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Graduate Theses, Dissertations, and Problem Reports

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Selective Recovery Of Rare Earth Elements From Acid Mine Drainage Treatment Byproduct, Zeynep Cicek Jan 2023

Selective Recovery Of Rare Earth Elements From Acid Mine Drainage Treatment Byproduct, Zeynep Cicek

Graduate Theses, Dissertations, and Problem Reports

Rare earth elements (REEs) are critical in emerging clean energy, advanced technologies, and military defense applications due to their unique physical, chemical, optical, and luminescent properties. Given the potential supply chain restrictions imposed by one country's dominance in the global REE market and the consistently growing demand for REEs, developing the US domestic REE supply chain is imperative. Thus, alternative sources are crucial to supply the demand and prevent interruption in manufacturing products that consume REEs. Concurrently, acid mine drainage (AMD) is a long-standing and widespread global challenge the mining industry encounters. AMD is generated in large volumes and continuously …


Analysis Of The Root Causes Of Fatal Injuries In The United States Surface Mines Between 2008 And 2021., Maria Fernanda Quintero Jan 2023

Analysis Of The Root Causes Of Fatal Injuries In The United States Surface Mines Between 2008 And 2021., Maria Fernanda Quintero

Graduate Theses, Dissertations, and Problem Reports

Mining has long been recognized as a hazardous industry worldwide. An annual average rate of 10.3 fatal injuries per 100,000 workers was recorded in the United States between 2008 and 2021 (MSHA, 2022). This rate can be compared with the average of the industries with the highest average rates of fatal injuries—agriculture, forestry, fishing, and hunting; transportation and warehousing; and construction—which had average rates of 23.5, 13.1, and 9.9 fatal injuries per 100,000 workers, respectively, during the same period in the Unites States (U.S. Bureau of Labor Statistics, 2023).

The scope of this research is related to the fatal injuries …


Augmented Reality And Mobile Systems For Heavy Equipment Operators In Surface Mining, Juan David Valencia Quiceno Jan 2023

Augmented Reality And Mobile Systems For Heavy Equipment Operators In Surface Mining, Juan David Valencia Quiceno

Graduate Theses, Dissertations, and Problem Reports

U.S. federal laws mandate that mining companies ensure a safe workplace, implement approved training programs, and promptly report work-related injuries. The mining industry's commitment to innovation reflects a history of adopting advancements to enhance environmental sustainability, workplace safety, and overall productivity, while simultaneously reducing operational costs. This thesis proposes the integration of Augmented Reality (AR) technology and digital applications to enhance the surface mining industry, presenting two innovative solutions: an AR Training System and an Operational Digital System. These business solutions have been developed and applied at a surface mine in the southwest of the US, having the potential to …


Development Of A Hydrometallurgical Process For The Extraction Of Cobalt, Manganese, And Nickel From Acid Mine Drainage Treatment Byproduct, Alejandro Agudelo Mira Jan 2023

Development Of A Hydrometallurgical Process For The Extraction Of Cobalt, Manganese, And Nickel From Acid Mine Drainage Treatment Byproduct, Alejandro Agudelo Mira

Graduate Theses, Dissertations, and Problem Reports

Critical minerals (CMs) are defined as crucial elements for the country's economy due to the development of new cutting-edge applications and the risk of an eventual disruption in their supply chain. The unique chemical and physical properties of the CMs have made these elements decisive in the growth of industries such as telecommunications, army, medicine, Aerospace, etc. In 2022, the US Geological Survey established a list of 50 CMs, including manganese, cobalt, nickel, aluminum, magnesium, and others. Of the total of CMs, 26 are 100% imported from outside the United States (Venditti, 2022).

