I am referring to the exhibit which shows different electrodes bonded together above ground, I am just confirming that it's not mandatory to bond above ground.
Can depend on bonding method, but as general rule not necessary to be above ground. Connection doesn't need to be accessible for buried electrodes, say a jumper from one ground rod to another or from a CEE to another electrode, must of course use a connection method rated for the conditions.
Bonds to building steel or to a water pipe electrode must remain accessible though. A CEE that is extended out of the concrete to make connection must also have accessibility to that connection, but if the connection is encased in the concrete that is fine as long as it is a connection rated to be encased in concrete.
