Berms built to about 15 ft high with a wide base would certainly mitigate the damage and causalities.
I ran preliminary design calcs to meet explosive codes/requirements about 10 years ago and they had to be something like 20-35 ft tall. That was only for a safehaven for a tractor trailer, granted it was on a slope which exasperated the problem.
Current ATFP stds require something like twice the Bldg height, then in profile a distance beyond which the shock wave doesn’t drop in elevation to any occupied structure.
Atd Bldg height with max 12ft story is probably about 15’ (maybe higher). Probably looking at something around the 30s to 40s to begin that approach.
FWIW, the codes generally approach the topic by first addressing the risk. Statistics and percentages.
Then they look at risk reduction factors.
1st line of defense probably should be fire protection and fire alarm.
It usually takes a fair amount of time for an ammonium nitrate storage to detonate,...I believe this fire beganin the morning, was thought to have been put out, then discovered to be smoldering again, then worked again with windy conditions.
Great Texas City Explosion was similar. Fire was believed to have been put out but the fertilizer smoldered. Ship Captain sealed the compartment believing lack of air would snuff out the fire, but in that chemical fire, the reaction continued.
IMHO, instead of chasing after codes, insisting more regulations be made and the public and businesses further yoked, first look at more reasonable methods of prevention.
What started the fire?
Why did it spread to the vicinity?
Why wasn’t it immediately extinguished?
Why weren’t there sirens and public alert systems in place?
The people in the business likely know the business much better than you, myself, and definitely a set of codes, which nobody can afford anyways. Keep it simple and locally controllable.