I would have suggested an electrical, rather than a plumbing, solution to the pinhole leaks. A grounding problem will cause the leaks. You should have called an electrician (one with a concave back and a convex forehead) to do a very meticulous current analysis, tracing all the existing and former wells, pipes, electrical bonds, ground rods, and low-voltage utility connections, to determine if your problem was caused by current leakage.
I have experience in this line of work, and can assure you that grounding and bonding issues can cause lots of plumbing headaches.