18Section 17: supplementary
(1)The power to survey land conferred by section 17(1) includes power to search and bore for the purpose of ascertaining—
(a)the nature of the subsoil, or
(b)the presence of minerals in it.
(2)But this is subject to subsections (3) to (5).
(3)No person may carry out any works authorised by virtue of subsection (1) unless notice of the person’s intention to do so was included in the notice required by section 17(2)(b).
(4)The authority of the appropriate Minister is required for the carrying out of any works authorised by virtue of subsection (1) if—
(a)the land concerned is held by statutory undertakers, and
(b)they object to the proposed works on the ground that the execution of the works would be seriously detrimental to carrying on their undertaking.
(5)The references in subsection (4) to the appropriate Minister, statutory undertakers and their undertaking have the same meanings as they have in section 325(9) of the Town and Country Planning Act 1990 (c. 8) (supplementary provisions as to rights of entry).