In section 4(5) of that Act (under which disputes arising under that Act as to the discharges of trade effluent which were made during such a period as is mentioned in subsections (1) or (2) of that section are to be determined by the Secretary of State) for the words “this Act” there shall be substituted the words “section 43 of the Control of Pollution Act 1974” and for the words “is mentioned” there shall be substituted the words “before the repeal of those subsections by that Act was mentioned”.