Section NR 811.856 - Water treatment plant wastewater radionuclide content compliance with the unity equation 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.Wis. Admin. Code Department of Natural Resources § NR 811.856
CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (1) made under s. 13.92(4) (b) 7, Stats., Register November 2010 No. 659.Amended by, CR 22-074: r. and recr. (intro.), am. (2) (a) Register January 2024 No. 817, eff. 2/1/2024The 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.