(1) The Central Government may, subject to the provisions of this section, do on, over or below the surface of any land such work as it considers necessary for the purpose of discovering whether there is present in or on the land, either in a natural state or in a deposit of waste material obtained from any underground or surface working, any substance from which in its opinion any of the prescribed substances can be obtained, and the extent to which such substance is so present.
     (2) Before any powers are exercised under sub-section (1) in relation to any land, the Central Government shall serve on every owner, lessee and occupier of the land a notice in writing specifying the nature of the work proposed to be done and the extent of the land affected, and the time, not being less than twenty-eight days, within which and the manner in which objections can be made thereto, and no such powers shall be exercised otherwise than in pursuance of the notice or before the expiration of the time specified therein for making objections.
     (3) The Central Government may, after giving the person making the objection an opportunity of appearing before and being heard by a person appointed by the Central Government for the purpose, and after considering any such objection and the report of the person so appointed, make such orders as it may deem proper but not so as to increase the extent of the land affected.
     (4) Compensation shall be determined and paid in accordance with section 21 in respect of any diminution in the value of any land or property situate thereon resulting from the exercise of powers under this section.