I've been away for a couple of days - our department was at the derailment. Though the information is no longer timely, I feel a point or two needs clarification.
The flight restriction was placed because of safety concerns for the media's helicopters. We had enough to deal with on the train wreck. We didn't need a helicopter crashing because the bad stuff got into the engine and conked it out. Auto rotating is fine as long as you don't auto rotate into the fire.
Us responders like to see what the helicopters can see - we even sent a guy up in a police helicopter to do recon. So having the media's helicopters close enough to film serves our desires too, particularly to have the record for prosperity and old time's sake. (BTW Motor vehicles were kept farther away than helicopters.) We do get along amicably with the media for the most part.
As far as the "If it hadn't blown by now, it won't." is horribly incorrect. There's some folks in Waverly Tennessee who took the long dirt nap because of an explosion that occurred days after a train wreck that happened long ago.
At the Bullitt county incident, more than 12 hours after the wreck, a relief valve cut loose releasing product. Sometimes a nearly empty train car is more dangerous than a full car. On the ground, we can hear relief valves opening up and can dive into a ditch for cover to escape from something blowing off a train car. You can't hear that in a helicopter, and even if you could, there ain't no ditches up there to dive into, or firetrucks to cower behind.
The feds there were there (EPA, NTSB and federal railroad administration) didn't have any radios I could see. They used cell phones.
