Analysis Of Metal Concentrations In Surface And Groundwaters In Two Mining Communities In The Atiwa Districts Of Ghana.

Abstract

Introduction: In Ghana, mining of minerals such as gold, diamonds, bauxite and other minerals have played a significant role in the socio-economic development of the nation by reducing unemployment and generated billions of dollars for the country over the years. In recent times however, artisanal mining of gold, popularly known as galamsey has resulted in unwarranted pollution of the environment, especially rivers with mercury and other chemicals. Thus, the quality of most rivers in Ghana has been affected. Objective: The aim of the study was to determine the extent of metal pollution in ground and surface water in two mining communities in the Atiwa districts of Ghana. Methods: Water samples from groundwater (wells and bore holes), surface water (rivers) and tap water sources were analyzed for their physicochemical properties such as pH, turbidity, electrical conductivity, salinity and total dissolved solids as well as metal concentrations. Metals concentrations were measured using an Atomic Absorption Spectrophotometer whiles physicochemical parameters were measured with EDZO 7200 multimeter. Results: The mean levels of physicochemical parameters of the samples were as follows: pH: tap water-6.2+0.2, bore hole-6.8+0.26, well-7.5+0.2, river- 7.6+0.2. EC: river-76.9+15.9, tap water-104.7+54.6, bore hole-105.4+52.6, well-131.2+86.7. Salinity: river-36.9+7.3, bore hole-52.4+25.7, well-61.9+41.2, tap water-122+255. Turbidity: tap water-2.6+3.0, bore hole- 4.2+9.9, well-4.8+5.9, river-134.4+276. TDS: river-52+10.7, bore hole-73+34.8, tapwater74.8+32.0, well-86.2+57.2.The mean concentration of metals were as follows: bore hole samples: Hg-0.0002 +0.0001, As-0.004+0.002, Pb-0.009+0.005, Cd-0.013+0.018, Fe- 0.095+0.131. Well samples: Hg-0.0006+0.0005, As-0.003+0.002, Cd-0.015+0.011, Pb- 0.049+0.063, Fe-0.884+0.353. Tap water: Hg-0.0001+0.000, As-0.001+0.001, Pb-0.003+0.002, Cd-0.003+0.004, Fe-0.066+0.154 and finally the mean concentrations for river

samples were: Hg-0.0249+0.0171, Cd-0.128+0.08, Pb-0.164+0.088, As-0.233+0.938 and Fe-6.238+1.274. Conclusion: The concentrations of metals in all the tap water supplied by GWCL were within the acceptable limits set by WHO and therefore safe for consumption with regards to the metals that were analysed. The rivers that were sampled contained metal concentrations that were above WHO permissible limit for drinking water for all the metals that were analysed hence ingestion of water from these sources either directly or indirectly could pose a long term adverse health effect to the consumer.