Underground electrical duct banks

[Glenn Becnel]

An electrical contractor is installing an underground conduit for a service feeder (3 phase, 480V). The conduit will have approx. 18" of cover over a concrete envelope. The contractor wants to install a potable water line in the same trench. The contractor says the conduit & piping will be in the same concrete enevelope. Is this permissible, per the NEC? Please state the article.
Thanks in advance for your help.

 

[don_resqcapt19]

Re: Underground electrical duct banks

The code does not prohibit this installation, but putting the water line in the concrete encasement will make any required repairs almost impossible.
Don