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Drinking Water Quality Standards

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Article 1


These Standards are determined pursuant to Article 11, Paragraph 2 of the Drinking Water Management Act (herein referred to as "this Act").


Article 2


These standards shall apply to drinking water supplied from drinking water equipment designated in Article 4 of this Act and other drinking water designated by the central competent authority.


Article 3


Regulations of these standards are set forth herein.
┌───────────┬────────┬─────────┐
│Item │Maximum limit │Unit │
├───────────┼────────┼─────────┤
│1. Coliform group │6 (Multiple-tube│Most probable │
│ │fermentation │number (MPN)/100 │
│ │method) │milliliters │
│ ├────────┼─────────┤
│ │6 (Membrane │Colony-forming │
│ │filtration │unit(CFU)/100 │
│ │method) │milliliters │
├───────────┼────────┼─────────┤
│2. Total bacterial │100 │Colony-forming │
│ count │ │unit(CFU)/millilit│
│ │ │ │
└───────────┴────────┴─────────┘

II. Physical standards:
┌───────────┬────────┬─────────┐
│Item │Maximum limit │Unit │
├───────────┼────────┼─────────┤
│1. Odor │3 │Threshold odor │
│ │ │number (TON) │
├───────────┼────────┼─────────┤
│2. Turbidity │2 │NTU (nephelometric│
│ │ │turbidity unit) │
├───────────┼────────┼─────────┤
│3. Color │5 │Platinum-cobalt │
│ │ │unit │
└───────────┴────────┴─────────┘

