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Managing environmental performance of waste dump facilities in mining complexes is an integral part of long-term production planning. Sustainable long-term production scheduling solutions are desired to mitigate risk and return the environment to a productive post-mining state. A simultaneous stochastic optimisation framework for long-term production scheduling in mining complexes is developed that integrates waste management and progressive reclamation. The waste dump placement schedule is jointly optimised with the extraction sequence, destination policy, and stockpiling decisions in a single stochastic mathematical programming framework. This includes the timing of progressive reclamation activities in parallel with production to enhance waste dump rehabilitation. Uncertainty related to the production of acid rock drainage is quantified by simulating geochemical properties of waste and managing the blending of uncertain waste properties within the optimisation framework. With respect to the framework for simultaneous stochastic optimisation, contextual bandits are explored to improve the metaheuristic solution approach and solve the corresponding large-scale optimisation model. The framework is tested in a multi-mine copper-gold mining complex leading to improved environmental performance. Risk of acid rock drainage is decreased by 52.5% in the waste dump facilities. Reclamation planning activities for meeting environmental requirements are scheduled prior to closure. The solution approach more effectively improves the objective function with contextual bandits leading to a 24% improvement in the study presented. [ABSTRACT FROM AUTHOR]

Energy companies in the Athabasca Oil Sands Region in Alberta, Canada are evaluating the viability of incorporating pit lakes into reclamation closure designs to both sequester tailings and re-integrate the mining lease into the broader natural landscape. Lake Miwasin is a pilot-scale oil sands pit lake encompassed by a constructed catchment where the volume of the water cap is not actively managed. This study compared the water balance during the open water season over two consecutive years with contrasting levels of summertime precipitation. The first year had above average rainfall triggering surface water inflow events that diluted the over-winter water volume by ~ 25%. Flushing of the deepest layers of the water column was restricted from May – September as thermal stratification inhibited complete lake mixing. The second year had below average rainfall resulting in minimal surface water inflow and a drop in lake stage of ~ 30 cm. As the constructed catchment lacks both natural water bodies and connectivity to a legacy groundwater system, freshwater additions to the lake during the summer season were governed by rainfall. This research highlights challenges with constructing sustainable reclamation landscapes within a region characterised by variations in interannual and decadal water cycles. [ABSTRACT FROM AUTHOR]

This paper proposes a method to probabilistically quantify the moments (mean and variance) of excavated material during excavation by aggregating the prior moments of the grade blocks around the given bucket dig location. By modelling the moments as random probability density functions (pdf) at sampled locations, a formulation of the sums of Gaussian-based uncertainty estimation is presented that jointly estimates the location pdfs, as well as the prior values for uncertainty coming from ore body knowledge (obk) sub-block models. The method was tested in a region situated in the Brockman Iron Formation of the Hamersley Province, Western Australia. [ABSTRACT FROM AUTHOR]

In finding what physiological characteristics can be used to predict ground cover success on mine reclamation sites, 14 herb and grass species were tested. Establishment and early growth was tested on three different soils, ie vermiculate and quartz sand mixture, quarry overburden and coal mine overburden in a greenhouse. The results indicate that plant height and cover, transpiration rate and foliar pigments may be used to select plant adaptability to mined soil. White clover (Trifolium repens L.) showed the greatest potential as ground cover for mined soils. Species most widely used in reclamation tended to be perennials of moderate rate. [ABSTRACT FROM AUTHOR]

This publication presents the research results concerning determination of the level of landscape attractiveness of the abandoned quarries. The research focused upon 20 structures located within the area of Poland, Great Britain and Austria. The research used procedures of landscape attractiveness assessment which features three research methods: survey method with the use of the semantic differential, the method of point bonitation and the landscape entropy method. Throughout the analysis conducted, the level of landscape attractiveness of the quarries was determined according to four classification groups: very attractive quarry landscape (I), attractive quarry landscape (II), little attractive quarry landscape (III) and unattractive quarry landscape (IV). [ABSTRACT FROM AUTHOR]

