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By Dan Payne

Roof falls and other ground control incidents make up a significant portion of fatal accidents in underground mines. BHP Billiton has undergone a review of all fatalities in their operations and divided these into 10 fundamental categories of which underground ground control is one. Each underground roof fall fatality was investigated and the root causes workshopped to develop a protocol for the control of fatalities due to falls of ground. This protocol sets out 22 requirements which each BHP Billiton underground mine site must comply with. This paper describes the development, requirements and application of the protocol within BHP Billiton.

Jan 1, 2006

By Stuart A. Bengson

It is extremely difficult to revegetate disturbed sites and mineral wastes in an arid environment because of sporadic and undependable rainfall. Thus, irrigation is often a must for starting seed germination and vegetation. Quite aside from the harsh climate, mining disturbances by themselves cause various adverse conditions for a revegetation program. The problems of revegetating a harsh soil, for instance, are often compounded by the steep slopes of mine wastes. Since these steep slopes intensify the droughty conditions by rapidly draining away soil moisture and accelerating runoff, supplemental irrigation may be the only solution for establishing vegetative cover on the slope.

Jan 8, 1976

By Wesley L. Bender, James E. Murray

Pre-blast surveys are often conducted solely to document existing structural conditions and uncover potential problem areas. This paper presents a case history where the pre-blast survey was also used as a vehicle to initiate a public relations program with the occupants of a large apartment complex adjacent to a major excavation site. The public relations program, in conjunction with good blasting practices, succeeded in keeping complaints to a minimum. The presentation includes an overview of the project, details of the public relations program, some of the blasting methods that were utilized and a recap of the complaints received.

Jan 1, 1988

By J S. Simmons, J G. Skousen

This project evaluated the performance of nine passive treatment methods by studying 137 treatment units in eight eastern states. Performance was normalised according to construction cost, projected service life and kilograms of acid load treated. Results were dimensioned as $/kg of acid load treated/year. These costs were then compared to those of chemical treatment. Sites that achieved acid load reductions at costs below those of chemical treatment were considered successful. In addition to evaluating the performance of the treatment methods, this paper describes the various passive treatment systems, their applications and performance data for individual treatment units.

Jan 1, 2003

By T. Bajpayee, L. Prosser, A. Iannacchione, G. Esterhuizen

Reducing the number of roof fall injuries is a goal of the NIOSH mine safety research program. Central to this effort is the development of assessment techniques to help identify the nature of the risks associated with working under potentially hazardous roof conditions. This paper discusses a method to determine the roof fall risk using a qualitative risk-analysis technique. The ability to determine roof fall risk has been a long-standing goal of safety professionals and could provide the kind of information needed by on-site personnel responsible for worker safety to mitigate roof fall injuries.

By Mary Ann Harrington Baker, John Trudnowski, Marietta Canty, Marek Zaluski

Three Sulfate-Reducing Bacteria (SRB) passive field-bioreactors were constructed at an abandoned mine site near Butte, Montana, to mitigate AMD emanating from a waste rock pile. Each SRB field-bioreactor contains chambers of an organic source, limestone, and cobbles. The field-bioreactors are configured differently to test the effect of different environmental conditions on the SRB. Preliminary observations indicate that, during start up and the first eight months of operation, the quantity of organic carbon supply significantly impacts the SRB activity. To date, the dissolved metals have been reduced significantly and the pH has increased.

Jan 1, 2000

By J. W. Spretnak, R. Speiser, A. M. Adair

THERE are sufficient arguments and evidence to indicate that boron should be adsorbed to existing austenite grain boundaries during the austen-itizing treatment. Accordingly, it is possible that boron contributes to the hardenability of heat-treatable steels by the reduction of the interf acial energy of austenite grain boundaries, at which sites are nucleated heterogeneously the decomposition products of austenite. Such a reduction in interfacial energy would reduce the total energy that can be borrowed in these heterogeneous nudeation processes and thus retard the initiation of transformation. This investigation was undertaken in an attempt to determine the effect of boron on this interfacial

Jan 1, 1956

By L. Xiao, P. Somasundaran

Using potassium oleate as a collector and alizarin red S as a modifying agent, selective depression of dolomite from francolite was achieved in an alkaline medium (pH > 9.0). Adsorption of alizarin reds alone on dolomite was found to be higher than that on francolite. Complimentary adsorption experiments of alizarin red S and oleate showed that oleate adsorprion was increased in the presence of alizaring red S. The results are explained in terms of comparative adsorption for the active sites on francolite and dolomite by oleate and alizarin red S and their interactions with dissolved mineral species in solution.

Jan 1, 1990

By Neil Styler

This paper presents an analysis of measurements of inter-burden deformations above six longwall faces. An attempt is made to demonstrate some correlation between the movements at the various sites, and to examine their importance with respect to predicting caving height, disruption of overlying seams, and disruption of aquifers. This analysis demonstrates some significant differences between predicted surface subsidence, and inter-burden deformation. In addition it is shown that the caving height above a longwall face is equal to 8 to 12 times the extraction height, with a zone of fractured rock extending to approximately 50 times the extraction height above the seam.

Jan 1, 1984

By Christopher M. St. John, Michael P. Hardy

The paper discusses an approach to geotechnical monitoring of a geological repository constructed for the purpose of isolation of high-level nuclear waste, and describes the conceptual framework for development of an integrated monitoring scheme that is initiated during the earliest phases of site investigation and continues through facility decommissioning. The approach that is proposed recognizes the need to provide specific data to support the licensing process for the repository while avoiding adverse impact upon the system performance. Further, it recognizes present and inherent limitations in both the instrumentation and techniques that night be used within a monitoring scheme.

