The Apique gold mine (06o 42´9.63”; -76o 09´15.66”; 1924 m.a.s.l.) is the oldest however the most technified, deepest, rich and exploited  in the Frontino gold district in Antioquia department of Colombia.  This was the main reason for the detailed studies performed in 2019  focusing on the radiological risk to miners caused by the 222Rn isotope and its alpha emitted progeny.

It was found that the Apique mine has an underground structure encompassing more than four exploitation mine galleries, with horizontal developments to the operating fronts up of 150 to 1,500 meters and vertical developments between galleries of -30 and -110 meters.  Physical parameters such like temperature, barometric pressure, wind and moisture are relatively stables, with external atmospheric temperatures oscillating between 31.2oC and 34.9oC and subsurface temperatures of 24.6oC in the upper mine gallery to 26.9oC in the deeper mine gallery. Relative humidity (Rh) was found between 74.8 to 85.2%.

Based on the 222Rn concentrations measured between 37 and 2,109 Bq·m-3 at different underground places, the number of labor hours of the miners, the equilibrium factor of 222Rn and its short-lived progeny, and considering the effects of internal parameters such as ventilation, humidity among others, the effective annual doses of exposure to ionizing radiation in different places in the mine were calculated, resulting in a maximum dose of 15,79 mSv·a-1, which is below the radiological safety in the colombian and international standards. As a reflection, when managed effectively, mining can protect health of workers and ecosystems, and support local socio-economic development.

  • Garzón, Gustavo; Argüelles, A., Londoño, J.I.