TRACE METALS ANALYSIS OF SOIL AND WATER SAMPLES FROM A LIMESTONE-MINING SITE IN SOKOTO STATE NIGERIA.

^aItumoh, Emeka J.^*; ^bIzuagie, Thompson.; ^aOmaka, Ndukaku O.; ^cUba, Ahmad.; ^bShuaibu, Malami.; ^bDogonyaro, Ismaila. A.; ^bIsah, Abdullahi.; ^bDange, Attahiru. U. and ^bIsah, Saidu I.

^aDepartment of Industrial Chemistry, Ebonyi State University, Abakaliki
^bDepartment of Natural Sciences, Sokoto State Polytechnic, Sokoto
^cDepartment of Pure and Applied Chemistry, Usmanu Danfodiyo University, Sokoto

^*E-mail: ray.chukwuemekajude@yahoo.com

ABSTRACT
Atomic absorption spectrophotometeric determination of metal contents of soil and water samples of a limestone-mining site is presented in this report. The work is based on the concern that the concentration of metals in soils, ground and surface water increases as a result of mining and other industrial activities. Soil and water samples collected from the site in Kalambaina were analyzed for metals (Fe, Mn, Zn, Ni, Pb, and Cu) by AAS model 210 VGP after pre-sample treatments. The results yielded 1.57 ± 0.4 mgL^-1 and 0.29 ± 0.02 mgL^-1 Zn for soil and water samples respectively. Pb (0.03 ± 0.007) mgL^-1, Mn (0.16 ± 0.02) mgL^-1 were detected in the soil sample only, while Ni, Cu and Fe were not detected in both the soil and water samples. Temperature, pH, electrical conductivities, turbidity, total alkalinity and hardness of the soil and water samples were analyzed to help in the study of the work. The result suggests that the metal concentrations of the site might have resulted from atmospheric depositions, traffic activities, bedrock geochemistry and mining activities. The metal concentrations of the studied site were all below the maximum permissible limits and thus posses no contamination threat to water flowing from it.

Keywords: Limestones, mining, trace metals, Kalambaina, Sokoto