Hydrogeochemical and Spatial Distribution of Heavy Metals in Groundwater in Auta Balefi, Northcentral, Nigeria

Water resource pollution is an issue of great concern globally. Heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), and arsenic (As) enter groundwater systems from leaching from rocks, and the activities of man like agriculture, mining, industrial activities, waste disposal, etc. This study is carried out at Auta Balefi, North-Central, Nigeria. A total of 25 water samples were collected (10 from boreholes - BH, and 15 from hand-dug wells – HDW), with the aim of determining the concentration of heavy metals in the water (by geochemical analysis) and their spatial distributiuon in the area (using remote sensing and GIS). After analysis of heavy metals concentration in groundwater, they are projected in spatial distribution maps for estimating and monitoring the quality of groundwater at study area. Analysis showed most of the heavy metals analysed were within the permissible limit in drinking water by Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organisation (WHO). Arsenic, Lead and Selenium have concentrations in some locations beyond the permissible limit in drinking water by NSDWQ and WHO, with the range of 0.002-0.578, 0.002-0.159 and 0.034-0.765mg/L, respectively. Spatial analysis showed the distribution of the heavy metals in the groundwater of Auta Balefi is of higher concentration in the north-western and south-eastern part of the area.