(with tongue in cheek) I've always found that backhoes are excellent at locating underground pipes, seems where ever they digm they always manage to hit something.

Have any friends at the gas company?They usually have a tracer that puts a signal on a wire so they can find their buried plastic lines. You could run your fishtape into the conduit, put the signal on the tape & trace it.

If you've got the bucks, General Electric has a rental program & they rent all kinds of electrical test gear.

Tom

Few things are harder to put up with than the annoyance of a good example.