44.—(1) The Welsh Ministers must establish a monitoring programme to assess the effectiveness of the measures imposed by these Regulations as a means of reducing or preventing water pollution from agricultural sources.
(2) At least every four years, the Welsh Ministers must review the effectiveness of the measures imposed by these Regulations as a means of reducing or preventing water pollution from agricultural sources and if necessary revise them.
(3) When carrying out a review under paragraph (2), the Welsh Ministers must take into account—
(a)available scientific and technical data, particularly with reference to respective nitrogen contributions originating from agricultural and other sources, and
(b)regional environmental conditions.
45.—(1) If proposals for an alternative suite of measures for delivering the outcomes in regulation 44(1) are received within 18 months of these Regulations coming into force, the Welsh Ministers must consider whether those measures would deliver the outcomes more effectively than the measures contained in these Regulations.
(2) If the Welsh Ministers are satisfied that proposals submitted under paragraph (1) would be more effective in delivering the outcomes in regulation 44(1), they must publish a statement within two years of these Regulations coming into force, explaining what action will be taken.