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

Regulations 2, 9, 18 and 26

SCHEDULE 2 E+W Monitoring

PART 1 E+W Monitoring for Group A parameters

Sampling E+W

1.—(1) A local authority must undertake monitoring for Group A parameters in accordance with this Part.

(2) “Monitoring for Group A parameters” means sampling for each parameter listed in column 1 of Table 1 in the circumstances listed in the corresponding entry for that parameter in column 2 of that Table, in order to—

(a) determine whether or not water complies with the concentrations or values in Schedule 1;

(b) provide information on the organoleptic and microbiological quality of the water; and

(c) establish the effectiveness of the treatment of the water, including disinfection.

Table 1

Group A parameters

Parameter	Circumstances
Aluminium	If used as a water treatment chemical
Ammonium	If chloramination is used
Clostridium perfringens (including spores)	Where the water originates from, or is influenced by, surface waters
Coliform bacteria	In all supplies
Colony counts	In all supplies
Colour	In all supplies
Conductivity	In all supplies
Escherichia coli (E. coli)	In all supplies
Hydrogen ion concentration	In all supplies
Iron	If used as a water treatment chemical
Manganese	Where the water originates from, or is influenced by, surface waters
Nitrate	If chloramination is used
Nitrite	If chloramination is used
Odour	In all supplies
Pseudomonas aeruginosa	Only in the case of water in bottles or containers
Taste	In all supplies
Turbidity	In all supplies

Commencement Information

I4 Sch. 2 para. 1 in force at 20.11.2017, see reg. 1

Frequency of sampling E+W

2.  Sampling for Group A parameters must be carried out at frequencies specified in Table 2.

Table 2

Sampling frequency for Group A parameters

Volume m3/day	Sampling frequency per year
≤10	1
˃ 10 ≤ 100	2
˃ 100 ≤ 1,000	4
˃ 1,000 ≤ 2,000	10
˃ 2,000 ≤ 3,000	13
˃ 3,000 ≤ 4,000	16
˃ 4,000 ≤ 5,000	19
˃ 5,000 ≤ 6,000	22
˃ 6,000 ≤ 7,000	25
˃ 7,000 ≤ 8,000	28
˃ 8,000 ≤ 9,000	31
˃ 9,000 ≤ 10,000	34
˃ 10,000	4 + 3 for each 1,000 m3/day of the total volume (rounding up to the nearest multiple of 1,000 m3/day)

Commencement Information

I5 Sch. 2 para. 2 in force at 20.11.2017, see reg. 1

PART 2 E+W Monitoring for Group B parameters

Sampling E+W

3.—(1) A local authority must undertake monitoring for Group B parameters in accordance with this Part.

(2) “Monitoring for Group B parameters” means sampling for each parameter listed in Part 1 or 2 of Schedule 1 (other than Group A parameters already being sampled under Part 1 of this Schedule)—

(a) in order to provide information necessary to determine whether or not the private water supply satisfies each concentration, value or state specified in either of those Parts of that Schedule; and

(b) if disinfection is used, to check that disinfection by-products are kept as low as possible without compromising the effectiveness of disinfection.

Commencement Information

I6 Sch. 2 para. 3 in force at 20.11.2017, see reg. 1

Frequency of sampling E+W

4.  Sampling for Group B parameters must be carried out at the frequencies specified in Table 3.

Table 3

Sampling frequency for Group B parameters

Volume m3/day	Sampling frequency per year
≤10	1
˃ 10 ≤ 3,300	2
˃ 3,300 ≤ 6,600	3
˃ 6,600 ≤ 100,00	4
˃ 10,000 ≤ 100,000	3 + 1 for each 10,000 m3/day of the total volume (rounding up to the nearest multiple of 10,000 m3/day)
˃ 100,000	10 + 1 for each 25,000 m3/day of the total volume (rounding up to the nearest multiple of 25,000 m3/day)

Commencement Information

I7 Sch. 2 para. 4 in force at 20.11.2017, see reg. 1

PART 3 E+W Minimum frequency for both monitoring for Group A parameters and monitoring for Group B parameters for water put into bottles or containers

