21(1)A person duly authorised in writing by the Development Corporation may at any reasonable time—U.K.
(a)enter any building for the purpose of carrying out a survey or monitoring of that or any other building under this Schedule,
(b)install in any building apparatus for use in connection with such a survey or monitoring, or
(c)remove such apparatus from any building.
(2)A person acting under this paragraph shall, if so required, produce evidence of his authority to do so.
(3)Such a person may take with him into the building such other persons and such apparatus as he considers necessary for the survey or monitoring.
(4)Such a person shall, if the building is unoccupied or the occupiers are temporarily absent, leave it as effectively secured against trespassers as he found it.
(5)Such a person shall not—
(a)enter the building if it is occupied unless notice in writing has been given to the occupiers of the building, or any part of it, by the Development Corporation at least twenty-eight days beforehand, or
(b)install any apparatus in the building or remove any apparatus from it—
(i)unless notice in writing has been given to the owners and occupiers of the building, or any part of it, by the Development Corporation at least twenty-eight days beforehand, and
(ii)where the building, or any part of the building, is owned or occupied by statutory undertakers or a relevant telecommunications licenceholder and a notice of objection has been served on the Development Corporation, unless the Secretary of State authorises him in writing to do so.
(6)In sub-paragraph (5) above “notice of objection” means a notice in writing stating the objection of the statutory undertakers or licenceholder to the taking of the action of which notice has been given on the ground that it would be seriously detrimental to the carrying on of the statutory undertaking or the running of the telecommunication system.
(7)A person exercising in relation to a building which, or part of which, is owned or occupied by statutory undertakers or a relevant telecommunications licenceholder any of the powers conferred by sub-paragraph (1) above, and any person whom he has taken with him under sub-paragraph (3) above, shall comply with all reasonable conditions imposed by the statutory undertakers or licenceholder.
(8)Where on an application made by the Development Corporation to a magistrates’ court the court is satisfied that—
(a)a building has suffered or is likely to suffer groundwater damage, and
(b)failure to carry out remedial work to it will probably have an adverse effect on an adjoining building,
the court may make an order empowering the Development Corporation to enter the building in order to carry out the work within such period as may be fixed by the order (beginning not sooner than twenty-eight days after the making of the order).
(9)If any person, after receiving notice of an order under sub-paragraph (8) above, prevents a person from duly implementing the order, a magistrates’ court may order him to permit to be done everything which is required in order to carry into effect the provisions of the order.
(10)In this paragraph “a relevant telecommunications licenceholder” means a person to whom there has been granted under section 7 of the Telecommunications Act 1984 a licence to which section 8 of that Act applies.