I'm not an expert and it's been a long time, but I recall reading articles at the time that they were dumping chemicals in the ocean that basically bound to the oil to split it apart and make it sink. Out of sight out of mind.
The implication was they could have contained it at the surface, sucked it up and treated it to remove oil from the water.
The implication was they could have contained it at the surface, sucked it up and treated it to remove oil from the water.