Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

NORM sites are characterized by their waste type and by complex mixtures of different soil types, heavy metals, minerals, microbial diversities, present flora and fauna, as well as disequilibria in radionuclide decay chains. Due to this complexity, challenges arise not only from the lack of comprehensive scientific data, but also from existing model concepts themselves, which do not adequately describe the interplay between simultaneously occurring chemical and biological processes at a NORM site. Therefore, a promising strategy is to reduce modelling uncertainties by identifying and parameterizing the key processes that influence the radionuclide behaviour in these sites and to transfer this knowledge into mechanistic models sufficiently complex to describe the radionuclide behaviour in the environment, however, at the same time being simple enough to be practical and applicable to different NORM sites. In view of potential hazards associated with the exposure to enhanced natural radiation, proper evaluation of NORM sites related to former, current or future human activities, as well as the need for developing preventive methods at different stages of a technological process in a NORM industry are essential tasks here.
Working group (WG) NORM, currently composed of 20 organisations from 10 European countries, was established within the European Radioecology Alliance. One of the initial tasks of this WG was to develop a roadmap document, which covers a time frame of five years. This roadmap is part of a prolonged vision aiming at continuously incorporating new knowledge to progressively improve risk assessments of NORM contaminated sites and thereby helps to reduce the risk for humans and wildlife. The main objectives specified in the roadmap can be summarized as follows: (1.) improve risk assessment for existing and future NORM sites, (2.) extend transport modelling of radionuclides into the uncontaminated environments by including chemical/geochemical and biological/microbiological processes, i.e. to identify and mathematically describe processes that make significant contributions to the environmental transfer of radionuclides, and (3.) develop a mechanistic understanding of chemical and biological processes on a molecular scale and translate this knowledge into robust sub-models thus paving the way for new strategies for a sustainable rehabilitation and remediation of NORM sites.
WG NORM is a research platform for NORM interested scientists for sharing and exchanging knowledge on radionuclide behaviour in the environment. Its objectives aim at reducing the uncertainty of human and environmental risk assessment for NORM via an improved mechanistic process-based transport modelling and by integrating chemical process understanding as well as biological/microbiological processes in transport codes.