Oil Spills

Petroleum is a critically important natural resource. However, petroleum is often mined in places that are far away from the regions where most of its consumption occurs. Accordingly, petroleum must therefore be transported in large quantities, mostly by oceanic tankers, barges on inland waters, and both subsea and overland pipelines. Any of these transportation systems can release pollution through accidental spills of oil, by operational discharges associated with cleaning of the storage tanks of tankers, or during unloading at refineries. Some accidental oil spills have been spectacular in their magnitude and their near-term ecological impact, involving losses of huge quantities of petroleum from wrecked supertankers or offshore platform facilities.

In addition, oil pollution is caused by discharges of improperly handled hydrocarbon-laden waste water from petroleum refineries and in urban runoff. Although each of these spills typically involves relatively small quantities of material, the spills occur rather frequently, so in total, large amounts of oil are spilled in this way.