Column tests to assess water flow and oxygen transport in a monolayer cover placed on acid generating tailings

Authors: Pabst, T; Aubertin, M; Bussière, B; Molson, J

DOI https://doi.org/10.36487/ACG_rep/1152_34_Pabst

Cite As:
Pabst, T, Aubertin, M, Bussière, B & Molson, J 2011, 'Column tests to assess water flow and oxygen transport in a monolayer cover placed on acid generating tailings', in AB Fourie, M Tibbett & A Beersing (eds), Mine Closure 2011: Proceedings of the Sixth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 313-322, https://doi.org/10.36487/ACG_rep/1152_34_Pabst

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Abstract:
This study focuses on the reclamation work being performed on an old acid generating tailings site, located in Quebec, Canada. The tailings are partially oxidised due to extended exposure, so the pore water is already acidic. A monolayer cover, made of non acid-generating tailings, is being considered to control acid mine drainage. The goal of the investigation is to assess the behaviour of the tailings-cover system under various conditions, and also, if needed, evaluate alternative reclamation options. To do so, tailings samples were collected in situ and characterised in the laboratory. Large columns have been set up to evaluate the hydrogeological and geochemical response of the tailings and cover following wetting cycles. The instrumented columns were designed to reproduce some of the existing site conditions and provide representative results for long term analyses. Monthly wetting and drying cycles were repeated to simulate climatic conditions. The water content, suction, and oxygen concentration were monitored over time. Experimental data are used to calibrate and to help validate numerical models constructed with Vadose/W (GeoSlope Inc.). Additional simulations are conducted to evaluate the effect of various influence factors, such as depth of the water table and material properties. Alternative cover configurations are also tested. The results presented in this paper focus on unsaturated water flow in the tailings-covers system, and on the diffusive oxygen flux.

