Regulation 2(3)
1. Subject to the following provisions of this Schedule, the criteria for the classification BW1 are that –
(a)at least 95 per cent of samples of the waters taken and tested in accordance with Schedule 2 must conform to the parametric values specified in Schedule 3;
(b)no sample of the waters taken in accordance with Schedule 2 which when tested for compliance with the phenols parameter by the absorption method or with the transparency parameter fails to comply shall have a value which deviates from the relevant parametric value for that parameter specified in Schedule 3 by more than 50 per cent;
(c)consecutive samples of the waters taken in accordance with Schedule 2 at statistically suitable intervals shall not when tested deviate from the relevant parametric values specified in Schedule 3.
2. For the purposes of paragraph 1 above samples shall be disregarded if they deviate from the parametric values specified in Schedule 3 as a result of abnormal weather conditions, floods or other natural disasters.
3. –
(1) Subject to sub-paragraph (2), where in the case of particular waters to which the classification BW1 applies –
(a)any requirement relating to the parameter for pH, colour or transparency cannot be complied with as a result of exceptional weather or geographical conditions; or
(b)any requirement relating to any parameter cannot be complied with as a result of the waters having undergone a process of natural enrichment from the soil without human intervention,
the Secretary of State may by notice served on the National Rivers Authority modify or disapply that requirement in relation to those waters.
(2) The Secretary of State shall not exercise his powers under this paragraph so as to permit a risk to public health.