"Article 8. Water Quality Control Levels and Mandatory Analysis Parameters. Operational control (CO) and four water quality control levels are established, as well as the mandatory physicochemical and microbiological parameters that must be analyzed:
- a)Operational Control (CO): This control is the responsibility of the operating entities, for which they must periodically measure the parameters: turbidity, odor, and free residual chlorine. They must have the basic laboratory equipment for monitoring at each source or in the mixture of all sources and distribution network, and keep a control log. The alert values and maximum admissible values are indicated in cuadro 1 of anexo 1 of this decree. The sampling frequency and number of samples to be collected for physicochemical analyses are indicated in cuadro B.1 of anexo 2 of this regulation.
- b)First Level (N1): Corresponds to the basic control program, which consists of a sanitary inspection to evaluate the operation and maintenance at the source, storage, distribution of drinking water, and the determination of the following parameters: apparent color, conductivity, pH, odor, temperature, turbidity, fecal coliforms, Escherichia coli, and free or combined residual chlorine. The alert values and maximum admissible values are indicated in cuadro 2 of anexo 1 of this regulation. If the sanitary inspection performed by the Ministry of Health establishes other contamination risks, the necessary parameters must be added to the basic control program. The sampling frequency and number of samples to be collected for physicochemical and microbiological analyses are indicated in cuadro B.2 of anexo 2 of this regulation.
- c)Second Level (N2): Corresponds to an expanded program, which consists of a sanitary inspection to evaluate the operation and maintenance at the supply source and in the distribution network. At this level, the control parameters are: aluminum, calcium, chloride, copper, total hardness, fluoride, iron, magnesium, manganese, potassium, sodium, sulfate, and zinc. The alert values and maximum admissible values are indicated in cuadro 3 of anexo 1 of this decree.
- d)Third Level (N3): Corresponds to an advanced control program, which consists of a sanitary inspection to evaluate the operation and maintenance at the supply source and in the distribution network. The control parameters contemplated at this level are: ammonium, antimony, arsenic, cadmium, chromium, mercury, nickel, nitrate, nitrite, lead, and selenium. The alert values and maximum admissible values are indicated in cuadro 4 of anexo 1 of this decree.
- e)Fourth Level (N4): Corresponds to occasional programs executed due to special situations, emergencies, or because the sanitary inspection performed by the Ministry of Health identifies an imminent risk of water contamination. The values for alert and maximum admissible are indicated in cuadro 5 of anexo 1 of this decree. The frequency and number of samples to be collected for physicochemical and microbiological analyses shall be established by the Ministry of Health.
Other microorganisms according to cuadro 5 of anexo 1 of this decree and any other of importance for public health; as well as radioactive elements must be absent in the analyzed samples".
Cuadro 1: Water Quality Parameters.
Operational Control (CO)
| Acceptability Parameters | Unit | Alert Value (VA) | Maximum Admissible Value (VMA) |
|---|---|---|---|
| Turbidity | UNT | 1.0 | 5.0 |
| Odor | - | Acceptable | Acceptable |
| Free residual chlorine (a) | mg/L | 0.3 | 0.6 (b) (c) |
(a) ) For the free residual chlorine parameter, permissible ranges are established and not VA or VMA.
(b) A maximum free residual chlorine value of 0.8 mg/L shall be allowed in no more than 20% of the measured samples.
(c) In emergency situations classified as such by the Ministry of Health, a free residual chlorine concentration of 0.8 mg/L shall be allowed at the sampling points measured in the distribution network".
"Cuadro 2: Water Quality Parameters.
First Level (N1)
| PARAMETER | Unit | Alert Value (VA) | Maximum Admissible Value (VMA) |
|---|---|---|---|
| Apparent Color | U-Pt-Co | < 5 | 15(c) |
| Conductivity | μS/cm | 400 | - |
| Fecal coliform | NMP/100 ml or UFC/100 ml | Not detectable (c) | Not detectable (c) |
| Escherichia coli | NMP/100 ml or UFC/100 ml | Not detectable (c) | Not detectable (c) |
| Free residual chlorine (a) | mg/L | 0.3 | 0.6 (d,e) |
| Combined residual chlorine (a) (b) | mg/L | 1.0 | 1.8 |
| Turbidity | UNT | 1.0 | 5.0 |
| Odor | --- | Acceptable | Acceptable |
| Temperature (a) | °C | 18 | 30 |
| pH (a) | pH Value | 6.0 | 8.0 |
(a) For the parameters pH, temperature, free residual chlorine, and combined residual chlorine, permissible ranges are established and not VA or VMA.
