(2) Where a monitoring local authority considers that one or more of the parameters listed in the Table in this Schedule is not likely to be present in a Type A supply in its area in concentrations which could lead to the risk of a breach of the parametric value in respect of the parameters specified in Table B of Schedule 2, it shall undertake such investigations as are considers reasonable to satisfy itself–
(a)that the circumstances referred to in column 3 of the Table in this Schedule in respect of that parameter do not exist; and
(b)whether any of the conditions referred to in column 4 of the Table in this Schedule in respect of that parameter, apply.