- Y Diweddaraf sydd Ar Gael (Diwygiedig)
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Dyma’r fersiwn wreiddiol (fel y’i gwnaed yn wreiddiol).
Regulations 2(12)
Item | Parameters | Specification concentration or Value (maximum unless otherwise stated) or State | Units of Measurement | Point of Monitoring |
---|---|---|---|---|
(*) May be monitored from samples of water leaving treatment works or other supply point, as no significant change during distribution. | ||||
(i) The water should not be aggressive. | ||||
(ii) Where radon concentrations exceed 1000Bq/l, remedial action shall be carried out on radiological protection grounds without further consideration. | ||||
(iii) Excluding tritium, potassium-40, radon, and radon decay products. | ||||
(iv) Elevated levels of tritium may indicate the presence of other artificial radionuclides. If the tritium concentration exceeds its parametric value, an analysis of the presence of other radionuclides shall be required. | ||||
(v) Where treatment to reduce the level of radionuclides in water intended for human consumption has been taken, monitoring must be carried out to ensure the continued efficacy of the treatment. | ||||
(vi) If the gross alpha activity exceeds 0.1Bq/l or gross beta activity exceeds 1.0Bq/l analysis for specific radionuclides is required.” | ||||
1 | Ammonium | 0.50 | mgNH4/l | Consumers’ taps |
2 | Chloride(i) | 250 | mgCl/l | Supply point(*) |
3 | Clostridium Perfringens (including spores) | 0 | Number/100ml | Supply point(*) |
4 | Coliform bacteria | 0 | Number/100ml | Consumers’ taps |
5 | Colony counts | No abnormal change | Number/1ml at 22oC Number/1ml at 37oC | Consumers’ taps, service reservoirs and treatment works |
6 | Conductivity(i) | 2500 | µS/cm at 20 oC | Supply point(*) |
7 | Hydrogen ion(i) | 9.5 6.5 (minimum) | pH value | Consumers’ taps |
8 | Radon (for radioactivity)(ii) (v) | 100 | Bq/l | Supply point(*) |
9 | Sulphate (i) | 250 | mgSO4/l | Supply point(*) |
10 | Indicative dose (for radioactivity)(iii) (v) (vi) | 0.10 | mSv | Supply point(*) |
11 | Total organic carbon (TOC) | No abnormal change | mgC/l | Supply point(*) |
12 | Tritium (for radioactivity)(iv) (v) | 100 | Bq/l | Supply point(*) |
13 | Turbidity | 1 | NTU | Treatment works |
Regulation 2(13)
Item | Parameter | Circumstances |
---|---|---|
1 | Aluminium | When used as a flocculant or where the water originates from, or is influenced by, surface waters. |
2 | Ammonium | |
3 | Clostridium pefringens (including spores) | Where the water originates from, or is influenced by, surface waters. |
4 | Coliform bacteria | |
5 | Colony Counts | |
6 | Colour | |
7 | Conductivity | |
8 | Escherichia coli (E.coli) | |
9 | Hydrogen ion | |
10 | Indicative Dose | Where treatment to reduce the level of radionuclides in water intended for human consumption has been taken. |
11 | Iron | When used as a flocculant or where the water originates from, or is influenced by, surface waters. |
12 | Manganese | Where the water originates from, or is influenced by, surface waters. |
13 | Nitrate | When chloramination is practised |
14 | Nitrite | When chloramination is practised |
15 | Odour | |
16 | Radon | Where treatment to reduce the level of radionuclides in water intended for human consumption has been taken. |
17 | Taste | |
18 | Tritium | Where treatment to reduce the level of radionuclides in water intended for human consumption has been taken. |
19 | Turbidity |
(1) Substances and parameters subject to monitoring | (2) Estimated population of water supply zone | (3) Reduced | (4) Standard |
---|---|---|---|
