Floodwaters from the east would carry toxic waste from the "Industrial Canal" area, nicknamed after the chemical plants there. From the west, floodwaters would flow through the Norco Destrehan Industrial Complex, which includes refineries and chemical plants, said Ivor van Heerden, director of the Louisiana State University Public Health Research Center in Baton Rouge. Van Heerden has studied computer models about the impact of a strong hurricane for four years. "These chemical plants [could] start flying apart, just as the other buildings do," said van Heerden said. "So, we have the potential for release of benzene, hydrochloric acid, chlorine and so on."
That could result in severe air and water pollution, he said.

In New Orleans, which lies below sea level, gas and diesel tanks are all located above ground for the same reason that bodies are buried above ground. In the event of a flood, "those tanks will start to float, shear their couplings, and we'll have the release of these rather volatile compounds," van Heerden added.

Because gasoline floats on water, "we could end up with some pretty severe and large -- area-wise -- fires."

"So, we're looking at a bowl full of highly contaminated water with contaminated air flowing around and, literally, very few places for anybody to go where they'll be safe."

He went further.

"So, imagine you're the poor person who decides not to evacuate: Your house will disintegrate around you. The best you'll be able to do is hang on to a light pole, and while you're hanging on, the fire ants from all the mounds -- of which there is two per yard on average -- will clamber up that same pole. And, eventually, the fire ants will win."