Today, the problems of protecting workers against the dangers of ionizing radiation are less well understood in our African countries.However, it is useful to assess the level of risk of exposure to ionizing radiation for people working in artisanal mining areas; by the dust emanating from these mining areas which may contain natural radioactive elements within it, of telluric origin; and There is therefore a problem of radiation protection. To do our study properly, we started by taking environmental measurements of radioactivity on the entire Twilizembe site and on the five cobalt ore fillings stored on it, then we sampled on these embankments to carry out radiochemical analyzes with a view to assessing the level of radiation protection of people working on this site, based on the theory of physical phenomena of radioactive decays occurring in different radioactive filiations (natural radioactive family). Based on the results obtained, we notice that the uranium concentration values ​​are too low, but can have a negative impact on people in the future (in the case of stochastic effects) and hence the need to evaluate the others. aspects of exhibitions to be very precise and give a definitive conclusion to this work.

The risk factors of ionizing radiation on people working in the artisanal mining sector seem to be neglected due to the lack of information for workers in this trading center. These intense mining activities observed on the latter generate large quantities of aerosols in the environment due to the particle size reduction that takes place there and we note that inhalation and ingestion by the latter is inevitable; especially during the dry season; in addition, there is a risk of irradiation and contamination by radioelements which could be contained in the aerosols and which would cause transformations of certain organs of the body due to their levels of radiosensitivity. To this end, to have more details on the probability of the risk due to the contamination and the irradiation of these radioactive elements which would be contained in these aerosols, we have opted as a research technique based on observation, interview and questioning all the people working directly on this site as well as taking measurements of ambient radioactivity levels. The results obtained show that, in general, the values ​​of the ambient radioactivity levels taken are fair but exceed 0.5 µSv / h, which is the limit value accepted by ICRP 103 (international commission on radiological protection) for persons of public and published in 2007; and recommend a worker dosimetric monitoring program to prevent any risk of contamination and exposure.

The extraction of cobalt in the ore Kabolela, leads us to look for techniques and methods to extract a good amount of it (Cobalt) low cost without passing the gangue in the solution while minimizing costs . For this purpose to determine the leach parameters to recover the cobalt in the ore processed by the Company Kabolela BOSS MINING, we conducted experimental testing laboratory heap leach ore, preceded by size analyzes and granulochimiques different slices to determine the operating parameters can give satisfactory results. After collection, sifting and weighing of each particle size range for chemical analysis to determine the chemical distribution and know the slice that will allow good dissolution after leaching tests; we noticed that, in the same leaching time 48 hours, dissolution of metal in acid is a function of particle size. And to recover much of the metal, go to more than 48 hours and use a reducer solution to all Cobalt (divalent and trivalent).