Abstract

Chemical dispersants for combatting oil spills increasingly are being recognized as a most valuable addition to the available means for damage prevention and cleanup. In high seas and for large spills, only dispersants are capable of being used effectively. In less stressful circumstances there may be a choice between use of conventional (i.e., mechanical) methods, such as booms and skimmers, and dispersants. Then the decision of which, if not both, to employ, should be made based on, first, what method will best prevent or minimize damage to resources as well as promote the most rapid recovery of impacted ecosystems, and second, what are the anticipated relative costs of mechanical versus chemical methods. Protection of mangroves from oil spills is important in Indonesia and recent research shows that dispersing oil slicks is effective in preventing tree injury and death.

These considerations are important for Indonesia because of the necessity for being able to respond to a large oil spill in Indonesian waters, and the organization by major oil companies including Caltex of one of the world's largest oil spill cleanup cooperatives, based in Singapore. By use of a four engine dispersant spraying aircraft, a 600 mile radius from base including Malacca Strait will be protected.

A study of oil spill cleanup costs provides a most useful perspective. Based on public information sources where costs were reported for cleanup of oil that impacted a shoreline, mechanical methods cost from a minimum of $65 per barrel of oil to as much as $5,000 per barrel. In contrast, costs for intercepting the oil at sea by spraying dispersant from four engine aircraft ranged from $15 to $60 per barrel of oil treated.