Table 110.34(A) voltage to ground?

[Dale001289]

Before I break the bad news to our subcontractor, is this correct?
On a 13.8kV 3ph 3W ungrounded system - since ‘voltage to ground’ does not exist, you have to use the full 13.8kV as the “Nominal Voltage to Ground” when applying minimum clear distance per Table 110.34(A).

 

[infinity]

From Article 100:

Voltage to Ground. For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit. (CMP-1)