Since you are in S. Cal you can bet your pipe is the cheapest Cr%^ that he could buy and the Asians cast from our old rebar. Or melted down 1940's USA pipe that lasted until 1990.
I would never put that sabotage pipe in my drinking water. PVC only or even 200 PSI Poly.
If he had used rubber splicing tape and then Scotch 33, at least that portion would remain. But all the other joints will rot inside and out.
The old school guys love iron, because only they can pull it with LOOOONG labor and big machines, and it insures the call backs.
The only pipe, if you love iron, would be a US made pipe with SPECS as to metallurgy and zinc thickness. Otherwise, join the new century and set plastic pipe that you can be sure your grandkids can put back in the well. Steel is for fences, axles, and oil wells.
Electrolysis is a major science in metal piping, but here you just have "harbor fright" pipe, with varying wall thickness and uneven galvanizing [the spots you saw] Its called the begining of the end of America from Chinese industrial sabotage.
Headlines in the Wall Street Journal today about the Chinese stealing superconducting software used in US wind turbines that looks like it will close a few major American factories and eventually give them the entire industry.
Between Canada and the US and Mexico, not a single rolling pin or clothespin factory remains. They are working now on our last wooden match factory, and when a country can't make matches, the end is near.
Vietnam single handedly closed 28+ furniture factories in the East US and put hundreds of thousands out of work.
But hey -it's Free trade and NAFTA and "favored nation" status, so WE can become a third world nation.
