6.—(1) An authorisation shall not be granted in relation to–
(a)any direct discharge of any substance in list II;
(b)any disposal or tipping for the purpose of disposal of any substance in list II which might lead to an indirect discharge of that substance;
(c)any other activity on or in the ground which might lead to an indirect discharge of any substance in list II,
unless that activity has been subjected to prior investigation.
(2) An authorisation may only be granted if, in the light of any such investigation, it includes conditions which require that all necessary technical precautions are observed to prevent groundwater pollution by any substance in list II.
(3) The Department shall not grant its consent under Article 46(4) of the Roads (Northern Ireland) Order 1993 for the discharge of any substance in list II into a road drain if the discharge results in that substance polluting groundwater.
(4) The powers conferred by regulation 18 shall be exercised if it is necessary to do so for the purposes of avoiding pollution of groundwater by substances in list II due to activities mentioned in paragraph (1)(c).