III. Chemical standards:
A. Substances that impact health:
┌───────────────────┬───────┬────────┐
│Item │Maximum limit │Unit │
├───────────────────┼───────┼────────┤
│1. Arsenic │0.01 │milligrams/liter│
├───────────────────┼───────┼────────┤
│2. Lead │0.01 │milligrams/liter│
├───────────────────┼───────┼────────┤
│3. Selenium │0.01 │milligrams/liter│
├───────────────────┼───────┼────────┤
│4. Total chromium │0.05 │milligrams/liter│
├───────────────────┼───────┼────────┤
│5. Cadmium │0.005 │milligrams/liter│
├───────────────────┼───────┼────────┤
│6. Barium │2.0 │milligrams/liter│
├───────────────────┼───────┼────────┤
│7. Antimony │0.01 │milligrams/liter│
├───────────────────┼───────┼────────┤
│8. Nickel │0.1 │milligrams/liter│
│ │ │ │
│ │0.07 │ │
│ │This standard │ │
│ │is effective │ │
│ │starting on │ │
│ │July 1, 2018. │ │
│ │ │ │
│ │0.02 │ │
│ │This standard │ │
│ │is effective │ │
│ │starting on │ │
│ │July 1, 2020. │ │
├───────────────────┼───────┼────────┤
│9. Mercury │0.002 │milligrams/liter│
│ │ │ │
│ │0.001 │ │
│ │This standard │ │
│ │is effective │ │
│ │starting on │ │
│ │July 1, 2020. │ │
├───────────────────┼───────┼────────┤
│10. Cyanide (as CN-) │0.05 │milligrams/liter│
├───────────────────┼───────┼────────┤
│11. Nitrite-nitrogen │0.1 │milligrams/liter│
├──────┬────────────┼───────┼────────┤
│Disinfection│12. Total │0.08 │milligrams/liter│
│byproducts │ Trihalomethanes │ │ │
│ ├────────────┼───────┼────────┤
│ │13. Haloacetic acids │0.060 │milligrams/liter│
│ │ (This concentration │ │ │
│ │ is defined as the │ │ │
│ │ sum of measured │ │ │
│ │ concentrations for │ │ │
│ │ five haloacetic │ │ │
│ │ acids, including │ │ │
│ │ monochloroacetic │ │ │
│ │ acid (MCAA), │ │ │
│ │ dichloroacetic acid │ │ │
│ │ (DCAA), │ │ │
│ │ trichloroacetic acid│ │ │
│ │ (TCAA), │ │ │
│ │ monobromoacetic acid│ │ │
│ │ (MBAA), and │ │ │
│ │ dibromoacetic acid.)│ │ │
│ ├────────────┼───────┼────────┤
│ │14. Bromate │0.01 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │15. Chlorite │0.060 │milligrams/liter│
│ │ (This regulation │ │ │
│ │ only applies to │ │ │
│ │ water supply systems│ │ │
│ │ that use gaseous │ │ │
│ │ chlorine dioxide as │ │ │
│ │ disinfectant) │ │ │
├──────┼────────────┼───────┼────────┤
│Volatile │16. Trichloroethene │0.005 │milligrams/liter│
│organic ├────────────┼───────┼────────┤
│compounds │17. Carbon tetrachloride│0.005 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │18. │0.20 │milligrams/liter│
│ │1,1,1-Trichloroethane │ │ │
│ ├────────────┼───────┼────────┤
│ │19. 1,2-Dichloroethane │0.005 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │20. Vinyl chloride │0.002 │milligrams/liter│
│ │ │ │ │
│ │ │0.0003 │ │
│ │ │This standard │ │
│ │ │is effective │ │
│ │ │starting on │ │
│ │ │July 1, 2018. │ │
│ ├────────────┼───────┼────────┤
│ │21. Benzene │0.005 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │22. 1,4-Dichlorobenzene │0.075 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │23. 1.1-Dichloroethylene│0.007 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │24. Dichloromethane │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │25. 1,2-Dichlorobenzene │0.6 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │26. Toluene │0.7 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │27. Xylenes │0.5 │milligrams/liter│
│ │ (This regulated │ │ │
│ │ concentration for │ │ │
│ │ Xylenes is defined │ │ │
│ │ as the sum of the │ │ │
│ │ measured │ │ │
│ │ concentrations of │ │ │
│ │ three xylene │ │ │
│ │ isomers, including │ │ │
│ │ 1,2-Xylene, │ │ │
│ │ 1,3-Xylene, and │ │ │
│ │ 1,4-Xylene.) │ │ │
│ ├────────────┼───────┼────────┤
│ │28. │0.07 │milligrams/liter│
│ │Cis-1,2-Dichloroethene │ │ │
│ ├────────────┼───────┼────────┤
│ │29. │0.1 │milligrams/liter│
│ │Trans-1,2-Dichloroethene│ │ │
│ ├────────────┼───────┼────────┤
│ │30. Tetrachloroethene │0.005 │milligrams/liter│
├──────┼────────────┼───────┼────────┤
│Agricultural│31. Endosulfan │0.003 │milligrams/liter│
│chemicals ├────────────┼───────┼────────┤
│ │32. Lindane │0.0002 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │33. Butachlor │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │34. │0.07 │milligrams/liter│
│ │Dichlorophenoxyacetic │ │ │
│ │acid │ │ │
│ ├────────────┼───────┼────────┤
│ │35. Paraquat │0.01 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │36. Methomyl │0.01 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │37. Carbofuran │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │38. Isoprocarb │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │39. Methamidophos │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │40. Diazinon │0.005 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │41. Parathion │0.02 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │42. EPN │0.005 │milligrams/liter│
│ ├────────────┼───────┼────────┤
│ │43. Monocrotophos │0.003 │milligrams/liter│
├──────┼────────────┼───────┼────────┤
│Persistent │44 Dioxin │3 │Petagram - World│
│organic │ This regulated │ │Health │
│pollutants │ concentration for │ │Organization - │
│ │ Dioxin is defined as │ │total toxicity │
│ │ the sum of the │ │equivalency │
│ │ measured │ │quantity/liter │
│ │ concentrations of 17 │ │(pg-WHO-TEQ/L) │
│ │ compounds, including │ │ │
│ │ 2,3,7,8- │ │ │
│ │ Tetrachlorinated │ │ │
│ │ dibenzo-p-dioxin-2,3 │ │ │
│ │ ,7,8-TeCDD, 2,3,7,8- │ │ │
│ │ Tetra chlorinated │ │ │
│ │ dibenzofuran,2,3,7,8-│ │ │
│ │ TeCDF and 2,3,7,8- │ │ │
│ │ penta-, hexa-, hepta-│ │ │
│ │ , and octa- │ │ │
│ │ chlorinated dioxins │ │ │
│ │ and furan. This │ │ │
│ │ regulated │ │ │
│ │ concentration for │ │ │
│ │ Dioxin is multiplied │ │ │
│ │ by the dioxin toxic │ │ │
│ │ equivalency factor │ │ │
│ │ (WHO-TEFs) provided │ │ │
│ │ by World Health │ │ │
│ │ Organization, and │ │ │
│ │ is expressed as a │ │ │
│ │ total toxicity │ │ │
│ │ equivalency │ │ │
│ │ quantity (TEQ). │ │ │
│ │ (If any drinking │ │ │
│ │ water treatment │ │ │
│ │ facilities locate │ │ │
│ │ within a 5-kilometer│ │ │
│ │ distance having a │ │ │
│ │ large pollution │ │ │
│ │ source, it must be │ │ │
│ │ monitored once every│ │ │
│ │ year. If the │ │ │
│ │ measured Dioxin │ │ │
│ │ concentrations do │ │ │
│ │ not exceed the │ │ │
│ │ maximum permitted │ │ │
│ │ limit for two │ │ │
│ │ consecutive years │ │ │
│ │ , the monitoring │ │ │
│ │ frequency may be │ │ │
│ │ reduced to once │ │ │
│ │ every two years │ │ │
│ │ starting in the │ │ │
│ │ following year.) │ │ │
└──────┴────────────┴───────┴────────┘

