30.—(1) This regulation applies to any Type B supply sampled by a monitoring local authority in accordance with regulation 29.
(2) A monitoring local authority may sample every appropriate Type B supply in its area in respect of any property, element, micro-organism, parasite or substance which fulfils the conditions specified in paragraph (3).
(3) The conditions specified in this paragraph are that—
(a)the supply may have or contain a property, element, micro-organism, parasite or substance not listed in Table C of Schedule 2; and
(b)the monitoring local authority reasonably believes that the concentration, amount or number of the property, element, micro-organism, parasite or substance may be such that it may (whether alone or in combination with a parameter or any other property, element, micro-organism, parasite or substance) cause the supply to fail to satisfy the provisions of regulation 7(3).
(4) A monitoring local authority may cause to be taken such samples at such frequency as it considers appropriate having regard to any anticipated risk of danger to human health, and which are representative of the quality of water intended for human consumption purposes throughout the year.