I work for a state highway department. We build highways, and bridges, and sign structures, and ... .

Some years back, a semi-truck was driving east on I-40 near Checotah, Oklahoma, having picked up a load of 2000 pound bombs from the McAlester Army Ammunition Depot in Oklahoma; that depot fills bomb casings, artillery shells, and other things with explosives, stores them, and puts them on various types of transport for shipment to units that need them.

A car driving the wrong way on an exit ramp collided with the truck, was pinned between the rig and a guardrail, and caught fire. The fire spread to the rig, setting the wooden trailer bed, the tarp, and (finally) the crates on fire. The driver got on the horn, called the state highway patrol, and had them block I-40 a few miles upstream and down. They also evacuated the town of Checotah.

About 30 minutes later the first bomb cooked off, setting off another 2,000 pounder by concussion.

It took most of a week to fill the crater (27 feet deep, 35 feet wide) and put new road down in both directions. I think we had to put down something like 500 or 1000 feet of road each way.

We also use explosives in construction. Most of the rock removed from the cuts through the Arbuckles on I-35 north of Ardmore was done with ANFO pumped into holes bored in the rock. ANFO is low brisance: it's a mover, not a shatterer. TNT and its kith and kin are high brisance, and make little rocks out of big ones, rather than move lots of rock out of the way.

GB connection: back when we were doing the I-35 cuts, most of the radio gear would have been glowbug. I think our base rigs here use GB amplifiers in the ~150 MHz public safety band.