Class 85—(1) The use of land by or on behalf of the Crown for the stationing and operation of apparatus in connection with the carrying out of surveys or investigations.
(2) Development is permitted by this class subject to the condition that on or before the expiry of the period of six months beginning with the date on which the use began, the use shall cease, any apparatus shall be removed, and the land shall be restored to its condition before the development took place, or to such other state as may be agreed in writing between the local planning authority and the developer.