Buried pipes are, by their nature, generally inaccessible. Their earthen cover provides shielding from most accidental damage and weather and temperature extremes. But, sooner or later, buried pipes will require maintenance or replacement, and then their shield becomes their Achilles’ heel.
The previous, traditional approach to both spot repairs and restoration of lengthy deteriorated segments was to dig up the pipe and fix the problem. Excavation was messy, disruptive to nearby and competing activities, and could take a lot of time. Each of these added to project costs, which in turn reduced the total length of pipe that could be restored
