Authors: Scott, PA; Taylor, JR; Grindley, P; McLeary, M; Brett, D; Williams, DJ; O'Kane, M


DOI https://doi.org/10.36487/ACG_rep/1152_66_Scott

Cite As:
Scott, PA, Taylor, JR, Grindley, P, McLeary, M, Brett, D, Williams, DJ & O'Kane, M 2011, 'Case study for avoiding treatment in perpetuity – the Brukunga pyrite mine example', in AB Fourie, M Tibbett & A Beersing (eds), Proceedings of the Sixth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 633-643, https://doi.org/10.36487/ACG_rep/1152_66_Scott

Download citation as:   ris   bibtex   endnote   text   Zotero


Abstract:
Iron sulfide (pyrite and pyrrhotite) was mined by open pit methods at Brukunga, located 40 km east of Adelaide in the Mount Lofty Ranges of South Australia, between 1955 and 1972 to provide feedstock for sulphuric acid production in the South Australian fertiliser industry. The site has been managed by Primary Industries and Resources South Australia (PIRSA) since 1998. Eight million tonnes of waste rock (2 wt % S) were mined and stored in three waste rock dumps. 3.5 Mt of tailings (1.7 wt % S) were produced and stored in an above ground facility. The total area of disturbance at the Brukunga Mine site is 155 ha, comprising the tailings dam, waste rock storages, quarry and Brukunga township. Oxidation of the mine and processing waste, and exposed remnant sulfidic rock mass, has resulted in acid drainage (pH<3) with elevated sulfate and dissolved metals. A hydrated lime-based water treatment plant was commissioned at Brukunga in September 1980 to treat acid drainage. The plant initially treated acidic seepage from the tailings storage facility (estimated at mine closure to be 80,000 m3/year), but has subsequently been expanded to treat acidic drainage collected from the waste rock dumps and the mine workings. The plant was upgraded to a high-density sludge operation, which has improved reagent efficiency and water quality, and also reduced overall treatment costs. Dawesley Creek drains the mine site precinct and prior to June 2003 this acid drainage entered this Creek making the water unsuitable for livestock and irrigation use for up to 20 km downstream. A diversion drain was constructed in June 2003 to separate non-mine related flow in Dawesley Creek from acidic mine drainage, which is collected and treated in the water treatment plant, in an attempt to reduce the total volume of water requiring treatment. Water treatment timelines to reduce acid, metal loads are estimated to range from 300 to greater than 1000 years. PIRSA has implemented a process for determining the most effective long-term solution for the remediation of the Brukunga Mine site. The goal of the Brukunga Remediation Project is to develop a walk-away solution, which is remediation allowing return of the land to a landuse suitable for release of the land from Government ownership such that the site requires no further intervention by, ongoing responsibility for or cost to Government and/or community.

References:
ANSTO (1994) Oxidation Rates in Waste Rock Dumps and the Tailings Dam at Brukunga, Australian Nuclear Science and Technology Organisation Report, June 1994.
Blesing, N.V., Lackey, J.A. and Spry, A.H. (1975) Rehabilitation of an abandoned mine site, in Proceedings International Symposium Minerals and the Environment, M.J. Jones (ed), London, 4–7 June 1974, Institute of Mining and Metallurgy London, pp. 341–368.
Burtt, A.C. and Gum, J.C. (2000a) Soil and stream sediment sampling of the Dawesley-Bremer Catchment for potential environmental contaminants, PIRSA Report Book 2000/00002 (Department of Primary Industries and Resources South Australia).
Burtt, A.C. and Gum, J.C. (2000b) The Dawesley-Bremer Catchment: Phase 2 sampling program for potential environmental contaminants, PIRSA Report Book 2000/00019 (Department of Primary Industries and Resources South Australia).
Cox, R.C., Taylor, J., Grindley, P. and Pape, S. (2006) Successfully Lowering the Risks and Costs Associated with the Legacy of the Abandoned Brukunga Pyrite Mine, South Australia.
EGi (1995) Rehabilitation of the Brukunga minesite and tailings dam, Final report to SADME.
Gravestock, D.I. and Gatehouse, C.G. (1995) Stansbury Basin in the Geology of South Australia – The Phanerozoic, J.F. Drexel and W.V. Preiss (eds), SADME Bulletin 54, pp. 5–19.
LaGanza, R. (1959) Pyrite investigations at Nairne, SA, Economic Geology, Vol. 54, pp. 895–902.
McLeary, M.B. (2009) Striving for ‘walk-away’ — focusing an expert group on the ‘holy grail’ of mine closure, in Proceedings Fourth International Conference on Mine Closure (Mine Closure 2009), A.B. Fourie and M. Tibbett (eds), 9–11 September 2009, Perth, Australia, Australian Centre for Geomechanics, Perth, pp. 359–374.
Parsons Brinckerhoff (2005) Brukunga Mine Site: Summarising of Reports and Data Gap Analysis, Report to PIRSA (Department of Primary Industries and Resources South Australia) (unpublished).
PIRSA (2002) Department of Primary Industries and Resources South Australia. Brukunga Mine Site Environment Improvement Program, Revision 2002, A continuing program for rehabilitation of at the historic (1955–1972) Brukunga Pyrite Mine Site, Office of Minerals and Energy Resources, 40 p.
PIRSA (2003) Department of Primary Industries and Resources South Australia. Notes on the Brukunga Pyrite Mine, Primary Industries and Resources South Australia, May 2003.
Ridgeway, J. (1950) Notes on the Gibralta Pyrites Deposit, SADME report.
Scott, P.A., Taylor, J., Grindley, P. and McLeary, M. (2011) Acidity Load Contributions from Highwall Sources at the Brukunga Mine, 7th Acid Mine Drainage Workshop, Darwin, in press.
TAG (2007) Interim Report – Brukunga Remediation Project, November 2007, unpublished.
TAG (2008) Final Report on the Development and Assessment of Remediation Options for the Brukunga Remediation Project, Prepared for the Department of Primary Industries and Resources South Australia (PIRSA) by Technical Advisory Group (TAG) 31 October 2008, unpublished.
Taylor, G.F. and Cox, R.C. (2003) The Brukunga Pyrite Mine – A Field Laboratory for Acid Rock Drainage Studies, Proceedings Sixth International Conference on Acid Mine Drainage, Cairns, 12–18 July 2003, pp. 93–106.




© Copyright 2021, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
Please direct any queries or error reports to repository-acg@uwa.edu.au