The separate land disposal of coal refuse and fly ash presents difficulties throughout the Appalachian region, both in terms of disposal costs per acre and in terms of its potential environmental impacts on soil, ground water, revegetation, and slope stability. The purpose of this study was to determine how fly ash addition to coal refuse would impact on certain geotechnical properties of the refuse disposal piles, and whether the refuse-fly ash blends would be suitable as co-disposed materials. Accordingly, the compaction, permeability and shear strength characteristics of the refuse-fly ash blends were experimentally determined for varying fly ash percentages. The compaction test results indicated that, with increasing fly ash, the maximum dry density of these blends marginally decreased. The permeability test results showed that the permeability of the test specimens progressively decreased with the increase in fly ash. The shear strength results demonstrated that the addition of fly ash did not significantly influence the shear strength of the refuse. The critical factor of safety determined during slope stability analysis revealed that the tested slope geometries were stable for long term, drained conditions (using the STABGM computer program). The volume change analysis determined that there was a minimal expansion in the volume of refuse when it was blended with fly ash. However, it may be noted that all the stated results depend on a number offactors, including the nature of the refuse and fly ash used. Therefore, these findings would be specific to bulk blends of coal refuse and fly ash only. In general, this study indicates that fly ash can be beneficially reused with respect to the geotechnical properties evaluated. Co-disposal of fly ash and coal refuse may be a reasonable alternative to present disposal methods. / Master of Science

Three streams (Parker Run, Little Leading Creek and Thomas Fork) in the Leading Creek watershed, Meigs County, Ohio were impacted by active coal mining, agricultural and abandoned mined land sedimentation and acid mine drainage (AMD), respectively. An ecotoxicological evaluation was performed using physical (water chemistry and sediment depth analyses), toxicological (acute water column, chronic sediment and 35-day in situ toxicity tests) and ecological (benthic macroinvertebrate community sampling) parameters. Persistent acute toxicity (mean 48-hr LC50 of 30.3% to C. dubia) due to low pH (mean of 5.4) and high concentrations of dissolved metals (ex: Al ~ 10 mg/L) were responsible for the significantly depressed benthic macroinvertebrate community sampled in Thomas Fork. Heavy sedimentation (>30 inches), with no associated toxins, significantly decreased both abundance and diversity of benthic macroinvertebrates in Little Leading Creek. High concentrations of sodium (mean of 910 mg/L), TDS (mean of 3,470 mg/L), and periodic acute water column toxicity (mean C. dubia survival of 62% in 100% sample) were most likely responsible for the depressed benthic macroinvertebrate community observed in Parker Run. In ranking the severity of impacts, AMD was first followed by non-toxic sedimentation, and active coal mining ranked last. A catastrophic coal slurry spill significantly impacted the benthic macroinvertebrate community in Parker Run in April 1997. Six sampling stations were established to monitor the recovery of the stream's benthic community and evaluate any impact the active coal mine effluent had on the recovery time of the community. The effluent, characterized by high concentrations of TDS (~4,200 mg/L), significantly hindered benthic macroinvertebrate community recovery in Parker Run. The benthic community at the initial spill site, which was above the active mine effluent, recovered to levels measured at an upstream reference within 4-9 months. Benthic communities impacted by both the slurry spill and the effluent still had not recovered 16 months after the spill. Concentrations of TDS measured in the stream were significantly correlated (r = -0.765 and -0.649 respectively) with both EPT richness and percent C. dubia survival in water column toxicity tests. Laboratory analysis of synthetic coal mine effluent, similar in composition to that of the Parker Run effluent, was performed to determine toxicity thresholds for sodium, sulfate, TDS and conductivity. Acute toxicity thresholds were found for sodium (between 900 and 1,000 mg/L), TDS (4,200 and 6,400 mg/L), and conductivity (5,000 and 6,200 µmhos/cm). It was also determined that any toxic contribution of sulfate in solution with high concentrations of sodium (~1,000 mg/L) and/or TDS (~4,200 __ 6,400 mg/L) was secondary to that of the toxic effect of sodium or TDS in that solution. / Master of Science

Coal mining has had profound impacts in the Appalachian region, initiating a need to understand the implications of traditional and current reclamation practices on wildlife. I evaluated wildlife use of reclaimed sites of varying ages and cover types in southwestern Virginia. I compared reclaimed sites to another form of anthropogenic disturbance (clearcut) and relatively undisturbed mature forest. Birds were surveyed during early mornings throughout the breeding season in 2007 and 2008 using the point count method. Amphibians were surveyed using artificial cover, constrained-time night searches, and auditory pond surveys. Microhabitat data were collected at each sampling point and were combined with landscape-level GIS information to relate habitat characteristics and wildlife patterns. I observed 80 bird species using reclaimed areas, clearcuts, and mature forest. Pre-regulation sites (prior to the Surface Mining Control and Reclamation Act of 1977) supported the highest number of species overall. Cluster analysis identified 4 bird associations based on habitat characteristics. I developed site-specific, landscape-level, and mixed-scale logistic regression models to identify habitat characteristics that best predicted the presence of 27 species. For 18 species, mixed-scale models performed best, suggesting the importance of a multi-scale approach to habitat analysis. Salamanders were generally not detected on reclaimed areas, possibly due to the lack of soil moisture, leaf litter, and woody debris on young sites. Frogs were present in all water bodies surveyed, suggesting the importance of managing ponds and wetlands on reclaimed sites. Identifying and focusing on important habitat characteristics will help managers enhance post-mining land for wildlife. / Master of Science

