Source Control

Source control is the response priority of stopping or limiting a pollutant at its origin before it disperses. In a spill it means securing the leak: closing valves, transferring cargo, plugging a hull breach, or, for a subsea blowout, capping the well or installing a containment dome. Deepwater Horizon flowed for 87 days, releasing about 4.9 million barrels, because source control at the wellhead took that long; the capping stack that finally sealed it became a standard subsea-well-control tool. Source control ranks above containment and recovery because uncontrolled release defeats every downstream measure.