I have old clay tile in draws that have new plastic tile installed separated from the clay and deeper.  The clay tiles are clear and rarely run water.   The clay is occasionally broken or chipped and a tile hole develops.   I would like the clay to fill in with dirt.  I am looking for a way to keep the clay from making tile holes.   I wonder about digging to the clay tile at a tile hole,  and dumping in a 1/2 a loader bucket of rock.   Then filling the  rock over with dirt.   Would this help to get the clay tile to fill in?   I am chasing holes in old clay and would like to find a solution.