Commencement Information

I8 Sch. 2 Pt. 3 in force at 20.11.2017, see reg. 1

Volumea of water produced in bottles or containers each day (m3)	Monitoring for Group A parameters: number of samples per year	Monitoring for Group B parameters: number of samples per year
≤10	1	1
˃ 10 ≤ 60	12	1
˃ 60	1 for each 5 m3/day of the total volume (rounding up to the nearest multiple of 5 m3/day)	1 for each 100 m3/day of the total volume (rounding up to the nearest multiple of 100 m3/day)
a The volumes are calculated as averages taken over a calendar year.

PART 4 E+W Variation of monitoring requirements for Group A and Group B parameters

Variation of sampling frequency E+W

5.—(1) A local authority may reduce the sampling frequencies required for a parameter (other than for Escherichia coli (E. coli)) under Part 1 or 2 of this Schedule provided that—

(a) the results from samples taken in respect of that parameter collected at regular intervals over the preceding 3 years are all at less than 60% of the parametric value;

(b) the results of a risk assessment are considered, and that risk assessment indicates that no factor can be reasonably anticipated to be likely to cause deterioration of the quality of the water for human consumption;

(c) data collected in the course of discharging its monitoring obligations under this Part are taken into account; and

(d) at least one sample is taken per year.

(2) A local authority may set a higher frequency for any parameter if it considers it appropriate taking into account the findings of any risk assessment.

Commencement Information

I9 Sch. 2 para. 5 in force at 20.11.2017, see reg. 1

Variation of parameters E+W

6.—(1) A local authority may cease to monitor a parameter (other than Escherichia coli (E. coli)) otherwise required to be monitored under Part 1 or 2 of this Schedule provided that—

(a) the results from samples taken in respect of that parameter collected at regular intervals over the preceding 3 years are all at less than 30% of the parametric value;

(b) the results of a risk assessment are considered, and that risk assessment indicates that no factor can be reasonably anticipated to be likely to cause deterioration of the quality of the water for human consumption; and

(c) data collected in the course of discharging its monitoring obligations under this Part are taken into account.

(2) A local authority may monitor for other properties, elements, organisms or substances not included as a parameter if it considers it appropriate taking into account the findings of any risk assessment.

Commencement Information

I10 Sch. 2 para. 6 in force at 20.11.2017, see reg. 1

Regulations 12 and 13

SCHEDULE 3 E+W Monitoring of radioactive substances

Radon E+W

1.—(1) In relation to the radon parameter in the radioactive substances parameters table, a local authority—

(a) must ensure that a representative survey is carried out in accordance with sub-paragraph (2) to determine the likelihood of a private water supply failing to comply with the relevant parametric concentration or value specified in the radioactive substances parameters table; and

(b) must carry out monitoring where there is reason to believe, on the basis of the results of the representative surveys or other reliable information, including any risk assessment carried out in accordance with regulation 6, that the parametric value for the radon parameter laid down in the radioactive substances parameters table might be exceeded.

(2) A representative survey must be designed in such a way—

(a) as to be capable of determining the scale and nature of likely exposure to radon in water intended for human consumption originating from different types of groundwater sources and wells in different geological areas; and

(b) that underlying parameters, especially the geology and hydrology of the area, radioactivity of rock or soil, and well type, can be identified and used to direct further action to areas of likely high exposure to radon.

Commencement Information

I11 Sch. 3 para. 1 in force at 20.11.2017, see reg. 1

Tritium E+W

2.—(1) In relation to the tritium parameter in the radioactive substances parameters table, a local authority—

(a) must carry out monitoring where an anthropogenic source of tritium or other artificial radionuclides is present within the catchment area and it cannot be shown on the basis of other surveillance programmes or investigations, including any risk assessment carried out in accordance with regulation 6, that the level of tritium is below the parametric value listed in the radioactive substances parameters table; and

(b) must carry out an investigation of the presence of other artificial radionuclides if the concentration of tritium exceeds the parametric value listed in the radioactive substances parameters table.

