Annual Meeting 2009 Technical Program

7/27/2019 Annual Meeting 2009 Technical Program

http://slidepdf.com/reader/full/annual-meeting-2009-technical-program 1/58

design method was proposed based on extensive U.S. field measurements whichaccounted for confinement effects. Measurements in seven U.S. seams indicatedhighest strength for Utah mines where the coal seam developed high confiningstresses. Lower strength was measured in structurally controlled seams. Thismethod is expanded to include data from weaker tertiary coal measure rocks andlower confinement for pillars with low width-to-height ratios. How much load apillar is expected to take is partially dependent on the ability of overburden totransfer load laterally; this is useful for panel width selection and barrier pillar sizewhere long-term stability is required. In caving systems, strata caving is influenced

by geologic, mining and stress conditions and the released energy influencespillar reaction at loads approaching pillar strengths. Overburden deformation andcaving mechanisms are analyzed in this paper in multi-panel extractions toenhance the understanding of load transfer, seismicity and coal bump control.

2:45 PM

Coal Mine Burst Prevention Controls

A. Iannacchione1 and S. Tadolini2; 1University of Pittsburgh,Pittsburgh, PA and 2Minova Americas, Georgetown, KY

Coal mine bursts have represented a major hazard for U.S. mining operations formore than 90 years. During this time, many prevention controls have beendeveloped and tested. This paper reviews 11 prevention control techniques.Although coal mine bursts are not common events in most underground coalmines, their occurrence almost always requires a change in mining practice. Overthe many years of dealing with these hazards, specialized requirements for

layouts and novel extraction sequences have been developed on a site specificbasis. The keys to mitigating risks are to properly assess the coal burst hazardsand to possess the knowledge and skills to prevent or remediate their occurrence.

3:05 PM

Comparison of the Mark-Bieniawski and Wilson Pillar Equations

Using Site Specific Data

V. Scovazzo; John T. Boyd Co., Richlands, WA

This paper compares the two most common pillar design equations usedworldwide by John T. Boyd Company; the Mark-Bieniawski Equation, an empiricalapproach, and the Wilson Equation, an analytical approach. The equations arecompared by their stress profiles and by the Mark-Bieniawski Equation stabilityfactor. Contrasting the two equations based on the visual comparison of theirstress profiles is straight forward but evaluating their resulting pillar designs isproblematic. Complications arise due to the differences between the use anddevelopment of stability factors for empirical equations and safety factors for

analytical equations. To work around these differences, comparisons are madebetween the two equations by calculating pillar sizes using the Wilson Equationand then determining the Mark-Bieniawski Equation stability factor for thesepillars. Pillars designed using the Wilson Equation were based on site-specificdata from 23 mines located in the Americas and Australia. Comparing pillar sizedesigned by the Wilson Equation to the Mark-Bieniawski Equation; the WilsonEquation pillar sizes were smaller in 77% of the cases, similar in 3%, and largerin 20% of the cases.

3:25 PM

A First Step in Developing Standing Roof Support Design

Criteria Based on Ground Reaction Data for Pittsburgh Seam

Longwall Tailgate Support

T. Barczak, G. Esterhuizen and J. Ellenberger; NIOSH, Pittsburgh, PA

Roof support systems are designed for roof control to prevent unplanned falls. It

sounds logical and has been the conventional thinking in support design sincesupports were first installed. In order to determine which support system shouldbe used or which would be the most effective, the degree of control provided bythe support system must be known. This question embodies the concept of aground response curve, which is a measure of suppor t control by assessment ofthe convergence in the mine entry as a function of the support capacity. In thisNIOSH study to optimize standing roof suppor t design, ground response curveswere developed for longwall tailgate conditions from numerical models ofPittsburgh Coal Seam geology. The models were calibrated against tailgateconvergence measurements that were made in two Pittsburgh Coal Seam minesas the depth of cover varied during the panel extraction. Ground response curveswere developed for loading conditions including development, side abutment, frontabutment near the longwall face, and full extraction inby the face. In general, thetailgate convergence and required support capacity increase through each ofthese loading stages.

Technical Program

35

Monday, February 23 Afternoon

DRYER LECTURE

2:00 PM • Monday, February 23

Lecturer: Stephen Leary

“The Fruta Del Norte Epithermal Gold-Silver Discovery, S.E. Ecuador”

Coal & Energy: The Best of Ground Control


Chair: S.Tadolini, NIOSH - Pittsburgh Research Laboratory,

Pittsburgh, PA

2:05 PM

Evaluation of a Multiple Seam Interaction Coal Pillar Bump

M. Gauna1 and S. Phillipson2; 1MSHA, Pittsburgh, PA and 2MSHA,Pittsburgh, PA

An evaluation and analysis of a coal pillar bump in a West Virginia mine indicatedthat the bump occurred because of the unique combination of controlling factors.The pillar’s development stability factor of 2.6, based on Mark-Bieniawski strengthand tributary loading, would typically indicate an adequate pillar size for long-term main entries. A combination of multiple-seam mining geometry andgeological conditions resulted in stress concentration leading to the coal pillarbump. No high extraction mining had been performed in the area and the

overlying works appeared to have adequate stability factors. However, it wasinterpreted that long-term flooding had softened the overlying pillar system andrendered all but the largest pillars ineffective. Contributing factors include largeoverlying pillars transmitting stress through the approximately 60 ft of interburdenand the failed pillar’s location at a transition in the immediate roof from shale tohard, massive sandstone; mining of the pillar smaller than surrounding pillars inan attempt to avoid the channel; high overburden of 1,100 ft; and the pillar’sposition in the bottom of a trough within the coal horizon.