(*) Sampling for these parameters may be within water supply zones or at supply points as specified in Table 3, subject to notes (ii) and below (iii) below. | |||
(i) Where the population is not an exact multiple of 5,000, the population figure should be rounded up to the nearest multiple of 5,000. | |||
(ii) Check monitoring in water supply zones is required only where chloramination is practised. In other circumstances audit monitoring is required. | |||
(iii) Audit monitoring in water supply zones is required only where sodium hypochlorite is added after water has left the treatment works. In other circumstances, audit monitoring is required at supply points. | |||
(iv) To monitor for indicative dose (for radioactivity). | |||
(v) In the event that a single sample is taken in a year, a further sample should be taken if there is any change in relation to that supply that could affect the concentration of radionuclides in the water supply. | |||
Note: This table sets out the annual sampling frequencies for all the substances and parameters in column 1. These are determined for each water supply zone according to its estimated population (column 2). The number of samples is either the standard number in column 4 or the reduced number in column 3 (if one is given). Regulation 9 provides for the circumstances in which the reduced number of samples may be taken. | |||
Subject to check monitoring | |||
E.coli | <100 | 4 | |
Coliform bacteria | ≥100 | 12 per 5,000 population(i) | |
Residual disinfectant | |||
Aluminium | <100 | 1 | 2 |
Ammonium | 100-4,999 | 2 | 4 |
Clostridium perfringens (including spores)(*) | 5,000-9,999 | 6 | 12 |
Colony Counts | 10,000-29,999 | 12 | 24 |
Colour | 30,000-49,999 | 18 | 36 |
Conductivity(*) | 50,000-79,999 | 26 | 52 |
Hydrogen ion | 80,000-100,000 | 38 | 76 |
Iron | |||
Manganese | |||
Nitrate(ii) | |||
Nitrite(ii) | |||
Odour | |||
Taste | |||
Turbidity | |||
Subject to audit monitoring | |||
Aluminium | <100 | 1 | |
Antimony | 100-4,999 | 4 | |
Arsenic | 5,000-100,000 | 8 | |
Benzene(*) | |||
Benzo(a)pyrene | |||
Boron(*) | |||
Bromate(iii) | |||
Cadmium | |||
Chromium | |||
Clostridium perfringens (including spores) | |||
Copper | |||
Cyanide(*) | |||
1,2, dichloroethane(*) | |||
Enterococci | |||
Fluoride(*) | |||
Gross Alpha(*) (iv) (v) | |||
Gross Beta(*) (iv) (v) | |||
Iron | |||
Lead | |||
Manganese | |||
Mercury(*) | |||
Nickel | |||
Nitrate(ii) | |||
Nitrite(ii) | |||
Pesticides and related products(*) | |||
Polycyclic aromatic hydrocarbons | |||
Radon(*) | |||
Selenium | |||
Sodium | |||
Trichloroethene/ Tetrachloroethene(*) | |||
Tetrachloromethane(*) | |||
Trihalomethanes | |||
Chloride(*) | |||
Sulphate(*) | |||
Total Organic carbon(*) | |||
Tritium(*) |
(1) Item | (2) Substances and parameters | (3) Volume of water supplied m3/d | (4) Reduced | (5) Standard |
---|---|---|---|---|
(i) Check monitoring is required only in respect of surface waters (see regulation 6(2) and Table 1 in Schedule 3) | ||||
(ii) Sampling at treatment works when chloramination is practised. | ||||
(iia) Sampling at treatment works when chloramination is not practised. | ||||
(iii) Audit monitoring at supply points is required only where sodium hypochlorite is not added after water has left the treatment works. In other circumstances, audit monitoring is required in water supply zones. | ||||
(iv) To monitor for indicative dose (for radioactivity). | ||||
Note 1: Sampling is at treatment works for the substances and parameters shown in column (1) of Table 3 as items (1) to (6) and at supply points for the other substances and parameters, except nitrite subject to footnotes (ii) and (ii)(a) to the Table below. | ||||
