Spoil Dump Research Articles

Eco-restoration approach for mine spoil overburden dump through biotechnological route.

The overburden dumps which are created during the process of mining are devoid of supportive and nutritive capacity for biomass development. Restoration of these overburden dumps requires the establishment of a self-sustaining soil-plant system, for which a restoration strategy is needed to accelerate the natural processes of ecosystem development. For eco-restoration of a coal mine spoil dump, National Environmental Engineering Research Institute developed an ecofriendly multidisciplinary approach to restore the fertility of the mine spoil overburden dump. In this regard, an experiment was conducted to restore the fertility of the overburden dump in an area of 20 ha at Durgapur in India. To reclaim the dump, the IBA (integrated biotechnological approach) was used. The integrated biotechnological approach involves the utilization of industrial waste ETP sludge (effluent treatment plant sludge) to support the nutritive capacity for vegetation establishment, inoculation, and isolation of Azotobacter, Bradyrhizobium, and VAM (vesicular arbuscular mycorrhiza) spores of Gigaspora and Glomus species along with suitable indigenous trees of ecological and economic importance. The findings of the experimental study revealed that amendment of the mine spoil with organic amendment at 50 t/ha improved the nutrient, microbiological, and physicochemical properties of the coal mine spoil and reduced the toxicity of heavy metals due to increased organic carbon content of the organic amendment effluent treatment plant sludge. Thus, amendment of the effluent treatment plant sludge and biofertilizer application provided better supportive material for the growth of different plant species which resulted into momentous biomass (aboveground biomass and belowground biomass) production thereby improving the productivity and fertility of the mine spoil dump in a short span. Thus, using IBA, the ecology and biodiversity of the area was conserved. It also helped to maintain the aesthetic environment surrounding the mine site.

Substrate-specialist plants for restoring vegetation in post-mining gypsum substrates

Restoration in degraded gypsum areas is challenging due to physical-chemical soil characteristics that limit plant development. Facilitation mediated by the stress-adapted gypsophytes may be a key process in restoration because it potentially favors the establishment of lower stress-adapted species underneath, promoting plant succession. This study aimed to assess the suitability of the gypsophyte Gypsophila struthium Loefl. for restoring vegetation in gypsum mines, focusing on its role as a pioneer species that may act as an ecosystem engineer and hence as a nurse plant. We conducted a vegetation survey in a gypsum mine in NE Spain, in plots where the original topsoil was reinserted in different years after the mineral extraction to study plant community succession and reorganization through time. Complementary, we set a sowing and planting experiment in a gypsum spoil dump to assess how G. struthium may positively affect soil and micro-environmental conditions and, consequently, may act as a nurse species facilitating plant establishment and development. To test the nurse role of G. struthium, we sowed seeds and planted seedlings of Helianthemum squamatum (L.) Pers. and Stipa lagascae Roem. & Schultz under the canopy of adult individuals of G. struthium, and in the bare soil. We found that G. struthium appeared as a pioneer shrub in the restored gypsum mine and accumulated plant diversity in the local vicinity in mature plant communities. This shrub had a positive effect on seed germination and seedling growth of the test species in the experiment and improved soil and micro-environmental conditions under its canopy. Therefore, we recommend two non-exclusive actions to enhance restoration in post-mining gypsum substrates: (1) to promote the establishment of the pioneer plant G. struthium by improving the physical-chemical and biological soil properties through the re-insertion of the original topsoil that contains propagules of the former community; (2) to apply active restoration actions, using G. struthium as a nurse plant through sowing seeds or planting seedlings of other species of interest under its canopy.