Driven by the ever-increasing demand for critical …


Development Of An Entry-Scale Modeling Methodology To Provide Ground Reaction Curves For Longwall Gateroad Support Evaluation, Haochen Zhao Jan 2022

Development Of An Entry-Scale Modeling Methodology To Provide Ground Reaction Curves For Longwall Gateroad Support Evaluation, Haochen Zhao

Graduate Theses, Dissertations, and Problem Reports

Longwall gateroad entries are generally subjected to severe mining-induced stress changes and deformations; they are prone to large roof falls, floor heaves, and rib sloughing. The standing support system in underground mines needs to be carefully designed to compensate for the mining-induced deformation of the surrounding rock mass and consecutively protect the integrity of gateroad entries. Local geology, together with mining-induced stress redistribution, influences the ground response and plays a major role in the performance of a standing support design. In the US, Support Technology Optimization Program (STOP) and its Ground Reaction Curve (GRC) design criteria have been applied to …


Integrated Large Discontinuity Factor, Lamodel And Stability Mapping Approach For Stone Mine Pillar Stability, Mustafa Baris Ates Jan 2022

Integrated Large Discontinuity Factor, Lamodel And Stability Mapping Approach For Stone Mine Pillar Stability, Mustafa Baris Ates

Graduate Theses, Dissertations, and Problem Reports

The objective of this research is to develop a software tool that integrates the large discontinuity factor (LDF) and the Boundary Element Method software (BEM), LaModel, to allow stone mine operators to assess the impact of the large discontinuities on local pillar stability. National Institute for Occupational Safety and Health (NIOSH) published design guidelines for underground stone mines to guide the industry in designing pillar and roof support. These guidelines emphasize the impact of large, angular discontinuities on pillar strength. Esterhuizen et al. (2011) derived the large discontinuity factor (LDF) to account for the impact of discontinuities on pillar stability …


Noise Exposure Trends Among Violating Coal Mines, 2000 To 2021, Hanna Grace Davis Jan 2022

Noise Exposure Trends Among Violating Coal Mines, 2000 To 2021, Hanna Grace Davis

Graduate Theses, Dissertations, and Problem Reports

Noise-induced hearing loss has continued to be a significant issue within the mining industry, even after the passing of the MSHA’s improved noise standard in 2000. NIOSH has recognized that the noise standard enacted by both MSHA and OSHA does not properly protect workers with the 5 dBA exchange rate (i.e., the increase in noise level leading to a doubling of energy) and the lack of emphasizing the use of engineering controls over administrative controls and overreliance on hearing protection device usage. The primary objective of this study is to investigate statistical sound relationships between MSHA noise-related violations and samples …


Size Effect And Anisotropy On The Strength Of Shale Under Compressive Stress Conditions, Yun Zhao Jan 2022

Size Effect And Anisotropy On The Strength Of Shale Under Compressive Stress Conditions, Yun Zhao

Graduate Theses, Dissertations, and Problem Reports

The underground coal mines in the Appalachian region report the highest rate of roof falls in the United States. The immediate roof of these mines is mostly composed of shale. The in-situ strength of shale is necessary for designing roof support to prevent roof falls. Estimating the in-situ strength of shale requires the knowledge of both size effect and anisotropy. This research used literature review, theoretical analysis, numerical modeling, and laboratory experiment to systematically investigate the size effect and anisotropy of shale strength under compressive strength conditions.

Literature review involved a comprehensive summary of previous research on the size effect …


Investigation Of Geomechanical Behavior Of Laminated Rock Mass Through Experimental And Numerical Approach, Qingwen Shi Jan 2022

Investigation Of Geomechanical Behavior Of Laminated Rock Mass Through Experimental And Numerical Approach, Qingwen Shi

Graduate Theses, Dissertations, and Problem Reports

Roof failure in the Appalachian underground coal fields occurs often in laminated shale. Laminated shale roof in coal mines fails in unique ways, such as cutter failure or delamination failure. Extensive studies have investigated the influential factors that cause laminated roof failure, which include in-situ stress, entry layout, roof span, and roof support. However, cutter failure continues to occur frequently and erratically. This is due to the lack of in-depth understanding of the inherent properties of the laminations, such as bedding plane strength, matrix strength, and bedding plane spacing, which in turn influence the geomechanical behavior of the laminated rock. …


Calcite Depression In Bastnaesite-Calcite Flotation System Using Organic Acids, Emmy Muhoza Jan 2022

Calcite Depression In Bastnaesite-Calcite Flotation System Using Organic Acids, Emmy Muhoza