Inhalation of respirable coal mine dust (RCMD) can lead to chronic lung diseases, including coal worker’s pneumoconiosis (CWP) and more severe forms such as progressive massive fibrosis. After the Federal Coal Mine Health and Safety Act was passed in 1969, limits on exposure to respirable dust were set, and the prevalence of CWP abruptly decreased. However, during the last two decades, a resurgence of the disease has been reported. Many authors have argued that the increasing numbers might be related to mining practices, including the extraction of thinner coal seams, characteristics of the mineral deposits, and more powerful cutting machines. Dust particles in coal mines are usually associated with three main sources: Coal particles are produced when the coal seam is being actively extracted. Silica and silicates are generated while cutting the rock strata surrounding the coal or during roof-bolting activities. Finally, rock dust application is the primary source of highly pure carbonates. Timely information about dust composition would allow the identification of potential dust sources and pursue efforts to control dust exposure efficiently. However, this information needs to be provided promptly since dust levels are dynamically changing through the shift. Currently, monitoring technologies such as the continuous personal dust monitor allow real-time measurements, but they are limited to total dust concentration and provide no information about dust composition. More recently, the National Institute for Occupational Safety and Health (NIOSH) has been developing an end-of-shift silica monitor. Still, technologies that offer information on dust composition in a semi-continuous manner are needed. In this work, a new monitoring concept is explored that has the potential to provide near real time data on RCMD constituents. The possible use of a portable optical microscopy (OM) combined with image processing techniques is explored as the basis for a novel RCDM monitoring device. The use of OM in different fields and the rapid development of automated image analysis reveals a clear opportunity that has not been yet exploited for mine dust monitoring applications. This thesis research consisted of two primary studies. The first was an analysis of lab-generated respirable dust samples containing the main mineralogical classes in RCMD (i.e., coal, silica, kaolinite as a proxy for silicate minerals, and a real rock dust product). Samples were imaged using a polarizing microscope and analyzed using an image processing routine to identify and classify particles based on optical characteristics. Specifically, birefringence of particles was exploited to separate coal particles form mineral particles. This is an exciting result since even such a basic fractionation of RCMD would be valuable to track changing conditions at the mine production face and enable rapid decision making. The second study was conducted to explore subclassification of the mineral fraction. A model was built to explore multiple particle features, including particle size, shape, color, texture, and optical properties. However, a simple stepwise method that uses birefringence for separating coal particles first and then classifying silica particles proved most effective. One particular challenge to the silica classification was determined to be the particle loading density. Future work to further enhance the output of the algorithm and next steps were depicted. This thesis research demonstrated that OM and image processing can be used to separate mineral and coal fractions. Subclassification of silica and other minerals using optical properties such as birefringence of particles alone was successful, but showed less accuracy. A robust sampling method that accounts for particle loading density and a more complex model with additional differentiating features might enhance the results. This approach should be considered as a potential candidate for the development of new RCMD monitoring technologies. This tool could enable better tracking of dust conditions and thus better decision-making regarding ventilation, dust controls, and operator position to reduce exposure hazards. / M.S. / Inhalation of fine particles in underground coal environments can lead to chronic lung diseases, such as coal worker’s pneumoconiosis or progressive massive fibrosis (PMF), which is the most severe form of disease. During the last two decades, the rates of reported cases of PMF in underground coal miners have more than doubled. Many authors have suggested different reasons to explain this trend, including the extraction of thinner coal deposits, mining techniques, changes in mineral content, and the use of high-powered cutting equipment. However, detailed information of specific dust constituents and monitoring the variability of dust concentrations during work shifts are needed to determine possible dust sources and comprehend the more recent changing disease patterns. A dust-monitoring system that provides accurate and timely data on specific respirable coal mine dust (RCMD) constituents would enable the deployment of effective control strategies to mitigate exposure to respirable hazards. Optical microscopy (OM) has been used for a long time to analyze and identify dust particles. More recent advances in portable microscopy have allowed the microscope analysis to be implemented in the field. On the other hand, automated image processing techniques are rapidly progressing and powerful imaging hardware has become a reality in handy small devices. OM and image processing technologies offer a path for near real-time applications that have not been explored for RCMD monitoring yet. In this work, a novel monitoring concept is explored using OM and image processing to classify RCMD particles. Images from dust samples captured with a polarizing microscope were used to build a classification model based on optical properties. The method herein described showed outstanding accuracy for separating coal and mineral fractions. Additionally, the Identification of silica particles in the mineral fraction was investigated and has proved more challenging. A particular finding suggests that particle loading density in the images plays an important role in classification accuracy.

Inhalation of respirable dust in coal mines is a serious occupational health hazard which can lead to the development of chronic and irreversible lung diseases, such as Coal Worker's Pneumoconiosis (CWP) and Progressive Massive fibrosis (PMF). After the passage of the Federal Coal Mine Health and Safety Act (CMHSA) in the late 1960's the prevalence of CWP among US coal miners decreased. However, since the late 1990's a resurgence of lung diseases has been reported, particularly in central Appalachia. On the other hand, dust monitoring data suggest that concentrations of respirable coal mine dust (RCMD) and crystalline silica have been on a downward trend. This contradiction has prompted keen interest in detailed characterization of RCMD to shed light on dust constituents-and their sources. Such information might help miners understand where and under what conditions specific sources contribute to RCMD, and how dust controls and monitoring could be enhanced to mitigate the exposure to respirable hazards. Respirable dust particles generated in coal mines are generally associated with three primary sources: the coal strata that is mined and generates mostly coal particles that could contribute for lung diseases, the rock strata that is cut along with the coal and generates most of the respirable silica and silicates, and the rock dust products that are the main source of carbonates which could produce respiratory irritations. Thermogravimetric Analysis (TGA) is one of many analytical tools that might be used for dust characterization. Its primary benefit is that it can be used to apportion the total sample mass into three mass fractions (i.e., coal, carbonates, non-carbonates) which should be roughly associated with the primary dust sources (i.e., coal strata, rock dust products, rock strata) in many coal mines. This thesis consists of two main chapters: Chapter 1, outlines the research motivation, recaps the efforts to establish a standard TGA method for RCMD, and shows results of the validation experiments that were performed in the current work to enable application of the TGA method to a large set of RCMD and laboratory-generated dust samples. In Chapter 2, 46 lab-generated samples from primary dust source materials collected in 15 coal mines, and 129 respirable dust samples from 23 US coal mines are analyzed using the TGA method validated in Chapter 1. Results for both sets of samples are presented and the mine samples are interpreted based on sampling location, mining method and region. Additionally, Chapter 3 summarizes recommendations for future work. / Master of Science / The chronic exposure to dust generated in underground coal operations represents a serious health concern among coal miners that can lead to the development of lung diseases such as Coal Workers Pneumoconiosis (CWP or "black lung). Despite of dust compliance monitoring data that have shown that the concentrations of dust have been declining, since the late 1990's the number of US coal miners diagnosed with lung diseases has been increasing, especially in central Appalachia. This contradiction has prompted keen interest in detailed characterization of respirable coal mine dust (RCMD) to shed light on dust constituents-and their sources. Such information might help miners understand where and under what conditions specific sources contribute to RCMD, and how dust controls and monitoring could be enhanced to mitigate the exposure to respirable hazards. Thermogravimetric Analysis (TGA) has been proposed as an alternative approach for dust characterization. Its primary benefit is that it can be used to apportion the total sample mass into three mass fractions (i.e., coal, carbonates, non-carbonates) which should be roughly associated with the primary dust sources (i.e., coal strata, rock dust products, rock strata) in many coal mines. This thesis consists of two main chapters: Chapter 1, outlines the research motivation, recaps the efforts to establish a standard TGA method for RCMD, and shows results of the validation experiments that were performed in the current work to enable application of the TGA method to a large set of RCMD and laboratory-generated dust samples. In Chapter 2, 46 lab-generated samples from primary dust source materials collected in 15 coal mines, and 129 respirable dust samples from 23 US coal mines are analyzed using the TGA method validated in Chapter 1. Results for both sets of samples are presented and the mine samples are interpreted based on sampling location, mining method and region. Additionally, Chapter 3 summarizes recommendations for future work.