A review of the impacts of pumped hydro energy storage construction on subalpine and alpine biodiversity: lessons for the Snowy Mountains pumped hydro expansion project

ABSTRACTThe Australian government’s proposal to expand the Snowy Hydro Scheme to include a second pumped hydro energy storage (PHES) system, and support for feasibility studies for PHES in Tasmania, offer an opportunity to incorporate more intermittent renewable energy generation into the National Energy Market. However, the infrastructure construction required for PHES expansion may have negative effects for biodiversity in subalpine and alpine areas. To identify the potential effects of PHES on biodiversity in Kosciuszko National Park (KNP), this systematic literature review assesses: (i) the key environmental disturbances likely to arise from PHES construction; and (ii) the specific impacts of these construction processes on biodiversity in subalpine and alpine environments. We find that the effects of PHES construction-related disturbances are likely to be negative for subalpine and alpine biodiversity, with impacts including the proliferation of exotic flora, habitat loss resulting from vegetation clearing, altered landscape hydrology and reduced water quality. Management recommendations to limit these impacts are provided and further research is recommended to assess: (i) the effects of PHES on fish populations in alpine reservoirs; (ii) the utility of spoil as artificial habitat for endemic fauna; and (iii) the chemical and physical impacts of spoil dumping in alpine reservoirs.

Reclamation of coalmine spoils with topsoil, grass, and legume: a case study from India

Accretion of carbon (C) and nitrogen (N) content in reclaimed mine soil is a major objective to restore mine soil fertility. The present study investigated the impact of grass and legume seeding in fertility enhancement, nutrient accumulation, and accretion of C and N pool during the early stages of reclamation. Four land covers were studied—unreclaimed mine spoil dump, topsoil dump, and 2-year-old coal mine spoil dumps revegetated with legume (Stylosanthes hamata) and grass (Cenchrus ciliaris). Results showed that above- and below-ground biomass of legumes as well as biomass C and N contents were significantly higher than grass. Reclaimed mine soils under legumes cover had greater soil organic matter (SOM) (42%), soil organic carbon (SOC) (66%), available N (79%), and total N (62%) than the applied topsoil. The rates of SOC (1.57 Mg SOC ha−1 year−1) and total N (0.47 Mg N ha−1 year−1) accumulation were higher under legume than the grass. Soil CO2 flux was in the order of legume (2.34 ± 0.27 µmol CO2 m−2 s−1) > grass (2.17 ± 0.19 µmol CO2 m−2 s−1) > topsoil (1.23 ± 0.19 µmol CO2 m−2 s−1). Total cost of reclamation was US$ 6761 ha−1, out of which 59% was contributed by technical reclamation and 41% by biological reclamation which includes aftercare and maintenance for 2 years. Legumes showed advantages over the grass species to restore mine soil fertility. Therefore, this study recommends the application of legumes as an initial colonizer to reclaim coal mine spoils.

Vetiver grass is a potential candidate for phytoremediation of iron ore mine spoil dumps

Vetiver grass, Chrysopogon zizaniodes (L.) Roberty, is a perennial C4 grass, valued for its aromatic essential oil in the roots. Vetiver attracted global attention as a natural means for diverse environmental applications including detoxification of degraded soil and water. A pilot study was conducted to investigate its potential to rehabilitate iron ore spoil dumpsites generated from the Joda East Iron mine located in Odisha, India. Four diverse genotypes of vetiver: S2 (diploid variety), S4 (tetraploid derivative of S2), TH (originated from Thailand), BL (a broad leaf) were grown over a period of 12 months to observe their growth performance, metal tolerance and metal uptake. The shoot/root length, photosynthetic pigments – chlorophyll, carotenoid and biomass production of plants grown on iron mine soil decreased initially as compared to the control plants grown on garden soil. At the end of 12 month the plants showed evidence of normal growth and appeared healthy. Scanning electron microscopy (SEM) and Perl’s Prussian blue stain confirmed the uptake and localization of Fe in the roots and shoots of the plants grown on mine soil. In addition Zn, Mn, Cr and Cu, was detected in the plant tissues. Such accumulation of metals in plant tissues led to oxidative damage induced by reactive oxygen species (ROS). As a consequence the activities of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPOD), glutathione reductase (GR) and glutathione peroxidase (GPX) were increased. Based on the results it can be inferred that vetiver grass per se can tolerate high concentrations of Fe along with other heavy metals in its tissues. Such potential vary across the four genotypes, and the genotype BL followed by S4 can be claimed of paramount importance in terms of phytoremediation. Thus vetiver grass can be effectively used for rehabilitation and soil stabilization of sites contaminated with high levels of heavy metals, particularly Fe, Mn, Zn and Cr.

