As I’ve mentioned before on this site, one of my jobs titles is GPR Technician. GPR stands for Ground Penetrating Radar, and is the sort of thing you see on CSI when they are looking for buried bodies and such. Although I have located graves before, it is not the typical kind of job I get. Usually I’m looking for buried utilities or utilities embedded inside of concrete floors, walls, etc.

I had a couple of odd ball jobs Tuesday and Wednesday (both in Philadelphia) and I thought I’d share a little slice of my life with you all.

Tuesday I worked here:


A conference room in the Four Seasons Hotel.

I had to map out the “waffle” pattern of the suspended slab. The topside of the floor is flat of course, but the bottom really does look like a waffle. Here is what it looks like on my radar screen:



The customer wants to drill some holes in order to install outlets in the floor, but they don’t want to drill into the thick part of the waffle. So I scanned it, marked the thick parts with blue painters tape to establish the pattern, then took measurements so I can transfer my finding to the drawing.



It was a nice, clean job – unlike Wednesdays…


I took a picture with the flash and only got smoke and dust.

…which was below ground, hot, dusty, smoky, smelly, and all-around not too much fun. I was a little worried about the air quality because concrete dust causes silicosis, an irreversible lung disease. Fun.

Here, I was mapping out the voids under the concrete floor. Under to floor should have been dirt, but most of it turned out to be air. The purple hatched areas are the bad spots.





The reason for all the dust, smell, and heat was that they were removing a vault in the room next door, using welding torches and jackhammers.


The Vault.


Pan of Downstairs.

Entryway, looking upstairs and down.


Safe Deposit Department.