A survey of the freshwater mussel fauna was conducted in the Powell River, Virginia, to identify critical habitat for endangered species, quantify substratum composition and coal waste deposition, and to assess population trends during the last half century. Mussels were collected as far upstream as Powell River Mile (PRM) 167.4 near Dryden, Virginia. Endangered species were collected up to PRM 144.6 at Jonesville, Virginia. The sites with greatest diversity were located furthest downstream, and there appeared to be a general decline in the number of species and diversity of mussels from downstream to upstream. Mussel densities also declined proceeding upstream, and specimens were rare above PRM 158.3 near Pennington Gap, Virginia. The highest density occurred at PRM 123.0 near the Tennessee-Virginia border, with 24 mussels/m². Collections per unit effort of sampling concurred with quadrat surveys, indicating a decline in abundance and diversity upstream. Length frequency distributions of the muckets Actinonaias pectorosa and A. ligamentina indicated an absence of smaller mussels at most sites. Sediment samples, collected in riffles at 10 sites to determine particle size distributions and the amount of coal, showed no apparent trends in waste coal from downstream to upstream; however, there were significant negative correlations between PRM location and various fractions of the substratum, indicating a longitudinal sorting of smaller size fractions. Percentages of very fine to medium sand, silt, and coal show marked increases downstream of the North Fork Powell River confluence (PRM 156.6) at Pennington Gap, Virginia. Mussel density had a slightly positive correlation with percent silt (r²=0.346, p=0.0736) but was not correlated with percent coal. Juvenile mussels of Villosa iris were placed on several types of substratum to determine differences in survival. In laboratory experiments, survival of juveniles on coal silt sometimes did not differ from that of juveniles without substratum (survival close to 100%). Survival of juveniles without substratum (93.9%), however, was significantly higher than survival (30.0-63.2%) on three sediment types from the Powell River (p< .001). In field experiments, there was a marginally significant difference in survival of juveniles between two sites (p =.070), with higher survival (47.7%) in sediments from Poteet Ford (PRM 144.6). Survival of juveniles was similar in all laboratory and field experiments. A decline in density of the mussel fauna in the Powell River over the past 15 years was apparent when compared to previous data. Contamination and siltation from coal washing facilities and abandoned mine lands are suspected of contributing to this decline. / Master of Science

Student Number: 0420801P Master of Science in Engineering. Faculty of Engineering and the Built Environment / Underground observations at a coal mine indicated failure of the immediate roof above the bords while pillars were observed to be intact. To determine the underlying causes of roof failures, careful observations and photographic recording of occurrences of roof failures have been made. Rock samples of the immediate shale roof were collected for laboratory testing to determine the rock strength and deformation properties. Numerical simulations were carried out to analyse stress and strain distributions and also to attempt to explain the guttering process. Mapping of roof failures showed that these took place mainly towards the centre of the roadways. The roof failures, termed “roof guttering”, were observed to occur violently and with little warning. Occurrence of roof guttering had a negative impact on production. Some panels are abandoned, production times have increased and safety of workers is compromised. The mine authorities initially thought that roof guttering was caused by shear failure of the rock mass. Roof bolts are therefore used as a means of primary support. No improvements have been observed. Increasing the size of pillars has not solved the problem either. It has only increased the amount of coal left in the pillars without any improvements in reducing roof failures. Stress measurement results carried out in 2001 showed that high horizontal stresses exist at the mine. The immediate shale roof was observed to be weak. Laboratory testing showed that the shale rock is transversely isotropic. Numerical modelling results indicated that there are insignificant stress concentrations towards the centre of the roadway using the elastic and transversely isotropic elastic models. Stress concentrations were predicted at the roof-pillar contact area. It is therefore expected that failure should initiate and occur at the roof-pillar contact area. The Mohr-Coulomb and Mohr-Coulomb strain softening models predicted shear failure at the roof-pillar contact area. The two models over predicted the depth and under predicted the width of failures. The extension strain criterion predicted correctly the depth and width of failures although the failures were predicted at the roof-pillar contact area while the observations indicated failure mainly towards the centre of the roads. Initiation of failure was predicted ahead of the coal face at the centre of the road position using the extension strain criterion. Although none of the constitutive behaviours predicted correctly the observed underground failures the extension strain criterion has shown the best agreement. Guttering that occurred at the roof-pillar contact was modelled successfully using the extension strain criterion. The extension strain criterion predicted initiation of failure ahead of the coal face at the road centre position. It is possible that fracture initiation could be taking place in this location ahead of the coal face, and, on blasting the rock that has been fractured falls forming a gutter at the centre of the road.

