Which of the following meets the criteria for a Ufer ground?

The Ufer ground, also known as a concrete-encased electrode, is an effective grounding method established under the National Electrical Code (NEC). It typically involves a grounding conductor that is encased in a concrete footing or foundation, which enhances its effectiveness due to the conductive properties of the concrete, especially when it is in contact with the soil.

For an installation to qualify as a Ufer ground, it generally must have a minimum length of conductive material that is embedded in the concrete, which is often specified at least 20 feet. Both options discussing rebar and copper meet this criterion in their respective contexts.

The first scenario, involving 40 feet of 1/2" rebar in a footing, satisfies the minimum length requirement and is made of an acceptable conductive material. Similarly, the second scenario, with 25 feet of 1 AWG bare copper in a grade beam, also fulfills the necessary criteria due to its length and conductive properties.

Thus, the choice indicating that both the 40 feet of rebar and the 25 feet of bare copper meet the requirements for a Ufer ground is accurate, as both setups provide an effective grounding method through their respective conductive materials embedded in concrete. This allows the grounding system to function