Graduate Theses, Dissertations, and Problem Reports

Bastnaesite is the primary source of light REEs, namely cerium (Ce), lanthanum (La), praseodymium (Pr), neodymium (Nd), to name a few. Bastnaesite is typically concentrated using the froth flotation beneficiation method. Flotation of bastnaesite suffers from high reagent consumption due to the similar surface characteristics of bastnaesite and associated gangue minerals, including calcite. Additionally, complex stages of high-temperature conditioning are often required to suppress the detrimental impact of dissolved calcium ions on the flotation of bastnaesite. This research seeks to investigate the capabilities of organic acids in the bastnaesite-calcite flotation systems to selectively depress calcite minerals and effectively chelate calcium …


Experimental And Theoretical Investigation On The Initiation Mechanism Of Low-Rank Coal's Self-Heating Process, Yinan Zhang Jan 2022

Experimental And Theoretical Investigation On The Initiation Mechanism Of Low-Rank Coal's Self-Heating Process, Yinan Zhang

Graduate Theses, Dissertations, and Problem Reports

Coal spontaneous combustion remains a safety concern during coal mining, transportation, and storage and requires further investigation to develop effective prevention and control strategies. While various intrinsic and extrinsic conditions may influence coal self-heating, low-rank coals are more prone to spontaneous combustion, especially in humid climates. Therefore, quantifying the effect of extrinsic moisture on the self-heating of low-rank coals is critical for understanding the high propensity of low-rank coals for spontaneous combustion. Many studies have qualitatively evaluated the role of extrinsic moisture on the coal self-heating. Despite this, few studies have quantified the contribution of extrinsic moisture on wetting and …


Static Liquefaction In Tailing Dams, Jose Raul Zela Concha Jan 2022

Static Liquefaction In Tailing Dams, Jose Raul Zela Concha

Graduate Theses, Dissertations, and Problem Reports

The Fundao tailing dam in Brazil failed on November 5, 2015 causing loss in life, property and severe damage to the environment. The waste flow traveled at 11m/s and approximately 32 million m3 tailings was released into the downstream area. Investigations by regulators concluded that a series of poor designs and construction of the tailing were the causes of the failure. Further investigations also showed that surface failure occurred in the mid height of the slope with a safety factor of 0.52. Both investigations concluded that static liquefaction induced the failure of tailings dam. However, geology variation in the …


Evaluation Of Lidar Systems For Rock Mass Discontinuity Identification In Underground Stone Mines From 3d Point Cloud Data, Mario Alejandro Bendezu De La Cruz Jan 2021

Evaluation Of Lidar Systems For Rock Mass Discontinuity Identification In Underground Stone Mines From 3d Point Cloud Data, Mario Alejandro Bendezu De La Cruz

Graduate Theses, Dissertations, and Problem Reports

The goal of this thesis is to compare the accuracy and precision of the discontinuity identification results obtained by three active remote sensing technologies along with a point cloud processing program, and the results obtained by conventional methods. For this research, the active remote sensing devices were terrestrial LIDAR, mobile LiDAR with Simultaneous localization, and mapping (SLAM), and LIDAR/Camera on an autonomous UAV. The open-source point cloud data processing programs Discontinuity Set Extractor (DSE) and the Cloud Compare were used to process point cloud data.

The results of this research found that it is possible to identify certain geological structures …


Optimization Of Operating Conditions And Design Parameters On Coal Ultra-Fine Grinding Through Kinetic Stirred Mill Tests And Numerical Modeling, Francisco Patino Jan 2021

Optimization Of Operating Conditions And Design Parameters On Coal Ultra-Fine Grinding Through Kinetic Stirred Mill Tests And Numerical Modeling, Francisco Patino

Graduate Theses, Dissertations, and Problem Reports

This study investigated the ultra-fine coal grinding performance of four low- to moderate-cost grinding media: ceramic balls, granular sand, alumina beads, and silica beads. The kinetic grinding tests were conducted using a stirred mill, while different operating conditions, including the media size, solids concentration, and the addition of viscosity modifiers, were examined. Characterization studies in terms of particle size, shape, and surface morphology were further performed to support the experimental findings. Moreover, using population balance modeling, grinding simulation was performed in Matlab to forecast the particle size distribution based on the specific energy input and experimental size-related data. The results …