The landfilling of biodegradable waste is proven to contribute to environmental degradation. Much wood and lumber is discharged as waste from the cleared fields. These woody wastes are subsequently disposed of by burning. However, it would be preferable to dispose of them without combustion to avoid the release of carbon dioxide, one of the critical greenhouse gases. Instead of burning these woody wastes, we should recycle them as future resources. One solution to this problem is to make compost from the waste. Compost use in agriculture is increasing as both an alternative to landfilling for the management of biodegradable waste, as well as means of increasing or preserving soil organic matter. This research aimed to contribute to the identification of a system for managing the production and utilization of wood waste (Quercus rubra and Pinus sylvestris) compost for sustainable agriculture, with particular regards to carbon dioxide produced from both compost and combustion of wood. Compost of wood was implemented in two consecutive trials. The first was carried out in greenhouse experiment in 4 liter pot of Quercus rubra and Pinus sylvestris (QR and PS) moisted by compost and tap water and infected by tiger worm (Eisenia fetida, EF) and European night crawlers (Dendrobaena veneta, DV) at different mixed ratios with lake mud (LM). The second was conducted in greenhouse experiment in 40 liter pot of the successful wood and worm from the first compost trial (QR and EF respectively). The tested wood (QR) was mixed separately by lake mud and horse manure and irrigated by compost and tap water. The final product, successful wood compost (QR) produced from the first trial (4 liter pot) was utilized in different mixed ratios with coal mine tailings (tertiary sand) in greenhouse pot trial to study his effects on improving soil physical and chemical properties and some plant growth parameters of RSM 7.2.1 grass. The wood compost produced from the second compost experiment (40 liter pot) and other artificial component named Arkadolith® were used as soil amelioration in field experiments of different selected sites with extremely unsuitable characteristics (tertiary and quaternary sand in Lusatia lignite region, Germany). The soil in each site was sowed by RSM 7.2.1 and autochthonous grasses. Also, some vermicompost samples were selected to study its thermal stability which compared with a soil sample (Niedermoorgleys) by using thermogravimetric analysis technique. Further investigation was achieved to evaluate the effect of charcoal as a source of carbon on vermicompost stability. Moreover some selected vermicompost samples were used to examine its microstructure under scanning electron microscope which compared also with the same soil used in thermal analysis. The obtained results under all studied experiments can be arranged as follow: First compost trial, Cumulative amount of carbon dioxide produced during composting period was lower than that evolved by combustion of wood. The results showed composting of wood can reduce the emitted CO2 up to 50 % when compared with the amount of CO2 produced from combustion of wood. The effect of different studied factors on different studied parameters show that, QR wood compost have more responsive to decomposition processes and humification rate in comparison with PS wood compost. Under different infection worms, Eisenia fetida (EF) was better than Dendrobaena veneta (DV) in biodegradation rate. Compost water has had a better impact of tap water in all studied decomposition parameters. For example, The compost content of OM and total OC was decreased with the increase of the decomposition period in the treatments of compost water and EF worm, where this decrease was higher at mixed ratio of 1:3 (wood: mud, w/w). The total content of N in the final products takes reversible trend regarding to OM and C content. The high content of N was found in QR wood compost moisted by compost water and infected by EF worm. The content of both macro-and micro-nutrients was clearly positive affected by the studied factors. The content of these nutrients in QR wood compost was