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By K. M. Atencio, T. Pike, S. Forrest

We will introduce the Small Business Liability Relief and Brownfields Revitalization Act, which is an amendment to CERCLA and the types of sites it includes and excludes, especially as related to mine-scarred land. We will also describe the types of available funds, whether they are competitive or not, what entities are eligible to receive them, and how to access them. We will introduce the legislation’s liability provisions; for example, the recently issued interim guidance clarifying some of the conditions that contiguous property owners, bona fide prospective purchasers, or innocent landowners must meet to qualify for the liability limitations provided in the Brownfields Law.

Jan 1, 2004

By Chris Joyce, Peter Ryan

Investigation of the occurrence and significance of acid drainage from mine sites in Australia has received a degree of attention in recent years. For contemporary and future projects, particularly those in hi1;1her rainfall areas, the focus on prediction and resolution of acid drainage issues is. likely to increase. This paper describes the preventative and remedial measures adopted at three metalliferous mines in northern Australia at which acid drainage was identified as a key issue with respect to project environmental management and rehabilitation. The thre case studies respectively comprise an active, ·1 recently decommissioned and an abandoned operatiou which was rehabilitated in the mid '80s.

Jan 1, 1991

By Jasna Jurjovec, David W. Blowes, Carol J. Ptacek

At the Kidd Creek site, natrojarosite residue, derived from the zinc refinery circuit, is mixed with mill tailings before final disposal in the tailings impoundment. Column experiments were conducted with fresh unoxidized mill tailings and a mixture of tailings containing the natrojarosite residue. Acidic water, simulating mine drainage water, was pumped through the columns. The effluent water geochemistry was interpreted with the assistance of MINTEQA2. The experimental results suggest that the effluent water pH was buffered by a series of acid neutralization reactions. The release of metals, including Cu, Pb and Zn, was affected by pore water pH, Eh and mineralogy of the tailings material.

Jan 1, 2000

By R. S. Conti

The US Bureau of Mines (USBM) has developed an inflatable feed-tube seal (IFTS) for high-expansion foam generators. The IFTS is a lightweight, portable, rectangular inflatable bag that can be used by firefighters to rapidly seal large openings, such as those in underground mines, and to simultaneously provide a feed-tube for a high-expansion foam generator. Thus allows fire fighting foam to freely flow to the fire site and control or extinguish the fire. Studies indicated that a high-expansion foam plug will travel 183 m (600 ft) down an entry with a 4.5% rise in elevation, before leakage of foam from around the inflatable partition.

Jan 1, 1996

By V. E. Ross

A model has been developed that describes the behavior of mineral particles and water in the cleaning zone of flotation columns. The possible detachment of particles from their sites of attachment at the bubble surfaces is related to the flux of bubble surface area with increasing distance from the interface between the collection and cleaning zones and the late at which floated particles are transported into the cleaning zone. The drainage velocities of floated and entrained particles are calculated from the drainage velocity of water and the properties of the particles. The effects of wash water and inhibited drainage in the froth are also explicitly accounted for.

Jan 1, 1988

By Cindi Byrns, Andy Davis, Amy Tisdale

The Robinson district, Ely, Nevada is a hydrogeologically complex system with several distinguishable geologic blocks, each with a distinct background groundwater chemistry. To discriminate between background and mine-impacted groundwater, background wells, monitoring wells, pit lakes, waste rock seeps, and surface water samples were analyzed for a suite of major cations and anions, together with trace and precious metals, rare earth elements, 2H-deuterium and 18O/16O. The data allowed identification of groundwater flow paths, verification of hydrochemical source areas and characterization of natural attenuation mechanisms (e.g., mixing, dilution and mineral precipitation) that control the concentration and migration of metals at the site.

Jan 1, 2000

By Ralph P. Hackl

The Congress gold property, located near Goldbridge, B.C., is extremely refractory with most of the gold disseminated in fine- grained arsenopyrite. Metallurgical testwork conducted by Giant Bay Biotech Inc. indicated that biooxidation pretreatment was capable of increasing cyanide gold recovery from the ore to greater than 90%. To determine if the bioleach process could be successfully scaled up, a 225 cubic meter commercial size bioleach reactor was built and tested at the mine site in 1989. At that time the tank was the largest bioleach reactor ever operated. This paper discusses our experiences in operating the tank, summarizes some of the data obtained and describes the problems encountered.

