Trace metal enrichment observed in soils around a coal fired power plant in South Africa

Amaris Dalton,Kaylin Barber,Gregor T Feig

doi:10.17159/2410-972x/2018/v28n2a1

Abstract

A site assessment was conducted at a coal fired power plant in South Africa to determine whether surrounding soils were being enriched with trace metals resulting from activities at the power plant. It was found that deposition of fly ash from the flue stacks and the ash dump along with deposition of coal dust from the coal stock yard were the activities most likely to lead to such enrichment. Eighty topsoil samples were gathered and analysed for total metal content. Results were interpreted within the context of background values. It was found that concentrations of As, Cu, Mn, Ni and Pb exceeded local screening levels, but only As and Pb could be confidently attributed to anthropogenic intervention and actual enrichment.

Highlights

Coal fired thermal power plants are one of the largest anthropogenic sources of trace metals in the natural environment (Dragovic et al, 2013)
Numerous exceedances of the conservative SSV1 were observed for As, Cu, Mn, Ni, Pb – which was considered the first indicator of anthropogenic enrichment for these metals
An integrated and holistic approach to a site assessment for contaminated land was taken at a coal fired power plant in the Mpumalanga province of South Africa

Summary

Introduction

Coal fired thermal power plants are one of the largest anthropogenic sources of trace metals in the natural environment (Dragovic et al, 2013). The nature and extent of possible enrichment of trace metals in soils that might arise from the various operations at such a power plant were investigated through an in-situ site assessment. A holistic view of soil pollution at a coal fired power plant can be formed. Due to national and international similarities in the designs of coal fired power plants, it is expected that the contamination profiles and patterns observed within this study, would to some extent be mirrored at other sites depending, on the composition of coal burnt and emission controls in place.

Methods

Results

Conclusion