Section DHS 157.96 - Requirements(1) MAXIMUM CONTAMINANT LEVELS. (a)Alpha activity.1. The maximum contaminant level for radium-226 and radium-228 in community water systems is 5 pCi/L.2. The maximum contaminant level for gross alpha particle activity in community water systems is15 pCi/L, including radium-226, but excluding radon and uranium.(b)Beta particle and photon radioactivity from man-made radionuclides in community water systems.1. The average annual concentration of beta particle and photon radioactivity from man-made radionuclides in drinking water may not produce an annual dose equivalent to the total body or any internal organ greater than 0.04 millisievert (4 millirem).2. Except for the radionuclides listed in Table DHS 157.96A, the concentration of man-made radionuclides causing 0.04 millisievert (4 millirem) 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 Burdens and Maximum Permissible Concentrations of Radionuclides in Air or Water for Occupational Exposure", National Council on Radiation Protection and Measurements Report No. 22. If 2 or more radionuclides are present, the sum of their annual dose equivalent to the total body or to any organ may not exceed 0.04 millisievert (4 millirem). Note: The publication "Maximum Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air or Water for Occupational Exposure" in the National Council on Radiation Protection and Measurements Report No. 22, is the same document as Handbook 69 published by the National Bureau of Standards and which the Department received permission from the Attorney General and the Legislative Reference on March 22, 1982 to incorporate into ch. HSS 157 by reference. The reference is no longer available through the federal government and the National Bureau of Standards no longer exists. However, the document may be consulted at the Department's Radiation Protection Section at 1 W. Wilson St. in Madison, WI or the Legislative Reference Bureau and may be ordered from: NCRP, 7910 Woodmont Avenue, Suite 800, Bethesda MD, 20814.
Table DHS 157.96A
Average Annual Concentrations Assumed to Produce a Total Body or Organ Dose of 0.04 Millisievert (4 Millirem)/Year
| Radionuclide | Critical Organ | pCi per liter |
| Tritium | Total body | 20,000 |
| Strontium-90 | Bone marrow | 8 |
(2) ANALYTICAL METHODS FOR RADIOACTIVITY IN WATER.(a)Standard radionuclide. The following methods used to measure radionuclides and specified in "Prescribed Procedures for Measurement of Radioactivity in Drinking Water" EPA-600/4-80- 032 shall be used to determine compliance with sub. (1), except in cases where alternative methods have been approved under sub. (4):1. Gross Alpha and Beta - Method 900.2. Gross Radium Alpha - Method 900.1.3. Radium-226 - Method 903.1.4. Radioactive Strontium - Method 905.6. Radioactive Cesium - Method 901.7. Uranium - Method 908 or 908.1. Note: The publication "Prescribed Procedures for Measurement of Radioactivity in Drinking Water," EPA-600 4-80-32, is on file in the Legislative Reference Bureau and the Secretary of State's Office and is available on-line at.
(b)Other radionuclides. When the identification and measurement of radionuclides other than those listed in par. (a) is required, the following references shall be used, except in cases where alternative methods have been approved under sub. (4): 1. Procedures for Radiochemical Analysis of Nuclear Reactor Aqueous Solutions, H.L. Krieger and S. Gold, EPA-R4-73-014, May 1973. 2. Section 4.5.4 of the Health and Safety Laboratory Procedure Manual pertaining to testing water, ERDA-HASL 300, 28 th Edition. Note: 1. The Procedures for Radiochemical Analysis of Nuclear Reactor Aqueous Solutions, H. L. Krieger and S. Gold, EPA-R4-73-014, May 1973, is available upon written request to: Department of Health Services, Radiation Protection Section, PO Box 2659, Madison WI 53701-2659.
2. The Health and Safety Laboratory Procedure Manual ERDA-HASL 300, 28th Edition, 1997, is available on-line at http://www.orau.org/ptp/PTP%20Library/library/DOE/eml/hasl300/HASL300TOC.htm or by ordering from: The Environmental Measurements Laboratory (EML), 201 Varick St, NY,NY 10014-4811.
