Which statement about underground cables when de-energized is correct regarding grounding?

• A. They are already in the ground and grounded by the concentric neutral conductor
• B. Both ends of the line must be visually verified open prior to contact
• C. Because of the capacitive nature of underground cable there is no reason to apply grounds
• D. None of the above

Answer: (D)

Grounding underground cables when you’re working on them is about creating a definite, low-impedance path to earth so any fault or residual voltage is safely dissipated and the work surface remains at earth potential. You can’t rely on shielding or on what you might see in the conduit alone.

Even if a cable has a concentric neutral or shielding, that doesn’t automatically provide a safe, working-ground path at the point you’re operating. Grounding paths must be established for the specific task and location, and must be verified with proper testing rather than assumed.

Visual verification of ends isn’t practical for underground circuits. The ends aren’t readily accessible or visible, and de-energization must be confirmed through appropriate testing and lockout/tagout procedures to ensure no voltage can appear unexpectedly.

Capacitance and stored energy in underground cables can leave voltages present even after de-energization. That’s why it’s necessary to apply a grounding path and verify the circuit is safe, rather than assuming there’s no risk.

So none of those statements alone correctly describe the safe, standard practice. The correct approach is to follow approved switching, isolation, and grounding procedures—verify absence of voltage with proper testing, ensure all sources are opened, and establish a grounded path to guarantee safe conditions for the work.