(b)) Only in the case that the chlorine residual is found in combined form or chlorine is being dosed in the form of chloramine (chlorine-ammonia).
(c) Not detectable (N.D.): according to the detection limit of the Method.
(d) A maximum free residual chlorine value of 0.8 mg/L shall be allowed in no more than 20% of the measured samples.
(e) In emergency situations classified as such by the Ministry of Health, a free residual chlorine concentration of 0.8 mg/L shall be allowed at the sampling points measured in the distribution network".
"CUADRO 4. Water Quality Parameters Third Level (N3)
| PARAMETER | Alert Value (VA) mg/L | Maximum Admissible Value (VMA) mg/L |
|---|---|---|
| Ammonium (NH4+) | 0.05 | 0.5 |
| Antimony (Sb) | --- | 0.005 |
| Arsenic (As ) | --- | 0.01 |
| Cadmium (Cd ) | --- | 0.003 |
| Chromium (Cr ) | --- | 0.05 |
| Mercury (Hg) | --- | 0.001 |
| Nickel (Ni) | --- | 0.02 |
| Nitrate ( NO3-) | 25 | 50 |
| Nitrite (NO2- ) | --- | 0.1 |
| Lead ( Pb ) | --- | 0.01 |
| Selenium (Se) | --- | 0.01 |
" "CUADRO 5. Water Quality Parameters Fourth Level (N4)
| PESTICIDE RESIDUES | |
|---|---|
| PARAMETER | Maximum Admissible Value (VMA) μg/L |
| Pesticides. (a) | 0.1 |
| Organochlorine pesticides(b) | 0.03 |
| Total pesticides. (c) | 0.5 |
| (a) By "Pesticides" is meant: organic insecticides, organic herbicides, organic fungicides, organic nematocides, organic acaricides, organic algicides, organic rodenticides, organic molluscicides, related products (growth regulators), and their pertinent metabolites and degradation and reaction products. Only those pesticides that are likely to be present in a given supply need to be controlled. If they are present in the supply and the treatment system is implemented; these must be evaluated on a monthly frequency. | |
|---|---|
| (b) Substances whose use is prohibited in the country, but which, due to their persistence in Costa Rica, could be found in waters given their long half-life in the environment and their extensive use in previous eras. | |
| (c) By "Total pesticides" is meant the sum of all pesticides detected and quantified in the control procedure. | |
| ORGANIC SUBSTANCES | |
| PARAMETER | Maximum Admissible Value (VMA) μg/L |
| Chlorinated Alkanes | |
| Carbon tetrachloride | 2 |
| Dichloromethane | 20 |
| 1,2-dichloroethane | 30 |
| 1,1,1-trichloroethane | 2000 |
| Chlorinated Ethenes | |
| Vinyl Chloride | 5 |
| 1,1-dichloroethene | 30 |
| 1,2-dichloroethene | 50 |
| Trichloroethene | 70 |
| Tetrachloroethene | 40 |
| Aromatic Hydrocarbons | |
| Toluene | 700 |
| Xylenes | 500 |
| Ethylbenzene | 300 |
| Styrene | 20 |
| Benzo-alpha-pyrene | 0.7 |
| Benzene | 0.5 |
| Chlorinated Benzenes | |
| Monochlorobenzene | 300 |
| 1,2-dichlorobenzene | 1000 |
| 1,4-dichlorobenzene | 300 |
| Trichlorobenzenes | 20 |
| Other Organic Compounds | |
| di (2-ethylhexyl) adipate | 80 |
| di (2-ethylhexyl) phthalate | 8 |
| Acrylamide | 0.5 |
| Epichlorohydrin | 0.4 | |
|---|---|---|
| Hexachlorobutadiene | 0.5 | |
| EDTA | 200 | |
| Nitrilotriacetic acid | 200 | |
| Tributyltin oxide | 2 | |
| Total polycyclic aromatic hydrocarbons 0.2 | ||