B. Substances with potential health impact:
┌────────────────┬────┬────────┐
│Item │Maximum │Unit │
│ │limit │ │
├────────────────┼────┼────────┤
│1. Flouride (as F-) │0.8 │milligrams/liter│
├────────────────┼────┼────────┤
│2. Nitrate nitrogen │10.0 │milligrams/liter│
├────────────────┼────┼────────┤
│3. Silver │0.05 │milligrams/liter│
├────────────────┼────┼────────┤
│4. Molybdenum │0.07 │milligrams/liter│
│(This regulation only applies to│ │ │
│water supply systems with a │ │ │
│potential pollution source, such│ │ │
│as those with semiconductor │ │ │
│fabrication plants, │ │ │
│optoelectronic manufacturing │ │ │
│plants, or parts manufacturing │ │ │
│plants, located within a │ │ │
│5-kilometer distance upstream │ │ │
│from their water intake. The │ │ │
│testing frequency is once per │ │ │
│quarter. If the test values do │ │ │
│not exceed the maximum │ │ │
│permissible limits for two │ │ │
│consecutive years, the testing │ │ │
│frequency could reduce to once │ │ │
│per year from the following │ │ │
│year.) │ │ │
├────────────────┼────┼────────┤
│5. Indium │0.07 │milligrams/liter│
│(This regulation only applies to│ │ │
│water supply systems with a │ │ │
│potential pollution source, such│ │ │
│as those with semiconductor │ │ │
│fabrication plants, │ │ │
│optoelectronic manufacturing │ │ │
│plants, or parts manufacturing │ │ │
│plants, located within a │ │ │
│5-kilometer distance upstream │ │ │
│from their water intake The │ │ │
│testing frequency is once per │ │ │
│quarter. If the test values do │ │ │
│not exceed the maximum │ │ │
│permissible limits for two │ │ │
│consecutive years, the testing │ │ │
│frequency could reduce to once │ │ │
│per year from the following │ │ │
│year.) │ │ │
│ │ │ │
└────────────────┴────┴────────┘

