One thing I remember hearing is this was a volunteer fire dept. Who knows how much training they had on fighting such a fire?
First rule in training for the local volunteer fire dept. here is to set back and watch the fire burn ,on the up-wind side
Every fire fighting apparatus in the US is required to carry a hazmat guide. It lists what to and what not to put on different fires and safe evacuation and hot zone distances.
There clearly was some miscommunication, at best.
Listening to the scanner feed real time, the incident commander announced at about 10 pm that they had a rail car delivered that morning containing 200k plus lbs of ammonium nitrate.