Suitability evaluation plays an important role in the land reclamation. This paper deeply elaborates the goal of land reclamation of Gol-e-Gohar Iron Ore Mine and the principles of suitability evaluation. This was divided into four evaluation units that were assessed, respectively, by selecting evaluation factors. According to the destruction forecast, the destroyed land includes four parts: open-pit slope, open-pit bottom, dump slope and the land for roads. We developed an improved method, i.e. limit comprehensive conditions method, based on the current research achievements. The results show that the proposed method is more applicable and easier to handle. [ABSTRACT FROM PUBLISHER]

With approximately 450,000 hectares of mine land pending reclamation, surface coal mines present an opportunity for large-scale grassland establishment to benefit wildlife. Herein, an alternative reclamation technique is presented that encourages a transition from typical reclamation to wildlife-friendly reclamation. Efficacy of typical, wildlife-friendly and hybrid seed mixes was compared and results indicate that wildlife-friendly mixes met vegetative cover requirements for reclamation in Kentucky. Results demonstrate that alternative methods to typical reclamation have potential to establish large areas of grassland habitat in Appalachian coal regions. Partnerships among mining companies, oversight entities and resource managers are needed to facilitate a transition to wildlife-friendly reclamation. [ABSTRACT FROM PUBLISHER]

Cut-off grade – a criterion used to discriminate ore from waste – has direct impact on mineable reserves and average grade of the materials that must be processed. The most comprehensive method for determination of optimum cut-off grades in metal deposits with the goal of maximising the net present value is provided by Lane’s algorithm. Lane’s algorithm includes income and the production costs of the final product, mining, processing and refinery capacities and grade distribution of the ore deposit, but he did not consider the reclamation costs and incomes. This study provides a model for determination of cut-off grades in open-pit mines. In this model, in addition to costs associated with management and reclamation of waste dumps, tailing dam and pits, possible incomes from reclamation are also considered. Developed model has been verified by data gathered from Gol-Gohar iron mine of Iran and results indicated that there is some important improvement in mine project goal. [ABSTRACT FROM AUTHOR]

The spontaneous establishment of plants on reclaimed spoil heaps and the relationship between their establishment and the occurrence of those same species in the surroundings were studied along the edge of a post-mining site. The study area extended 6.2 km around the perimeter. Study plots 100 × 100 m were situated both inside and outside the edge. Vascular plants considered as target and alien species were recorded in each plot using a semi-quantitative abundance scale. There were 90 target and 16 alien species recorded as spontaneously occurring outside and/or inside the edge. Of this number, 19 (i.e. 21%) target species were recorded outside the mine and four (5%) target species were recorded only on the heaps. Thus, 67 (74%) were common to both the surroundings and the post-mining site, suggesting that about two-thirds of the target species were able to colonise the post-mining site from the surrounding environs within 13–15 years since reclamation. Ordination analysis indicates that vegetation outside and inside the edge does not differ significantly. Colonisation clearly was supported by the fact that the reclamation was not done in a monotonous way, but rather emphasising a mosaic of woodland and grassland patches. [ABSTRACT FROM AUTHOR]

Oil sands surface mining operations in northeastern Alberta have created a substantial area of land needing to be reclaimed. Historically, these lands were a mosaic of uplands and boreal wetlands, particularly peatlands. While protocols for upland reclamation are well-defined, protocols for peatland reclamation are still in development. Two major concerns for peatland reclamations are (1) the ability of wetland plants to tolerate the increased sodicity present after surface mining and (2) the potential for the invasion of aggressive wetland plants, such asTypha latifolia, that could crowd out peatland plants and hinder the development of a peat layer. This study addresses these concerns by quantifying the response ofT. latifoliaseedlings to a sodium gradient. In the lowest two concentrations (0 and 300 mg L−1), there was about 100% survival rate as compared to about 56% at sodium concentration of 2400 mg L−1. At 300 mg L−1,T. latifolialeaf health began to decrease, and at 600 mg L−1, the health, plant height and the biomass aboveground decreased substantially. Our findings suggest thatT. latifoliapopulations might be kept in check by keeping sodium concentrations within a range between 300 and 600 mg L−1. [ABSTRACT FROM AUTHOR]

