Grounding electrode conductor connections are required to be accessible in all but which of the following locations?

Grounding electrode conductor connections being required to be accessible is a critical aspect of ensuring that electrical systems can be safely maintained and inspected. In the case of buried electrode connections, these do not typically need to be accessible. This is because soil and moisture can contribute to corrosion and degradation, making it impractical to maintain or inspect these connections regularly.

In contrast, connections made in accessible attics or above-ground locations, concrete-encased electrodes, and connections under fire-proofing materials are intended to be accessible for inspection and maintenance purposes. The accessibility allows for timely checks to ensure that the grounding system is functioning correctly, which is essential for electrical safety.

Therefore, buried electrode connections stand out as the exception in this context since they remain protected by the ground, thus removing the need for regular accessibility while still fulfilling their grounding function.