The Private Water Supplies (Wales) Regulations 2017

Regulations 2, 11, 12, 13, 18 and 19

SCHEDULE 1 E+W Concentrations or Values

PART 1 E+W Wholesomeness

Commencement Information

I1 Sch. 1 Pt. 1 in force at 20.11.2017, see reg. 1

TABLE A:

MICROBIOLOGICAL PARAMETERS

Prescribed concentrations or values Parameters	Maximum concentration or value	Units of Measurement
Escherichia coli (E. coli)	0	Number/100ml
Enterococci	0	Number/100ml
In the case of water in bottles or containers:
Escherichia coli (E.coli)	0	Number/250ml
Enterococci		Number/250ml
Pseudomonas aeruginosa	0	Number/250ml
Colony count 22ºC	100	Number/ml

TABLE B:

CHEMICAL PARAMETERS

Prescribed concentrations or values Parameters		Maximum concentration or value	Units of Measurement
(1) The parametric value refers to the residual monomer concentration in the water as calculated according to specifications of the maximum release from the corresponding polymer in contact with the water. This is controlled by product specification.
(2) See also the nitrate-nitrite formula in regulation 4(1)(c).
(3) For these purposes “Pesticides” means: organic insecticides organic herbicides organic fungicides organic nematocides organic acaricides organic algicides organic rodenticides organic slimicides related products (inter alia, growth regulators) and their relevant metabolites, degradation and reaction products. Only those pesticides likely to be present in a given supply need be monitored.
(4) “Pesticides total” means the sum of the concentrations of the individual pesticides detected and quantified in the monitoring process.
(5) The specified compounds are: benzo(b)fluoranthene benzo(k)fluoranthene benzo(ghi)perylene indeno(1,2,3-cd)pyrene. The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.
The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.
(6) The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.
(7) The specified compounds are: chloroform bromoform dibromochloromethane bromodichloromethane. The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.
The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.
Acrylamide (1)		0.10	µg/1
Antimony		5.0	µg/1
Arsenic		10	µg/1
Benzene		1.0	µg/1
Benzo(a)pyrene		0.010	µg/1
Boron		1.0	mg/1
Bromate		10	µg/1
Cadmium		5.0	µg/1
Chromium		50	µg/1
Copper		2.0	mg/1
Cyanide		50	µg/1
1.2 dichloroethane		3.0	µg/1
Epichlorohydrin(1)		0.10	µg/1
Fluoride		1.5	mg/1
Lead		10	µg/1 µg/1
Mercury		1.0	µg/1
Nickel		20	µg/1
Nitrate (2)		50	mg/l
Nitrite (2)		0.5 (or 0.1 in the case of treatment works)	mg/l
Pesticides (3)—	Aldrin	0.030	µg/1
	Dieldrin	0.030	µg/1
	Heptachlor	0.030	µg/1
	Heptachlor epoxide	0.030	µg/1
	Other pesticides	0.10	µg/1
	Pesticides total (4)	0.50	µg/1
Polycyclic aromatic hydrocarbons (5)		0.10	µg/1
Selenium		10	µg/1
Tetrachloroethene and Trichloroethene(6)		10	µg/1
Trihalomethanes: Total(7)		100	µg/1
Vinyl chloride(1)		0.50	µg/1

National requirements – Prescribed concentrations or values

Parameters	Maximum concentration or value	Units of Measurement
Aluminium	200	µg/1
Colour	20	mg/l Pt/Co
Iron	200	µg/1
Manganese	50	µg/1
Odour	Acceptable to consumers and no abnormal change
Sodium	200	mg/l
Taste	Acceptable to consumers and no abnormal change
Tetrachloromethane	3	µg/1
Turbidity	4	NTU

PART 2 E+W Indicator Parameters

Commencement Information

I2 Sch. 1 Pt. 2 in force at 20.11.2017, see reg. 1

TABLE C:

Prescribed concentrations, values or states

Parameters	Maximum concentration or value	Units of Measurement
(1) The water should not be aggressive.
(2) Only in the case of surface water or groundwater that has been influenced by surface water.
Ammonium	0.50	mg/l
Chloride(1)	250	mg/l
Clostridium perfringens (including spores)	0	Number/100ml
Coliform bacteria	0	Number/100ml (Number/250ml in the case of water put into bottles or containers)
Colony counts	No abnormal change	Number/ml at 22ºC
Conductivity(1)	2500	µS/cm at 20ºC
Hydrogen ion	9.5 (maximum)	pH value
	6.5 (minimum) (in the case of still water put into bottles or containers the minimum is 4.5)	pH value
Sulphate(1)	250	mg/l
Total organic carbon (TOC)	No abnormal change	mgC/l
Turbidity(2)	1	NTU

PART 3 E+W Radioactive substances parameters

Commencement Information

I3 Sch. 1 Pt. 3 in force at 20.11.2017, see reg. 1

TABLE D:

Prescribed values for radon, tritium and indicative dose of water intended for human consumption

Parameters	Maximum concentration or value	Units of Measurement
(1) Enforcement action by the local authority is deemed justified on radiological protection grounds without further consideration where radon concentrations exceed 1,000 Bq/1.
(2) If tritium concentration exceeds its parametric value, an investigation (which may include analysis) of the presence of artificial radionuclides must be carried out.
Indicative dose (for radioactivity)	0.10	mSv
Radon(1)	100	Bq/l
Tritium (for radioactivity)(2)	100	Bq/l