The Athabasca Oil Sands of Northeastern Alberta, Canada, are primarily recovered by surface mining operations. These areas are required by regulation to be reclaimed at mine closure. Recent cuts in the proposed borrow areas for cover material have revealed unusual deposits of hydrocarbons at quantities exceeding clean soil guidelines in the surficial materials. This article outlines recent work in characterising the hydrocarbon composition and groundwater leaching potential of this surficial bitumen. Characterisation consisted of field sampling with analysis by standard Canadian chromatographic methods. An initial investigation of contaminant mobility and biodegradability was conducted using a custom unsaturated soil column leaching experiment. Hydrocarbons were found to be primarily above C30. Concentrations greater than C60 were approximately 10 times those below C60. As expected, minimal leaching occurred, suggesting a minimal risk to groundwater. This result provides meaningful evidence that the material can be directly placed for reclamation. This option in turn represents a meaningful saving in terms of cost, effort and energy for the mine operators. [ABSTRACT FROM PUBLISHER]

Vegetation cover of the landscape plays an important role in the transformation of solar energy and the formation of microclimate in the landscape. A study carried out in the Velká podkrušnohorská brown coal dump (Czech Republic) focused on the impact of the structure and functions of landscape cover on temperature and humidity properties in nine localities with various states of vegetation cover. The development of temperature and relative humidity measured in various levels (temperature and relative humidity at 2 m and at canopy level; temperature on soil surface and at the depth of 0.1 m below soil surface) were assessed for the period of 1 July 2010–14 July 2010 and an evaluation of the Landsat 5 TM satellite data, collected on 10 July 2010, was carried out. Temperature development varied between the individual localities mostly at soil surface and in the ground; however, air temperatures and humidity were very similar at a height of 2 m. Extreme values of temperatures were measured on surfaces lacking vegetation cover or covered with sparse vegetation, in particular. On the basis of satellite data analysis, we determined the differences between the amounts of vegetation, temperatures and humidity values depending on the type of landscape cover and the stage of reclamation. The study results proved the significant impact of vegetation on the transformation of falling solarenergy and the formation of microclimate, and thus the importance of fast regeneration of functional vegetation cover in the surfaces newly forming in former brown coal mines. [ABSTRACT FROM AUTHOR]

In India, coalmine overburden (OB) dumps are reclaimed by forestry reclamation approach (FRA), thus selection of appropriate tree species is essential for the reclamation success. In the present study, screening of tree species was done based on natural mycorrhizal association, metal tolerance, and amelioration of minesoil properties. The study showed that tree plantation improves the moisture content, bulk density, pH, and the overall nutrient contents of minesoils. Trees possessing high levels of mycorrhiza colonisation (Dalbergia sissoo, Acacia auriculiformis and Cassia seamea) were found to be most suitable for FRA. The study infers that the stress condition of minesoils encourages higher mycorrhizal colonisation than natural soil. Acidic pH in minesoils increases the bioavailability of metals but their concentrations were found within toxic limits. The results of this study underscore the need for close monitoring of trace elements in reclaimed OB dumps. [ABSTRACT FROM AUTHOR]

Extraction of oil sands in the relatively dry Western Boreal Plains near Fort McMurray, Alberta, destroys the natural surface cover including fen peatlands that cover upto 65% of the landscape. Industry and environmental monitoring agencies have questioned the ability to reclaim fen peatlands in the post-mine landscape. This study proposes a conceptual model to replace fen systems with fen peat materials supported by groundwater inflow from a constructed watershed. A numerical model is used to determine the optimum system geometry, including the ratio of upland to fen area, thickness and slope of sand materials, and thickness of peat and of the liner that would result in flows that sustain peat wetness to a critical threshold soil water pressure of -100 cm of water at a peat depth of 10 cm. We also test the sensitivity of the system to variations in the value and spatial configuration of the hydraulic conductivity (K) of locally available materials. The optimal conditions were achieved using an upland area at least twice that of the fen, underlain by a sloping (3%) layer of fine-grained material with hydraulic conductivity (K) of 10-10 m/s, that maintains lateral groundwater flow in a sand layer with K of 10-4 to 10-5 m/s. Using daily climate inputs that included 1998, the driest summer on record, the model suggests that adequate wetness can be sustained in the fen for the growing season, and that the extent of water table recession was similar to undisturbed systems during that period. [ABSTRACT FROM AUTHOR]

