Contrary to solid NORM where quantitative management criteria and limits are set, and only necessary interpretation must be done, NORM in liquid forms are not well regulated. In the most recent relevant European regulation, there were only qualitative requirements that oblige industry operators to apply some radiation protection measures when liquid NORMs are expected to occur, at least at the level of appropriate monitoring.
There are some references concerning naturally occurring radionuclides (NOR) in water intended for human consumption in the Council Directive 2013/51/EURATOM However, again no limits are expressed as definite radionuclide activity concentrations.
To avoid this situation, some efforts are expected to be spent on the development of internationally recognised scientific guidance enabling MS to use common attitude to liquid NORM management and control, including possible water treatment and purification.
You can download the introduction here.
Workshop agenda can be downloaded here