The Water Intended for Human Consumption (Private Supplies) (Scotland) Regulations 2017

3.  Subject to paragraph 4, based on the results of a risk assessment the list of parameters in Part B of this schedule (including any micro-organism, parasite or substance referred to in paragraph 2(1)(b) of that Part) and the sampling frequencies under that Part B may be reduced, provided that the following conditions are met:—

(a) the frequency of sampling for Escherichia coli must not be reduced below the minimum frequency required by that Part B; and

(b) for other parameters in the list—

(i) the location and frequency of sampling must be determined in relation to the parameter’s origin, as well as the variability and long-term trend of its concentration, taking into account the water quality standards;

(ii) to reduce the minimum sampling frequency for a parameter under Part B of this schedule, the results obtained from samples collected at regular intervals over a period of at least 3 years from sampling points representative of the whole supply zone must all be less than 60 % of the parametric value;

(iii) to remove a parameter from the list of parameters to be monitored under Part B of this schedule, the results obtained from samples collected at regular intervals over a period of at least 3 years from points representative of the whole supply zone must all be less than 30 % of the parametric value; and

(iv) the removal of a parameter from the list of parameters to be monitored under Part B of this schedule must be based on the result of the risk assessment, informed by the results of monitoring of sources of water and confirming that human health is protected from the adverse effects of any contamination of water.