I remember an ex telling me a story when she lived in WV near the river. It was where Beyer and those types had their commercial plants. One of which was a fertilizer plant, which exploded. People were told to pretty much stay indoors, and she said the air still burned.
This type of fertilizer is what was used in the OK City bombings, so the scope really doesn't surprise me. I'm surprised it doesn't happen more though.