Authors: McCullough, CD; Müller, M; Eulitz, K; Lund, MA


DOI https://doi.org/10.36487/ACG_rep/1152_61B_McCullough

Cite As:
McCullough, CD, Müller, M, Eulitz, K & Lund, MA 2011, 'Modelling a pit lake district to plan for abstraction regime changes', in AB Fourie, M Tibbett & A Beersing (eds), Proceedings of the Sixth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 581-591, https://doi.org/10.36487/ACG_rep/1152_61B_McCullough

Download citation as:   ris   bibtex   endnote   text   Zotero


Abstract:
Mining pit lakes can form in open cut mining pits that extend below the groundwater table. Final lake surface levels generally represent the greatest risk of pit lake closure to stakeholders through potential to overflow and discharge to regional surface water bodies and groundwater resources. An essential prerequisite for managing this risk is a good understanding of the lake’s water budget. Pit lakes in the Collie Coal Basin ,Western Australia form a lake district currently consisting of 13 lakes exceeding a total volume of 200 GL of acid and metalliferous (AMD) degraded water. Given long-term risks for off-site contamination, regulatory agencies often rely on geochemical predictions of future pit lake water quality to evaluate closure strategies that protect the surrounding environment. Using an existing regional groundwater model, we modelled representative pit lake types in the Collie Lake District, south-western Australia, to determine different regional groundwater abstraction regime effects on pit lake water levels. PITLAKQ was used to model three different lakes representing three distinct lake types identified by conceptual modelling: Historic (around 50 years old), New/Rehabilitated, and New/ Unrehabilitated (both around 5–15 years old). An accurate representation of the water level-volume relationships was developed before all available data on major hydrological sinks and sources such as groundwater inflow/outflow, surface water inflow/outflow, as well as precipitation and evaporation were considered in lake water budget calculations. Although we found large deviations between measured and calculated water levels we could show reasonable limits for groundwater inflows and outflows by examining different scenarios. Reciprocally, this improved the groundwater model(s) suggesting coupling fine-scale pit lake models with groundwater models to identify the data quality for sinks and sources as an approach for other pit lake models. Our modelling scenarios showed that planned groundwater abstraction regime changes would lead to only limited changes in lake water depth compared to modelling uncertainties resulting from limited available data and the use of a regional groundwater model. This example illustrates pit lake modelling with low data availability still allows useful scenario testing under different operational scenarios.