The Effect Of Natural Fractures On The Mechanical Behavior Of Limestone Pillars: A Synthetic Rock Mass Approach Application, Mustafa Can Süner Jan 2021

The Effect Of Natural Fractures On The Mechanical Behavior Of Limestone Pillars: A Synthetic Rock Mass Approach Application, Mustafa Can Süner

Graduate Theses, Dissertations, and Problem Reports

In general, underground limestone mines have inherently strong rock and experience good ground stability. Also, modern pillar design guidelines developed by National Institute for Occupational Safety and Health (NIOSH) have improved the design of stable layouts for modern limestone mines. However, ground control-related incidents are still an important problem. In underground limestone mines, previously mined sections stay open for the life of the mine which may be many years, and it is possible for travel ways to working faces to pass through these old sections. In a recent massive pillar collapse in an old section of a mine in Pennsylvania …


Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini Jan 2021

Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini

Graduate Theses, Dissertations, and Problem Reports

Machine automation and atmospheric monitoring are used by many industries to improve safety and productivity in the workplace. The underground Methane Watchdog System (MWS) is a multi-nodal network of sensors currently under development. The MWS aims to improve safety and productivity by introducing 10 compact sampling units designed to be easily integrated within the current roof support equipment of the mine. Each unit contains an array of sensors used to continuously monitor the environmental conditions which include methane concentration, temperature, pressure, and relative humidity. All MWS units report information back to a remote central processing hub (CPH) which collects nodal …


Recovery Of Phosphorus From Florida Phosphatic Waste Clay, Amir Eskanlou Jan 2021

Recovery Of Phosphorus From Florida Phosphatic Waste Clay, Amir Eskanlou

Graduate Theses, Dissertations, and Problem Reports

This MS thesis examines the recovery of phosphorus (P) from Florida waste clay (WC). A comprehensive literature review revealed that: (i)-The most important values being lost to WC are P and rare earth elements (REEs). For the recovery of these values from WC, two crucial attempts are the removal of extremely fine-sized clays, followed by the recovery of phosphate content, which can pave the path for the recovery of REEs; (ii)-Any scientific/ technological solution should, at the same time, be economically and environmentally attractive to the industry. As such, moving from mostly chemical separation processes to the primarily physical/ physicochemical …


Geology Oriented Loading Approach For Underground Coal Mines, Deniz Tuncay Jan 2021

Geology Oriented Loading Approach For Underground Coal Mines, Deniz Tuncay

Graduate Theses, Dissertations, and Problem Reports

Mining-induced stresses in underground coal mines play a significant role in pillar and support design, hence in the safety of mining operations. Adequate design of pillars and roof control plans rely on the accurate assessment of the mining-induced loads, as well as the load-bearing capacities of the supports. In pillar design tools frequently used by the underground coal mining industry and Mine Safety and Health Administration (MSHA), overburden loading is estimated by geometric concepts such as the tributary area and the abutment angle method. These methods do not explicitly consider important mechanical responses such as specific overall ground behavior. The …


Implementing The Empirical Stone Mine Pillar Strength Equation Into The Boundary Element Method Software Lamodel, Samuel Escobar Jan 2021

Implementing The Empirical Stone Mine Pillar Strength Equation Into The Boundary Element Method Software Lamodel, Samuel Escobar

Graduate Theses, Dissertations, and Problem Reports

In this research, the equation for the increasing stress into the interior of a stone mine pillar, as a function of the pillar width-to-height ratio, is derived from the empirical pillar strength equation proposed by Esterhuizen et al. (2011). The gradient stress equations for the stone mine pillars were derived by following similar approaches to those presented by Mark et al. (1992) and Johnson et al. (2014). In these approaches, it is assumed that the variation of stresses within the pillar is a function of distance to the closest rib. The stress gradient function provides the stress distribution within the …


Various Operational Aspects Of The Extraction Of Critical Minerals From Acid Mine Drainage And Its Treatment By-Product, Zhongqing Xiao Jan 2021

Various Operational Aspects Of The Extraction Of Critical Minerals From Acid Mine Drainage And Its Treatment By-Product, Zhongqing Xiao

Graduate Theses, Dissertations, and Problem Reports

Acid mine drainage (AMD) is environmentally hazardous acidic water, which is continuously generated in large volumes at coal mining sites, typically when pyrite is exposed to oxygen and water. As its continuous migration under the geologic conditions, AMD tends to leach metal elements out from the surrounding minerals, leading to high concentrations of metal elements, like iron, aluminum, magnesium, manganese, lead, arsenic, as well as critical cobalt and rare earth elements (REEs). AMD must be treated and monitored to meet the effluent limits, under U.S.C §1251, the Clean Water act, before being discharged to receiving streams.