Развитие нормативной базы в области обеспечения устойчивости бортов и уступов карьеров, разрезов и отвалов

Развитие нормативной базы в области обеспечения устойчивости бортов и уступов карьеров, разрезов и отвалов

Assessment of the Influence of Dredge Spoil Dumping on the Seafloor Geological Integrity

The European Marine Strategy Framework Directive requires the development of suitable indicators for regular reporting on the environmental state and achievement of a good environmental status of EU’s marine waters by 2020. The development of indicators for determining seafloor integrity and its possible disturbance by human activities have so far largely ignored the geological properties of seafloor. This paper presents a study of Vuosaari and Uusikaupunki-D offshore dumping sites in Finland, the northern Baltic Sea. Full coverage multibeam bathymetry and relative backscatter data, and a number of sediment cores were collected over the sites. The areas covered by dumped dredge spoil stand out in the multibeam images because of their irregular surface and elevated backscatter. The short gravity cores were studied for lithology, and in 1-cm slices for 137Cs activity, organic content, and grain size distribution. The dumped material is represented in the cores by the gravelly mud lithofacies with massive texture and angular coarse particles. The dumped material is coarser, less sorted and has higher kurtosis compared to natural sediment due to the admixing of blasted rock during the dredging activities, and limited sorting during fall through the water column upon dumping. Dispersed dredge spoil, which was suspended in the water column during the dumping activities or reworked from the dumped material mounds and redistributed along the seafloor soon thereafter, was deposited over a wide area as a thin layer that is not necessarily readily identifiable by visual inspection in the cores. Cesium activity helped distinguish the dumped material from the 137Cs-enriched natural sediments deposited after the 1986 Chernobyl disaster. Considering that the dumped material at many of the coring sites in the Vuosaari dumping area is covered by natural sediment, it probably is largely stable. In contrast, dumped material at the shallower Uusikaupunki-D site has slumped down to an adjacent channel and is likely being redistributed by near-bottom currents. Based on the findings of the study, a protocol for the assessment of the geological integrity of seafloor, its anthropogenic change due to dumping, and its potential recovery is proposed, as required by the Marine Strategy Framework Directive.

Spoil characteristics under five years old native woody plantations and unplanted dump in dry tropical environment, India.

Present study was conducted to investigate spoil characteristics under 5-yr old high-density plantations of three native trees (Albizia lebbeck A. procera and Tectona grandis) and one fast growing woody grass (Dendrocalamus strictus) species on coal mine spoils and same age unplanted mine spoil dump at the same area. We examined physical characters such as soil bulk density, water holding capacity, soil texture (sand, clay and silt) and chemical characters such as pH, total nutrients (C, N and P) and exchangeable cations (Ca, Mg, K and Na) in chronosequence of spoil depth (0-50 cm) at 10 cm interval under planted stand of each selected species and unplanted dump. A significant effect of plantations on physico-chemical characteristics (except soil bulk density) of mine spoils was found. Among species, A. lebbeck exhibited substantial improvement in mine spoil soils followed by D. strictus, A. procera and T. grandis plantation. Although, chemical characteristics especially total concentrations of soil C, N and P and their ratios were significantly different due to species and spoil depth, indicating plantations of all species have abilities to improve soil chemical qualities at young stage of establishment. Compared to unplanted dump, plantation of A. lebbeck showed highest concentrations of total nutrients (C, N and P) and exchangeable cations with respect to spoil depth followed by D. strictus, A. procera and T. grandis, which confirms that some species have suitable qualities for the modification of spoil characteristics during rehabilitation process.

Evaluation of the Munich Plastic Sediment Separator efficiency in extraction of microplastics from natural marine bottom sediments

AbstractThe Munich Plastic Sediment Separator (MPSS), proposed by Imhof et al. (), showed its high efficiency in extracting microplastics (MPs) from natural sediment samples preliminarily cleaned and then enriched by MPs in laboratory. We tested the efficiency of the MPSS, assembled at the Atlantic Branch of P.P.Shirshov Institute of Oceanology (Kaliningrad), using unprepared natural bottom deposits of different types collected in the Baltic Sea. The tests that were performed included spikes of sediments with artificial reference particles (ARPs) and the sediment samples analyses with two separate methods of extraction and determination of MPs content in residuals of MPSS. While the ARP extraction efficiency from natural sediments by the MPSS was really high (97.1% ± 2.6%; p = 0.05; n = 14; confidence interval, t‐distribution), the extraction efficiency of marine MPs was considerably lower (13–39%) than that obtained with a modification of the method previously published by NOAA. The remaining marine MPs were found in the spoil dump and in the bulk solution fractions of the separator, indicating that MPs were not perfectly cleaned from sediment particles, probably, due to presence of organic matter. It is concluded that the MPSS application for quantitative MPs analysis requires further testing and elaboration of standardized extraction procedures.