higher than that found in the compost of PS wood. Second compost trial, The observed data show that, the amount of CO2 produced by composting was lower than that evolved by combustion of wood. Composting of wood reduced CO2 emission up to 40 % of the combustion wood CO2. Cumulative amount of CO2 produced from wood compost treated by horse manure was higher than that fount in the other treated by LM. The compost of wood treated by horse manure has had a high decomposition rate in comparison with that treated by lake mud. The treatments left without worms during all composting period and moisted by compost water have a responsive effects but it was lower than that infected by worms. Total and available contents of N, P, K, Mg, Zn, and Cu in the compost treated by HM were higher than that found in compost treated by LM. The other nutrients (Ca, Fe, Cu, and Mn) take reversible trend, which it was higher in LM than HM treatments. Thermal and microstructure analysis, The selected vermicompost samples from both first and second compost experiments showed, up to 200° C temperature the mass loss was due to free water and bound water (It was in vermicompost samples higher than soil sample). Mass loss from 200 to 550° C is due to easily oxidizable organic forms and it was higher in vermicompost than soil. In this stage the soil OM seems to be more stable than vermicompost which can be explained by a more intensive bond between the organic and inorganic components. At higher temperatures (T> 550° C) no significant detectable was appeared of soil organic matter. In contrast, the vermicompost treatments showed a high proportion of stable groups, especially aromatic compounds. These statements seem to be importance particularly for the practical application of the wood compost in terms of their long-term effect in the soil. The application of charcoal, showed no additional stabilizing effect of vermicompost. Also, the data show that, vermicompost structure characterized with high homogeneity and ratio of surface area to volume compared to those in soil structure. First plant trials (greenhouse), Different compost mixed ratios had positive impact on different extreme soil physiochemical properties. At the end of experiment (42 days) compost increased soil water holding capacity, decreased soil bulk and particle density and increased total porosity. The used wood compost modified soil buffering capacity and soil acidity. The availability of soil macro and micro nutrients were increased after adding wood compost. The wood compost had a positive effect in some growth parameters like fresh and dry matter yield of the selected grass. High dry matter yield and nutrients uptake was achieved with higher rates of compost application (25.0% > 12.5% > 3.0% > 0.0 %, w/w). Second plant trials (field experiment), Regarding to the effect of wood compost (QR) and Arkadolith® component on tertiary and quaternary sand, at the end of grown season (6 month) most soil and plant characteristics of tertiary sand were improved and it was better than that in quaternary sand. This trend reveals to, physical and chemical properties of tertiary sand was better than that in quaternary sand, like organic matter content, CEC, WHC, TOC, available nutrients. In the both sites, the effects of different type of soil conditioners arranged as follow: the treatments treated with wood compost is the better followed by the other treated with both wood compost and Arkadolith. Wood compost increased soil pH, CEC, soil buffering capacity, OM content, and soil WHC in comparison with Arkadolith which make a small improvement of these properties in both sites. Finally, Different growth parameters (height, covering, fresh and dry matter yield) of the used grasses were clearly positive affected by wood compost, with the highest production inherent to the treatments treated by the high amount of wood compost. / Entsprechend der Zielstellung wurden zunächst verschiedene Varianten der Kompostierung von Holzsubstanz getestet, um eine optimale Technologie, die auch für Entwicklungsländer realisierbar ist, herauszufinden. Hierzu sind in Pflanztöpfe Holzspäne (Woodchips) von zwei verschieden Holzarten (Laub- und Nadelholz) gefüllt und mit verschiedenen natürlichen Stickstoffquellen gemischt worden. Diese Ansätze wurden regelmäßig mit Kompostwasser appliziert. Nach vier Wochen sind zwei verschiedene Wurmarten (Dendrobaena veneta und Eisenia fetida) hinzugegeben worden. Die Feuchthaltung erfolgte ab diesem Zeitpunkt durch Frischwasser. Die qualitativ beste Versuchsvariante ist im nächsten Schritt mit weiteren natürlichen Stickstoffquellen, die in Entwicklungsländern zur Verfügung gestellt werden könnten, getestet worden. Von allen Kompostvarianten sind im Labor eine Vielzahl von bodenphysikalischen (z.B. Dichte, Wasserhaltekapazität) und bodenchemischen Zustandsgrößen (z.B. Elektrische Leitfähigkeit, Totalgehalte biophiler Elemente, Bodenreaktion, organische Substanzgehalte, Kationenaustauschkapazität) bestimmt worden. Die Wiederum qualitativ beste Mischung ist in einer weiteren Versuchsreihe in verschiedenen Mengenverhältnissen mit tertiärerem Abraumsand des Braunkohlebergbaus gemischt worden. In diese Versuchsmischungen wurde die Grasmischung RSM 7.2.1 eingesät und regelmäßig bewässert sowie die Wuchshöhe gemessen. Nach 42 Tagen wurden das Gras geerntet und die biometrischen Parameter, die Nährstoffgehalte (pflanzenverfügbare Fraktionen), die Bodenreaktion, die effektive bzw. potentielle Kationenaustauschkapazität sowie die Pufferkapazitäten der Mischsubstrate bestimmt. Die nächsten Versuchsvarianten sind als Feldversuche in der Niederlausitz durchgeführt worden. Für ihre Realisierung wurde als weiterer Zuschlagsstoff Arkadolith® zugemischt. Die Plotflächen sind sowohl auf Abraumsanden des Tertiärs als auch Quartärs angelegt worden. In jeweils eine Subvariante ist RSM 7.2.1, in die andere eine autochthone Grasmischung eingesät worden. Diese Experimente wurden nach 6 Monaten beendet, die Bestimmung aller Parameter erfolgte in gleicher Weise wie bei den Gewächshausversuchen. Auf Basis aller Versuchsreihen konnten die besten Kompostqualitäten und ihre optimalen Herstellungsvarianten ermittelt werden. Eine weitere Aufgabe war es zu untersuchen, wie im Vergleich zur Verbrennung von Holzmasse die CO2-Emission in die Atmosphäre durch Holzkompostierung verringert werden kann. Hierzu wurde während der verschiedenen Kompostierungsvarianten die CO2-Freisetzung gemessen. Im Vergleich dazu ist jeweils die gleiche Masse an Holzsubstanz verbrannt worden. Die Ergebnisse zeigten, dass im Vergleich zu der thermischen Verwertung von Holsubstanz die CO2-Emission bis zu 50 % verringert werden kann. Dem Boden kann darüber hinaus energiereiche organische Substanz zugeführt werden, die eine Entwicklung der Bodenorganismen ermöglicht. Ein weiteres Experiment zielte darauf ab, die Stabilität der Holzkomposte zu bestimmen. Darüber hinaus sollte untersucht werden, ob durch die Zufuhr von pyrogenem Kohlenstoff eine Vergrößerung der Stabilität zu erreichen ist. Diese Untersuchungen wurden mit Hilfe der Thermogravimetrie vorgenommen. Alle wichtigen Kompostierungsvarianten sind sowohl mit verschiedenen Zusatzmengen als auch ohne Zusatz von pyrogenem Kohlenstoff vermessen worden. Als Vergleichssubstanz diente der Oberboden eines Niedermoorgleys, der naturgemäß einen relativ hohen Anteil an organischer Substanz aufweist. Die Ergebnisse zeigten, dass im Bereich niedriger Temperaturen die Wasserbindung im Naturboden fester ist. In der Fraktion der oxidierbaren organischen Substanz, im mittleren Temperaturbereich gemessen, ist die natürliche Bodensubstanz ebenfalls stabiler, was auf eine intensivere Bindung zwischen den organischen und anorganischen Bestandteilen, also auf stabilere organisch-mineralische Komplexe, schlussfolgern lässt. Im Bereich höherer Temperaturen (T> 550° C) waren im Naturboden keine nennenswerten organischen Bestandteile mehr nachweisbar. Hingegen wiesen die Kompostvarianten einen hohen Anteil stabiler Fraktionen, vor allem aromatische Verbindungen, auf. Diese Aussagen erscheinen vor allem für die praktische Anwendung der Holzkomposte in Hinblick auf ihre Langzeitwirkung bedeutsam. Der Zusatz von pyrogenem Kohlenstoff zeigte keine zusätzliche Stabilisierungswirkung.

