Amend NEC^® 2017, page 112:

250.50 Grounding Electrode System. All grounding electrodes as described in 250.52(A)(1) through (A)(7) that are available at each building or structure served shall be bonded together to form the grounding electrode system. Where none of these grounding electrodes exist, one or more of the grounding electrodes specified in 250.52(A)(4) through (A)(8) shall be installed and used.

Exception: Concrete-encased electrodes of existing buildings or structures shall not be required to be part of the grounding electrode system where the steel reinforcing bars or rods are not accessible for use without disturbing the concrete.

ELR commentary: The 2017 NEC^® states that all grounding electrodes as described in 250.52(A)(1) through (A)(7) that are present at each building or structure served shall be bonded together to form the grounding electrode system.

North Carolina has changed the word “present” to “available”. Sometimes a new building foundation may have ½ inch or larger rebar near the bottom of the footing that may constitute a concrete encased electrode. Often, the foundation crew gets to the job site and pours the footings and the concrete slab long before the electrician is scheduled to come out. It is difficult to ask the electrician to chip away the footing to expose and connect to the concrete encased electrode since it is “present”.

North Carolinas amendment to this section is intended to avoid this costly requirement.