4(1)The Development Corporation shall—U.K.
(a)before the commencement of impoundment, and
(b)during the period beginning two years, and ending three years, after the commencement of impoundment,
arrange for a survey of every building within the protected property area.
(2)The owner or occupier of, or of any part of, a building within the protected property area may during the period beginning three years, and ending twenty years, after the commencement of impoundment require the Development Corporation to arrange a survey of the building; but no more than one survey of a building may be required under this sub-paragraph.
(3)The owner or occupier of, or of any part of, a building within the protected property area may at any time during the period beginning with, and ending twenty years after, the commencement of impoundment when he is able to show a justifiable concern that the building has suffered or is likely to suffer groundwater damage require the Development Corporation to arrange a survey of the building.