ANALYSES OF SOME SELECTED HEAVY METALS AND CONTAMINANTS IN UNDERGROUND WATER AND THREE SATELLITE RIVER STATIONS IN OWERRI LOCAL GOVERNMENT AREA OF IMO STATE.
ABSTRACT
Water samples from ground water and some rivers from Owerri Local Government Area of Imo state Nigeria, were investigated for contaminants and heavy metals. The results obtained showed that in the month of April 2009, the ground water had mean maximum concentration 1.303 mg/dm3 of Pb, 1.048mgldm3 of Pb,1.488mgldm3 of Pb,for Otamiri and Oramiriukwa rivers respectively.For the month of May 2009, the ground water results showed maximum mean concentration 1.016mg/dm3 of Pb,1.069mg/dm3 of Pb, 1.7mg/dm3of Pb and 1.488mg/dm3 of Pb,for Otamiri and Oramiriukwa rivers respectively.The underground waters had mean concentration of 3.636mg/dm3 Cu,which exceeded WHO standard of 3.0mg/dm3 for drinking water.In the month of may Oramiriukwa river had Mn with a maximum mean concentration of 3.334mg/dm3 which exceeded the WHO standard of 2.0mg/dm3. The results showed lead of values 2.852mg/dm3 for the ground waters, 0.255mg/dm3 of lead , 1.045mg/dm3 of Lead and 0.855mg/dm3 of Lead for Otamiri,Nworie and Oramiriukwa rivers respectively. The correlation coefficient matrix for the element of 0.500 was taken to be significant. For the ground waters, Fe2+, Zn2+ were strongly correlated during April/June 2009 periods. The Otamiri river results showed that the heavy element Cu2+, Fe2+, Mn2+ and Zn2+ were strongly correlated in the month of April/May 2009 . The samples from Nworie River had strong correlation for the element Fe2+ Mn2+ and Zn2+ for the period of April/May 2009.Cu2+had strong correlation in the period April/May 2009. Oramiriukwa River had strong correlation for elements Cu2+, Fe2+, Pb2+ and Zn2+ in the period April/May 2009. Pb+ had strong significance in the April/May 2009 period. Mn24+ had very strong correlation in April/May 2009. A histogram chart of the frequency distribution of the heavy metal concentrations in the period,the pollution index of the water bodies were determined using Horton’s rule. The above results indicate that some of these water bodies should not be taken orally without treatment. Nworie river was founded most polluted of all the water bodies, followed by Oramiriukwa river, Otamiri river had mild pollutions, one of the ground water site’s was reported as heavily polluted with the element copper with a concentration of 3.636mg/dm3. It was discovered that none of the water sources investigated met WHO standards for safe water.