That's a great question, and one I'm starting to wonder myself. I'm not ready to have it dug out quite yet, so I guess I need to "take the plunge" and see how far down the rust has spread in that 40 feet of pitch blackness...
Maybe I can talk my husband into going in first and I'll video-tape it!
Seriously, I do need to figure out how much of that culvert will need treating.
