—an extremely costly, difficult and dangerous process that potentially has harmful environmental impacts.
It's also a process that scientists at the University of Technology in Sydney, Australia, argue should be avoided. Instead, they claim, it would be both cheaper for oil companies and better for the environment if decommissioned offshore oil rigs were allowed to remain and be transformed into artificial reefs.
In a new paper for the journal Frontiers of Ecology and the Environment published by the Ecological Society of America, three scientists from the University of Technology propose a large-scale expansion of the so-called 'rigs-to-reefs' concept, leaving decommissioned rigs where they stand or moving them elsewhere to create artificial reefs.
Professor David Booth, Dr. Peter Macreadie and Ashley Fowler have formed the Decommissioning Ecology Group to promote consideration of the idea, which Professor Booth took to the national congress of the Australian Petroleum Production and Exploration Association in Perth this week.
"The oil and gas industry worldwide is looking at the decommissioning of 6,500 offshore rigs by 2025," Professor Booth said. "In Australia, more than 60 rigs face decommissioning soon and government policy is still not set. Policy based on science is badly needed in this area.
"A rigs-to-reef project in the Gulf of Mexico dates back to 1979, but most other regions of the US and the world still require complete removal of subsea structures. With mandatory removal targets set to increase, removal and disposal activities will cost the industry billions and would leave a major carbon footprint."