Optimizing coastal and marine spatial planning through the use of high-resolution benthic sensitivity models

Effective management of coastal and marine resources requires knowledge of how community sensitivity varies spatially. With this in mind, we developed a benthic sensitivity index (SI), based on the distribution and abundance of five ecological groups that can be used to assess community tolerance to organic enrichment and other disturbances. The index, projected as a high-resolution map, ranks communities from those dominated by sensitive and ecologically important species (i.e. low SI values) to those composed mainly of tolerant and/or opportunistic species (i.e., high SI values). Applying our model to a multiple-use case study in southeast Brazil, we were able to show considerable variability in the sensitivity of communities across the study area that was relatively stable over time. This allowed us to evaluate the possible direct (i.e., spatially overlapping) and indirect effects (i.e., cumulative changes to the physical environment) of a range of activities on sensitive and ecologically diverse benthic communities. Our approach and the resulting high-resolution maps hold promise for a range of spatial planning applications, including the development of coastal infrastructure, assessments of the representativeness of marine protected areas and other activities such as the selection of appropriate locations for dredge spoil dumping. Overall, we present a novel and transparent way of extrapolating limited survey data to provide spatial and temporal information on the sensitivity of benthic communities in multiple-use coastal and marine areas.

At-sea dumping of dredge spoil: an overview of the Australian policy and legislative framework

ABSTRACTThe increase in port development along the Queensland coast, and the associated dredging activity, has led to increased environmental concerns for the health of the Great Barrier Reef (GBR). While such impacts are of particular immediate concern for the GBR region, the issues surrounding dredging and dumping of dredge spoil are common to many other coastal regions in Australia and elsewhere. In this article, we review the current Australian policy and legislation affecting the dumping at sea of dredge spoil and the incentives this creates in terms of minimising damage. We find that the current complex framework may not necessarily provide appropriate incentives to minimise damage once approval has been obtained, although more recent policy interventions may help encourage innovation in more environmentally friendly actions. We also review the potential for other incentive-based management systems to limit environmental damage from dredging, drawing on the experiences in fisheries and marine biodiversity conservation.

Slope Stability Analysis for the Design of a New Lignite Open-Pit Mine

The paper presents geotechnical engineering studies for the design of a new lignite open-pit mine in central Poland. The lignite deposit occur in a deep tectonic rift formed in Mesozoic rock characterized by complex geological conditions. The rift is approximately 10km long, 1km wide and 50-250 m deep and filled with Neogene and Quaternary sediments. The design of the open-pit mine required geotechnical analysis to reveal possible problems that may occur during its construction and operation. The author of this paper had opportunity to perform slope stability studies and geotechnical analyses within the project conducted by Poltegor-Institute. The calculation procedure enabled determination of slope stability on the design of excavation and spoil dump. It included 21 analyses using Flac v.7 of which 14 regarded the slopes of the pit, 6 the slopes of the external spoil dump and one covered both areas. The results indicated that the factor of safety Fs ranges 0.75-1.65 for the pit and 1.12-1.60 for the dump. In risk areas slope inclination were lowered due to likelihood of developing of landslide processes. These included spoil dump area close to S-8 road. Due to relatively limited geotechnical data in same areas especially on northern slope and western part of spoil dump detailed geotechnical investigations will be necessary. The instability problems can be caused by the groundwater conditions and the presence of high compressibility organic peats in the spoil dump bedrock layers. Comprehensive identification and monitoring of geotechnical risks for the mine slopes and storage of overburden should be a continuous process. This activity should start from the beginning stages of construction and should be conducted also during exploration and continuing to mine final reclamation to reduce potential natural hazard impact on mining and the natural environment.

