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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Open Pit Mine Planning: Analysis and system modeling of conventional and oil sands applications

Thorley, URSULA 04 October 2012 (has links)
In the last decade mineable oil sands production in Canada has grown rapidly. Constraints on the planning and design processes employed by surface mining oil sands operations vary in distinct ways from other commodities mined by both hard and soft rock open pit methods. The unique waste handling needs, including tailings disposal, of contemporary oil sands mining requires specific planning considerations. It is the purpose of this research to analyze and document a conventional hard rock, metal mine planning system, and contrast this with the unconventional mine planning system used by oil sands mines. Systems activity models of both the conventional and unconventional systems are developed in support of documenting and contrasting the two systems. Constraints unique to oil sands mine planning are identified and their impact on the oil sands mine planning system are documented. The impacts of challenging waste handling and storage requirements and a uniquely prescriptive regulatory environment defining mineable ore are identified as key constraints. The research concludes with a proposal for a new planning system to better support the planning of oil sands mines. The proposed system respects the unique waste management considerations in oil sands planning and revisits the current regulatory approach to ensuring resource recovery. The proposed system is compatible with traditional approaches to economic analysis in open pit planning, and with emerging best practices to manage technical and economic uncertainty, improve project optimization, and develop robust mine plans. / Thesis (Ph.D, Mining Engineering) -- Queen's University, 2012-10-02 17:52:18.223
2

Properties and Potentials of Coal Mine Soils in Southwest Virginia 29 Years After Establishment

Craig, Nina Genevieve 17 January 2013 (has links)
Current reclamation research following surface mining in the Appalachian coal region seeks to measure carbon (C) and nutrient accumulation and retention under forest vegetation to better understand the role of reforestation in the re-establishment of these ecosystem services. This study capitalized on the Controlled Overburden Placement Experiment (COPE), a 29-year-old reclamation research installation in southwestern Virginia, to estimate long-term mine soil C sequestration potentials and nutrient capitals after different reclamation strategies. The COPE includes two studies, a rock mix study (RM) comparing topsoil substitutes created from different ratios of local overburden [pure sandstone (SS), pure siltstone (SiS), 2:1 SS to SiS, 1:1 SS to SiS, and 1:2 SS to SiS], and a surface amendment study (SA) comparing organic amendments [control (CON), natural topsoil (TS), sawdust (SD), and 22 Mg ha-1 (22B), 56 Mg ha-1 (56B), 112 Mg ha-1 (112B) and 224 Mg ha-1 (224B) of biosolids] on a common 2:1 SS to SiS topsoil substitute. In the RM, overburden selection significantly affected soil nitrogen (N) and C concentrations as well as many other soil chemical [e.g., available phosphorus (P), pH, and other macro- and micronutrients) and physical (e.g., sand, silt and clay contents) properties.    C sequestration rates were also significantly different and ranged from 0.13 to 0.47 Mg C ha-1 yr-1. Many of the differences demonstrated relationships with the mineral make-up of the RM treatment. The SA mine soils also differed significantly in many properties after 29 years, including N, C, and many other nutrient concentrations and contents. C sequestration rates were also significantly different with the SD and 224B treatments having negative sequestration rates, and the remaining treatments ranging from 0.23 to 0.80 Mg C ha-1 yr-1. Collectively, the results demonstrate that topsoil substitutes and surface amendments show divergent trends in soil C and nutrient dynamics after nearly three decades of development and stress the importance of post- mining reclamation based on available materials and reclamation goals. / Master of Science
3

Costs of reclaiming surface mined lands : seven county area of the Ohio coal region

Flocken, Jennifer Cotterill January 1979 (has links)
No description available.
4

Site Quality Classification for Mapping Forest Productivity Potential on Mine Soils in the Appalachian Coalfield Region