C. Contaminants that cause aesthetic, cosmetic, and technical effects:
┌─────────────┬───────┬────────┐
│Item │Maximum limit │Unit │
│ │ │ │
├─────────────┼───────┼────────┤
│1. Iron │0.3 │milligrams/liter│
├─────────────┼───────┼────────┤
│2. Manganese │0.05 │milligrams/liter│
├─────────────┼───────┼────────┤
│3. Copper │1.0 │milligrams/liter│
├─────────────┼───────┼────────┤
│4. Zinc │5.0 │milligrams/liter│
├─────────────┼───────┼────────┤
│5. Sulfate (as SO4-2) │250 │milligrams/liter│
├─────────────┼───────┼────────┤
│6. Phenols │0.001 │milligrams/liter│
├─────────────┼───────┼────────┤
│7. Anionic surface-active │0.5 │milligrams/liter│
│ agents │ │ │
├─────────────┼───────┼────────┤
│8. Chloride (as Cl) │250 │milligrams/liter│
├─────────────┼───────┼────────┤
│9. Ammonia nitrogen │0.1 │milligrams/liter│
├─────────────┼───────┼────────┤
│10. Total hardness as │300 │milligrams/liter│
│ CaCO3 │ │ │
├─────────────┼───────┼────────┤
│11. Total dissolved solids│500 │milligrams/liter│
├─────────────┼───────┼────────┤
│12. Aluminum │0.3 │milligrams/liter│
│(This regulation │ │ │
│concentration is defined │0.2 │ │
│as the concentration of │This standard │ │
│total aluminum.) │is effective │ │
│ │starting on │ │
│ │July 1, 2019. │ │
│ │ │ │
│ │(This │ │
│ │regulation is │ │
│ │not applicable│ │
│ │when the │ │
│ │turbidity of │ │
│ │the water │ │
│ │source is over│ │
│ │500 NTU in the│ │
│ │period of │ │
│ │typhoon │ │
│ │landfall │ │
│ │warning, and │ │
│ │when the │ │
│ │turbidity of │ │
│ │water source │ │
│ │is over 1000 │ │
│ │NTU during the│ │
│ │three days │ │
│ │after the │ │
│ │warning is │ │
│ │lifted.) │ │
└─────────────┴───────┴────────┘

D. Limit range of residual chlorine (Limited to water supply systems using chlorine as disinfectant):
┌────────────────┬────┬────────┐
│Item │Maximum │Unit │
│ │limit │ │
├────────────────┼────┼────────┤
│Free available residual chlorine│0.2-1.0 │milligrams/liter│
└────────────────┴────┴────────┘

E. Range for pH index (water treated by stationary continuous water supply equipment on public or private premises are not be subjected to this limitation):
┌────────────────┬────┬────────┐
│Item │Maximum │Unit │
│ │limit │ │
├────────────────┼────┼────────┤
│Hydrogen ion concentration index│6.0-8.5 │No unit │
│(pH value) │ │ │
└────────────────┴────┴────────┘


Article 4


For tap water, small water treatment facilities, and community-installed public water supply systems, when source water turbidity values exceed 1,500 NTU caused by torrential rains or other natural disasters, the maximum turbidity limit for drinking water may apply to 4 NTU.
Drinking water source turbidity testing data in the foregoing paragraph shall be provided by tap water enterprises, small water treatment units or community-installed public water supply units.


Article 5


For tap water, small water treatment facilities, and community-installed public water supply systems, when source water turbidity values exceed 1,500 NTU caused by torrential rains or other natural disasters, the limit range of free available residual chlorine may apply to follow values (shall apply only to water supply systems that add chlorine disinfectants).
┌────────────────┬───────┬─────┐
│Item │Limit range │Unit │
├────────────────┼───────┼─────┤
│Free available residual chlorine│0.2-2.0 │milligrams│
└────────────────┴───────┴─────┘


Article 6


(Deleted)


Article 7


Testing methods for each water quality item designated in these Standards shall be designated and officially announced by the central competent authority.


Article 8


A competent authority that conducts water quality analysis in accordance with these Standards may commission an approved analysis laboratory to assist with analysis.


Article 9


Unless an implementation date is separately designated, the regulation items in these standards shall take effect on the date of promulgation.