Prediction of minesite-drainage chemistry through closure using operational monitoring data

Reprocessing and environmental desulphurization of sulphide mining waste from sphalerite flotation: case of Chaabet El Hamra mine, Algeria

“…Mining effluents are fed by mine drainage, which can be divided into four main mining drainage classes (Morin and Hutt, 1997), namely, acid mine drainage (pH < 6) which is the case for Chaabet El Hamra, alkaline mine drainage (pH > 9-10), neutral mine drainage (6 < pH < 9-10) and mine drainage at low pH. The type of drainage which is a source of environmental concern in Algeria is AMD which contains elements in solution at significant concentrations.…”

Analytical Framework for a Risk-based Estimation of Climate Change Effects on Mine Site Runoff Water Quality

“…The large number of closed and/or abandoned mine sites worldwide also requires reliable water quality estimates to assess carrying costs for industry and governments (Puura and D'Alessandro 2005;Bowell 2004, 2005a, b) From a more fundamental science perspective, the long-term predictions for mine site water quality challenge our understanding of various climate, hydrology, and geochemical models and their underlying biogeochemical and physical basis (Gammons et al 2006;Morin and Hutt 1997). In order to estimate mine waste water quality into the future, the typical approach within the regulatory, industrial, and academic communities is to develop advanced probabilistic and/or deterministic water balances for a relatively stationary post-closure site layout and topography that is coupled to steady state geochemical weathering predictions under a variety of risk scenarios (Morin and Hutt 1997). Although some of these water quality models for mine site wastes incorporate forward-looking water balances based on estimated precipitation patterns over the coming century, there is a general neglect of potential climate change impacts on both water balances and geochemical weathering rates.…”

“…To estimate short-through long-term weathering rates of mine wastes, samples of the material are generally subjected to static and kinetic laboratory test work such as acid-base accounting, humidity cells, and leach columns (Frostad et al 2002;Morin and Hutt 1997;Paktunc 1999). The standard laboratory test work commonly only characterizes chemical weathering reactions.…”

“…Because of this, some have noted there is often a large discrepancy in mineral weathering rates between laboratory and field scales (Schnoor 1990). However, the wide prevalence of laboratory test work within well-established regulatory and research frameworks, and the lack of adequate fieldwork programs to provide the correlative linkages between laboratory and field weathering rates, means that mass normalized laboratory weathering rates are typically extrapolated directly to field conditions, perhaps with an additional surface normalization factor (Morin and Hutt 2001). For tailings, such surface area normalization factors may not be necessary, since laboratory test work is performed on material having a particle size distribution close to that expected in the field.…”

“…For tailings, such surface area normalization factors may not be necessary, since laboratory test work is performed on material having a particle size distribution close to that expected in the field. By comparison, waste rock dump median particle sizes (d 50 values) can often be on the order of tens of centimeters (and with less uniformly distributed particle sizes), significantly larger than the typical sub-cm d 50 values obtained after material is crushed into a relatively uniform distribution for laboratory test work (Morin and Hutt 1997;Stromberg and Banwart 1999). Such differences necessitate surface area normalization factors to avoid gross overestimates of field weathering rates.…”