| Total polychlorinated biphenyls | N.D | |
| OTHER PHYSICAL AND INORGANIC PARAMETERS | ||
| PARAMETER | Alert Value (VA) mg/L | Maximum Admissible Value (VMA) mg/L |
| Total dissolved solids | --- | 1000 |
| Hydrogen Sulfide (H2S ) | --- | 0.05 |
| Cyanide (CN-) | --- | 0.07 |
| DISINFECTANTS AND DISINFECTION BY-PRODUCTS | ||
| PARAMETER | Maximum Admissible Value (VMA) μg/L | |
| Disinfectants | ||
| Monochloramine | 4000 | |
| Disinfection by-products | ||
| a) Chlorophenols | ||
| 2,4,6-trichlorophenol | 200 | |
| Formaldehyde | 900 | |
| b) Trihalomethanes | ||
| Bromoform | 100 | |
| Dibromochloromethane | 100 | |
| Bromodichloromethane | 60 | |
| Chloroform | 200 | |
| c) Chlorinated Acetic Acids | ||
| Dichloroacetic acid | 50 | |
| Trichloroacetic acid | 100 | |
| Trichloroacetaldehyde/chloral hydrate | 100 | |
| d) Haloacetonitriles | ||
| Dichloroacetonitrile | 90 | |
| Dibromoacetonitrile | 100 | |
| Trichloroacetonitrile | ||
| e) Cyanogen chloride (as CN-) | 70 | |
| MICROORGANISMS | ||
| Microorganism | Genus and/or species | |
| Bacteria | Escherichia coli pathogenic strains | Absence |
| Salmonella spp | Absence | |
|---|---|---|
| Shigella spp | Absence | |
| Aeromonas hydrophila | Absence | |
| Campylobacter jejuni and C. coli | ||
| Yersinia enterocolitica | Absence | |
| Vibrio cholerae | Absence | |
| Toxic cyanobacteria | Absence | |
| Viruses | Enterovirus | Absence |
| Adenovirus | Absence | |
| Hepatitis A and E Virus | Absence | |
| Rotavirus | Absence | |
| Norovirus | Absence | |
| Protozoa Cysts or oocysts | Crypotosporidium parvum | |
| Entamoeba histolytica | Absence | |
| Giardia intestinalis | Absence | |
| Cyclospora cayetanensis | Absence | |
| Helminths Eggs | Intestinal nematodes | Absence |
" "ANEXO 2 Cuadro A. Control Levels and Parameter
| Parameters to include | Operational Control (CO) | First Level (N1) | Second Level (N2) | Third Level (N3) |
|---|---|---|---|---|
| A. Physicochemical | · Turbidity · Odor (a) · Free residual chlorine | · Apparent color. · Turbidity · Odor (a) · Temperature · pH · Conductivity | · Aluminum · Calcium · Chloride · Copper · Total Hardness · Fluoride · Iron | · Ammonium · Antimony · Arsenic · Cadmium · Chromium · Mercury · Nickel |
| · Free residual chlorine · Combined residual chlorine | · Magnesium · Manganese · Potassium · Sodium (Na+) · Sulfate (SO42-) · Zinc (Zn) | · Nitrate · Nitrite · Lead Selenium | ||
|---|---|---|---|---|
| B. Microbiological | · Fecal Coliform · E. coli |
(a) ) Qualitative assessment.
(b) Except for water in closed deposits".
"3. RESULTS OF THE OPERATIONAL CONTROL (measurements carried out by the Operating Entity.)
TABLE A. OPERATIONAL CONTROL MONITORING (CO) PARAMETERS Supply source Distribution network Alert Value (VA) Maximum admissible value (VMA)
| No. | Value | No. | Value | |||
|---|---|---|---|---|---|---|
| times | Average | times | Average | |||
| Turbidity | <1 | 5 | ||||
| Odor | Must be acceptable | Must be acceptable | ||||
| Free residual chlorine (mg/L) (a) | 0.3 | 0.6 (b) (c) |
(a) Free residual chlorine is measured only in the distribution network.
