Mushroom Cloud blast (Score 2, Informative)

My former boss worked for a decade at a New Mexico university (not sure which one) doing highspeed photography work. He had compiled a tape of much of the non-classified footage he had accumulated over the years. He lent it to me and I found it some very cool footage. It contained several conventional weapons detonations including one 20,000 ton TNT blast. It created a mushroom cloud exactly like what I have seen off nuclear weapon blasts. Mushroom cloud != Conspiracy Residual radition = Conspiracy (for me) But I've seen no evidence for any. Case closed.