Any person designated in writing for the purpose by a relevant undertaker may enter any premises for any of the purposes specified in subsection (2) below.
The purposes mentioned in subsection (1) above are—
the carrying out of any survey or tests for the purpose of determining—
whether it is appropriate and practicable for the undertaker to exercise any relevant works power; or
how any such power should be exercised;
or
the exercise of any such power.
The power, by virtue of subsection (1) above, of a person designated by a relevant undertaker to enter any premises for the purposes of carrying out any survey or tests shall include power—
to carry out experimental borings or other works for the purpose of ascertaining the nature of the sub-soil; and
to take away and analyse such samples of water or effluent or of any land or articles as the undertaker—
considers necessary for the purpose of determining either of the matters mentioned in subsection (2)(a) above; and
has authorised that person to take away and analyse.
Part II of Schedule 6 to this Act shall apply to the rights and powers conferred by this section.
In this section "relevant works power" means any power conferred by any of the provisions of sections 158, 159, 161, 163 and 165 above, other than section 161(3).