The Private Water Supplies (Wales) Regulations 2017

PART 2E+WAnalytical methods

Commencement Information

I1Sch. 4 Pt. 2 in force at 20.11.2017, see reg. 1

Table 1

Prescribed methods of analysis for microbiological parameters

ParameterMethod
Escherichia coli (E. coli)EN ISO 9308-1 or EN ISO 9308-2
EnterococciEN ISO 7899-2
Pseudomonas aeruginosaEN-ISO 16266
Colony count 22°C — enumeration of culturable microorganismsEN ISO 6222
Colony count 36°C — enumeration of culturable microorganismsEN ISO 6222
Clostridium perfringens (including spores)EN ISO 14189

Table 2

Prescribed performance characteristics for methods of analysis for chemical and indicator parameters: trueness, precision and limit of detection (on or before 31 December 2019)

Parameter

Trueness % of prescribed

concentration or value or specification

(except for pH)

Precision % of prescribed

concentration or value or specification

(except for pH)

Limit of detection %

of prescribed

concentration or

value or specification

(except for pH)

(1)

The method of analysis should determine total cyanide in all forms.

(2)

EN ISO 8476.

(3)

The performance characteristics apply to each individual pesticide and will depend on the pesticide concerned. Values for the uncertainty of measurement as low as 30% can be achieved for several pesticides, higher values up to 80% may be allowed for a number of pesticides.

(4)

The performance characteristics apply to the individual substances specified at 25% of the parametric value in Table B of Part 1 of Schedule 1.

(5)

The performance characteristics apply to the individual substances specified at 50% of the parametric value in Table B of Part 1of Schedule 1.

(6)

The performance characteristics apply to the prescribed value of 4 NTU.

(7)

The performance characteristics apply to the specification of 1 NTU for surface waters or ground waters influenced by surface water.

Aluminium101010
Ammonium101010
Antimony252525
Arsenic101010
Benzene252525
Benzo(a)pyrene252525
Boron101010
Bromate252525
Cadmium101010
Chloride101010
Chromium101010
Colour101010
Conductivity101010
Copper101010
Cyanide(1)101010
1.2-dichloroethane252510
Fluoride101010
Hydrogen ion concentration pH (expressed in pH units)0.20.2
Iron101010
Lead101010
Manganese101010
Mercury201020
Nickel101010
Nitrate101010
Nitrite101010
Oxidisability(2)
Pesticides and related products(3)252525
Polycyclic aromatic hydrocarbons(4)252525
Selenium101010
Sodium101010
Sulphate101010
Tetrachloroethene(5)252510
Tetrachloromethane202020
Trichloroethene(5)252510

Trihalomethanes:

Total(4)

252510
Turbidity(6)101010
Turbidity(7)252525

Table 3

Method of analysis for chemical and indicator parameters: uncertainty of measurement(1)

Parameter

Uncertainty of measurement

% of parametric value

(except for pH)

(1)

The uncertainty of measurement must not be used as an additional tolerance to the parametric values set out in Schedule 1.

(2)

If the value of uncertainty of measurement cannot be met, the best available technique should be selected (up to 60%).

(3)

The method of analysis should determine total cyanide in all forms.

(4)

EN ISO 8476.

(5)

The performance characteristics apply to each individual pesticide and will depend on the pesticide concerned. Values for the uncertainty of measurement as low as 30% can be achieved for several pesticides, higher values up to 80% may be allowed for a number of pesticides.

(6)

The performance characteristics apply to the individual substances specified at 25% of the parametric value in Table B of Part 1 of Schedule 1.

(7)

The performance characteristics apply to the individual substances specified at 50% of the parametric value in Table B of Part 1 of Schedule 1.

(8)

The uncertainty of measurement must be estimated at the level of 3mg/l of TOC. CEN 1484 Guidelines for the determination of TOC and dissolved organic carbon must be used.

(9)

The uncertainty of measurement must be estimated at the level of 1,0 NTU in accordance with EN ISO 7027.

Aluminium25
Ammonium40
Antimony40
Arsenic30
Benzene40
Benzo(a)pyrene(2)50
Boron25
Bromate40
Cadmium25
Chloride15
Chromium30
Conductivity20
Copper25
Cyanide(3)30
1,2-dichloroethane40
Fluoride20
Hydrogen ion concentration pH (expressed in pH units)0.2
Iron30
Lead25
Manganese30
Mercury30
Nickel25
Nitrate15
Nitrite20
Oxiedisability(4)50
Pesticides(5)30
Polycyclic aromatic hydrocarbons(6)50
Selenium40
Sodium15
Sulphate15
Tetrachloroethene(7)30
Trichloroethene(7)40
Trihalomethanes: total(6)40
Total organic carbon (TOC)(8)30
Turbidity(9)30