Colloid mobility has been tied to contaminant transport in many agricultural soils, and may be a factor in reclaimed mine soils as well. Before contaminant transport can be predicted, the actual patterns in colloid generation and transport following disturbance needs to be elucidated. A site in the Appalachian region of southwest Virginia was chosen to observe colloid transport within natural forest soils (F), reclaimed soils (R) and reclaimed soils underlain by spoil material (RS). A fourth treatment included the application of lime-stabilised biosolids to separate RS monoliths (RSB). These intact soil monoliths were leached with de-ionised water at a rate of 1.0 cm/h for at least 2 pore volumes. Total eluted colloid loads were greatest within natural forest (F) soil monoliths (2205 mg), followed by R (1460 mg) and RS (76 mg) monoliths. The addition of biosolids (RSB) induced greater colloid transport (871 mg) compared to RS monoliths not receiving biosolids. This was likely due to an increase in pH and EC from the applied biosolids. The results suggested that colloid and potentially contaminant transport should indeed be a concern in soils disturbed by mining activities, but predicting the magnitude and patterns of colloid behaviour may be difficult due to variations in physical and chemical properties of the reclaimed soils. [ABSTRACT FROM AUTHOR]

This article proposes eco-protective countermeasures that may serve as theoretical reference for post-mining eco-rehabilitation of the Xiangshui coal mining area, Guizhou, China. These countermeasures were developed from baseline survey and assessment data for the eco-environment including plant communities, soil types, physical and chemical properties, water and soil loss, status quo, etc. [ABSTRACT FROM AUTHOR]

Mine reclamation is an integral part of the mineral development process. The selection of land use after the mine closure is a difficult decision, which is complicated further because of the variety of parameters that must be taken into account trying to provide the local community with a viable development plan. Conventional methods used for reclamation planning are characterised by the lack of data integration and by time-consuming analysis. In this study, we propose a spatial decision-support system (SDSS) that minimises these problems, as data integration and analysis are offered within one computerised environment. A geographical information system and multi-criteria decision-making methods, based on binary integer linear programming models, have been integrated to select the appropriate land use in different parts of a post-mining area taking into account social, technical, economic, environmental and safety criteria. The proposed SDSS was used for the selection of the optimal landscape reclamation strategy of the Amynteon lignite surface mine located at West Macedonia Lignite Centre, Northern Greece. On the basis of developed mine maps, the model variables are assessed and incorporated into the objective optimisation function. Emphasis is placed on the spatial diversification of the model variables. The application demonstrates that the decision-support system allows the mining company to determine in an efficient way the specific land use (agricultural land, forest, recreational area and industrial zone) that is considered the most suitable for every part of the study area. [ABSTRACT FROM AUTHOR]

Excess compaction occurs through the use of traditional surface mining reclamation techniques, resulting in low infiltration rates and subsequently high peak flows and runoff volumes. The incorporation of loose-dumped spoil into the reclamation process has been shown to promote tree growth; however, designers have little information regarding the probable hydrologic consequences (PHC) associated with this spoil disposal method. To better understand the hydrologic effects of reclaiming mined lands using loose-dumped spoil, curve numbers (CN) were developed for both a steeply sloping, forested watershed in eastern Kentucky and six, 0.4 ha test cells comprised of three types of loose-dumped spoil: (1) brown, weathered sandstone, (2) grey, unweathered sandstone and (3) a mixture of both sandstones and shale. The spoil was placed in accordance with the Forestry Reclamation Approach (FRA). Results of this project indicate that the mean CN for loose-dumped spoil was equivalent to the mean CN for the forested watershed. [ABSTRACT FROM AUTHOR]

Much of the land reclaimed since enactment of the 1977 Surface Mining Control and Reclamation Act is over-compacted. Excessive compaction in replaced growth media is detrimental to establishment of trees. If trees are to be grown on reclaimed sites, excessive compaction must be alleviated. Dry bulk density and penetration resistance can be used to indicate the level of compaction in replaced growth media. The University of Kentucky has developed reclamation test cells at a surface mine to determine the impact of organic soil supplements on selected soil physical properties of reclaimed sites. The organic soil supplements being evaluated include hardwood bark and straw and manure. Data were collected at the test cells for dry bulk density, maximum penetration depth and penetration resistance. The data show no statistical evidence that applying organic supplements has a major effect on selected soil physical properties in replaced growth media. [ABSTRACT FROM AUTHOR]

