Natural occurring radionuclide waste in Spain: the Huelva phosphogypsum stacks case

In this paper, the historical evolution in the management of the wastes generated by one paradigmatic NORM industry devoted to the production of phosphoric acid by the so-called wet-acid method is detailed, demonstrating through experimental results the advances performed along the time in order to minimize their ecological and radiological impact. In addition, and also through experimental studies, it is demonstrated that although the controlled disposal of the mentioned residues is an acceptable management option, is not the optimal one, it is possible to find better alternatives, with an extremely limited radiological impact, as substitute of natural gypsum in cement manufacturing, amended of saline soils, improver of the physical properties of soils, or cover material that speeds the degradation of waste materials and extends the useful life of landfills. The main conclusions obtained from this particular study can be extrapolated to the majority of NORM industries. The recycling of at least a fraction of the NORM residues generated could lead to the production of some co-products with demanding markets, and very limited radiological impact, alternative that should be encouraged