
1 

(1) The title of these Regulations is the Water Supply (Water Quality) (Amendment) Regulations 2016 and they come into force on 14 April 2016.
(2) In these Regulations, “the 2010 Regulations” means the Water Supply (Water Quality) Regulations 2010.
2 
In regulation 6 of the 2010 Regulations—
(a) in paragraph (6), omit the words “and, subject to paragraph (7), the parameters relevant to radioactivity (total indicative dose and tritium),”; and
(b) omit paragraphs (7) to (9).
3 
After regulation 6 of the 2010 Regulations, insert—“
6A 

(1) A water undertaker must monitor each water supply zone within its area of supply for the parameters contained in the radioactive substances parameters table in accordance with this regulation and Schedule 3A.
(2) In this regulation and Schedule 3A, “the radioactive substances parameters table” means the table in Schedule 2A.
(3) The Welsh Ministers may, by notice to a water undertaker, confirm that they have established (on the basis of representative surveys, monitoring data or other reliable information) that, for a period specified in the notice, one or more of the parameters listed in the radioactive substances parameters table is not likely to be present in a water supply zone for human consumption purposes in concentrations which could exceed the prescribed concentration or value for the relevant parameter in that table.
(4) Where a notice is given to a water undertaker under paragraph (3), the water undertaker is not required to monitor the water supply zone for the parameter (or parameters) during the period specified in the notice.
(5) Where paragraph (3) applies, the Welsh Ministers must communicate the grounds for their decision to the European Commission with the necessary documentation supporting the decision (including the findings of any surveys, monitoring or investigations carried out).
(6) Where a notice has previously been given under paragraph (3) and the Welsh Ministers are no longer satisfied that the levels of radon, tritium or the calculated ID in relation to the water supply zone specified in the notice will remain below the respective parametric values in the radioactive substances parameters table, the Welsh Ministers must inform the water undertaker in writing accordingly, and the exemption under paragraph (4) will no longer apply.
(7) In case of naturally occurring radionuclides, where previous monitoring results show that the concentration of radionuclides in the supply is stable, the minimum sampling and analysis frequencies are to be decided by the Welsh Ministers, and confirmed by notice in writing to the water undertaker, taking into consideration the risk to human health.
(8) The additional requirements in Schedule 5 apply to monitoring for compliance with the indicative dose parameter.”
4 
In the table in Schedule 2 to the 2010 Regulations, omit—
(a) the entry in relation to total indicative dose (for radioactivity);
(b) the entry in relation to tritium (for radioactivity); and
(c) note (ii).
5 
After Schedule 2 (indicator parameters) to the 2010 Regulations, insert the schedule set out in Schedule 1 to these Regulations.
6 
In Schedule 3 to the 2010 Regulations—
(a) in Table 2 (annual sampling frequencies: water supply zones) under the “subject to audit monitoring” heading—
(i) insert in the appropriate place —“
Radon(b)    ”
(ii) for the entries relating to gross alpha and gross beta, substitute—“
Indicative dose (for radioactivity)(b)    ”; and
(iii) omit note (v); and
(b) in Table 3 (annual sampling frequencies: treatment works or supply points) under the “subject to audit monitoring” heading—
(i) insert in the appropriate place—“
17A Radon   ”
(ii) for the entries relating to gross alpha and gross beta, substitute—“
Indicative dose (for radioactivity)(b)    ”; and
(iii) omit note (v).
7 
After Schedule 3 (monitoring) to the 2010 Regulations insert the schedule set out in Schedule 2 to these Regulations.
8 
After Schedule 4(analytical methodology) to the 2010 Regulations insert the schedule set out in Schedule 3 to these Regulations.
Carl Sargeant
Minister for Natural Resources, one of the Welsh Ministers
21 March 2016
SCHEDULE 1
Regulation 5
“
SCHEDULE 2A
Regulation 6A

Parameters Maximum concentration or value Units of measurement
Indicative dose (for radioactivity) 0,10 mSv
Radon 100 Bq/1
Tritium (for radioactivity) 100 Bq/l

”
SCHEDULE 2
Regulation 7
“
SCHEDULE 3A
Regulation 6A
1. 

(1) In relation to the radon parameter in the radioactive substances parameters table, a water undertaker—
(a) must ensure that a representative survey is carried out in accordance with sub-paragraph (2) to determine the likelihood of a 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 28, 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.
2. 

(1) In relation to the tritium parameter in the radioactive substances parameters table, a water undertaker—
(a) must carry out monitoring where an anthropogenic source of tritium or other artificial radionuclides is present within a water supply zone and it cannot be shown on the basis of other surveillance programmes or investigations, including any risk assessment carried out in accordance with regulation 28, 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) samples must be taken in accordance with regulation 9(1) and (3).
3. 