An evaluation of soil quality, which integrates biological, chemical and physical processes, would be beneficial to regulators as well as mining companies when making reclamation decisions. Coal mining regulations require that industry perform soil sampling and submit laboratory results in order to determine pre-mine and reclaimed soil quality. A rapid and accurate biological soil quality method, such as one-day CO2 (1-day CO2) analysis, can be used to determine soil microbial activity which is related to the soils' ability to sustain nutrient cycling. Our objective in this study was to compare native and reclaimed soils from surface-mine operations in order to assess the effectiveness of the 1-day CO2 method as a tool for determining biological soil quality. Soil samples were taken from sites that visually had poor and well-vegetated reclaimed areas of a surface-mine operation as well as an undisturbed native site. Chemical, physical and biological indicators were compared to 1-day CO2 analysis for microbial activity. Results indicate that the biological soil quality indicators as summarized by 1-day CO2 analysis are a more sensitive indicator of soil health on the reclaimed soils tested than chemical analysis alone. One-day CO2 analysis can be a useful additional tool for regulators and mining companies when assessing the soils ability to sustain plant growth and evaluate reclamation success. [ABSTRACT FROM AUTHOR]

Opencast mining results in severe destruction of the landscape due to the formation of overburden dumps and voids at mining sites, increased erosion, altered aesthetics and an increased pollution load onto the surroundings. Reclamation of these mine dumps forms an integral part of environmental management plan for any mining project. An advance understanding of the properties of mine soil (e.g. rock geochemistry, rock depth profiling) is important in the preparation of reclamation and closure plans. The studies undertaken in the Central Coalfield Limited (CCL) KD Heslong opencast project, revealed that the bioavailability of toxic metals depends on the physico-chemical characteristics of mine soil, and that bioaccumulation of toxic metals varies among tree species. In the nutritionally poor mine soil, the plant species Dalbergia sissoo, Cassia seamea, Acacia mangium and Acacia auriculiformis were found growing satisfactorily. Addition of topsoil and liming in the plantation pits was found to be essential and, if possible, incorporation of acid neutralizing materials such as fly ash should be undertaken. [ABSTRACT FROM AUTHOR]

Surface mining in West Virginia has disturbed large tracts of forested land. In the 1930s to 1960s, reclamation generally involved replanting of trees on mined sites, but revegetation practices gradually evolved into seeding of forages for erosion control as federal and state laws were enacted in the 1970s. Reforestation of mined lands has recently become an important issue and both federal and state regulatory agencies are returning to forestry as a preferred post-mining land use. This study evaluated tree species recruitment and growth on three, 20-year-old, surface mined areas that were not transplanted with trees. Three transects of 150 m at each site extended across three positions: (1) the flat top after coal removal; (2) the outslope down from the flat top where soil and weathered rock materials had been pushed down the hill; (3) the undisturbed forest. Tree canopy cover and herbaceous cover were determined at 1.5 m intervals along the transect line, and tree density and diameter at breast height were measured for each species located in a plot 2.3 m wide along the line. Soil samples were taken to a depth of 25 cm at 15 m intervals along transects. Soils in all positions generally had loam textures, and soil pH ranged from 4.6 to 6.0 on undisturbed and outslope positions to 6.1 to 6.6 on flat tops. Soils were noticeably thinner and denser on flat tops than in other positions. Undisturbed forests averaged 85% canopy cover and were dominated by tuliptree (Liriodendron tulipifera L.), red maple (Acer rubrum L.) and sugar maple (Acer saccharum Marsh.), with minor contributions from red oak (Quercus rubrum L.), black gum (Nyssa sylvatica Marsh.), sourwood (Oxydendrum arboreum (L) DC), sassafras (Sassafras variifolium (Nutt. Nees) and hickory (Carya spp.). Outslopes had primarily red maple, black birch, tuliptree, sourwood and black locust (Robinia pseudo-acacia L.). Flat areas were dominated by herbaceous cover with red maple and black locust being the dominant trees. Areas seeded with herbaceous plants showed low numbers and cover by trees, while areas not seeded with herbaceous plants were almost as heavily covered by trees as undisturbed areas. New guidelines are being developed to aid survival and growth of mid- to late-successional trees on newly reclaimed sites. These include less compaction of soil materials and seeding less aggressive forage species where trees will be planted. [ABSTRACT FROM AUTHOR]