See it on a lotta renos Rivet, mostly the main and branch lines, leaving the older copper intact @ the fixtures.
So many times there's a situation where, there isn't an H20 GEC, nor are the plumbing fixtures such as sink, shower,etc grounded to an ECG anymore.
I've ran #8 solid around and tagged the fixtures before, but the GEC is busted down to Rods , or in a few cases if they pour any 'Crete we'll dump 20' of CU in it
~CS~