Jan 1, 1990

By Christopher Newman, David Newman

The ability to assess, address, and predict mining-induced stress distribution is paramount in maintaining a safe and efficient underground operation as coal mines continue to develop at deeper depths and in more geologically complex reserves. This is especially true for longwall mining operations given their limited flexibility in panel layout and orientation. This paper focuses on ground behaviors and conditions observed at two deep-cover, steeply dipping longwall mining operations in Utah’s Unita coal basin. This region is susceptible to coal pillar bump/bounce events as a result of high depth of cover, high-extraction mining, and the close proximity of a thick massive stiff sandstone stratum to active mineworks. The successful prediction of mining-induced coal bump events for Mine A and Mine B operating in the Unita basin has prompted mine management to develop a rock mechanics testing database for reserve calculations. The database is applicable to mine planning as well as the development of multiple numerical models to proactively identify and address adverse ground conditions using input parameters calibrated to site-specific behaviors and conditions. For both Mine A and Mine B, the most critical question relates to longwall development and recovery for “extreme” deep-cover longwall panels at overburden depths greater than 600 m. This paper highlights the impact of high-stress concentrations associated with deep-cover longwall mining as well as the methods applied to mitigate stress impacts on miner safety and longwall production.

Jul 1, 2023

By Yi Luo

Longwall coal mines are frequently located in steep mountainous areas with narrow valleys. In order to protect surrounding watersheds and residential structures, support areas are left under the valleys. However, the indirect subsidence effects to the residential structures due to the potential topography effects can be a serious problem. The present study examines a longwall mine in southern West Virginia located in an area with an average slope of about 30°, or 58%, and with an overburden depth that varies from 49 to 376 m (160 to 1,235 ft). A comprehensive investigation was carried out to assess the subsidence and topography effects, as well as other ground control issues at this site. Surface and subsurface movements and deformation were predicted and their direct effects on nearby streams and structures were assessed. The potential and indirect subsidence influences of surface topography effects were assessed. The techniques and results of this investigation are presented in this paper. It shows that the direct and indirect subsidence effects on the streams and residential structures should be insignificant. The post-mining observations agreed well with this study.

Jan 1, 2010

By K. H. McDaniel

An interactive mine ventilation simulation software program (WIPPVENT) was developed at the Waste Isolation Pilot Plant (WIPP). The WIPP is a U.S. Department of Energy (DOE) research and development project located near Carlsbad, New Mexico. The facility is designed to provide a permanent, safe underground disposal of U.S. defense generated transuranic waste in bedded salt. In addition to its regular functions, the underground ventilation system is engineered to prevent the uncontrolled spread of radioactive materials in the unlikely event of a release. To enhance the operability system, Westinghouse Electric Corporation has developed an interactive mine ventilation simulation software program (WIPPVENT). While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC (copyright © 1991 Mine Ventilation Services, Inc.), the user interface has been completely rewritten as a Windows ® application and screen graphics have been added. WIPPVENT is designed to interact with the WIPP ventilation monitoring systems through the site wide Central Monitoring System.

Jan 1, 1996

By D. Puckett

The feasibility of maintaining equipment location, personnel location and vital statistics in surface and underground mining operations has increased with advances in radio frequency identification (RFID) technology. The paper addresses the use of this technology, relatively new in the mining industry, to track surface equipment in mine pits, loading points, and processing facilities. Specific applications are discussed including a simplified and a complex truck tracking system and an automatic pit ticket system. The paper concludes with a discussion of the future possibilities of RFID technology in mining, such as monitoring biofeedback of personnel (heart and respiration rate, body temperature, exertion level, etc.) repetitious movements to study work habits, and logging air quality via personnel sensors.

