An anonymous visitor to my table at the Detroit Maker Faire mentioned that he worked for an undisclosed company that was using proprietary methods for locating valves in underground oil pipelines. These valves were then removed before they sprung a leak.

He said the company considered using ground penetrating radar, but decided against it because of the cost ("$50,000 to $100,000 per system").

I wonder how many potential problems could be located and mitigated with an unmanned ground penetrating radar system that costs 20% of current manned systems?

I'll probably need to increase the frequency to be able to see the target signature of valves in a 3" pipe at "backhoe depth." But, it's on my growing list of targets.

First, I'm going after the elephant in the room.