Recently, the research is …


Evaluation Of Various Separation Techniques For The Removal Of Actinides From A Rare Earth-Containing Solution Generated From Coarse Coal Refuse, Deniz Talan Jan 2021

Evaluation Of Various Separation Techniques For The Removal Of Actinides From A Rare Earth-Containing Solution Generated From Coarse Coal Refuse, Deniz Talan

Graduate Theses, Dissertations, and Problem Reports

Rare earth elements have emerged as a vital commodity due to their significance in the production of high-tech devices as well as their utilization in defense and military systems. They are deemed critical due to potential scarcity, supply constraints, and the lack of minable concentrations. Therefore, alternative sources are needed to meet the demand and continue manufacturing rare earth-required products. Coal and coal by-products, in that regard, have presented a significant opportunity and proven to contain a considerable amount of rare earths. However, toxic elements such as thorium and uranium are frequently seen in the same mineralization as rare earths. …


Solution Tool To Predict Filter Cake Formation For Acid Mine Drainage (Amd) Slurries, Roberto Ecuador Martinez Ochoa Jan 2020

Solution Tool To Predict Filter Cake Formation For Acid Mine Drainage (Amd) Slurries, Roberto Ecuador Martinez Ochoa

Graduate Theses, Dissertations, and Problem Reports

Acid Mine Drainage (AMD), also known as alkaline mine drainage resulted from abandoned and active coal mining areas has been a major water pollutant in the mid-Atlantic region of the United States affecting aquatic life, recreational areas, tourism, etc. AMD results from during and post mining activities all around the US and the world containing high levels of acidic materials such as sulfate and other heavy metals.

The United States Environmental Protecting Agency (EPA) has recommended the use of different mechanisms for mitigation purposes due to considerable existing and potential damage generated by AMD. This report focuses on the usage …


Fundamental Studies On The Recovery Of Rare Earth Elements From Acid Mine Drainage, Xue Huang Jan 2020

Fundamental Studies On The Recovery Of Rare Earth Elements From Acid Mine Drainage, Xue Huang

Graduate Theses, Dissertations, and Problem Reports

The Rare Earth Elements (REEs) are a group of 17 chemically similar elements that are essential raw materials for modern society. Given their increasing importance in civil and defense applications, many national governments, including the US, have denoted the REEs as critical materials and emphasized the need to identify and develop both conventional and unconventional resources to meet the growing demand. To address this challenge, the US Department of Energy has recently spearheaded efforts to evaluate the technical and economic feasibility of recovering REEs from coal and coal byproducts, which have been shown to contain REEs at an elevated concentration …


Upstream Tailings Dam - Liquefaction, Mladen Dragic Jan 2020

Upstream Tailings Dam - Liquefaction, Mladen Dragic

Graduate Theses, Dissertations, and Problem Reports

The collapse of Dam I, tailings dam, at Vale S.A.’s (“Vale”) of the Córrego do Feijão Iron Ore Mine in Brazil was an accident that caused over 270 casualties and made irreparable damage to the surrounding environment. The exact reason for the failure is not known however, liquefaction was suspected to be the most influencing factor in the failure. Liquefaction failure of impoundment is increasing concern in the mining community and especially mine planners who will have to design and build the tailings dam. Different design methods are available with varied degree of challenges. Upstream construction methods, as one of …


Development, Analysis And Case Studies Of Impact Resistant Steel Sets For Underground Roof Fall Rehabilitation, Dakota D. Faulkner Jan 2020

Development, Analysis And Case Studies Of Impact Resistant Steel Sets For Underground Roof Fall Rehabilitation, Dakota D. Faulkner