(2) Where monitoring is required by sub-paragraph (1)—

(a) it must be carried out at the frequencies as set out for monitoring for Group B parameters in Table 3 in Part 2 of Schedule 2; or

(b) it must (in the case of a private water supply falling within the scope of regulation 11(1)) be carried out at least every 5 years or more frequently if the risk assessment referred to under sub-paragraph (1)(a) shows this to be necessary.

Commencement Information

I12 Sch. 3 para. 2 in force at 20.11.2017, see reg. 1

Indicative Dose E+W

3.—(1) In relation to the indicative dose parameter in the radioactive substances parameters table, a local authority must carry out monitoring where a source of artificial radioactivity or elevated natural radioactivity is present and it cannot be shown on the basis of other surveillance programmes or investigations, including any risk assessment carried out in accordance with regulation 6, that the level of indicative dose is below the parametric value listed in the radioactive substances parameters table.

(2) Where monitoring is required by sub-paragraph (1) in relation to artificial radionuclides—

(a) it must be carried out at the frequencies as set out for monitoring for Group B parameters in Table 3 in Part 2 of Schedule 2; or

(b) it must (in the case of a private water supply falling within the scope of regulation 11(1)) be carried out at least every 5 years or more frequently if the risk assessment shows this to be necessary.

(3) Where monitoring is required by sub-paragraph (1) in relation to a source of elevated natural radioactivity—

(a) the local authority—

(i) may decide the frequency of monitoring in its area depending on the screening strategy adopted by the authority; and

(ii) must notify the Welsh Ministers in writing of its decision under sub-paragraph (i); and

(b) the frequency of monitoring decided under paragraph (a)(i) may vary from a single check measurement to the frequencies as set out for monitoring for Group B parameters in Table 3 in Part 2 of Schedule 2.

(4) Where a local authority decides under sub-paragraph (3) that a single check measurement for natural radioactivity is appropriate, the local authority must carry out a further check if any change occurs in relation to the private water supply which is likely to influence the concentrations of radionuclides in the supply.

Commencement Information

I13 Sch. 3 para. 3 in force at 20.11.2017, see reg. 1

Water treatment E+W

4.  Where treatment to reduce the level of radionuclides in a private water supply has been undertaken, the local authority must monitor the supply for total indicative dose, radon and tritium in accordance with the provisions of this Part and the frequencies as set out for monitoring for Group B parameters in Table 3 in Part 2 of Schedule 2 to verify the continued efficacy of that treatment.

Commencement Information

I14 Sch. 3 para. 4 in force at 20.11.2017, see reg. 1

Averaging E+W

5.  Where a parametric value in the radioactive substances parameters table is exceeded in relation to a particular sample taken by a local authority, the Welsh Ministers must specify, by notice in writing to the local authority, the extent of resampling necessary to ensure that the measured values are representative of an average activity concentration for a full year.

Commencement Information

I15 Sch. 3 para. 5 in force at 20.11.2017, see reg. 1

Regulations 13 and 14

SCHEDULE 4 E+W Sampling and analysis

PART 1 E+W General

Samples: general E+W

1.—(1) The local authority must ensure, so far as reasonably practicable, that the appropriate requirements are satisfied when—

(a) taking, handling, transporting and storing a sample required to be taken in accordance with this Schedule;

(b) analysing such a sample; or

(c) causing any such sample to be taken, handled, transported, stored or analysed.

(2) In this paragraph, “the appropriate requirements” means such of the following as are applicable—

(a) the sample is representative of the quality of the water at the time of sampling;

(b) the person taking a sample is subject to a system of quality control to an appropriate standard checked from time to time by a suitably accredited body;

(c) the sample is not contaminated when being taken;

(d) the sample is kept at such a temperature and in such conditions as secure that there is no material alteration of the concentration or value for the measurement or observation of which the sample is intended;

(e) the sample is analysed as soon as reasonably practicable after it has been taken—

(i) by, or under the supervision of, a person who is competent to perform that task; and

(ii) with the use of such equipment as is suitable for the purpose;

(f) the collection and transportation of samples, or measurements recorded by continuous monitoring must be subject to a system of quality control to an appropriate standard checked from time to time by a suitably accredited body.

