5 Colo. Code Regs. § 1002-41.8
The provisions of these regulations are severable, and if any provisions or the application of the provisions to any circumstances is held invalid, the application of such provision to other circumstances, and the remainder of these regulations, shall not be affected thereby.
TABLE 1
TABLE 1 Domestic Water Supply - Human Health Standards | |
Parameter | STANDARD1 |
Biological | |
Total Coliforms (30 day average) | 2.2 aorg/100 ml |
Total Coliforms (max in 30 days) | 23org/100 ml |
Inorganic | |
Antimony (Sb)d, M | 0.006 mg/l |
Asbestos M | 7,000,000 fibers/Liter |
Arsenic (As)d, M | 0.01 mg/l |
Barium (Ba)d, M | 2.0 mg/l |
Beryllium (Be)d, M | 0.004 mg/l |
Cadmium (Cd)d, M | 0.005 mg/l |
Chromium (Cr)c, d, M | 0.1 mg/l |
Cyanide [Free] (CN)M | 0.2 mg/l |
Fluoride (F)d, M | 4.0 mg/l |
Lead (Pb)d | 0.05 mg/l |
Mercury (inorganic) (Hg)d, M | 0.002 mg/l |
Molybdenum (Mo) d | 0.21 mg/l |
Nickel (Ni)d | 0.1 mg/l |
Nitrate (NO3)d, M | 10.0 mg/l as N |
Nitrite (NO2)d, M | 1.0 mg/l as N |
Total Nitrate+Nitrite (NO2+NO3)d, f | 10.0 mg/l as N |
Selenium (Se)d, M | 0.05 mg/l |
Silver (Ag)d | 0.05 mg/l |
Thallium (Tl)d, M | 0.002 mg/l |
Uranium (U) d, 2 | 0.0168 to 0.03M mg/l |
Radiologicalb, d | |
Gross Alpha Particle Activityi, M | 15 pCi/l |
Beta and Photon Emitterse | 4 mrem/year |
TABLE 2 Domestic Water Supply - Drinking Water Standards
Parameter | Standard |
Chlorophenol | 0.0002 mg/l |
Chloride (Cl)d | 250 mg/l |
Color | 15 color units |
Copper (Cu)d | 1 mg/l |
Corrosivity | Noncorrosive |
Foaming Agents | 0.5 mg/l |
Iron (Fe)d | 0.3 mg/l |
Manganese (Mn)d | 0.05 mg/l |
Odor | 3 threshold odor numbers |
pH | 6.5 - 8.5 |
Phenol | 0.3 mg/l |
Sulfate (SO 4)d | 250 mg/l |
Zinc (Zn)d | 5 mg/l |
TABLE 3 Agricultural Standards
Parameter | Standard |
Aluminum (Al)d , f | 5 mg/l |
Arsenic (As)d | 0.1 mg/l |
Beryllium (Be)d | 0.1 mg/l |
Boron (B)d, g | 0.75 mg/l |
Cadmium (Cd)d | 0.01 mg/l |
Chromium (Cr)d | 0.1 mg/l |
Cobalt (Co)d | 0.05 mg/l |
Copper (Cu)d | 0.2 mg/l |
Fluoride (F)d | 2 mg/l |
Iron (Fe)d | 5 mg/l |
Lead (Pb)d, f | 0.1 mg/l |
Lithium (Li)d, h | 2.5 mg/l |
Manganese (Mn)d, j | 0.2 mg/l |
Mercury (Hg)d, f | 0.01 mg/l |
Nickel (Ni)d | 0.2 mg/l |
Nitrite (NO2)d, f | 10 mg/l as N |
Nitrite & Nitrate (NO2+NO3)d, f | 100 mg/l as N |
Selenium (Se)d | 0.02 mg/l |
Vanadium (V)d | 0.1 mg/l |
Zinc (Zn)d | 2 mg/l |
pH | 6.5 - 8.5 |
TABLE 4 TDS Water Quality Standards
Background TDS Value (mg/l) | Maximum Allowable TDS Concentrations |
0 - 500 | 400 mg/l or 1.25 times the background level, whichever is least restrictive |
501 - 10,000 | 1.25 times the background value |
10,001 or greater | No limit |
1 Chronic or 30-day standard based on information contained in EPA's Integrated Risk Information System (IRIS) using a 10-6 incremental risk factor.