Jones, Andy Thomas 11 August 2005 (has links)
Surface mining for coal in the Appalachian region destroys native forests and replaces them with reclaimed landscapes that are often revegetated as grasslands and are unacceptable for managed forest production without extensive remediation. Tree survival and growth are dependent on many reclaimed mine land properties. However, conventional mapping techniques using USDA soil series does not identify these critical soil property differences. This study was conducted to create a forest site quality classification system to be used to evaluate the potential productivity of specific tree species on mine soils. High soil bulk density is the most common limitation on mine soils and methods to efficiently measure this property were evaluated. No valid quantitative method of measuring mine soil bulk density was found due to the high rock fragment content in the soil profile, but a method for estimating relative soil density class was developed. Other soil chemical and physical properties were analyzed at abandoned mine sites in Virginia, West Virginia, and Ohio. Mine soil properties differed throughout the Appalachian region, with Ohio sites having finer textures and less rock fragments, West Virginia sites having coarser textures and a high quantity of dark-colored shale, and Virginia sites dominated by sandstone rock types. Selected field-measured soil and site properties were regressed with site index (SI) base age 50 at 52 sample locations in 10- to 18-year old white pine (Pinus strobus L.) stands on reclaimed mine lands. Sufficiency curves for nine soil and site properties were produced and a general productivity index (PI) calculated. Regression of the general PI and measured SI of white pine produced an R2 of 0.61. The general PI was simplified to four soil properties (soil density, rooting depth, texture, and pH) most significantly related to the SI of white pine, and the properties were weighted based on their importance to white pine growth on mine soils. The modified PI model produced an R2 of 0.69 for a linear relationship between PI and measured SI. The SI values were divided into five classes of equal interval and the corresponding PI values were used to define five forest site quality classes that could be identified by measuring and mapping differences in the PI on older mine soils. The model may be modified for determination of hardwood productivity after validation sites are located. Soil and site properties that are correlated with seedling survival appear different than those properties important for tree productivity. The forest site quality classification system proposed here proved practical for mapping a selected mine site, and the maps may be used as a validation test after future reforestation. / Master of Science
5

An improved model for prediction of PM10 from surface mining operations /

Reed, William Randolph. January 1900 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 2003. / Vita. Abstract. Includes bibliographical references (p. 255-263).
6

Evaluating Stream and Wetland Restoration Success on Surface Mines in Southern Illinois

Borries, Blair 01 December 2013 (has links)
Wetlands and streams provide many ecosystem services, yet many of these services have been lost during the process of surface mining. It is often not practical to avoid wetlands and streams, and newer technologies such as large draglines have made it possible to mine through large perennial streams and their associated riparian wetland systems. Laws such as the Surface Mining Control and Reclamation Act and Clean Water Act require the restoration of these systems in approximately the same location and configuration as before mining, but do not address the long-term replacement of function. In Perry County, Illinois, three stream segments of Bonnie Creek, Galum Creek, and Pipestone Creek and their associated riparian wetland systems were among the largest ever restored following surface mining. The research objective was to determine whether or not function was restored in the three aforementioned streams and riparian wetlands following surface mining reclamation. Wetland soil properties, vegetation, and hydrology at study sites along Bonnie and Galum Creeks were compared to that of nearby natural wetlands and across a chronosequence of soil age. Water quality was assessed [alkalinity, chloride (Cl), fluoride (Fl), iron (Fe), manganese (Mn), zinc (Zn), nitrate (NO3), sulfate (SO4), total dissolved solids (TDS), and total suspended solids (TSS)] in the three restored streams for post restoration trends over time and along the length of the restored channels. Deep basins, called incline pits, were located inline of all three restored channels and are unique to streams restored on surface mines. Stream samples were collected above and below incline pits during storm events to evaluate their ability to reduce sediment concentrations. Two types of wetlands were found at the mine site: mined planned wetlands (MPWs) that had deeper water and fewer or no trees, and mined bottomland forested wetlands (MBFWs) with more shallow water depths and many trees. Significant differences were found between the two wetland types among soil properties, vegetation, and hydrology. Unlike most studies comparing wetlands restored on non-mined sites to natural wetlands, SOM, C, N, and C/N ratio in the surface 15 cm in the MBFWs were not significantly different from the natural wetlands, indicating restoration of function. Plant taxa richness was higher in both mined wetland types than in the natural wetlands at lower elevation sample points where inundation was seasonal. Overall, the mined wetlands also retained water within 30 cm of the surface for more time than the natural wetlands. However, not all function was fully regained in the mined wetlands. Several soil properties were significantly different in the mined wetlands compared to the natural wetlands. SOM, N and the C/N ratio was significantly lower in the 15-30 cm depth, and in the surface 15 cm of the lower elevation samples of the MPW. Soil texture was significantly different in the MPW. There was more sand and less silt. Plan taxa richness was also lower in the higher elevation sample points of the MPW due to the presence of the invasive Phragmites australis. Few trends were found in the soil properties across a chronosequence of soil age. Only pH showed a significant negative linear trend in both mined wetland types across soil age. Assessment of the water chemistry of the restored streams showed that for some parameters, water quality remained stable or improved with distance or time along the restored streams. However, along Bonnie and Galum Creek, a significant positive trend was seen by length of relocated channel in SO4, Fe, Mn, Zn, TDS, conductivity, and Cl. On the other hand, at Pipestone Creek, significant negative trends were evident in TDS, Mn, water temperature, conductivity, and SO4 levels over time or along the length of the relocated channel. Trends along the length of the Pipestone Creek were only found in monitoring conducted twenty years after the channel relocation was complete. Sediment concentration above and below the incline pits inline of Bonnie and Galum Creek were not significantly different based on the sampling of two storm events. An additional input from an agricultural drainage ditch to the Bonnie Pit increased sediment concentrations at the downstream sample point counteracting the reductions that were seen in the Galum pit. Research on the mined stream and riparian systems indicated that reclamation of wetlands and streams to a stable or condition similar to a natural system is possible and sets a standard for future mining operations to follow. However, several shortcomings were identified. Reduced levels of SOM and soil N in the MPWs in the surface 15 cm of the lower sample points may have been the result of longer periods of inundation that reduced nitrification and vegetation recruitment. SOM, soil N, and the C/N ratio in the 15-30 cm depth were lower in the mined wetlands suggesting that these properties take longer to recover at deeper depths, but the significant linear trend in pH show that soil in the deeper strata is changing with time. Invasion by P. Australis reduced taxa richness suggesting that invasive plants are still a problem even more than twenty years after restoration. In addition, the increase in conductivity and SO4 downstream of a visible seep in Bonnie Creek highlight the potential for contaminated groundwater to affect surface water. More consideration should be given to reclaiming not just the surface and subsoils, but also the deeper water bearing strata to ensure that surface water chemistry is not impacted by mining.
7