(3) When undertaking the activity described in—

(a) sub-paragraph (1)(a), the local authority must demonstrate compliance with any of EN ISO/IEC 17024, EN ISO/EIC 17025, or another equivalent standard accepted at international level;

(b) sub-paragraph (1)(b), the local authority must demonstrate compliance with EN ISO/EIC 17025 or another equivalent standard accepted at international level.

(4) Implementation of the requirement in sub-paragraph (3)(a) may be delayed for a period of no more than 24 months beginning on the day on which these Regulations come into force.

(5) In this paragraph, “suitably accredited body” means any person accredited by the United Kingdom Accreditation Service(1).

Commencement Information

I16 Sch. 4 para. 1 in force at 20.11.2017, see reg. 1

Analysing samples: microbiological parameters E+W

2.  For each parameter specified in the first column of Table 1 in Part 2 of this Schedule the method of analysis is specified in the second column of that table.

Commencement Information

I17 Sch. 4 para. 2 in force at 20.11.2017, see reg. 1

Analysing samples: chemical and indicator parameters E+W

3.—(1) On or before 31 December 2019, the local authority may apply the method of analysis for chemical and indicator parameters in either sub-paragraph (3) or sub-paragraph (4).

(2) After 31 December 2019, the local authority must apply the method of analysis for chemical and indicator parameters in sub-paragraph (4).

(3) For each parameter specified in the first column of Table 2 in Part 2 of this Schedule the method is one that is capable of—

(a) measuring concentrations and values with the trueness and precision specified in the second and third columns of that table, and

(b) detecting the parameter at the limit of detection specified in the fourth column of that table.

(4) For each parameter specified in the first column of Table 3 in Part 2 of this Schedule the method is one that is capable of measuring concentrations equal to—

(a) the parametric value with a limit of quantification of 30% or less of the relevant parametric value (as contained in Schedule 1), and

(b) the uncertainty of measurement in the second column of that table.

(5) The method of analysis used for odour and taste parameters must be capable of measuring values equal to the parametric value with a precision of 1 dilution number at 25°C.

(6) For these purposes—

(a) “limit of detection” is—

(i) three times the relative within-batch standard deviation of a natural sample containing a low concentration of the parameter; or

(ii) five times the relative within-batch standard deviation of a blank sample;

(b) “precision” (the random error) is twice the standard deviation (within a batch and between batches) of the spread of results about the mean. Acceptable precision is twice the relative standard deviation. Further specifications are set out in ISO 17025;

(c) “trueness” (the systematic error) is the difference between the mean value of the large number of repeated measurements and the true value. Further specifications are set out in ISO 17025;

(d) “uncertainty of measurement” is a non-negative parameter characterising the dispersion of the quantity values being measured, based on the information used.

Commencement Information

I18 Sch. 4 para. 3 in force at 20.11.2017, see reg. 1

Authorisation of alternative methods of analysis E+W

4.—(1) The Welsh Ministers may authorise a method different from those set out in paragraph 3(2) or 3(3) if satisfied that it is at least as reliable.

(2) An authorisation may be time-limited and may be revoked at any time.

Commencement Information

I19 Sch. 4 para. 4 in force at 20.11.2017, see reg. 1

Sampling and analysis by persons other than local authorities E+W

5.—(1) A local authority may enter into an arrangement for any person to take and analyse samples on its behalf.

(2) A local authority must not enter into an arrangement under sub-paragraph (1) unless—

(a) it is satisfied that the task will be carried out promptly by a person competent to perform it, and

(b) it has made arrangements that ensure that any breach of these Regulations is communicated to it immediately, and any other result is communicated to it within 28 days.

