Table A Check Monitoring: Type A Supplies
| Annual sampling frequency (iv)(v) | ||||
|---|---|---|---|---|
| Volume of water distributed or produced each day within a supply zone (m3) (ii)(iii) | ||||
(1) Item | (2) Parameter | (3) ≤100 Level 1 | (4) > 100– ≤1000 Level 2 | (5) > 1000 Level 3(i) |
| Notes: (i) The sampling frequency (X) shall be determined as X = 4 + (3 for each 1,000 m3/d and part thereof of the total volume). (ii) A supply zone is a geographically defined area within which water intended for human consumption comes from one or more sources and within which water quality may be considered as being approximately uniform. (iii) The volumes are calculated as averages taken over a calendar year or using consumption based on the number of inhabitants, assuming a water consumption rate of 200 l/day/capita. (iv) Values in (brackets) in columns (4) and (5) are reduced sampling frequencies which may be applied if– (a) the values of the results obtained from samples taken during a period of at least two successive years are constant and significantly better than the limits laid down in Schedule 1; and (b) no factor is likely to cause a deterioration of the quality of the water. (v) As far as possible, the number of samples should be distributed equally in time and location and should be representative of the quality of water consumed or available for consumption throughout the year. (vi) Necessary only when used as a flocculant. In all other cases the parameter will be sampled according to the frequency specified for audit monitoring (Table B of Schedule 2). (vii) Necessary only if the water originates from, or is influenced by, surface water. In all other cases the parameter will be sampled according to the frequency specified for audit monitoring (Table B of Schedule 2). (viii) Necessary only when chloramination is used as a disinfectant. In all other cases the parameter will be sampled according to the frequency specified for audit monitoring (Table B of Schedule 2). | ||||
| 1. | Aluminium (vi) | 1 | 4(2) | X(X/2) |
| 2. | Ammonium | 1 | 4(2) | X(X/2) |
| 3. | Clostridium perfringens (vii) (including spores) | 1 | 4 | X |
| 4. | Coliform bacteria | 1 | 4 | X |
| 5. | Colony counts | 1 | 4 | X |
| 6. | Colour | 1 | 4(2) | X(X/2) |
| 7. | Conductivity | 1 | 4(2) | X(X/2) |
| 8. | Escherichia coli (E.coli) | 1 | 4 | X |
| 9. | Hydrogen ion | 1 | (2) | X(X/2) |
| 10. | Iron (vi) | 1 | 4(2) | X(X/2) |
| 11. | Nitrite (viii) | 1 | 4(2) | X(X/2) |
| 12. | Odour | 1 | 4(2) | X(X/2) |
| 13. | Taste | 1 | 4(2) | X(X/2) |
| 14. | Turbidity | 1 | 4 | X |