(c)Sensitivity.1. For the purpose of monitoring radioactivity concentrations in drinking water, the required sensitivity of the radioanalysis is defined in terms of a detection limit. The detection limit shall be that concentration that may be counted with a precision of plus or minus 100% at the 95% confidence level, where 1.96 is the standard deviation of the net counting rate of the sample.2. To determine compliance with sub. (1) (a) 1., the detection limit may not exceed one pCi/L. To determine compliance with sub. (1) (a) 2., the detection limit may not exceed 3 pCi/L. 3. To determine compliance with sub. (1) (b), the detection limits may not exceed the concentrations listed in Table DHS 157.96B. Table DHS 157.96B
Detection Limits for Man-made Beta Particle and Photon Emitters
| Radionuclide | Detection Limit |
| Tritium | 1,000 pCi/L |
| Strontium-89 | 10 pCi/L |
| Strontium-90 | 2 pCi/L |
| Iodine-131 | 1 pCi/L |
| Cesium-134 | 10 pCi/L |
| Gross beta | 4 pCi/L |
| Other radionuclides | 1/10 of the applicable limit |
(d)Compliance. To judge compliance with the maximum contaminant levels listed in sub. (1), averages of data shall be used and shall be rounded to the same number of significant figures as the maximum contaminant level for the substance in question. (3) MONITORING FREQUENCY IN COMMUNITY WATER SYSTEMS.(a)Monitoring requirements for gross alpha particle activity, radium-226 and radium-228.1. Compliance with sub. (1) (a) shall be based on the analysis of an annual composite of 4 consecutive quarterly samples or the average of the analyses of 4 samples obtained at quarterly intervals.a. A gross alpha particle activity measurement may be substituted for the required radium-226 and radium-228 analyses provided that the measured gross alpha particle activity does not exceed 5 pCi/L at a confidence level of 95%, where 1.96 is the standard deviation of the net counting rate of the sample. In localities where radium-228 may be present in drinking water, the department may require radium-226 or radium-228 analyses or analyses of both when the gross alpha particle activity exceeds 2 pCi/L.b. When the gross alpha particle activity exceeds 5 pCi/L, the same or an equivalent sample shall be analyzed for radium-228.2. A supplier of water shall monitor water supplies at least once every 4 years following the procedure required by subd. 1. At the discretion of the department, when the record taken in conformance with subd. 1. establishes that the average annual concentration is less than half the maximum contaminant levels established by sub. (1) (a), analysis of a single sample may be substituted for the quarterly sampling procedure required by subd. 1. a. When ordered by the department, more frequent monitoring shall be conducted in the vicinity of mining or other operations that may contribute alpha particle radioactivity to either surface or groundwater sources of drinking water.b. A supplier of water shall monitor in conformance with subd. 1. within one year of the introduction of a new water source for a community water system. More frequent monitoring shall be conducted when ordered by the department if possible contamination or changes in the distribution system or treatment processing occur that may increase the concentration of radioactivity in finished water. c. A community water system using 2 or more sources having different concentrations of radioactivity shall monitor source water and water from a free-flowing tap when required by the department.d. Monitoring for compliance with sub. (2) (a) need not include radium-228 except when required by the department, provided that the average annual concentration of radium-228 has been assayed at least once using the quarterly sampling procedure required by subd. 1.e. A supplier of water shall conduct annual monitoring of any community water system in which the radium-226 concentration exceeds 3 pCi/L, when required by the department.3. If the average annual maximum contaminant level for gross alpha particle activity or total radium as set forth in sub. (1) (a) is exceeded, the supplier of a community water system shall give notice to the department under sub. (7) and notify the public as required by sub. (8). Monitoring at quarterly intervals shall be continued until the annual average concentration no longer exceeds the maximum contaminant level or until a monitoring schedule as a condition to a variance, exemption or enforcement action is no longer in effect. (b)Monitoring requirements for man-made radioactivity in community water systems.1. Community water systems using surface water sources and serving more than 100,000 persons and any other community water systems as are designated by the department shall be monitored for compliance with sub. (1) (b) by analysis of a composite of 4 consecutive quarterly samples or analysis of 4 quarterly samples. Compliance with sub. (1) (b) may be assumed without further analysis if the average annual concentration of gross beta particle activity is less than 50 pCi/L and if the average annual concentrations of tritium and strontium-90 are less than those listed in Table 157.96A, provided that if both radionuclides are present, the sum of their annual dose equivalents to bone marrow does not exceed 4 millirem. a. If the gross beta particle activity exceeds 50 pCi/L, an analysis of the sample shall be performed to identify the major radioactive constituents present. The appropriate organ and total body doses shall be calculated to determine compliance with sub. (1)(b). b. A supplier of water shall conduct additional monitoring, as required by the department, to determine the concentration of man-made radioactivity in principal watersheds designated by the department.c. At the discretion of the department, a supplier of water utilizing only groundwaters may be required to monitor for man-made radioactivity. 