Commencement Information

I20 Sch. 4 para. 5 in force at 20.11.2017, see reg. 1

PART 2 E+W Analytical methods

Commencement Information

I21 Sch. 4 Pt. 2 in force at 20.11.2017, see reg. 1

Table 1

Prescribed methods of analysis for microbiological parameters

Parameter	Method
Escherichia coli (E. coli)	EN ISO 9308-1 or EN ISO 9308-2
Enterococci	EN ISO 7899-2
Pseudomonas aeruginosa	EN-ISO 16266
Colony count 22°C — enumeration of culturable microorganisms	EN ISO 6222
Colony count 36°C — enumeration of culturable microorganisms	EN 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.
Aluminium	10	10	10
Ammonium	10	10	10
Antimony	25	25	25
Arsenic	10	10	10
Benzene	25	25	25
Benzo(a)pyrene	25	25	25
Boron	10	10	10
Bromate	25	25	25
Cadmium	10	10	10
Chloride	10	10	10
Chromium	10	10	10
Colour	10	10	10
Conductivity	10	10	10
Copper	10	10	10
Cyanide(1)	10	10	10
1.2-dichloroethane	25	25	10
Fluoride	10	10	10
Hydrogen ion concentration pH (expressed in pH units)	0.2	0.2
Iron	10	10	10
Lead	10	10	10
Manganese	10	10	10
Mercury	20	10	20
Nickel	10	10	10
Nitrate	10	10	10
Nitrite	10	10	10
Oxidisability(2)
Pesticides and related products(3)	25	25	25
Polycyclic aromatic hydrocarbons(4)	25	25	25
Selenium	10	10	10
Sodium	10	10	10
Sulphate	10	10	10
Tetrachloroethene(5)	25	25	10
Tetrachloromethane	20	20	20
Trichloroethene(5)	25	25	10
Trihalomethanes: Total(4)
	25	25	10
Turbidity(6)	10	10	10
Turbidity(7)	25	25	25

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.
Aluminium	25
Ammonium	40
Antimony	40
Arsenic	30
Benzene	40
Benzo(a)pyrene(2)	50
Boron	25
Bromate	40
Cadmium	25
Chloride	15
Chromium	30
Conductivity	20
Copper	25
Cyanide(3)	30
1,2-dichloroethane	40
Fluoride	20
Hydrogen ion concentration pH (expressed in pH units)	0.2
Iron	30
Lead	25
Manganese	30
Mercury	30
Nickel	25
Nitrate	15
Nitrite	20
Oxiedisability(4)	50
Pesticides(5)	30
Polycyclic aromatic hydrocarbons(6)	50
Selenium	40
Sodium	15
Sulphate	15
Tetrachloroethene(7)	30
Trichloroethene(7)	40
Trihalomethanes: total(6)	40
Total organic carbon (TOC)(8)	30
Turbidity(9)	30

PART 3 E+W Monitoring for indicative dose and analytical performance characteristics

6.  A local authority may use reliable screening strategies to indicate the presence of radioactivity in water intended for human consumption. E+W

Commencement Information

I22 Sch. 4 para. 6 in force at 20.11.2017, see reg. 1

7.  The strategies referred to in paragraph 6 may include screening for— E+W

(a) certain radionuclides or individual radionuclide; or

(b) gross alpha activity or gross beta activity (where appropriate gross beta activity may be replaced by residual beta activity after subtraction of the K-40 activity concentration).

Commencement Information

I23 Sch. 4 para. 7 in force at 20.11.2017, see reg. 1

Screening for certain radionuclides, or screening for an individual radionuclide E+W

8.  If one of the activity concentrations exceeds 20% of the corresponding derived value or the tritium concentration exceeds its parametric value listed in Part 3 of Schedule 1 an analysis of additional radionuclides is required.

Commencement Information

I24 Sch. 4 para. 8 in force at 20.11.2017, see reg. 1

9.  A local authority must, in deciding which radionuclides require to be measured for each supply, take into account all relevant information about likely sources of radioactivity. E+W

Commencement Information

I25 Sch. 4 para. 9 in force at 20.11.2017, see reg. 1

Screening strategies for gross alpha activity and gross beta activity E+W

10.  Subject to paragraph 11 the recommended screening levels are—

(a) 0,1Bq/l for gross alpha activity; and

(b) 1,0Bq/l for gross beta activity.

