Drilling for supports, I guess

Probably putting in piles to get support below the water table. It looks very technical whatever they're doing. Fascinating photo Diane.

Probably required by building codes. I doubt it's for soil samples, but maybe looking for diamonds!

Yes, something like that. A concrete parking garage is pretty heavy, so I imagine they need "anchors!" It doesn't look too unusual, to me, but I'm just a casual observer. Oh, also, every few decades there is an earthquake in the moderate category, here. Enough to have destroyed several 3-story brick buildings on Main St. in 1996. That included the courthouse and part of the cocunty gov't building.

Oh, do you have a water table there? It looks like desert to me. I like the earthquake theory.