how deep direct burial electrical wire
Direct Burial of Cables or Conductors. Underground feeder cables, labeled UF, can be buried without additional protection from conduits because they have a tough jacket designed for burial. Bury UF cables 24 inches below the soil surface, and 18 inches deep when protected by 2 inches of concrete. For all other applications, the burial depth is the same as specified for conduits, except that conduits are required for UF cables in 2 inches of solid rock.