Thank You Greg. This is new construction with Pex, and no gas at all. So the Ufer is the only grounding electrode. Our local AHJ seems to think there must be at least one GEC in the system sized to table 250.66, so if there is only one grounding electrode they consider it the "main grounding electrode" and want the GEC sized to the table regardless of the grounding electrode type. They will only allow the #4 to the Ufer as a tap from another GEC sized to table 250.66.
Last edited by BigB; 02/05/12 02:38 PM.
