At what current velocities does entrainment occur, allowing oil droplets to escape under the boom?

Entrainment refers to the process where oil droplets become trapped in the water column and can escape under containment booms typically used in oil spill response. The velocities at which this occurs are critical for understanding the effectiveness of such booms in preventing oil from spreading further in aquatic environments.

The correct choice reflects the typical current velocities of 0.7 - 1.0 knots, where entrainment is observed. At these velocities, the forces at play, such as water movement and turbulence, are sufficient to disrupt the containment effectiveness of the boom. As the current speeds increase to this range, oil droplets may be forced beneath the boom due to the kinetic energy of the flowing water, making oil spill recovery more challenging.

Knowing that entrainment becomes a significant concern at these current velocities helps responders plan for spill containment strategies and design booms better suited to withstand higher current conditions. It's essential for responders to understand these dynamics to optimize their containment efforts effectively.