The projects I work on usually have hundreds of feet of piping for the sprinklers until they get to the source (running to the PIVs then to the DC). The cold water seems to always be ran in PVC until close to the building. Even if the cold water was ran in copper it would probably be a 500-1000' loop between the two (I am not even sure if they are served by the same source). But would that distance be considered properly bonded?