The COMINAK and SOMAIR mining sites are among the largest sites in the world for the extractionof uranium (U-238) and thorium (Th-232) metals. The average value of uranium U-238 and thoriumTh-232 concentrations from our measurement results carried out around these two sites are respectively 2.34 ppm and 11.7 ppm in the soils of the COMINAK mining area, compared to 1.35ppm and 7.85 ppm in the soils of the SOMAIR mining area. These average concentration values ​​are below the global normal value for U-238 which is 2.95 ppm (35 Bq/Kg), while they exceed the normal value for Th-232 which is (30 Bq/Kg) or 7.39 ppm in these two sites. To date, the exact value of the particulate and gaseous deposit (Ds) of the annual release of these metals into the soils of the COMINAK and SOMAIR mining areas is not known due to the different parameters. It is therefore necessary to carry out studies on the evolution of the input of these pollutants to the soil. Here, we study in recurrence, the evolution of the input Ds of the metals uranium (U-238) and thorium (Th-232) to the soil by mainly considering that the source of contamination is linked to the extraction of these metals in said sites in order to estimate the content of these metals in the years to come. It emerges from this study that: - For the COMINAK site which is shut down, the thorium concentration regularizes in 29 years if the shutdown is prolonged - if the extraction of these metals continues in these two sites, the increase in the content of these metals increases if the deposit Ds of the annual discharge of these metals exceeds a limit value discussed in this article according to the site and the nature of the metal considered. And this could have a harmful impact on the environment.
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