This is why should never-ever directly bury cables in the ground/walls/floor and ALWAYS use rigid PVC and/or flexible PVC tubes from site to site and pull the fiber or UTP cables through those tubes.

As an alternative if you are networking a single location and you don't mind seeing some finishing profiles on the walls (or want something easy in a pre-existing situation) you can also drill somewhere along the wall and feed the cables directly down to the floor or up the ceiling and cover them up.

But always, ALWAYS, make them easily accessible and easily removable.

Got plenty of experience to say no cable will survive a lifetime, and if you experience a problem without easy access you are fucked.