Patterns for Arsenate and Trace Element Relationships in Surface Water and Groundwater of Obuasi Municipality of Ghana

Alexander Kwaku Banson

doi:10.11648/j.ijepp.20150305.17

Abstract

Obuasi Municipality is a historic gold mining tropical community that has a massive cocktail of old and active anthropogenic arsenic and trace metal storage structures and activities. Given the potential health impact of elevated arsenic and trace metals in surface and ground water of Obuasi Municipality, it is necessary to assess the distribution and possible link between arsenic and trace metals found in surface water and ground water of the study area. Arsenic is predominant as arsenate in the Obuasi Municipality. In response to this need, the study used statistical and geochemical analytical tools to identify patterns of relationships between arsenate distributions and trace metals in surface water and groundwater of the study area.

Highlights

IntroductionActive artisanal mining is intense, but conducted by illegal miners, since almost the entire area is covered by the concession of Anglogold Ashanti Limited, Obuasi Mine [1, 9]
Obuasi Municipality is located in the western part of the main Ashanti-Prestea gold belt mineralization and lies in the southern part of Ashanti Region of Ghana
Arsenic which is often associated with gold in the study area occurs predominantly as arsenopyrite and as a trace element in the pyrite, pyrrhotite, bournonite, tetrahedrite, sphalerite and aurostibnite [4, 9]

Summary

Introduction

Active artisanal mining is intense, but conducted by illegal miners, since almost the entire area is covered by the concession of Anglogold Ashanti Limited, Obuasi Mine [1, 9]. Arsenic which is often associated with gold in the study area occurs predominantly as arsenopyrite and as a trace element in the pyrite, pyrrhotite, bournonite, tetrahedrite, sphalerite and aurostibnite [4, 9]. Gold sulfide ores occur as disseminated assemblage of arsenopyrite, pyrite, pyrrhotite with minor chalcopyrite, stibnite, sphalerite and galena in metasediments and metavolcanics in which carbonate and sericite are the prominent alteration minerals [4,5]. The finer arsenopyrite grains are found to contain high gold concentrations occurring as sub-microscopic gold particles, and supergene concentration of gold from the sulfides extends from depth of between 30 m to 80 m [2].

Methods

Results

Conclusion