Commencement Information

I26 Sch. 4 para. 10 in force at 20.11.2017, see reg. 1

11.  If the gross alpha activity exceeds 0,1Bq/l or the gross beta activity exceeds 1,0Bq/l, analysis for specific radionuclides is required. E+W

Commencement Information

I27 Sch. 4 para. 11 in force at 20.11.2017, see reg. 1

12.  The Welsh Ministers may set alternative screening levels for gross alpha activity and gross beta activity where it can be demonstrated by the local authority that the alternative levels are in compliance with an indicative dose of 0,1 mSv. E+W

Commencement Information

I28 Sch. 4 para. 12 in force at 20.11.2017, see reg. 1

Calculation of the indicative dose E+W

13.  The indicative dose must be calculated from—

[F1 (a) the measured radionuclide concentrations and the dose coefficients referred to as “standard values and relationships” in Article 13, and recommended for the estimation of doses from internal exposure in the definition of “standard values and relationships” in Article 4(96), of Council Directive 2013/59/Euratom laying down basic safety standards for protection against the dangers arising from exposure to ionising radiation; or]

(b) more recent information recognised by the Welsh Ministers, on the basis of the annual intake of water (730 1 for adults).

Textual Amendments

F1 Sch. 4 para. 13(a) substituted (28.3.2019) by The Rural Affairs, Environment, Fisheries and Food (Miscellaneous Amendments and Revocations) (Wales) Regulations 2019 (S.I. 2019/463), regs. 1(3), 29(3)

Commencement Information

I29 Sch. 4 para. 13 in force at 20.11.2017, see reg. 1

14.  Where the following formula is satisfied, it can be assumed that the indicative dose is less than the parametric value of 0,1 mSv and no further investigation is required— E+W

Derived concentrations for radioactivity in water intended for human consumption ⁽¹⁾

Origin	Nuclide	Derived concentration
(1) This table allows only for the radiological properties of uranium, not for its chemical toxicity.
Natural	U-2383	3,0 Bq/l
	U-2343	2,8 Bq/l
	Ra-226	0,5 Bq/l
	Ra-228	0,2 Bq/l
	Pb-210	0,2 Bq/l
	Po-210	0,1 Bq/l
Artificial	C-14	240 Bq/l
	Sr-90	4,9 Bq/l
	Pu-239/Pu-240	0,6 Bq/l
	Am-241	0,7 Bq/l
	Co-60	40 Bq/l
	Cs-134	7,2 Bq/l
	Cs-137	11 Bq/l
	1-131	6,2 Bq/l

Commencement Information

I30 Sch. 4 para. 14 in force at 20.11.2017, see reg. 1

Performance characteristics and methods of analysis E+W

15.  For the following parameters and radionuclides, the method of analysis used must, as a minimum, be capable of measuring activity concentrations with a limit of detection specified below:

Parameters and radionuclides	Limit of detection (Notes 1,2)	Notes
Tritium	10 Bq/l	Note 3
Radon	10 Bq/l	Note 3
gross alpha	0,04 Bq/l	Note 4
gross beta	0,4 Bq/l	Note 4
U-238	0,02 Bq/l
U-234	0,02 Bq/l
Ra-226	0,04 Bq/l
Ra-228	0,02 Bq/l	Note 5
Pb-210	0,02 Bq/l
Po-210	0,01 Bq/l
C-14	20 Bq/l
Sr-90	0,4 Bq/l
Pu-239/Pu-240	0,04 Bq/1
Am-241	0,06 Bq/l
Co-60	0,5 Bq/1
Cs-134	0,5 Bq/l
C2-137	0,5 Bq/l
1-131	0,5 Bq/1

Note 1: The limit of detection must be calculated according to the ISO standard 11929: Determination of the characteristic limits (decision threshold, detection limit, and limits of confidence interval) for measurements of ionising radiation — Fundamentals and application, with probabilities of errors of 1st and 2nd kind of 0,05 each.