RESTORATION OF RIPARIAN BUFFER FUNCTION IN RECLAIMED SURFACE MINE SOILS IN SOUTHERN ILLINOIS

Rahe, Nathan 01 May 2013 (has links)
Riparian buffers have been proven to reduce nutrient and sediment transport to streams in agricultural watersheds. Southern Illinois offers a unique opportunity to study functions of riparian buffers in reclaimed mine soils. In Perry County, Illinois three stream segments of Bonnie Creek, Galum Creek and Pipestone Creek were restored to their approximate original position following mining. Between 1980 and 2000, as part of the restoration, vegetative buffers of grasses and trees were planted along the streams to minimize nutrient and sediment inputs from adjacent restored agricultural land. Our research objective was to determine whether riparian soil function was being restored in the vegetated buffers by comparing multiple soil properties to the adjacent reclaimed soils in agricultural production. Four transects were established on each study site through the buffer and agricultural field. Ten one meter plots were evenly spaced along each transect in each of the land uses. In summers 2010 and 2011, water infiltration rates, bulk density, total carbon concentration, total nitrogen concentration, and C:N ratio measurements were made to assess the restoration of soil function. Soil water infiltration was significantly higher and bulk density was significantly lower in the riparian buffers compared to the adjacent agricultural fields. In the riparian buffer, roots likely helped to break up the soil adding pore space, which reduced the bulk density and increased the water infiltration rates. Soil total carbon, total nitrogen, and C:N ratio were significantly higher in the riparian buffers than the agricultural fields. The additional organic matter inputs from the roots of the riparian vegetation along with incorporation of litter from the soil macrofauna likely helped to increase the soil carbon and nitrogen levels compared to the agricultural fields. Even though the soil C:N ratio was significantly higher in the riparian buffers than the agricultural fields, more time is needed to restore the ratio to levels where nitrogen will be immobilized not mineralized in the riparian soils. Soil function in the riparian areas should continue to develop at a faster rate compared to the agricultural fields due to the impact of the perennial vegetation. Restoration of landscapes is not estimated by the return of structure alone, it also includes the re-establishment of function such as soil quality improvement, water quality improvement, and wildlife habitat restoration.
8

