The mobility, bioaccessibility and transfer pathways of metals and metalloids in estuarine sediments have been the focus of much detailed research. However, to date, few studies have examined the mineralogical siting of metals and metalloids in such sediments. This is despite the fact the mineralogy of sediments is an important factor that controls which and how much of a particular metal is released to pore waters and overlying water columns. This study reports on the mineralogical siting of metals in contaminated estuarine sediments, Hobart, Australia, and aims to evaluate the mobility of metals in the contaminated substrates. Mineralogical, mineral chemical and bulk chemical analyses demonstrate that the sediments contain very high levels of several metals and metalloids. The contaminated sediments have concentrations of zinc (Zn), lead (Pb), copper (Cu) and cadmium (Cd) ranging from 0.55 to 4.23 wt%, 0.16 to 0.70 wt%, 415 to 951 mg/kg and 23 to 300 mg/kg, respectively. Franklinite and lesser sphalerite are the main repositories of Zn, whereas much of the Pb and Cu is hosted by sulfides, organic matter and undetermined iron (Fe) oxides. While the release of contaminant loads from franklinite through dissolution is likely to be insignificant, even small releases of metals from the highly contaminated sediments can still cause the deterioration of local water quality. The contaminated sediments represent long-term sources of metal pollutants, particularly Zn, to local waters. This study demonstrates that mineralogical analyses are a vital tool to recognise the potential mobility of trace metals in estuarine environments. © 2013 Copyright Taylor and Francis Group, LLC.

Item Type:	Refereed Article
Keywords:	zinc, franklinite, sequential leach, lead, copper, metal siting, mineralogy, contamination, Derwent estuary
Research Division:	Earth Sciences
Research Group:	Geochemistry
Research Field:	Isotope geochemistry
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the earth sciences
UTAS Author:	Gregory, D (Dr Daniel Gregory)
UTAS Author:	Meffre, S (Professor Sebastien Meffre)
UTAS Author:	Large, RR (Professor Ross Large)
ID Code:	87892
Year Published:	2013
Web of Science® Times Cited:	9
Deposited By:	Centre for Ore Deposit Research - CODES CoE
Deposited On:	2013-12-14
Last Modified:	2017-11-06
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