Iron pins and permanent markers shall be set under the direction of a registered surveyor at all changes in direction of all outside boundary lines of the platted property and at all changes in direction of the right-of-way lines. Iron pins shall be ¾-inch inside diameter, 30 inches long with a plastic plug placed in the top bearing the initials of the surveyor. Permanent markers shall be 1 inch inside diameter, material 30 inches long, buried six inches in depth below final grade with a plastic plug placed in the top bearing the initials of the surveyor. A minimum of four permanent markers shall be set. All monumentation shall meet the minimum standards for boundary surveys in the State of Ohio.