Analysis of physicochemical parameters (T°, pH, EC, ORP) and ETM along the Naviundu channel on the water and the sediment was made to establish a diagnosis of the state of surface water of the river downstream of the plant hydrometallurgical Chemical of Africa (CHEMAF). Thus, samples were taken from nine stations in the rainy season. In view of the physic-chemical parameters measured on water samples, it is easy to conclude that it is of poor quality and can be of no use without prior treatment.
Laboratory results on water samples show extremely high values for Cu, Co and U 9903, respectively, 29,758 and 0,016 mg/L at the exit of effluent CHEMAF factory, station 1. The Pb and Cd were also high levels exceeding the WHO standard in all stations although they decrease with increasing distance from the CHEMAF factory. The iron in the sediment comes from the soil geochemical background and presents correlations with ETM especially in remote stations of the plant while Cu and Co have a higher content of the guidelines of the sediment quality.
The presence of high concentrations of Cu, Co, U, Cd and Pb in water and sediment at the first station (SW1) adequately demonstrates that the effluent from the metallurgical activities CHEMAF plant does not undergo treatment before to be discharged into the river Naviundu whose self-purifying capacity is limited.
Hydrometallurgical Plant Chemical of Africa (CHEMAF) is causing high concentrations of ETM found today in soils and water wells, due to its liquid effluent discharges out of its site. Indeed, two transects were established at district summers Tshamilemba to collect soil and water samples in the wells distributed along the two transects. The first has 7 GW1 point, GW2, GW3, GW4 GW 11, GW12, GW13 and the second six points GW5 GW6, GW7, GW8, GW9 and GW10. Laboratory test results indicate the presence of high concentrations of trace elements in the water with 4.112 mg/L at 13 wells, 90.551mg/L in well 1 for lead. These values exceed the WHO limit value of 2 mg/L (Cu) and 0.1mg/L (Pb). Cd presents 5.234 mg/L in 1, while the threshold value is set to 0.003 mg/L. In soil, there are also copper grades ranging from 140.8mg / kg in point 11, 945.2mg/kg in 3, these values are higher than the limit value of 100 mg/kg. Copper in high contents are encountered in the sample wells on the first transect nearby CHEMAF plant. The high contents of Cu, Pb, Cd are therefore responsible for the extinction of some plant families of different skin and respiratory diseases encountered in many people (especially young people) living in this area and especially Tshamilemba pollution Environment.