Environmental impact assessment of uranium ore mining and radioactive waste around a storage centre from Mexico

¹ Radioactivity Surveillance Laboratory, Nuclear Research National Institute (ININ), AP. Post. 18-1027, 11801 Mexico D.F., Mexico, e-mail: migp@nuclear.inin.mx
² IGFUNAM, Ciudad Universitaria, 04510 Mexico, D.F., Mexico

Abstract

Uranium ore tailings and radioactive waste have been stored during four decades at the Mexican Storage Centre for Radioactive Waste (SCRW). An estimation of effective doses from sources of natural and artificial origin in the general population and workers is presented. The sampling points are located at the SCRW at a 200 m neighbouring zone of the site and at distant communities around SCRW (regional background). The effective gamma dose rates were estimated from measurements of radionuclide concentration in soil samples from 1991 to 2002. Doses from the outdoor and indoor inhalation of radon were also determined. Transfer factors for ²²⁶Ra, ²¹⁰Pb, ¹³⁷Cs and ⁴⁰K from soil to wild edible species have been used to estimate the contribution of wild local foods to the dietary intake and to assess the supplementary doses received due to internal irradiation. The effective dose via the different exposure pathways estimated in the population that would live at the future in the immediate SCRW vicinity was two times higher than for the regional background.