| dc.description.abstract | Heavy metal concentrations above WHO permissible limits in drinking water are a health hazard. Direct usage of water with concentrations above the set acceptable limits should therefore be avoided, stopped or the water should be treated before use. The way forward in the use of these waters is first by determining the source of these metals and how they get into the water system.
Macalder Mine area is located in Archaean .rocks, which have a potential of economic mineral occurrences like gold and copper. Mining of the ores with these economic minerals leads to excavation of various heavy metals and bringing them to the earth's surface. With the various weathering agents being active in the area, the heavy metals find their way into water system. Cadmium, chromium, copper, lead, mercury, nickel, and zinc are the heavy metals that were investigated in this study.
The investigation involved sampling of parts of Rivers Gucha and Migori and streams in the area. The analyses of the collected samples indicated very high cbncentrations of the heavy metals in some of the samples. These concentrations are above the permissible levels concentrations for safe domestic use of the water.
As discovered in one of the samples from a stream next to the mme tailings, the high
concentrations of the heavy metals-indic, ate that erosion of mine tailings plays a crucial role in
,
increasing concentrations of the heavy metals in river water. The availability of these metals in
r
water in comparison to sediments is dependent on the physico-chemical conditions operating at
the various pertions of the river floW. | en |