(b) A maximum free residual chlorine value of 0.8 mg/L shall be allowed in no more than 20% of the measured samples.
(c) In emergency situations classified as such by the Ministry of Health, a free residual chlorine concentration of 0.8 mg/L shall be allowed at the sampling points measured in the distribution network.
NOTE: when there is more than one (1) supply source, this table must be repeated for each one of them".
"4. RESULTS OF THE PHYSICOCHEMICAL AND MICROBIOLOGICAL ANALYSES MEASURED BY THE LABORATORY.
TABLE B. PHYSICOCHEMICAL ANALYSES OF THE FIRST LEVEL (N1)
| Apparent Color (U- Pt-Co) | < 5 | 15(a) | ||||||
|---|---|---|---|---|---|---|---|---|
| Turbidity (UNT) | < 1 | 5 | ||||||
| Odor | Must be acceptable | Must be acceptable | ||||||
| Temperature (°C) | 18 | 30 | ||||||
| pH | 6 | 8 | ||||||
| Conductivity (μS/cm) | 400 | --- |
NOTE: when there is more than one (1) supply source, this table must be repeated for each one of them.
Laboratory name: ______________________________________ Sanitary Operating Permit: ___________ Expiration Date:_______________________ Physicochemical analysis No.: ___________________________________ Analysis date: ____________________________________________ *Attach the originals of the laboratory analyses with the respective endorsement of the Colegio Federado de Químicos e Ingenieros Químicos de Costa Rica".
"TABLE D. CHEMICAL ANALYSIS SECOND LEVEL (N2) AND THIRD LEVEL (N3)
| Parameters (mg/L) | N.A | Supply source | Distribution network | Alert Value (mg/L) | Maximum Admissible Value (mg/L) |
|---|---|---|---|---|---|
| SECOND LEVEL (N2) | |||||
| Aluminum ( Al+3 ) | ----- | 0.2 | |||
| Calcium ( Ca+2 ) | ------ | 100 |
| Chloride ( Cl- ) | 25 | 250 | |||
|---|---|---|---|---|---|
| Copper ( Cu ) | 1 | 2 | |||
| Total Hardness (CaCO3 ) | 300 | 400 | |||
| Fluoride ( F- ) | ----- | 0.7 to 1.5(a) | |||
| Iron (Fe) | --- | 0.3(b) | |||
| Magnesium (Mg+2 ) | 30 | 50 | |||
| Manganese (Mn ) | 0.1 | 0.5(b) | |||
| Potassium (K+ ) | ---- | 10 | |||
| Sodium ( Na+ ) | 25 | 200 | |||
| Sulfate ( SO4-2 ) | 25 | 250 | |||
| Zinc ( Zn ) | --- | 3 | |||
| THIRD LEVEL (N3) | |||||
| Ammonium (NH4+ ) | 0.05 | 0.5 | |||
| Antimony (Sb) | --- | 0.005 | |||
| Arsenic (As ) | --- | 0.01 | |||
| Cadmium (Cd ) | --- | 0.003 | |||
| Chromium (Cr ) | --- | 0.05 | |||
| Mercury (Hg) | --- | 0.001 | |||
| Nickel (Ni) | --- | 0.02 | |||
| Nitrate ( NO3-) | 25 | 50 | |||
| Nitrite (NO2- ) | --- | 0.1 | |||
| Lead ( Pb ) | --- | 0.01 | |||
| Selenium (Se) | --- | 0.01 |
N.A. applies, meaning these analyses do not correspond to be done) (a) 1.5 mg/L for temperatures of (8 to 12)⁰ C and 0.7 mg/L for temperatures of (25 to 30)⁰ C.
(b) In groundwater, where these two metals are found, the VMA (Fe + Mn) is 0.3 mg/L.
NOTE: when there is more than one (1) supply source, this table must be repeated for each one of them.
Laboratory name: ________________________________________________ Sanitary Operating Permit: _____________ Expiration date:____________ Physicochemical analysis No.: _____________________________ Analysis date: _______________________________ *Attach the originals of the laboratory analyses with their respective endorsement of the Colegio Federado de Químicos e Ingenieros Químicos de Costa Rica".