Graduate Theses, Dissertations, and Problem Reports

Underground mines often experience roof falls in entries, crosscuts, and intersections of active mining sections, main travel ways, and belt entries. Roof fall heights greater than 20 ft (6 m) make re-bolting of the newly exposed roof dangerous and impractical. To protect mine personnel, belts, moving vehicles, and other equipment, mine operators typically install steel structures such as square or arch sets in the roof fall areas. Wood lagging is usually installed between the steel-sets to enclose the area and protect the entry from recurring falls. Usually the void space above the steel-sets and wood lagging is backfilled. However, backfilling …


Solutions To Some Mine Subsidence Research Challenges, Jian Yang Jan 2020

Solutions To Some Mine Subsidence Research Challenges, Jian Yang

Graduate Theses, Dissertations, and Problem Reports

The objective of this work is to address three challenging topics, (1) effects of overburden key strata on subsurface subsidence; (2) effects of longwall subsidence on interstate highways and highway bridges; and (3) effects of dewatering mine water on surface subsidence over inactive room-and-pillar mines, in mine subsidence and to continue improvement of mine safety and health by reducing mine-subsidence related hazards.

Surface and subsurface subsidence events induced by underground mining activities are often capable of causing significant disturbances not only to surface structures, but also to subsurface structures. In this work, models and techniques to study three challenging topics …


Adaptation Of Coal Mine Floor Rating (Cmfr) To Eastern U.S. Coal Mines, Sena Cicek Jan 2020

Adaptation Of Coal Mine Floor Rating (Cmfr) To Eastern U.S. Coal Mines, Sena Cicek

Graduate Theses, Dissertations, and Problem Reports

Floor heave—the excessive deformation and failure of floor strata—is a serious problem for many underground coal mining operations in the U.S. There is an accepted floor heave design methodology developed for the Illinois basin coal mines (Gadde, 2009). However, for Eastern U.S. coal mines in the Appalachian region, there is not any systematic design method to assess floor heave potential. In order to prevent stability problems associated with floor failure and to ensure the safety of the miners in this region, a systematic and proactive method to assess the potential of floor stability that also takes the floor failure mechanisms …


Rational Drilling Control Parameters To Reduce Respirable Dust During Roof Bolting Operations, Hua Jiang Jan 2020

Rational Drilling Control Parameters To Reduce Respirable Dust During Roof Bolting Operations, Hua Jiang

Graduate Theses, Dissertations, and Problem Reports

Roof bolting has been the primary means to improve mine safety in the aspect of preventing different types of roof falls in underground mines. However, based on the published researches, underground roof bolting operators exhibit a continued risk for overexposure to high levels of respirable coal and crystalline silica dust from the roof drilling operation. Inhaling these dust can cause coal workers’ pneumoconiosis (CWP), also known as black lung. Another job-related lung disease silicosis, a disabling and even fatal and irreversible illness, could be developed through overexposure to quartz-laden dust. A recent NIOSH research shows that the quartz content in …


An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic Jan 2020

An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic

Graduate Theses, Dissertations, and Problem Reports

Improving the quality of equipment training for the Heavy Equipment Operators (HEO) is a critical task in the ever-lasting effort to improve safety and eliminate equipment-related injuries in mining environments. Traditional miner training includes the use of hardcopy documents and video instructions. However, modern mobile and computer technology offers tremendous potential to improve the training process. One major responsibility for the heavy-machine operators is proper machine inspection. Establishing new training methods that utilize modern technologies—such as 360-degree images, videos, and Virtual Reality—and implementing computers for training purposes have a potential to help new operators learn how to conduct proper machine …


The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao Jan 2020

The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao

Graduate Theses, Dissertations, and Problem Reports

The heterogeneity in the rock formation affects both rock behavior and the strength. The effect of heterogeneity is observed both at the laboratory scale and at the rockmass level. The mechanical properties of intact rock vary considerably at laboratory scale and often an average value is used for design purposes. Similarly, the values are arbitrarily scaled when used at rockmass level. In underground coal mines, the effect of variability of properties is often observed with the erratic roof failure events that occur throughout the mine. The approach often was to use the deterministic values from limited site data to estimate …