References:
Bell, L.C. (2001) Establishment of native ecosystems after mining – Australian experience across diverse biogeographic zones, Ecological Engineering, Vol. 17, pp. 179–186.
Castendyk, D.N. and Webster-Brown, J.G. (2007) Sensitivity analyses in pit lake prediction, Martha Mine, New Zealand 1: Relationship between turnover and input water density, Chemical Geology, Vol. 244(1–2), pp. 42–55.
Cole, T.M. and Buchak, E.M. (1995), CE-QUAL-W2: A two-dimensional, laterally averaged, hydrodynamic and water quality model, 2.0, US Army Corps of Engineers, Waterways Experiment Station, USA.
Craven, E. (2003) Acid Production in the Overburden of Lake WO5B, Collie. Environmental Engineering Project 640.406, thesis, Centre for Water Research, University of Western Australia, Australia, Perth, November 2003.
Doupé, R.G. and Lymbery, A.J. (2005) Environmental risks associated with beneficial end uses of mine lakes in southwestern Australia, Mine Water and the Environment, Vol. 24(3), pp. 134–138.
Eary, L.E. (1999) Geochemical and equilibrium trends in mine pit lakes, Applied Geochemistry, Vol. 14(8),
pp. 963–987.
Farrell, T. (1998) Major decommissioning issues for the Australian mining industry, Proceedings of the Workshop on Environmental Issues in the Decommissioning of Mine Sites, Australian Centre for Mining Environmental Research (ACMER), Kenmore, Australia, pp. 11–15.
Hamblin, P.F., Stevens, C.L. and Lawrence, G.A. (1999) Simulation of Vertical Transport in Mining Pit Lake, Journal of Hydraulic Engineering, Vol. 125(10), pp. 1029–1038.
Huber, A., Ivey, G.N., Wake, G. and Oldham, C.E. (2008) Near-surface wind-induced mixing in a mine lake, Journal of Hydraulic Engineering, Vol. 134(10), pp. 1464–1472.
Jin, Q. and Bethke, C.M. (2005) Predicting the rate of microbial respiration in geochemical environments, Geochimica et Cosmochimica Acta, Vol. 69(5), pp. 1133–1143.
Johnson, S.L. and Wright, A.H. (2003) Mine void water resource issues in Western Australia, Hydrogeological Record Series, Report HG 9, by Water and Rivers Commission, Perth, Australia, 93 p.
Kalin, M., Cao, Y., Smith, M. and Olaveson, M.M. (2001) Development of the phytoplankton community in a pit-lake in relation to water quality changes, Water Research, Vol. 35(13), pp. 3215–3225.
Kumar, R.N., McCullough, C.D. and Lund, M.A. (2009) Water resources in Australian mine pit lakes, Mining Technology, Vol. 118(3/4), pp. 205–211.
Lund, M.A. and McCullough, C.D. (2008) Limnology and ecology of low sulphate, poorly-buffered, acidic coal pit lakes in Collie, Western Australia, Proceedings of the 10th International Mine Water Association (IMWA) Congress, Karlovy Vary, Czech Republic, N. Rapantova, Z. Hrkal (eds), pp. 591–594.
McCullough, C.D. and Lund, M.A. (2006) Opportunities for sustainable mining pit lakes in Australia, Mine Water and the Environment, Vol. 25(4), pp. 220–226.
McCullough, C.D. and Lund, M.A. (2010) Mine Voids Management Strategy (IV): Conceptual Models of Collie Basin Pit Lakes, Department of Water Project Report by MiWER/Centre for Ecosystem Management Report 2010–12, Edith Cowan University, Perth, Australia. Unpublished report to Department of Water.
McCullough, C.D., Hunt, D. and Evans, L.H. (2009) Sustainable development of open pit mines: creating beneficial end uses for pit lakes, Mine Pit Lakes: Characteristics, Predictive Modeling, and Sustainability, D. Castendyk, T. Eary, B. Park (eds), Society for Mining Engineering (SME), Kentucky, USA, pp. 249–268,
Miller, G.E., Lyons, W.B. and Davis, A. (1996) Understanding the water quality of pit lakes, Environmental Science and Technology, Vol. 30(3), pp. 118A–123A.
Müller, M. (2004) Modellierung von Stofftransport und Reaktionen mit einem neuent¬wickelten, gekoppelten Grund- und Oberflächenwassermodell am Beispiel eines Tagebaurestsees, thesis, Dresden.
Müller, M. (2011) The PITMOD website, viewed 1 May 2011, .
Müller, M. and Werner, F. (2004) Groundwater-Lake-Interactions at Lake Bärwalde and its Implications on Predictions of Lake Water Quality, Proceedings of International Conference on Finite Element Models, MODFLOW, and More: Solving Groundwater Problems, K. Kovar, Z. Hrkal & J. Bruthans (eds), 13–16 September 2004, Karlovy Vary, Czech Republic, pp. 249–252.
Niccoli, W.L. (2009) Predicting Groundwater Inputs to Pit lakes (Chapter 8), Mine pi lakes: characteristics, predictive modeling, and sustainability, D.N. Castendyk and L.E. Eary (eds) Society for Mining, Metallurgy & Exploration (SME), Littleton, Colorado, USA, pp. 91–99.
Parkhurst, D.L. and Appelo, C.A.J. (1999) User’s guide to PHREEQC (Version 2) - A computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations, Water-Resources Investigations Report 99-4259, by U.S. Geological Survey, 310 p.
Salmon, S.U., Oldham, C. and Ivey, G.N. (2008) Assessing internal and external controls on lake water quality: limitations on organic carbon-driven alkalinity generation in acidic pit lakes, Water Resources Research 44(W10414).
Sappal, K., Zhu, Z.R., Rathur, Q. and Hodgkin, T. (2000) Subsurface geology, hydrogeological and geochemical analysis of the Ewington Open Cut No 2 lake area, Collie Basin, Final void water quality enhancement: Stage III, ACARP Project Number C8031 report, Perth, pp. 11–68.
Varma, S. (2002) Hydrogeology and groundwater resources of the Collie Basin, Western Australia, Hydrogeological Record Series HG 5, by Water and Rivers Commission, Perth. 80 p.
Waterhouse, J.A. and Davidge, S. (1999) The evolution of the water body in the final void of the Mount Goldsworthy Mine, Proceedings Water 99 Joint Congress, 6–8 July 1999, Brisbane, Australia, pp. 895–900.
Werner, F., Eulitz, K., Graupner, B. and Müller, M. (2008) Pit Lake Bärwalde Revisited: Comparing Predictions to Reality, Proceedings of the 10th International Mine Water Association (IMWA) Congress, Karlovy Vary, Czech Republic, 4 p.
Zhang, Q., Varma, S., Bradley, J. and Schaeffer, J. (2007) Groundwater model of the Collie Basin, Western Australia, Hydrogeological Record Series, Report HG 15, Water and Rivers Commission, Perth, Australia, 106 p.




© Copyright 2020, 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