Artificial boulderfield yields a surprise: The Smoky Mouse in Kosciuszko National Park, Australia

SummarySpoil dumps in the subalpine and montane environments of Kosciuszko National Park in far south‐eastern Australia are modified landscapes which in the past were considered to have little faunal value. Recent finds (2010–2011) of the critically endangered Mountain Pygmy‐possum (Burramys parvus) have resulted in a reconsideration of the importance of such landscapes to fauna. Such re‐evaluation has been translated into on‐ground actions, including the construction of an artificial boulderfield on one spoil dump as habitat targeting Mountain Pygmy‐possum in rehabilitation works. Trapping 7 and 19–20 months, respectively, after these works has so far not recorded this Pygmy‐possum. However, it led to the discovery of another critically endangered species, the Smoky Mouse (Pseudomys fumeus). Two males (with three recaptures) and one female were captured in 250 trapnights in November 2015 and an additional male in 600 trapnights in December 2015. The capture of this enigmatic species is highly significant as it is the first live capture of the species in the park and it is only the second locality in which live captures have been made in New South Wales since 2001. The location of the Smoky Mouse in spoil dumps further emphasises how these areas provide existing and potential habitat for native fauna species.

Impact of coal mining on soil properties and their efficient eco-restoration

Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. Mining of mineral resources results in extensive soil damage, altering microbial communities and affecting vegetation leading to destruction of vast amount of land. In the present study, attempts have been made to assess the impact of coal mining on soil nutrients and their efficient restoration through different combination of soil amendments. The physico-chemical and biological properties of mine spoil before and after treatment were analysed. Results indicated that the applications significantly improved the physico-chemical and microbiological properties (which were practically absent) of the coal mine spoil dump. A great variety of microorganisms have been found in mine wastes and microbiological processes that are usually responsible for the environmental hazard created by mine wastes. The findings of this study can be utilised by the mine management programs in the large scale revegetation of several adjacent coal mining overburden dumps for eco-friendly mining.

Surficial geology and geomorphology of the Kumtor Gold Mine, Kyrgyzstan: human impacts on mountain glacier landsystems

ABSTRACTA 1:50,000 scale map of the surficial geology and geomorphology of the mountain glacier landsystem and the human impacts of the Kumtor Gold Mine operations in the Akshiirak massif was compiled from a 0.5 m resolution pan-sharpened image from Digital Globe's WorldView-2 platform dated 5 September 2014. The map depicts 11 surficial geology units, 6 of which are classified according to natural genetic origins and 5 relating to recent human interference with glaciological and land surface processes. When compared to historical imagery the map records a number of important, not unrelated, cryospheric responses to mining activity, including: (a) the triggering of human-induced glacier speed-up events or surges due to dumping of mine spoil on receding and thinning glacier snouts; (b) the reactivation by internal creep of buried glacier ice due to the expansion of spoil dumping onto down valley areas of ice-cored moraine; and (c) accelerated ice drawdown and significant incursions of ice into the mine pit walls due to the artificial removal of substantial areas of glacier ablation zones.

Rapid advance of two mountain glaciers in response to mine-related debris loading.

Rapid glacier advance is known to occur by a range of mechanisms. However, although large‐scale debris loading has been proposed as a process for causing rapid terminus advance, it has rarely been observed. We use satellite remote sensing data to observe accelerated glacier terminus advance in response to massive supraglacial loading on two glaciers in Kyrgyzstan. Over a 15 year period, mining activity has led to the dumping of spoil of up to 180 m thick on large parts of these valley glaciers. We find that the termini of these glaciers advance by 1.2 and 3.2 km, respectively, at a rate of up to 350 m yr−1. Our analysis suggests that although enhanced basal sliding could be an important process, massive supraglacial loads have also caused enhanced internal ice deformation that would account for most, or all, of the glacier terminus advance. In addition, narrowing of the glacier valley and mining and dumping of ice alter the mass balance and flow regime of the glaciers. Although the scale of supraglacial loading is massive, this full‐scale experiment provides insight into glacier flow acceleration response where small valley glaciers are impacted by very large volumes of landslide debris.