Assessment of Biogeochemical Maturation of Overburden Disturbed by Surface Mining

Poncelet, Dominique M. 15 August 2011 (has links)
No description available.
9

Maternal Residential Proximity to Central Appalachian Surface Mining and Adverse Birth Outcomes

Buttling, Lauren G. January 2020 (has links)
Maternal residency in Central Appalachian coalfields has been associated with low birth weight at the county-level. To refine the relationship between proximity and adverse birth outcomes, this study employs finer spatial scales of exposure. Spatiotemporal characterizations of surface mining boundaries in Central Appalachia between 1986-2015 were developed using Landsat data. The maternal address field on births records from VA, WV, KY, and TN were geocoded and assigned amount of surface mining within a 5km radius of residence (street-level). Births were also assigned exposures based on the amount of surface mining within residential ZIP code tabulation area (ZCTA) (ZIP code-level). Using linear and logistic regression, associations between surface mining activities during gestation and birth weight, preterm birth, low birth weight, and term low birth weight were determined, adjusting for available demographic factors. An increase in surface mining activities was negatively associated with birth weight at the street-level (β = −8.93g; (95% CI = -12.69 -5.7, P= <0.001) and ZIP code-level (β = −4.41g ; 95% CI = -6.30, -2.52, P= <0.001). Small, statistically significant associations were also found between preterm birth and mining within 5km of residence (OR = 1.003; 95% CI = 1.001, 1.005, P= 0.003) and within maternal ZCTA (OR = 1.002; 95% CI = 1.001, 1.003, P=0.001). Relationships were also found between amount of mining within 5km of residence and low birth weight and term low birth weight outcomes. This study found subtle, but significant associations between proximity to active surface mining during gestation and adverse birth outcomes. / M.S. / Central Appalachian surface mining produces air, water, and noise pollution, all of which have been associated with increased risk of adverse birth outcomes. Previous studies examining associations between surface mining and adverse birth outcomes rely upon relatively coarse county-level data. This research compares outcomes from hundreds of thousands of individual birth records and proximity of maternal home address to surface mines for a fine-scale, epidemiological study. Surface mining boundaries between 1986-2015 were developed using satellite imagery. Birth records from VA, WV, KY, and TN were geocoded and assigned the amount of surface mining within a 5km radius of residence. Births were also assigned exposures based on the amount of surface mining within residential ZIP code since geocoding led to a considerable loss of records. Associations between proximity to surface mining during gestation and birth weight, preterm birth (PTB), low birth weight (LBW), and term low birth weight (tLBW) were determined by linear and logistic regression, adjusting for available demographic factors. Results demonstrate significantly decreased birth weights were found near active mining operations. Mothers living near active surface mining also saw a slight increase in the odds of their birth being PTB, LBW or tLBW. These results suggest there is a subtle, but significant relationship between proximity to surface mining and adverse birth outcomes.
10

AN INVESTIGATION OF TREE GROWTH AND WOODY VEGETATION COLONIZATION ON A 19 YEAR-OLD FORESTRY RECLAMATION SITE

Dement, Wesley T. 01 January 2017 (has links)
Survival, growth and biomass accumulation of 19 year-old trees planted on an Appalachian surface mine site were evaluated to determine the effect of spoil grading and surface amendment treatments. Three spoil grading treatments (loose-dump, strike-off and graded control) were established to create a range of operationally feasible spoil compaction capable of impacting tree establishment and growth. Likewise, three surface amendment treatments (straw/manure mulch, hardwood bark mulch and control) were applied to determine their effects on tree development. Trees grown under low-compaction grading treatment levels (strike-off and loose-dump) consistently outperformed trees planted in a high-compaction control treatment. Loose-dump preparation resulted in higher survival for five of six tree species and greater biomass in three species for which this metric was estimated. Strike-off preparation resulted in higher diameter at breast height (DBH) values. The addition of straw/manure surface amendment increased biomass for hardwood species for which this value was estimated. Volunteer woody vegetation growing in the same experimental plots was measured and characterized by species. Loose-dump plots exhibited highest overall volunteer stem and native stem density and compacted control plots had lowest volunteer stem density and lowest proportion of native stems. Strike-off plots exhibited intermediate values for both of these measures.

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