Wisconsin Administrative Code
Department of Natural Resources
NR 800 - Environmental Protection - Water Supply
Chapter NR 811 - Requirements For The Operation And Design Of Community Water Systems
Subchapter XII - Waste Disposal
Section NR 811.856 - Water treatment plant wastewater radionuclide content compliance with the unity equation

Universal Citation: WI Admin Code § NR 811.856

Current through August 26, 2024

Water treatment plant wastewater containing radium or uranium shall not be discharged to a sanitary sewer or to waters of the state unless all of the following requirements are met:

(1) UNITY EQUATION. The levels of radium and uranium in the wastewater shall meet the limits of the Unity Equation as calculated based upon the requirements of the department of health services under s. DHS 157.30 (3) and Appendix E of ch. DHS 157.

(2) CALCULATIONS.

(a) Unity equation calculations in accordance with sub. (1) shall be performed for water treatment plants treating wells with combined radium-226 and radium-228, uranium, or both, exceeding the maximum contaminant level. The department may require unity equation calculations on a case-by-case basis if other radionuclides may be of concern.

(b) The water system owner or its consultant shall submit the Unity Equation assumptions and calculations to the department for review and approval before, or along with, the submission of plans and specifications to the department for the radionuclide removal water treatment equipment or plant.

(3) CORRECTIVE ACTIONS. Corrective action as approved by the department shall be taken, if necessary, to maintain the result of the Unity Equation calculations as less than one.

The department's Public Water Supply Section located in Madison may be contacted to obtain a copy of DNR Application of DHS Radionuclide Wastewater Disposal Criteria for help in addressing Unity Equation issues.

Disclaimer: These regulations may not be the most recent version. Wisconsin may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.

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