Brian,
There shouldn't be a Grounding Electrode Conductor (GEC) connected at these panels, if they are sub-panels. The GEC connection to the grounded (neutral) conductor would be made at the main service equipment.
Maybe you meant Equipment Grounding Conductor (EGC). If the panels are supplied with metal conduit, you would not neccessarily see an additional conductor for equipment grounding. The metal conduit is often permitted to perform that function.
Ed
