Q. What is the minimum burial depth requirement for residential service lateral conductors installed in rigid nonmetallic conduit?

A. Cables and raceways run underground must have a minimum “cover” in accordance with Table 300.5. This table requires a minimum of 18 inches of cover. According to Note 1 to Table 300.5, “Cover” is defined as the distance from the top of the underground cable or raceway to the surface of finish grade.