Water, a simple molecule which is essential for the life and development of the population. The distribution of this drinking water of good sanitary quality and the maintenance of the quality during its distribution is a permanent concern of REGIDESO (Water Distribution Authority). The quality aspect deserves special attention in terms of microbiological and physicochemical balance.The water from the Regideso; distributed in the town of Kolwezi to part of the population may have a poorer quality at the outlet of the tap compared to that produced in factories because of the dilapidated drinking water distribution network in the town.Thus our study will focus on the knowledge of the microbiological quality (mesophilic aerobic flora, total coliforms, Escherichia coli, salmonella and shigella, faecal streptococcus, clostridium perfringens) and physicochemical (pH, turbidity, residual chlorine, etc.) of the water, flowing from the Regideso tap. To do this, a research method and technique based on experimentation as well as documentation in order to compare the results obtained in the laboratory according to international standards for the quality of water intended for human consumption and carried out by the tests of 'guidelines for evaluating the final quality of water intended for human consumption. After the orientation tests focused on physico-chemical analyzes only. We carried out microbiological analyzes to identify pathogenic germs in the water of the factories as well as at the level of the distribution network for the proper assessment of the quality of the latter. After analysis, we found the following:- The physico-chemical analyzes of the water taken at the outlet of the treatment plants show values ​​below the limits of the standards published in 2011 by the WHO;- A deterioration in the quality of the water caused by the obsolescence (piping pierced in certain places and corrosion of the piping) of the distribution network at certain sampling points; this situation is observed in the MUNUNKA district located in the commune of MANIKA. The degradation influences the turbidity of the water drawn from the taps as well as the reduction in the concentration of the residual chlorine level (i.e. 12.40 NTU against the WHO standard: 0-5 NTU and 0.1 mg / l of Chlorine against the WHO standard: 0.2 - 1mg / l);- And finally, the microbiological analysis shows that there is an absence of all the pathogenic germs sought except in raw water which has an excess of aerobic mesophilic flora (ie 591 CFU / 100ml against the WHO standard: ˂ 100 ml). To maintain good water quality, REGIDESO will need substantial resources to rebuild its distribution network without forgetting the renewal of equipment.

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).

The extraction of metal ore in the poor leads us to look for techniques and methods to extract a good amount of it (metal) low cost without passing the gangue in the solution. For this purpose, to determine leaching parameters seen to recover the metal in a low grade ore, we proceeded to test leaching guidelines heap ore preceded by size analysis and chemical different slices to determine the working parameters that can give satisfactory results. After these analyzes guidance, we opted for crushing the ore to determine the correct job settings for a good recovery of the metal contained in the ore poor and know the slice for perfect contact between the etching solution and ore for metal recovery. During testing after leaching, we noticed that when we respect the following parameters: a constant acid concentration of 70 g / l, a time of 64 hours, a particle size of 1,700 micron; we dissolved a good amount of metals or a yield ranging between 37.9 to 74.9% when the particle size of the ore pass 9423-850 micron. However, leaching of the composite sample of the same ore, gives a neighbor leach performance to which is recorded with the fine ore 70.8%.