Jan 1, 1996

By K. Perry, R. Eades

"Highwall miners continue to be implemented by operations to increase recovery, improve margins, and justify higher stripping ratios as high quality surface reserves become increasingly rare. Many times, operations facilitate projected underground operations by leaving an intact highwall for development purposes. These facts result in larger highwalls that are left standing for increased periods of time prior to reclamation. As a consequence, worker exposure and risk is also elevated, resulting in higher potential for accidents or fatalities relating to surface highwalls. Highwall stability is a complex issue, dependent on both geologic and mining factors. Dynamic numerical modeling offers the capability to assess possible stability issues related to blasting-induced ground vibrations. Research has been conducted to evaluate the effect of highwall stability due to ground vibrations from blasting events. Additionally, the relationship of amplitude and frequency, and their impact on highwall stability is investigated. The results of this modeling indicate that amplitude has little impact on stability. However, frequency has a significant impact on highwall stability. INTRODUCTION The number of mining fatalities has declined since 2010, and 2016 is currently on pace to continue this trend (MSHA 2016). This decline can be directly correlated to the decline in surface mining activity and the overall decline of the coal industry. However, since 2002 the percentage of surface coal mine fatalities associated with highwall activities remains relatively high, constituting approximately 15% of all surface mine fatalities. 2014 was the first year with a highwall failure fatality since 2011. Most recent surface coal mining fatalities are associated with machinery and haulage. Table 1 provides a summary of the total surface coal mining fatalities, and the number of highwall failure fatalities dating back to 2010.Highwall stability is a complex issue, dependent upon geology and geologic discontinuities within the rock mass, along with highwall geometry, standing time, and applied stresses. Another possible concern that has not been previously investigated is the effect of blasting-induced stresses on highwall stability and the stability of web/barrier pillar systems as a result of ground vibrations from blasting events. Many modern surface coal mines employ numerous extraction fronts that rely on blasting for primary rock breakage. This results in highwall and highwall pillar systems experiencing blasting-induced stresses of many different types and magnitudes."

Jan 1, 2017

By James S. Goff, Stephen J. Navin, Wesley W. Moulton

The White River Shale Oil Corporation (WRSOC), as agent for Phillips Petroleum Company, Sohio Shale Oil Company, and Sun Shale Oil Company, is developing a prototype oil shale facility on Federal Lease Tracts Ua and Ub, located in northeastern Utah and known as the White River Shale Project (WRSP). The Ralph M. Parsons Company (Parsons) has been retained as the design engineer/constructor for the project. This paper covers the successful pregrouting of the Bird's Nest Aquifer in conjunction with the sinking of a 9.2-m (30-ft)-diameter shaft and driving of a 3.89-m by 5.64-m (18.5-ft by 12.75-ft) decline. The Bird's Nest Aquifer derives its name from the ellipsidal solution cavities caused by leaching of random-size nacholite nodules. The sodium bicarbonate nodules occur as persistent bands within a matrix of siltstone and marlstone. The team, made up of the owner, engineer/contractor, and subcontractor successfully grouted the shaft down to an inflow of less than 0.06 lps (1 gmp) and the decline down to less than 0.12 lps (2 gpm) by injecting a total of 213.190 kg (470,000 lb) of Celtite Terraseal, 113,400 kg (250,000 lb) of limestone dust, and 41,730 kg (92,000 lb) of cement into the formation.

Jan 1, 1985

By D. W. McGlashan

[Comideha;tion o 4 chyakd- chem and aLtuctund phopetttiu o auRdide nm&, The in~o/uncction gained h ;to be uned ;to iM;tmph& ( I! dnukey bho hen mind-aundacu , ( 2 ) modidicakio~n 06 ;the minmd n~tdacu, and (3) eac;tiom at ;the mind adac fnom ;thu e baic din oipfina, concep;tc, wLth hegattd ;to .the changen kha;t awtgacu undehgu, heac;tiom kha;t might take place, ,the geom&y 04 ;the inkmduce, ;the nkde 04 diddmenk &om and iom in ;the intmdace, and okhm phyaicd and chemicd pttopemXu od an intmdace mun;t be developed, weighed and appfied. The au/tho~ ded wah thue concep;tud connidmatiom @om which hypokhuu me n& ko denchibe khe envhomenkd-ivttadaciae hela;tiomhipa doh nevmd nddide minettah, The ch&enge and moltivation in khe hu eattch h in a henhe a deattch doh baic dad and helcctiomkipa needed doh accompfi he&.] INTRODUCTION Qualitative and quantitative explanation of particulate solid separations are unknown entities because of the lack of adequate models and mathematical relationships to explain the activity occur- ring between the solid and liquid phases. It is a transitional region in which it is difficult to ascertain the mechanisms of adsorption of ions, molecules, etc. on mineral surfaces, as well as other secondary reactions which occur in interfacial regions. Thus, in this paper the authors deal with conceptual considerations from which hypotheses are set forth to describe the environmental- interfacial relationships for sulfide minerals.