Note 2: Measurement uncertainties must be calculated and reported as complete standard uncertainties, or as expanded uncertainties with an expansion factor of 1,96 according the ISO Guide for the Expression of Uncertainty in Measurement.

Note 3: The limit of detection for tritium and for radon is 10% of its parametric value of 100 Bq/1.

Note 4: The limit of detection for gross alpha activity and gross beta activities are 40% of the screening values of 0,1 and 1,0 Bq/1 respectively.

Note 5: This limit of detection applies only to initial screening for indicative dose for a new water source; if initial checking indicates that it is not plausible that Ra-228 exceeds 20% of the derived concentration, the limit of detection may be increased to 0,08 Bq/1 for routine Ra-228 nuclide specific measurements, until a subsequent re-check is required.

Commencement Information

I31 Sch. 4 para. 15 in force at 20.11.2017, see reg. 1

Regulation 16

SCHEDULE 5 E+W Records

Initial records E+W

1.—(1) A local authority must record the number of private water supplies in its area, and for each supply must record—

(a) the name of the supply, together with a unique identifier;

(b) the type of source;

(c) the geographical location using a grid reference;

(d) an estimate of the number of people supplied;

(e) an estimate of the average daily volume of water supplied in cubic metres;

(f) the type of premises supplied;

(g) detail of any treatment process, together with its location

(2) It must review and update the record at least once a year.

(3) It must keep the record for at least 30 years.

Commencement Information

I32 Sch. 5 para. 1 in force at 20.11.2017, see reg. 1

Additional records E+W

2.—(1) For each supply referred to in paragraph 1(1), the local authority must record, within 28 days of each of the following taking place—

(a) a plan and description of the supply;

(b) the monitoring programme for the supply;

(c) the risk assessment;

(d) a summary of the results of the risk assessment;

(e) a summary of the reasons for a decision to reduce or exempt altogether the monitoring of a particular parameter under Part 4 of Schedule 2;

(f) the date, results and location of any sampling and analysis relating to that supply, and the reason for taking the sample;

(g) the results of any investigation undertaken in accordance with these Regulations;

(h) any authorisation;

(i) any notices served under section 80 of the Act, or regulation 20;

(j) any action agreed to be taken by any person under these Regulations;

(k) any request for the local authority to carry out sampling and analysis, undertake a risk assessment or give advice;

(l) a summary of any advice given in relation to the supply.

(2) It must keep the risk assessment and records of sampling and analysis for at least 30 years, and all other records under this paragraph for at least 5 years.

Commencement Information

I33 Sch. 5 para. 2 in force at 20.11.2017, see reg. 1

Regulation 23

SCHEDULE 6 E+W Fees

Fee E+W

1.  The local authority may charge a fee, payable on invoice, for the activities in the following table, and the fee is the reasonable cost of providing the service subject to the following maximum amounts.

Service		Maximum fee (£)
(1) No fee is payable where a sample is taken and analysed solely to confirm or clarify the results of the analysis of a previous sample.
Risk assessment (each assessment):
	regulation 9 supply	700
	regulation 10 and 11 supplies	300
Sampling (each visit)(1)		100
Investigation (each investigation):		250
Granting an authorisation (each authorisation):		100
Analysing a sample—
	taken under regulation 10 or 11:	25
	taken during monitoring for Group A parameters:	110
	taken during monitoring for Group B parameters:	600

Commencement Information

I34 Sch. 6 para. 1 in force at 20.11.2017, see reg. 1

Persons liable to pay E+W

2.—(1) Any person requesting anything under these Regulations is liable for the cost.

(2) Except where sub-paragraph (1) applies, fees are payable, as specified in the invoice, by the relevant person.

(3) Where more than one person is liable, in determining who is required to make payment the local authority—

(a) may apportion the charge between them; and

(b) must have regard to any agreement or other document produced to the local authority relating to the terms on which water is supplied.

Commencement Information

I35 Sch. 6 para. 2 in force at 20.11.2017, see reg. 1

(1)

See S.I. 2009/3155 for the appointment of the United Kingdom Accreditation Service as the national accreditation body.