Philippe Cousteau went diving with ABC news into the oil slick spilled by BP's Deepwater Horizon rig.
"This is a nightmare...a nightmare," he said.
He's never seen anything like it. Dispersant COREXIT 9500 has been mixing with the oil and sinking down slowly to the sea floor, where experts say it has already killed a quarter of marine life. There have been reports of oil-dispersant blobs suspended at various depths throughout the affected area. Divers had to don hazmat suits to get a glimpse of the spill that we haven't seen yet. This is a must see!!!
Video here (ABC News)