On the issue of a notification under sub-section (1) of section 20A, it shall be lawful for any person, authorised by the competent authority in this behalf, to—
(a) make any inspection, survey, measurement, valuation or enquiry;
(b) take levels;
(c) dig or bore into sub-soil;
(d) set out boundaries and intended lines of work;
(e) mark such levels, boundaries and lines placing marks and cutting trenches; or
(f) do such other acts or things as may be considered necessary by the competent authority.