Note 2: Table 3 sets out the annual sampling frequencies for all of the substances and parameters in column 2 at treatment works or supply points. The frequencies are determined according to the volume of water supplied at each treatment works or supply point (column 3). The number of samples is either the standard number in column 5 or the reduced number in column 4 (if one is given). Regulation 9 provides for the circumstances in which the reduced number of samples may be taken.” | ||||
1 | E.coli | <20 | - | 4 |
2 | Coliform bacteria | 20-1,999 | 12 | 52 |
3 | Colony counts | 2,000-5,999 | 52 | 104 |
4 | Nitrite(ii) | 6,000-11,999 | 104 | 208 |
5 | Residual disinfectant | ≥ 12,000 | 104 | 365 |
6 | Turbidity | |||
Subject to check monitoring | ||||
7 | Clostridium perfringens(i) | <20 | - | 2 |
8 | Conductivity | 20-999 | 2 | 4 |
1,000-1,999 | 6 | 12 | ||
2,000-5,999 | 12 | 24 | ||
6,000-9,999 | 18 | 36 | ||
10,000-15,999 | 26 | 52 | ||
16,000-32,999 | 52 | 104 | ||
33,000-49,999 | 78 | 156 | ||
50,000-67,999 | 104 | 208 | ||
68,000-84,999 | 130 | 260 | ||
85,000-101,999 | 156 | 312 | ||
102,000-119,999 | 183 | 365 | ||
120,000-241,999 | 365 | 730 | ||
242,000-484,999 | 730 | 1,460 | ||
485,000-728,999 | 1,095 | 2,190 | ||
8A | Indicative Dose (for radioactivity) | <20 | 1 | |
8B | Gross alpha(iv) | 20-999 | 4 | |
8C | Gross beta(iv) | 1,000-49,999 | 8 | |
8D | Radon | 50,000-89,999 | 12 | |
8E | Tritium | 90,000-299,999 | 24 | |
300,000-649,999 | 36 | |||
≥ 650,000 | 48 | |||
Subject to audit monitoring | ||||
9 | Benzene | <20 | 1 | |
10 | Boron | 20-999 | 4 | |
11 | Bromate(iii) | 1,000-49,999 | 8 | |
11A | Clostridium perfringens (including spores) | 50,000-89,999 | 12 | |
12 | Cyanide | 90,000-299,999 | 24 | |
13 | 1,2,dichloroethane | 300,000-649,999 | 36 | |
14 | Fluoride | ≥ 650,000 | 48 | |
15 | Mercury | |||
16 | Nitrite(iia) | |||
17 | Pesticides and related products | |||
18 | Trichloroethene/ Tetrachloroethene | |||
19 | Tetrachloromethane | |||
20 | Chloride | |||
21 | Sulphate | |||
22 | Total Organic Carbon | |||
22a | Radon | |||
23 | Tritium | |||
24 | Indicative Dose (for radioactivity) | |||
25 | Gross alpha(iv) | |||
26 | Gross beta(iv) |
Regulation 2(14)
1. A water undertaker may use a screening strategy for gross alpha and gross beta to monitor for the parametric indicator value for indicative dose (1). The recommended screening value for gross alpha is 0.1Bq/l and for gross beta is 1.0Bq/l.
If the gross alpha activity is less than 0.1Bq/l and the gross beta activity is less than 1.0Bq/l it may be assumed that the indicative dose is less than 0.1mSv and radiological investigation is not needed, unless it is known from the other sources of information that specific radionuclides are present in water that are liable to cause an excess of 0.1mSv. Where the screening values are exceeded then additional radiological investigation is required.
The radionuclides to be measured must be based on all relevant information about likely sources of radioactivity.
2. Calculation of the ID
The ID must be calculated from the measured radionuclide concentrations and the dose coefficients laid down in Annex III, Table A of Directive 96/29/Euratom or more recent information recognised by the Department, on the basis of the annual intake of water (730l) for adults. Where the following formula is satisfied, it can be assumed that the ID is less than the parametric value of 0.1mSv and no further investigation is required.
where
Ci(obs) = observed concentration of radionuclide i
Ci(der) = derived concentration of radionuclide i
n = number of radionuclides detected.
