You're right to question the aluminum conductor in this application. Based on the information you provided, it likely is a violation. Let's break down why

Understanding the Roles:
Concrete Encased Electrode (CEE)

This is a grounding electrode, typically a length of rebar embedded in the concrete foundation of the building. It's part of the overall grounding system and intended to provide a connection to the earth.

Grounding Electrode Conductor (GEC)

This conductor connects the CEE (or other grounding electrode(s)) to the service equipment (neutral bus, service disconnect).

Service Disconnect

This is the main disconnect for the entire electrical service.

NEC 250.64(A)(1)

This section deals with the installation of grounding electrode conductors (GEC). While it doesn't explicitly prohibit aluminum for all GECs, it states:>

Aluminum or copper-clad aluminum grounding electrode conductors shall not be used where in direct contact with masonry or the earth or where subject to corrosive conditions.Why the Aluminum Conductor is Problematic (Likely a Violation)


Coming out of Concrete

The fact that the aluminum conductor is emerging from the concrete is the key issue. Concrete is alkaline and will corrode aluminum over time. This is exactly the scenario 250.64(A)(1) is trying to prevent. The aluminum is in direct contact with the masonry.
2.

GEC Function

The conductor you saw is acting as the GEC or is connected to the GEC to the CEE, making 250.64(A)(1) apply to the conductor.
3.

"Inside the Building" Argument Doesn't Hold

The argument that it's "inside the building" is irrelevant. The critical factor is that it's in contact with the concrete. Whether the concrete is inside or outside the building's walls is immaterial. The corrosion will still occur.

In summary, the aluminum conductor coming out of the concrete and connected to the service equipment is most likely a violation of NEC 250.64(A)(1) because it's in direct contact with masonry.How to Address It


Document the Issue

Take clear pictures of the installation.2.

Inform the Client (Respectfully)

Explain why you believe it's a violation and cite NEC 250.64(A)(1).
3.

Suggest a Solution

The common and compliant solution is to:

Replace the aluminum conductor with a copper conductor of appropriate size. If it's not possible to easily replace the entire conductor, install a copper conductor of proper size and approved connector to the aluminum before it enters the concrete. The copper conductor is then run to the service disconnect. This keeps the aluminum from being in direct contact with the masonry. Another option, while not always practical, is to completely isolate the aluminum from the concrete with a non-corrosive raceway or coating. However, this is often difficult to achieve effectively and maintain over time.4. Follow Local Codes and AHJ

Remember that local codes or the Authority Having Jurisdiction (AHJ) may have additional requirements or interpretations.

Important Considerations



Older Installations

It's possible this was installed before the current code cycle. However, even if grandfathered, it's a safety issue and should be addressed, especially if there's evidence of corrosion.*

Enforcement: Ultimately, it's up to the electrical inspector to determine if it's a violation.You were right to question this installation. A properly installed and maintained grounding system is essential for electrical safety. Flag for review