Fiber Optics and MV cables

[Cloud]

We are currently installing 36kV cable parallel with a fiber optic (data)- directly buried. Are we allowed to combine these cables, IFC drawings shows 150mm distances in between but the contractor is arguing that there will be no interference even if we bundled it together.

I said stick to the drawing regardless. But do we have any code for this? Is 800.52 applicable?
Thanks!

 

[big john]

770.133 covers separation from fiber and power conductors, and mixing them is permitted in industrial application. But yours almost sounds like a utility installation, which would be outside of the scope of the NEC regardless.

On the note of interference, I can say that I've installed MV cables that had fiber built directly into them to enable remote communication. In addition, fiber is often installed on transmission lines to assist in relaying. So, I don't think putting them in the same trench is of any concern.