(1) In relation to the indicative dose (“ID”) parameter in the radioactive substances parameters table, a water undertaker must carry out monitoring where a source of artificial radioactivity or elevated natural radioactivity is present in a water supply zone and it cannot be shown on the basis of other surveillance programmes or investigations, including any risk assessment carried out in accordance with regulation 28, that the level of ID is below the parametric value listed the radioactive substances parameters table.
(2) Where monitoring is required by sub-paragraph (1) in relation to artificial radionuclides samples must be taken in accordance with regulation 9(1) and (3).
(3) Where monitoring is required by sub-paragraph (1) in relation to a source of elevated natural radioactivity—
(a) the Welsh Ministers must specify, by notice in writing to the water undertaker, the frequency of the monitoring required of—
(i) gross alpha activity;
(ii) gross beta activity; or
(iii) individual natural radionuclides,
depending on the screening strategy adopted by the water undertaker pursuant to Schedule 5; and
(b) the frequency of monitoring required under sub-paragraph (a) may vary from a single check measurement to the frequencies required for sampling in accordance with regulation 9(1).
(4) Where a single check for natural radioactivity is specified under paragraph (3)(a), the water undertaker must carry out a further check if any change occurs in relation to the supply which is likely to influence the concentrations of radionuclides in the supply.
4. 
Where treatment to reduce the level of radionuclides in a water supply zone has been undertaken, to verify the continued efficacy of that treatment, the water undertaker must—
(a) monitor the supply for total indicative dose, radon and tritium in accordance the provisions of this Schedule; and
(b) take samples in accordance with regulation 9(1) and (3).
5. 
Where a parametric value in the radioactive substances parameters table is exceeded in relation to a particular sample taken by a water undertaker, the Welsh Ministers must specify, by notice in writing to the water undertaker, the extent of resampling necessary to ensure that the measured values are representative of an average activity concentration for a full year.”
SCHEDULE 3
Regulation 8
“
SCHEDULE 5
Regulation 6A
1. 
A water undertaker may use reliable screening strategies to indicate the presence of radioactivity in water intended for human consumption.
2. 
The strategies referred to in paragraph 1 may include screening for–
(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).
3. 
If one of the activity concentrations exceeds 20% of the corresponding derived value or the tritium concentration exceeds its parametric value listed in Schedule 2A an analysis of additional radionuclides is required.
4. 
A water undertaker must, in deciding which radionuclides require to be measured for each supply, take into account all relevant information about likely sources of radioactivity.
5. 
Subject to paragraph 6 the recommended screening values are–
(a) 0,1Bq/l for gross alpha activity; and
(b) 1,0Bq/l for gross beta activity.
6. 
If the gross alpha activity exceeds 0,1Bq/l or the gross beta activity exceeds 1,0Bq/l, analysis for specific radionuclides is required.
7. 
The Welsh Ministers may set alternative screening levels for gross alpha activity and gross beta activity where it can be demonstrated by the water undertaker that the alternative levels are in compliance with an indicative dose of 0,1 mSv.
8. 
The radionuclides to be measured must be based on all relevant information about likely sources of radioactivity.
9. 
The indicative dose must be calculated from–
(a) the measured radionuclide concentrations and the dose coefficients laid down in Annex III, Table A of Directive 96/29/Euratom; or
(b) more recent information recognised by the Welsh Ministers, on the basis of the annual intake of water (730 1 for adults).
10. 
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–∑i=1nCi(obs)Ci(der)≤1where:
 Ci(obs) = observed concentration of radionuclide i
 Ci(der) = derived concentration of radionuclide i
 n = number of radionuclides detected.

Origin Nuclide Derived concentration
Natural 
U-238
 
3,0 Bq/1

 
U-234
 
2,8 Bq/1

 
Ra-226
 
0,5 Bq/1

 
Ra-228
 
0,2 Bq/1

 
Pb-210
 
0,2 Bq/1

 
Po-210
 
0,1 Bq/1

Artificial 
C-14
 
240 Bq/1

 
Sr-90
 
4,9 Bq/1

 
Pu-239/Pu-240
 
0,6 Bq/1

 
Am-241
 
0,7 Bq/1

 
Co-60
 
40 Bq/1

 
Cs-134
 
7,2 Bq/1

 
Cs-137
 
11 Bq/1

 
1-131
 
6,2 Bq/1



11. 
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/1
 
Note 3


Radon
 
10 Bq/1
 
Note 3


gross alpha
 
0,04 Bq/1
 
Note 4


gross beta
 
0,4 Bq/1
 
Note 4


U-238
 
0,02 Bq/1
 

U-234
 
0,02 Bq/1
 

Ra-226
 
0,04 Bq/1
 

Ra-228
 
0,02 Bq/1
 
Note 5


Pb-210
 
0,02 Bq/1
 

Po-210
 
0,01 Bq/1
 

C-14
 
20 Bq/1
 

Sr-90
 
0,4 Bq/1
 

Pu-239/Pu-240
 
0,04 Bq/1
 

Am-241
 
0,06 Bq/1
 

Co-60
 
0,5 Bq/1
 

Cs-134
 
0,5 Bq/1
 

Cs-137
 
0,5 Bq/1
 

I-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.”