2. After the initial analysis required by subd. 1., a supplier of water shall monitor at least every 4 years following the procedure given in subd. 1.3. The supplier of any community water system designated by the department as utilizing water subject to contamination by effluents from nuclear facilities shall initiate quarterly monitoring for gross beta particle and iodine-131 radioactivity and annual monitoring for strontium-90 and tritium. a. Quarterly monitoring for gross beta particle activity shall be based on the analysis of monthly samples or the analysis of a composite of 3 monthly samples. If the gross beta particle activity exceeds 50 pCi/L, an analysis of the sample shall be performed to identify the major radioactive constituents present and the appropriate organ and total body doses shall be calculated to determine compliance with sub. (1) (b). b. For iodine-131, a composite of 5 consecutive daily samples shall be analyzed once each calendar quarter. As required by the department, more frequent monitoring shall be conducted when iodine-131 is identified in the finished water.c. Annual monitoring for strontium-90 and tritium shall be conducted by means of the analysis of a composite of 4 consecutive quarterly samples or analysis of 4 quarterly samples.d. Data obtained by the direct monitoring of water supplies in the areas surrounding nuclear facilities may be utilized by the supplier where the department determines such data is applicable to a particular community water system.4. If the average annual maximum contaminant level for man-made radioactivity specified in sub. (1) (b) is exceeded, the operator of a community water system shall give notice to the department under sub. (7) and to the public as required by sub. (8). Monitoring at monthly intervals shall be continued until the concentration no longer exceeds the maximum contaminant level or until a monitoring schedule as a condition to a variance, exemption or enforcement action becomes effective. (4) ALTERNATIVE ANALYTICAL TECHNIQUES. With the written permission of the department concurred in by the administrator of the U.S. environmental protection agency, an alternative analytical technique may be employed. An alternative technique shall be acceptable only if it is substantially equivalent to the prescribed test in sub. (1) in both precision and accuracy as it relates to the determination of compliance with any maximum contaminant level. The use of the alternative analytical technique may not decrease the frequency of monitoring required by sub. (3). (5) APPROVED LABORATORIES. For the purpose of determining compliance with this section, samples shall be considered only if the samples have been analyzed by a laboratory approved by the department.(6) MONITORING OF CONSECUTIVE PUBLIC WATER SYSTEMS. When a public water system supplies water to one or more other public water systems, the department of natural resources may modify the monitoring requirements imposed by this section if the interconnection of the systems justifies treating them as a single system for monitoring purposes. Any modified monitoring shall be conducted under a schedule specified by the department of natural resources and concurred in by the administrator of the U.S. environmental protection agency.(7) REPORTING REQUIREMENTS. (a)Routine reports. Except where a shorter reporting period is specified in this section, a supplier of water shall report the results of a test, measurement or analysis required to be made under this section to the department within 40 days following the test, measurement or analysis.(b)Noncompliance reporting. A supplier of water shall report to the department within 48 hours noncompliance with any provision of this section, including failure to comply with monitoring requirements.(c)Exceptions. A supplier of water is not required to report analytical results to the department when the department performs the analysis.(8) PUBLIC NOTIFICATION. Public notification shall be provided as prescribed in s. NR 809.833.(9) RECORD MAINTENANCE. A supplier of water shall maintain records as prescribed in s. NR 809.82.(10) VARIANCE AND EXEMPTIONS. Variances and exemptions may be granted from any requirement regarding a maximum contaminant level for radioactivity as prescribed in ss. NR 809.90 and 809.91.Wis. Admin. Code Department of Health Services DHS 157.96
CR 01-108: cr. Register July 2002 No. 559, eff. 8-1-02.Amended by, CR 20-067: am. (8) Register November 2021 No. 792, eff. 1/1/2022