Jan 1, 1982

By R. W. Reisinger

An historic underground copper mine in Wyoming is discharging neutral but copper-laden water into a pristine creek. The EPA-deferred site qualifies for reclamation by the Wyoming Abandoned Mine Land (AML) program. The cleanup goal is to restore the discharge so that the creek can eventually support a trout fishery. Hydrological and geochemical investigations underground have suggested two sources of mine water: one clean and the other containing copper. Results of bench-and pilot-scale tests support the viability of using low-cost passive treatment techniques to reduce copper concentrations in the near-freezing mine discharge.

Jan 1, 2000

By Murray W. Grabinsky

This paper considers thickening mine tailings to dense non-segregating slurry or paste for surface disposal. The driving motivation for this initiative is the elimination of ponds, reduction in containment dams and significant decrease in water being sent to the tailings basin. This inherently reduces risks of environmental and structural failure. Some of the engineering challenges in creating a stable stack of thickened or paste tailings are identified, and possible field and laboratory testing techniques in support of design are discussed. Finally, the integration of monitoring activities into the ongoing management of the surface disposal site is considered.

Nov 1, 2002

By T. R. C. Aston

Extensive undersea coal reserves, identified in the offshore portion of the Sydney coalfield, Nova Scotia, have resulted in the implementation of a multi-year research program to develop site specific guidelines for the undersea longwall mining operations. At present, uncertainty exists regarding the applicability of the current undersea mining guidelines. Preliminary studies have revealed four potential schemes for monitoring seafloor longwall subsidence profiles: seasurface, subsea, geophysics, and direct monitoring. However, further work has indicated that the use of marine geophysical techniques may be the most effective method of identifying and evaluating seafloor subsidence profiles by comparing pre- and post-mining seafloor topographies.

Jan 1, 1990

By S. G. Haycocks, M. Karmis, C. Haycocks

Risk assessment is a primary factor in the decision to mine some near surface orebodies, such as limestone, by either surface or underground methods. Identification and quantification of risks demonstrate that environmental concerns are greater for surface operations than underground, and may include such factors as runoff, spoil piles, aesthetics, dust, and large site reclamation. Risk assessment also includes local public feeling towards surface and underground operations while considering the balance between environmental impacts and the economic effects of mining on the local community. A complete understanding of the risks involved permits a comprehensive and accurate comparison between the two mining alternatives.

Jan 1, 1992

By Jerry W. Danni, John E. Hardaway

Corporations today must comply with an ever growing number of complex and increasingly stringent environmental laws and regulations. An environmental audit program is an effective means in which to uniformly and systematically assess compliance, and to assure management that environmental liabilities are being minimized. This paper describes the design and implementation of Homestake Mining Company's environmental audit program, which has as its primary focus the objective verification of compliance with external requirements and internal good management practices. Major elements of the audit program discussed in the paper include: pre-audit preparation; on-site audit activities; and the post-audit report.

Jan 1, 1992

By C. Alexander

Stillwater Mining Company is developing a second underground palladium and platinum mine approximately 21km (13 miles) west of their existing Nye operation in south central Montana. A 5650 meter (18,550-foot) tunnel is required to gain access to the ore bearing horizon (J-M Reef). Access and primary mine development can be accelerated through the use of two 4.6 meter (15-foot) diameter tunnelboring machines (TBM). One TBM was purchased new while the other was purchased used. Machine specifications, site support facilities, portal/launch chamber construction, TBM assembly, startup and operation are discussed in this paper.

Jan 1, 1999

Extensive infrastructure construction works were required for the development of the underground and open-cut coal mine at Ulan to a production capacity of 5 million tonnes of steaming coal per annum. The Ulan Mine development project was constructed in a two year period at a cost of $240 million. The infrastructure component included the construction of the mine site building works, civil works and 150km of railway, valued at $105 million. These works were successfully completed under a construction management agreement within two years. The separate elements of the project are described in detail in the paper.

Jan 1, 1983

By Thomas A. Earl

Much of the strip mining in the Appalachian coalfields was done prior to backfilling and regrading requirements, resulting in many devastated areas which also have serious acid mine drainage problems. Economic incentive or justification for reclaiming these thousands of acres of land does not exist unless some value can be attached to the open cuts and weathered overburden piles. In Pennsylvania many of these old strip mine cuts are being successfully used for sanitary landfills and sludge disposal sites, and multiple benefits are realized. Given proper regulatory control, this technique could be beneficially applied to many other areas in the east.

Jan 1, 1977

By William Everett, Jack Eloranta

United Taconite is an iron ore mine operated by Cleveland-Cliffs Inc (Cliffs) located near Eveleth, Minnesota. The mine, originally known as Eveleth Taconite Mines, was purchased in December 2003 by Cliffs (70%) and Laiwu Steel (30%). The mine site, known as the Thunderbird Mine, produces taconite ore for delivery by rail to the company’s Fairlane plant, located approximately 10 miles to the south near Forbes, Minnesota. At the plant, the crude ore is ground, concentrated and processed into pellets for steel industry customers. Total pellet production capacity is about 5.4 million long tons (Ltons) per year.

Jan 1, 2006

By A Mulyadi, J Barber, R Golden

The Deep Ore Zone (DOZ) underground mine will be a 25 000 tpd mechanised block cave operation starting production in 2000. The ore handling system consists of a direct truck dumping 54 +74 gyratory crusher, which feeds into an ore bin. An apron feeder below the bin is used to load a conveyor belt. This paper describes the design, sequencing and methodology of the crusher station, ore bin and feeder chamber excavations. The Geotechnical investigation and analysis of the site are also discussed as well as the design, installation and quality control of the long-term ground support methods.

Jan 1, 2000