Samples are to be taken each year except in the case of class E supplies (see note 5). If more than one sample is required, the samples must be taken on separate occasions.

The basic parameters are listed in column (1) of Part II of this Schedule.

The additional parameters are listed in column (2) of Part II of this Schedule. The local authority must sample for any additional parameters which they consider should be taken because of the characteristics of the locality or of the supply’s distribution system.

The coliform parameters are total coliforms and faecal coliforms. Sampling for coliform parameters is additional to the coliform sampling carried out as part of sampling for basic parameters and must be carried out on separate occasions.

Class E supplies are to be sampled once for basic and additional parameters before 31st December 1994 unless–

From 1st January 1995 all class E supplies are to be sampled once every 5 years.

The sampling frequency should be halved if the premises served by the supply are used for not more than six months in the year.

In 1992, or in the first year in which the supply is used as a class 3 supply, 2 samples must be taken in the first two months of the year and 3 in the remainder of that year.

Samples need not be analysed for lead if the local authority are satisfied that lead pipework or solder is not present in the plumbing of the property or that naturally occurring lead is not present in the water.

Samples need not be analysed for nitrate if the local authority are satisfied that nitrate levels in the locality concerned are below 25 mg NO₃/l.

Samples should not be assessed qualitatively for taste if the person taking the samples has any reason to suspect that the water may give rise to a health hazard.

The sum of the detected concentrations of fluoranthene, benzo 3.4 fluoranthene, benzo 11.12 fluoranthene, benzo 3.4 pyrene, benzo 1.12 perylene and indeno (1,2,3-cd) pyrene.