Field trial of ion-exchange resin columns for removal of metal contaminants, Thala Valley Tip, Casey Station, Antarctica
Introduction
Amberlite IRC748 (Rohm and Haas Ltd), an iminodiacetic acid (IDA) chelating cation-exchange resin, is being assessed for the removal of dissolved contaminant metals from the surface waters discharged from abandoned coastal waste disposal sites in cold regions. One such site is the Thala Valley Tip, an abandoned waste disposal site associated with Old Casey Station, Antarctica. Investigations have indicated that metal contamination present at the tip site is being dispersed into the marine environment of adjacent Brown Bay, largely via surface drainage, during the summer melt (Snape et al., 2002, Scouller et al., 2002, Stark et al., 2003).
Thala Valley is being developed as a case study for the investigation and remediation of coastal waste disposal sites in cold regions. During the summer melt, the temperature of surface waters is typically between 1 and 4 °C, therefore low temperature is an important site-specific factor which will affect the uptake of metals by an ion-exchange resin. Another site-specific factor is variable salinity of the surface waters. The site has been subject to periodic inundation by seawater during extreme high tides, therefore surface waters may potentially have high salinity at the point of discharge to Brown Bay.
Clean-up of the Thala Valley Tip was undertaken during the 2003–04 season at Casey Station. Water management formed an integral part of clean-up operations to limit dispersal of contaminants mobilised into meltwaters during excavation and earth-moving activities. Contaminated water was treated using a water treatment plant prior to discharge to Brown Bay. This study considers the operation of the ion-exchange columns of Amberlite IRC748 for removal of dissolved metals during clean-up activities as a field trial.
Our previous laboratory batch equilibrium studies (Woodberry et al., 2006) have indicated that dissolved metal contaminants can be successfully removed by Amberlite IRC748 in the presence of the main seawater matrix ions (Na, Ca and Mg) at 4 and 20 °C, and that increased salinity actually lowers the selectivity of the resin for Ca and Mg. Our previous laboratory dynamic flow studies (Woodberry et al., 2006) have also indicated that dissolved metal contaminants can be successfully removed by Amberlite IRC748 under variable salinity and low temperature conditions, and that the order of selectivity for the contaminant metal ions under field conditions (10% seawater and 4 °C) would be expected to be: Cu > Pb > Ni > Zn > Cd.
As part of this field trial, an on-site monitoring technique for measuring dissolved metal contaminants was also investigated. On-site monitoring of water quality during contaminated site remediation is an integral component of most remediation plans. This involves careful measurement of chemical parameters at very low concentrations, often using expensive techniques such as ICP–MS. Hence preconcentration techniques which are simple and reproducible can be very useful in situations where results are required quickly and laboratory infrastructure may be limited.
Section snippets
Ion-exchange columns
The water treatment plant (WTP) was used to treat contaminated meltwaters retained in the tip site during excavation activities and drained from waste containers (excavated materials contained large quantities of ice and snow which melted during the summer). A multistage treatment process was employed for the removal of particulate material and dissolved metal contaminants, contained within a modified sea-container for ease of mobility and deployment (Northcott et al., 2007). The layout of the
Concentrations of metals
The main dissolved metal contaminants identified to be present in meltwaters treated by the ion-exchange columns were Cd, Cu, Pb, Ni and Zn, with some colloidal iron present. Their concentrations in the inlet water to the columns can be separated into three distinct periods of water treatment during clean-up operations in Thala Valley (Fig. 4a–f). The first period (0 to 50 kL treated) was at the beginning of the summer when small volumes of meltwater were percolating through contaminated
Column outlet concentrations
Dissolved contaminant metal concentrations of the inlet and outlet water of the ion-exchange columns during operation over the 2003–04 season are presented in Fig. 4a to f.
The ion-exchange columns substantially reduced the concentrations of dissolved metal contaminants in contaminated meltwaters, despite the low temperature and salinity levels, confirming the results of previous laboratory studies. The high concentrations of metals in the meltwaters from the waste containers (from 150 kL to
Detection limits and reproducibility
Dissolved metal concentrations in outlet water from the ion-exchange columns were in the very low μg L− 1 range, and therefore likely to be approaching the detection limit of the on-site monitoring technique. The calibration error of the AAS was estimated for its contribution to the overall error. The method blanks generally exceeded instrument detection limits and variability, and thus dictated the overall method detection limit, as summarised in Table 4. It is noted that the analytical data
Discussion
The breakthrough data for the ion-exchange columns was used as an indication of the selectivity of the resin for the different contaminant metals; less breakthrough indicating higher selectivity. The order of selectivity observed for the field trial was:Cd ∼ Zn > Ni ∼ Cu > Fewhich is markedly different to the order of selectivity observed in the laboratory column breakthrough tests (Woodberry et al., 2006). The order of selectivity observed for the contaminant metals at 4 °C for the non-buffered
Conclusions
The field trial indicated that prior to breakthrough, the concentrations of contaminant metals in meltwaters discharged from the Thala Valley Tip during clean-up operations were successfully reduced by ion-exchange columns of Amberlite IRC748, despite the low temperature and variable salinity levels. The overall order of selectivity exhibited by the resin in the field trials was: Cd ∼ Zn > Ni ∼ Cu > Fe. This order of selectivity was unexpected based on observations of laboratory column breakthrough
Acknowledgements
The authors would like to acknowledge funding from Australian Antarctic Science Grant 1300 and the support of the Particulate Fluids Processing Centre, a Special Research centre of the ARC at the University of Melbourne. The authors would also like to thank Dr Ash Townsend for ICP–MS analysis at the CSL, University of Tasmania and Mr Nick Graham for AAS analysis at Casey Station.
References (18)
- et al.
Performance of different preconcentration columns used in sequential injection analysis and inductively coupled plasma-mass spectrometry for multielemental determination seawater
Spectrochimica Acta Part B: Atomic Spectrometry
(2002) - et al.
Study of trace metal partitioning between soil–EDTA extracts and Chelex-100 resin
Analytica Chimica Acta
(2006) - et al.
Trace metals analysis in estuarine and seawater by ICP–MS using on line preconcentration and matrix elimination with chelating resin
Talanta
(1999) - et al.
Water treatment design for site remediation at Casey Station, Antarctica: site characterisation and particle separation
Cold Regions Science and Technology
(2003) - et al.
Water treatment to prevent contaminant dispersal during remediation of cold regions contaminated sites
Cold Regions Science and Technology
(2007) - et al.
Human impacts in Antarctic marine soft-sediment assemblages: correlations between multivariate biological patterns and environmental variables
Estuarine, Coastal and Shelf Science
(2003) - et al.
An improved method for rapid preconcentration and determination of bioactive trace metals in seawater using solid phase extraction and high resolution inductively coupled plasma mass spectrometry
Marine Chemistry
(1998) - et al.
Flame atomic absorption spectrometric determination of chromium(VI) by on-line preconcentration system using a PTFE packed column
Talanta
(2001) - et al.
Users' Manual for WATEQ4F, with Revised Thermodynamic Data Base and Test Cases for Calculating Speciation of Major Trace and Redox Elements in Natural Waters
(1991)
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