Vetiver Grass: a potential tool for phytoremediation of iron ore mine site spoil dump

Vetiver Grass: a potential tool for phytoremediation of iron ore mine site spoil dump

Opencast Coal Mining Induced Defaced Topography of Raniganj Coalfield in India - Remote Sensing and GIS Based Analysis

With the advent of mining activities at Raniganj coalfield in India, the natural topography has been defaced in some elongated tracts by either excavation or dumping. This paper deals with opencast mining induced defaced topography of Raniganj coalfield, which needs to be reclaimed properly right after mining. This paper investigated intensity of defacing topography, magnitude of topographic deformations through a number of ex-situ measurement. Consequences of these topographic deformations are also investigated in this study. Through a number of ex-situ measurement based on Geographical Information System (GIS) techniques, generating contour and profiling them over the spoil dumps and excavated lows using fine resolution digital elevation data (Remote Sensing image), a total 132 (85 are abandoned and 47 are working) patches of defaced topography have been identified, which covers 43.26 sq km. surface area. Some working opencast quarries are more than 95 m deep, with an area of more than 2.4 sq km and dumped ridges are more than 60 m high (peak), with area more than 1.5 sq km. In case of abandoned mine (more than 20 years) some quarries are more than 28 m deep with area 0.99 sq km. and some of dumped ridges are more than 28 m high (peak), with area 0.29 sq km. These kinds of defaced surface remain for a long time, such quarries contain acidic logged water and spoil dump leads to acid mine drainage and erosion of loose soil particle. It deteriorates the entire land, water system of the region. The study suggests restoring land right after mining and the area made to be ecologically conformable.

Mining waste contaminated lands: an uphill battle for improving crop productivity

Mining drastically alters the physico-chemical and biological environment of the landscape. Low organic matter content, unfavourable pH, low water holding capacity, salinity, coarse texture, compaction, siltation of water bodies due to wash off of mineral overburden dumps, inadequate supply of plant nutrients, accelerated erosion, acid generating materials, and mobilization of contaminated sediments into the aquatic environment are the principal constraints experienced in mining contaminated sites. A variety of approaches have been considered for reclaiming mine wastes including direct revegetation of amended waste materials, top soiling, and the use of capillary barriers. The simplest technology to improve crop productivity is the addition of organic amendments. Biosolids and animal manure can support revegetation, but its rapid decomposition especially in the wet tropics, necessitates repeated applications. Recalcitrant materials such as “biochars”, which improve soil properties on a long term basis as well as promote soil carbon sequestration, hold enormous promise. An eco-friendly and cost-effective Microbe Assisted Phytoremediation system has been proposed to increase biological productivity and fertility of mine spoil dumps. Agroforestry practices may enhance the nutrient status of degraded mine spoil lands (facilitation). N-fixing trees are important in this respect. Metal tolerant ecotypes of grasses and calcium-loving plants help restore lead, zinc, and copper mine tailings and gypsum mine spoils, respectively. Overall, an integrated strategy of introduction of metal tolerant plants, genetic engineering for enhanced synthesis and exudation of natural chelators into the rhizosphere, improvement of rhizosphere, and integrated management including agroforestry will be appropriate for reclaiming mining contaminated lands.

Rehabilitation prioritization of abandoned mines and its application to Nyala Magnesite Mine

The issue of abandoned mine sites is a major environmental and social problem for the mining industry, communities and governments. Historical mine sites are characterized by significant environmental, health and safety problems. The aim of this study was to develop hazard maps that can assist in the prioritization of rehabilitation at Nyala Mine. The approach used involved site examination and characterization to establish the environmental conditions of the mine. Hazards at the mine were identified, scored, and rated using modified Historic Mine Site Scoring System. The scoring focused on source and exposure pathways. The developed hazard maps showed that the best approach of effectively reducing the physical and environmental hazards at Nyala Mine was to give priority to extremely and moderately hazardous pits; surface infrastructure and spoil dumps, and then to tailings dumps characterized with less physical hazards but extremely high environmental hazards. Pits and spoil materials which were found to be relatively less problematic in terms of physical hazards were to receive least attention. The use of this hazard-scoring and risk-ranking methodology coupled with the hazard maps would provide a more robust scientific basis for making sound decisions and prioritize actions that need to be taken to minimize or manage risks associated with various areas of the mine site.