Paragraph 12 Obstruction in riverI1

If any pile, stump or other obstruction to navigation becomes exposed in the course of constructing any tidal work (other than a pile, stump or other obstruction on the site of a structure comprised in any permanent work), the undertaker, as soon as reasonably practicable after the receipt of notice in writing from the Tees Port Authority requiring such action, must remove it from the river or, if it is not reasonably practicable to remove it—