THE ATOM BOMB AT LOS ALAMOS?

No definitive answer here, only an educated guess. I was in the Air Force for 22 years and part of that time spent in a sort of logistic arm of nuclear arsenals. I studied as much as I could get away with about the weapons we possess. That is my source credentials.

Trinity, the site of the first test, is still radio active as far as I know. The first explosion was a fission bomb, it split atoms to achieve the energy to do the damage. By today's standards the first bomb was extremely dirty. I.E. a lot of radiation and said radiation had a very long half-life. To make glass one needs a serious heat source, the bomb under discussion was a very serious heat source so the silicates in the sand were fused into "glass". I would think the quality to be very questionable. Glass isn't terribly difficult to make but good quality not only requires heat but that heat must be very controllable. If glass it not cooled slowly it will fracture and my bet would be that the glass around Trinity fractured very soon after the blast while it was experiencing an uncontrolled and rapid cooling.

FYI; today's weapons are not the fission type; they are the fusion type. Sometimes referred to as Hydrogen Bombs they actually fuse materials into heavier elements much like what happens inside a star. Unless things are different from when I retired the fusion device actually uses a fission device to start the fusion reaction.

These weapons as well as power generating reactors are very complex devices. I would argue that an accidental detonation is so remote as to be statistically unmeasurable. Someone might lose a device but it won't blow up because it fell off an airplane or because a reactor went into meltdown. A reactor in meltdown can release a great deal of radioactive steam but there is simply no way it will turn into a nuclear detonation.

Cheers, hope that sheds a bit of light.

GIMP

The bunker they were in was very far away from blast. Most of that area had some radioactivity. It would have very little if any today. Don't know kind of glass that was used. It may have been reused. The danger of residual low level radioactivity was not fully known.