From my readings, a UFER is hands down the best earth contact .
Unfortunately, most sparks up my way are contracted after the 'crete is poured.
The state did make a good faith effort to contact most of the 'crete guys , which ended in 'best guess' stub up's where metering and switchgear might end up.
Yet no spark walking into these can prove their viability, so most of us do the whole grounding routine ,and just include the stub in
~S~