References:
Aachib, M. (1997) Etude en laboratoire de la performance des barrières de recouvrement constituées de rejets miniers pour limiter le DMA. PhD Thesis, Mineral Engineering, Ecole Polytechnique de Montréal, 298 p.
Aachib, M., Aubertin, M. and Chapuis, R.P. (1994) Column tests investigation of milling wastes properties used to build cover systems. Proc. Int. Land Reclamation and Mine Drainage Conf., Pittsburgh, Vol. 2, pp. 128–137.
Aachib, M., Mbonimpa, M. and Aubertin, M. (2004) Measurement and prediction of the oxygen diffusion coefficient in unsaturated media, with applications to soil covers. Water, Air and Soil Pollution 156, pp. 163–193.
Adu-Wusu, C. and Yanful, E.K. (2007) Post-closure investigation of engineered test covers on acid-generating waste rock at Whistle Mine, Ontario. Can. Geotech. J., 44(4), pp. 496–506.
Aubertin, M., Bussière, B. and Bernier, L. (2002) Environnement et gestion des rejets miniers. Manual on CD-ROM, Presses Internationales Polytechnique, Montreal, Canada.
Aubertin, M., Bussière, B., Monzon, M., Joanes, A.M., Gagnon, D. Barbera, J.M., Aachib, M., Bédard, C., Chapuis, R.P. and Bernier, L. (1999) Etude sur les barrières sèches construites à partir des résidus miniers. Phase II : Essais en place. Rapport de Recherche, Projet CDT P1899. NEDEM/MEND 2.22.2c.
Aubertin, M., Chapuis, R.P., Aachib, M., Ricard, J.F., Tremblay, L., and Bussière, B. (1994) Cover technology for acidic tailings: Hydrogeological properties of milling wastes used as capillary barrier. Proceedings 1st International Congress on Environmental Geotechnics, Edmonton, pp. 427–432.
Aubertin, M., Mbonimpa, M., Bussière, B., and Chapuis, R.P. (2003) A model to predict the unsaturated hydraulic conductivity from basic geotechnical properties. Can. Geotech. J., 40(6), pp. 1104–1122.
Aubertin, M., Molson, J., Bussière, B. and Dagenais, A.M. (2006) Investigations of layered cover systems acting as oxygen barriers to limit acid mine drainage. Proceedings 5th ICEG Environmental Geotechnics: Opportunities, Challenges and Responsibilities for Environmental Geotechnics, Thomas H.R. (ed.), 26–30 June 2006, Cardiff UK. Thomas Telford, Vol. 2, pp. 827–835.
Bussière, B., Benzaazoua, M., Aubertin, M. and Mbonimpa, M. (2004) A laboratory study of covers made of low-sulphide tailings to prevent acid mine drainage. Environmental Geology, 45(5), pp. 609–622.
Bussière, B., Maqsoud, A., Aubertin, M., Martschuk, J., McMullen, J. and Julien, M. (2003) Results from the monitoring program at the LTA site: hydraulic behavior of the cover. In Proceedings of the ICM Conference, May 4–7, 2003, Montréal, Qc.
Bussière, B., Maqsoud, A., Aubertin, M., Martschuk, J., McMullen, J. and Julien, M. (2006) Performance of the oxygen limiting cover at the LTA site, Malartic, Quebec.CIM Bulletin 1(6), pp. 1–11.
Bussière, B., Maqsoud, A., Demers, I., Aubertin, M. and Chapuis, R.P. (2011) Modélisation physique de divers scénarios de recouvrement et étude du comportement hydrogéologique: Site Manitou, Rapport Final présenté au MRNF, 144 p. (in preparation).
Chapuis, R.P. and Aubertin, M. (2003) On the use of the Kozeny-Carman equation to predict the hydraulic conductivity of soils. Canadian Geotechnical Journal, 40(3), pp. 616–628.
Cissokho, F. (2007) Études numériques des effets de la configuration des couvertures à effets de barrières capillaires inclinées sur la diffusion de l’oxygène. M.Sc.A. Thesis, École Polytechnique de Montréal-UQAT.
Collin, M. and Rasmuson, A. (1988) A comparison of gas diffusivity models for unsaturated porous media. Soil Sci. Soc. Am. J., 52, pp. 1559–1565.
Demers, I., Bussière, B., Mbonimpa, M. and Benzaazoua, M. (2009) Oxygen diffusion and consumption in low sulphide tailings covers. Can. Geotech. J., 46, pp. 454–469.
Gosselin, M. (2007) Etude de l'influence des caractéristiques hydrogéochimiques des résidus miniers réactifs sur la diffusion et la consommation de l'oxygène. M.Sc.A. Thesis, Mineral Engineering, Ecole Polytechnique de Montréal, 216 p.
Jambor, J.L. (1994) Mineralogy of sulfide-rich tailings and their oxidation products. In Short Course Handbook on Environmental Geochemistry of Sulfide Mine-Wastes. Edited by D.W. Blowes and J.L. Jambor, Mineralogical Association of Canada.
Mbonimpa, M., Aubertin, M., Aachib, M. and Bussière, B. (2003) Diffusion and consumption of oxygen in unsaturated cover materials. Can. Geotech. J., 40(5), pp. 916–932.
Mbonimpa, M., Aubertin, M., Chapuis, R.P. and Bussière, B. (2002) Practical pedotransfer functions for estimating the saturated hydraulic conductivity. Geotech. and Geol. Eng., 20(3), pp. 235–259.
Mualem, Y. (1976) A new model for predicting the hydraulic conductivity of unsaturated porous media. Water Resources Research, 12, pp. 513–522.
Nicholson, R.V., Gillham, R.W., Cherry, J.A. and Reardon, E.J. (1989) Reduction of acid generation in mine tailings through the use of moisture-retaining layers as oxygen barriers. Can. Geotech. J., 26, pp. 1–8.
Orava, D.A. and Swinder, R.C. (1996). Inhibiting acid mine drainage throughout the mine life cycle. CIM Bulletin, 98(999), pp. 52–56.
Ouangrawa, M. (2007) Etude expérimentale et analyse numérique des facteurs qui influencent le comportement hydro-géochimique de résidus miniers sulfureux partiellement submergés. Ph.D. Thesis, Mineral Engineering, Ecole Polytechnique de Montréal. 428 p.
Ouangrawa, M., Aubertin, M., Molson, J., Bussière, B. and Zagury, G.J. (2010) Preventing acid mine drainage with an elevated water table: Long-term column experiments and parameter analysis. Water, Air and Soil Pollution, 213, pp. 437–458.
Ouangrawa, M., Molson, J., Aubertin, M., Bussière, B. and Zagury, G.J. (2009) Reactive transport modelling of mine tailings columns with capillarity-induced high water saturation for preventing sulfide oxidation. Applied Geochemistry, 24, pp. 1312–1323.
Pabst, T. (2011) Analyse de divers recouvrements pour la restauration d’anciens parcs à résidus miniers générateurs d’acide. PhD Thesis, Mineral Engineering, Ecole Polytechnique de Montréal (in preparation).
Pabst, T., Molson, J., Aubertin, M. and Bussière, B. (2011) Physical and geochemical transport modelling of pre-oxidised acid-generating tailings with a monolayer cover, in Proceedings Sixth International Conference on Mine Closure (Mine Closure 2011), A.B. Fourie, M. Tibbett and A. Beersing (eds), 19–21 September 2011, Lake Louise, Canada, Australian Centre for Geomechanics, Perth, pp. 323–332.
Shakelford, C.D. and Benson, C.H. (2006) Selected factors affecting water-balance predictions for alternative covers using unsaturated flow models. GeoCongress 2006: Geotechnical Engineering in the Information Technology Age.
van Genuchten, M.Th. (1980) A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J., 44, pp. 892–898.
Wilson, G.W., Albright, W.H., Gee, G.W., Fayer, M.J. and Ogan, B.D. (1999) Alternative cover assessment project : Phase 1 report final technical report. US Environmental Protection Agency, Washington, USA, 202 p.
Yanful, E.K. and Catalan, L.J.J. (2002) Predicted and field-measured resuspension of flooded mine tailings. ASCE Journal of Environmental Engineering, 128: pp. 341–351.




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