Author: Peh Kwame Peter
Department of Biochemistry
Kwame Nkrumah University of Science & Technology
Abstract
Trace metals (Fe and Hg) levels were determined in the sediments from the Weija and Kpong reservoirs between the months of December 2013 to March 2014 and the occurrences were compared. Temperature, pH, and electrical conductivity were measured as hydrographic factors. The primary objective of the study was to establish the pollution status of these reservoirs based on the levels of Fe and Hg in the sediment compared to recommended values of sediment pollution (GESAMP, 1982) and (USEPA, 1986). From the results (Table 4.3) the mean concentration of Fe (195.25±12mg/l) and Hg (0.0018±0.0056mg/l) in the Weija reservoir. The mean concentration of Fe (6.158±0.28mg/l), Hg (0.0031±0.00092mg/l) in the Kpong reservoir. The highest levels of Fe and Hg were recorded in Weija reservoir with values of (210.2 mg/l) and (0.025mg/l) respectively in the third site (Machigeni), a town close to the reservoir. It was therefore concluded that the highest levels of Fe and Hg in the Weija reservoir was an indicative of anthropogenic activities around the Weija reservoir. It is possible that the activities of Aglo Bullions Gold Miners Gh Ltd around the Weija province could introduce traces of metals into the reservoir through percolation and erosional activities. Farming activities through the use of chemical fertilizers around the Weija was also a contributing factor to the high levels of Fe and Hg in Weija than the Kpong. Despite the Weija reservoir had highest concentration of Fe than the Kpong, it is still within the recommended value (41000mg/l) of unpolluted sediments (GESAMP, 1982). The levels of Hg were also within the recommended value (<1 mg/l) of polluted sediments (USEPA, 1986). The study showed that both Fe and Hg levels were generally higher in the Weija reservoir sediments than the Kpong and therefore the Weija reservoir could be described as relatively more polluted based on the levels of the two trace metals.
Keyword: Concentration of Fe, Concentration of Hg, Elements in Bottom Sediments