Jan 1, 1968

By R. Mensah-Biney

The kinetics of loading of gold from bromide solution onto an anion exchange resin, PAZ-4, were investigated in a batch stirred reactor. The initial loading rate was described mathematically by a first-order reaction rate equation. The effect of agitation speed, temperature, resin particle size, resin concentration, initial concentration of gold and bromine in solution on the rate was investigated. The model described fairly accurately the loading process in terms of the variables investigated. The rate constant for the initial loading ranged from 0.5 to 1.3 x10-3 sec-1 and the half-time was 9.3 to 56 minutes. The initial rate constant increased with increasing temperature with an activation energy of 15.7 kJ/mole (3.8 kcal/mole). The rate constant was directly proportional to the concentration of the resin in solution. The subsequent reduction reaction was also modeled by the first-order rate equation and the apparent rate constant was estimated to be 3.0 x 10-6 sec-1 with a half-time of about 44 hours.

Jan 1, 1994

The properties of interfacial water at hydrophilic surfaces are of great importance in many technological areas including flotation, solid-liquid separation, dispersion and emulsions, flocculation, adsorption, corrosion, and soil contamination. This paper examines the use of FTIR/internal reflection spectroscopy (FTIR/IRS) to study the spectral characteristics of interfacial water at silica surfaces. FTIR spectra were characterized by consideration of the OH stretching region (3000-3800 cm-1) associated with the vibrational spectra of interfacial water. The broad peak in this region was deconvoluted in order to isolate overlapping spectral features that describe the nature of hydrogen bonding in interfacial water. Three distinct bands were found; -3600 cm-1 (free OH), -3400 cm-1 (incomplete tetrahedral coordination), and -3240 cm-1 (complete tetrahedral coordination) and the variation of their intensities with pH was found to be significant. This spectral information helps to explain orientation and bond ordering of interfacial water molecules at hydrophilic surfaces.

Jan 1, 1998

By W. E. Cobb

Mining companies, as developers of natural resources, are being forced to deal with the potential long-term liabilities of past, present, and future mining operations. As discussed in a previous paper (Cobb, et al., 1987), these liabilities can include solid waste disposal corrective action programs (state or federal actions), Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), (Superfund) (state or federal actions), or natural resource damage claims (typically filed by state agencies and provisions specified in CERCLA). These potential liabilities are very real, and should dramatically impact the way a company views its exploration and development programs, and operating mines.

Jan 1, 1988

By D. K. Dysinger

The U.S. Bureau of Mines investigated leaching of chalcopyrite with sulfuric acid-oxygen under conditions anticipated during in situ leaching. A central composite experimental design was chosen to study oxygen pressures of 150, 300, and 450 psi, leach temperatures of 35?, 65°, and 95° C, oxygen-to-chalcopyrite mass ratios of 0.5, 1.0, and 1.5, leach times of 8, 16, and 24 hours, initial acid strengths of 0.6, 1.2, and 1.8 g H2SO4/g chalcopyrite and pyrite to chalcopyrite mass ratios of 0, 1, and 2. The leaching kinetics were consistent with the shrinking core model. A quadratic response surface model was used to determine linear and interaction effects of the design factors on rate constants from Arrhenius correlations.

Jan 1, 1993

By A. D. Wunderlich

Providing a safe & secure environment for your employees and other company assets is absolutely necessary in our litigeous society. Security hardware is no different than computers or other technical equipment, in that new equipment is developed each year that makes older equipment obsolete. This presentation will help to explain how your existing security system and security procedures can be updated to meet industry standards without the expenditure of a great deal of money. If you are concerned about potential security problems and how to address these problems, this presentation is a must.

Jan 1, 1995

By M. S. Prasad

In earlier work it has been shown that paper filler clay products can be obtained from primary kaolin deposits of Minnesota. The objective of the current work was to reduce silica and iron contaminants and to maximize kaolin recovery to higher value products suitable for paper coating. This results in achieving a finer and cleaner product conforming to paper coating specifications. Cationic flotation and high gradient magnetic separation were used to remove free silica and iron, respectively, while attrition grinding and ultrasonics have been examined for particle size reduction. The results of this work are presented and discussed particularly with respect to application-oriented product properties. Budgetary estimates are presented for a 200,000 ton/year processing plant based on the process flowsheet developed and optimized by the study.

Jan 1, 1991