2 Whenever a range of standards is listed and referenced to this footnote, the first number in the range is a strictly health-based value, based on the Commission's established methodology for human health-based standards. The second number in the range is a maximum contaminant level, established under the federal Safe Drinking Water Act that has been determined to be an acceptable level of this chemical in public water supplies, taking treatability and laboratory detection limits into account. The Commission intends that control requirements for this chemical be implemented to attain a level of ambient water quality that is at least equal to the first number in the range except as follows:
* Where groundwater quality exceeds the first number in the range due to a release of contaminants that occurred prior to September 15, 2012, (regardless of the date of discovery or subsequent migration of such contaminants) clean-up levels for the entire contaminant plume shall be no more restrictive than the second number in the range or the groundwater quality resulting from such release, whichever is more protective.
* Wherever the Commission has adopted alternative, site-specific standards for the chemical, the site-specific standards shall apply instead of these statewide standards.
The Commission does not intend the adoption of this range of standards to result in changes to clean-up requirements previously established by an implementing agency, unless such change is mandated by the implementing agency pursuant to its independent statutory authority.
a When the Membrane Filter Technique is used for analysis, the average of all samples taken within thirty days must be less than 1 organism per 100 milliliters of sample. When the Multiple Tube Fermentation Method is used for analysis, the limit is less than 2.2 org/100 ml.
b If the identity and concentration of each radionuclide in a mixture are known, the limiting value would be derived as follows: Determine, for each radionuclide in the mixture, the ratio between the quantity present in the mixture and the limit specified. The sum of such ratios for all radionuclides in the mixture shall not exceed "1" (i.e. unity). A radionuclide may be considered as not present in a mixture if the ratio of the concentration to the limit does not exceed 1/10 and the sum of such ratios for all radionuclides considered as not present in the mixture does not exceed 1/4.
c The chromium standard is based on the total concentration of both trivalent and hexavalent forms of dissolved chromium.
d Measured as dissolved concentration. The sample water shall be filtered through a 0.45 micron membrane filter prior to preservation. The total concentration (not filtered) may be required on a case-by-case basis if deemed necessary to adequately characterize the pollution caused by the activity for the protection of groundwater uses.
e If two or more radionuclides are present, the sum of their annual dose equivalent to the total body or to any organ shall not exceed 4 mrem per year. Except for Tritium and Strontium 90 the concentration of man-made radionuclides causing 4 mrem total body or organ dose equivalents shall be calculated on the basis of a 2 liter per day drinking water intake using the 168-hour data listed in "Maximum Permissible Body Burden and Maximum Permissible Concentration of Radionuclides in Air or Water for Occupational Exposure," NBS Handbook 69, as amended, August 1963, US Department of Commerce.
f These more stringent levels are necessary to protect livestock watering. Levels for parameters without this footnote are set to protect irrigated crops at the same level. Where a party can demonstrate that a livestock watering use of groundwater is not reasonably expected, the applicable standard for lead is 5.0 mg/l.
g This level is set to protect the following plants in ascending order of sensitivity: Pecan, Black Walnut, Persian (English) Walnut, Jerusalem Artichoke, Navy Bean, American Elm, Plum, Pear, Apple, Grape (Sultanina and Malaga), Kadota Fig, Persimmon, Cherry, Peach, Apricot, Thornless Blackberry, Orange, Avocado, Grapefruit, Lemon. Where a party can demonstrate that a crop watering use of groundwater is not reasonably expected, the applicable standard for boron is 5.0 mg/l.
h This level protects all crops, except citrus which do not grow in Colorado and therefore a more stringent level of protection is not required.
i The Gross Alpha Activity standard excludes alpha activity due to Radon and Uranium.
j This standard is only appropriate where irrigation water is applied to soils with pH values lower than 6.0.
M Drinking water MCL.
5 CCR 1002-41.8