A series of pot trials were undertaken to test the growth of indigenous grasses (Themeda triandra and Cynodon dactylon) on mine capping soil, treated with various soil ameliorants. The capping soils were obtained from open cast coal mines (Optimum Mine and Syferfontein Mine) in the Mpumalanga Highveld, south of Witbank. However, because mine soil was not available at the commencement of the project, the initial pot trial used soil from the Umlazi Landfill in Durban. The trials were the Umlazi Landfill Trial, Microbe Trial, Legume Trial and Fly Ash Trial. For the Umlazi Landfill Trial, landfill top and subsoil was used along with fertilizer, sewage sludge, K-humate, lime and microbes. The soil ameliorant treatments for the Microbe trial were Trichoderma harzianum (Eco'T), Bacillus subtilis Strain 69 (B69) and Bacillus subtilis Strain 77 (B77), for the Legume Trial, Medicago sativa, phosphorus and/or potassium were applied. For the Fly Ash Trial, lime and fly ash were introduced. From the Landfill trial it was shown that fertilizer and sewage sludge significantly increased the above ground, below ground and total biomass of T. triandra, further, there were no significant treatment differences between fertilizer and sludge. The lime treatment for this trial, surprisingly, significantly reduced below ground biomass but the application of microbes (B69 and BcoT) alleviated this negative effect. However, in the Microbe Trial the microbes (BcoT, B69 and B77) had a negative or no effect on the biomass of T. triandra and C. dactylon. In the Legume Trial it was shown that the above ground biomass of T. triandra was significantly reduced when grown with M. sativa. The Fly Ash Trial revealed that the lime and fly ash treatments had no effect on the biomass of M. sativa and T. triandra, and they did not maintain a reduction in soil acidity. The results therefore indicated that either organic fertilizer or sewage sludge could be used to significantly improve the growth of T. triandra. It was also suggested that lime not be applied to soils with an acid saturation of approximately 1%, as this could retard plant growth. The application of microbes and the growth of a legume with grass, although both have been recorded to have beneficial effects in aiding plant growth, in the short-term however, the application of T. harzianum, B. subtilis Strain 69 and 77 applied to the soil while growing T.triandra and C. dactylon and the growth of M. sativa with T. triandra is not recommended. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

The environmental impact and sustainability of irrigation with coal-mine water was investigated from an agricultural point of view on different coal-mines in the Republic of South Africa. Field trials were carried out on a commercial and plot scale, on sites that could offer a range of soil, crop, weather conditions and water qualities such as gypsiferous, sodium sulphate and sodium bicarbonate waters. Crop production under irrigation with gypsiferous mine water is feasible on a field scale and sustainable if properly managed. No symptoms of foliar injury due to centre pivot sprinkler irrigation with gypsiferous water were observed. The presence of high Ca and Mg in the water suppressed plant uptake of K. This could be corrected by regular application of K containing fertilizers. The bigger problem experienced was waterlogging due to poor site selection, especially during the summer months. The problem is not related to the chemistry of the gypsiferous water used for irrigation. Pasture production with Na2SO4 rich mine effluent was also feasible, at least in the short term, but would need a well-drained profile and large leaching fraction to prevent salt build up. Forage quality was not affected by the Na2SO4 water used. NaHCO3 water was of very poor quality for irrigation and is not recommended for irrigation. Salt tolerant crops that are not susceptible to leaf scorching can be produced with this water, but only with very high leaching fractions and careful crop management. Regular gypsum application will be required to prevent structural collapse of the soil. Most of the salts applied will leach from the soil profile, and will probably need to be intercepted for treatment or reuse. The Soil Water Balance (SWB) model was validated successfully. The model predicted crop growth, soil water deficit to field capacity and soil chemistry reasonably well, with simulated results quite close to measured values. Soluble salts have to be leached from the soil profile, so that crop production can be sustainable, but will externalize the problem to the receiving water environment. To assess the environmental impact of irrigation with coal-mine water, it is valuable to develop a tool that can assist with prediction of offsite effects. SWB was validated for runoff quantity and quality estimations, and was found to give reasonable estimates of runoff quantity and quality. SWB also predicted the soil water and salt balance reasonably well. This gives one confidence in the ability of the model to simulate the soil water and salt balance for long-term scenarios and link the output of SWB to ground and surface water models to predict the wider impact of large scale irrigation. This will also link the findings of this work to other research oriented towards the management of mine water and salt balances on a catchment scale. It will also help authorities make informed decisions about the desirability and consequences of permitting mine water irrigation on a large scale. Irrigation with gypsiferous mine water can be part of finding the solution to surplus mine water problems. Appropriate irrigation management of mine water is essential for the long-term sustainability of irrigation. / Thesis (PhD)--University of Pretoria, 2009. / Plant Production and Soil Science / unrestricted