Derived concentrations for radioactivity in water for human consumption(1) | ||
---|---|---|
Origin | Nuclide | Derived concentration |
(1) This table includes values for the most common natural and artificial radionuclides; these are precise values, calculated for a dose of 0.1mSV, an annual intake of 730 litre and using the dose coefficients laid down in Annex III Table A of Directive 96/29/Euratom; derived concentration for other radionuclides can be calculated on the same basis, and values can be updated on the basis of more recent information recognised by the competent authorities. | ||
(2) This table allows only for the radiological properties of uranium, not for its chemical toxicity. | ||
Natural | U-238(2) | 3.0 Bq/l |
U-234(2) | 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 | |
I-131 | 6.2 Bq/l |
3. Performance characteristics and method of analysis.
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 (1) (2) |
---|---|
(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 the confidence interval) for measurements of ionising radiation– Fundamentals and application, with probabilities of error of 1st and 2nd kind of 0.05 each | |
(2) Measurement uncertainties must be calculated and reported as complete standard uncertainties or as expanded standard uncertainties with an expansion factor of 1.96 according to the ISO Guide for the Expression of Uncertainty in Measurement. | |
(3) The limit of detection for tritium and for radon is 10% of its parametric value of 100 Bq/l. | |
(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/l respectively. | |
(5) This limit of detection applies only to initial screening for ID 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/l for routine Ra-228 nuclide specific measurements until a subsequent re-check is required.” | |
Tritium | 10 Bq/l(3) |
Radon | 10 Bq/l(3) |
gross alpha activity | 0.04 Bq/l(4) |
gross beta activity | 0.4 Bq/l(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(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/l |
Am-241 | 0.06 Bq/l |
Co-60 | 0.5 Bq/l |
Cs-134 | 0.5 Bq/l |
Cs-137 | 0.5 Bq/l |
I-131 | 0.5 Bq/l |
Where appropriate gross beta activity may be replaced by residual beta activity after subtraction of the K-40 activity concentration.
Y Diweddaraf sydd Ar Gael (diwygiedig):Y fersiwn ddiweddaraf sydd ar gael o’r ddeddfwriaeth yn cynnwys newidiadau a wnaed gan ddeddfwriaeth ddilynol ac wedi eu gweithredu gan ein tîm golygyddol. Gellir gweld y newidiadau nad ydym wedi eu gweithredu i’r testun eto yn yr ardal ‘Newidiadau i Ddeddfwriaeth’.
Gwreiddiol (Fel y’i Deddfwyd neu y’i Gwnaed): Mae'r wreiddiol fersiwn y ddeddfwriaeth fel ag yr oedd pan gafodd ei deddfu neu eu gwneud. Ni wnaed unrhyw newidiadau i’r testun.
Explanatory Memorandum sets out a brief statement of the purpose of a Statutory Rule and provides information about its policy objective and policy implications. They aim to make the Statutory Rule accessible to readers who are not legally qualified and accompany any Northern Ireland Statutory Rule or Draft Northern Ireland Statutory Rule laid before the UK Parliament during the suspension of the Northern Ireland Assembly.
Gallwch wneud defnydd o ddogfennau atodol hanfodol a gwybodaeth ar gyfer yr eitem ddeddfwriaeth o’r tab hwn. Yn ddibynnol ar yr eitem ddeddfwriaeth sydd i’w gweld, gallai hyn gynnwys:
Defnyddiwch y ddewislen hon i agor dogfennau hanfodol sy’n cyd-fynd â’r ddeddfwriaeth a gwybodaeth am yr eitem hon o ddeddfwriaeth. Gan ddibynnu ar yr eitem o ddeddfwriaeth sy’n cael ei gweld gall hyn gynnwys:
liciwch ‘Gweld Mwy’ neu ddewis ‘Rhagor o Adnoddau’ am wybodaeth ychwanegol gan gynnwys