2:25 PM

The In-Situ Pillar Strength and Overburden Stability in

U.S. Mines

H. Maleki; Maleki Technologies, Inc., Spokane, WA

Prudent design of coal pillars requires an estimation of in-situ pillar strength,overburden lateral load transfer capability, and a failure criterion. A new pillar



Construction Materials & Aggregates: Urban Mining


Chair: K. Oakes, Olson Explosives, Inc., Decorah, IA

2:05 PM

“Big Multi-Seam Happenings in Northeast, Iowa” – A Story of

Vision, Development, and Working Together to Break Ground on

a New Greenfield Operation

K. Oakes2 and S. Krivachek1; 1Olson Explosives, Inc., Decorah, IA and2Operations, CJ Moyna & Sons / Moyna materials, Elkader, IA

In January of 2007, CJ Moyna & Sons of Elkader, IA, in a joint / team developmentconcept with Pattison Sand Company of Clayton, IA broke ground and begandevelopment of a large dual resource; surface, industrial sand / aggregateoperation near the communities of Clayton and Frenchtown on the banks of theMississippi River in Clayton County, Iowa. The operation is made up of multiplecommercially marketable quality members of limestone, dolostone, and industrialgrade sandstone at a current development depth of 200 feet. The finishedindustrial sand product is being shipped by rail to Oklahoma, Texas, and Canada.The limestone/dolostone is being produced and marketed as a high quality IowaDOT approved concrete aggregate, shipped by both rail and truck to end usecustomers, one of which is the largest concrete paving project that was let by theState of Iowa in 2007.

2:25 PM

The Start Up and Operation of a Greenfield “State of the Art”

Frac Sand Facility in an Environmentally Conscious Community

R. Budinger; Production / Operations, Wisconsin Industrial Sand / Fairmount Industrial Minerals, Menomonie, WI

This paper will describe our business and markets with a brief introduction,describing Fairmount Minerals Corporate Responsibility and SustainabilityCommitment, leading to a Discussion on the evolution of the Blasting Program. Itwill explain how Fairmounts philosophy and reputation as a leader in the IndustrialMinerals Marketplace has helped during public hearings We intend to give anupdate on the project operations as it stands today with photos; etc. We willdiscuss the LEED Certification for the Office and Shop Facilities. We intend todiscuss some of the incentives we are anticipating through the “Focus on Energy”Program for the installation of high efficiency motors and VFDs.

2:45 PM

Programmable Electronic Detonators - Not Just for Vibration

ControlK. Oakes and D. Wenzel; Olson Explosives, Inc., Decorah, IA

Since the introduction of programmable electronic detonators in the late 1990’s,most operators have viewed them as a tool to assist them in reducing the effectsof blast induced vibrations, however, they have been proven to show significantadditional benefits throughout the entire crushing ans srenneing circuit, as wellas allowing the respective operators shoot larger shots less frequently, additionallyadding to their “bottom line” with reduced downtime due to blast frequency. Thispaper will discuss the various “non-traditional” benefits seen through theincorporation of programmable electronic detonators, and why.

3:05 PM

Minimizing Risk in Urban Quarries (Two Case Studies)

W. Reisz1, J. Goldberg2 and S. Zadra-Goldberg3; 1Davey Bickford USA,Huntingburg, IN; 2Lehigh-Hanson / Heidelberg Cement Group,

Thorton, IL and 3Engineered Dimensions, Inc.Cement Group,Buford, GA

Early recognition and risk assessment is critical to sustaining a safe andproductive blasting operation. While every blasting environment holds inherentrisk, highwall blasting in highly congested areas such as Hanson HeidelbergCement’s Romeoville and Thornton quarries in the south Chicago area can beparticularly perilous. At Romeoville, 140 foot highwalls face Illinois Route 53. TheThornton Quarry straddles Interstate 80, one of the busiest highways in NorthAmerica. Areas with severely dipping bedding planes, vertical fractures andsolution cavities add to the risk and contribute to the complexity of the blast design.Although public and personnel safety is always the primary concern, vibration andproduction levels must also be considered. Rock modeling is accomplishedthrough 3D laser modeling and borehole path probes. Blast plans include the useof digital detonators for energy control and design flexibility. Although many of theproblems have deep rooted cause and effect, often it’s the simple solution thatworks best. This paper will describe some of the challenges faced, as well as thecollaborative processes and techniques used to address these critical areas.

Environmental: Environmental Management, International


Chair: P. Acker, Goldcorp, Englewood, CO

2:05 PM

External Codes and Corporate Credibility

J. Allan; Goldcorp, Inc., Vancouver, BC, Canada

The rise of NGOs, and the more activist nature of civil society in general, haslead to the development of a number of codes and similar external instruments.Some of these, such as the International Cyanide Code, are aimed specifically atthe mining industry. Others, such as the UN Global Compact, are much moregeneral in nature, but are being used to measure performance in the industry.With increasing pressure from external entities, how do companies choose whichcodes to adopt, and how do they achieve successful implementation? Goldcorphas successfully used both the top-down approach and bottom-up approach inimplementing key external codes across the Group.

2:25 PM

Erosion and Sediment Control Plan Implementation, Los Filos

Mining Project, Mexico

A. Sierra; Minero Los Filos, Mezcala, Mexico

The Los Filos Project is located in mountainous terrain in the State of Guerrero,southern Mexico. The average annual precipitation is 150 mm, most of which fallsbetween June and September. Uncontrolled waste rock disposal during historic

mining activity has resulted in erosion and the sedimentation of streams within theLos Filos Project area. Disturbance from exploration activities in the terrain hasalso caused erosion. In 2006 project construction was initiated, increasing thearea of disturbance at the site. As part of the environmental assessment andenvironmental management planning for the project, the need for site-widesurface water management and sediment control plans was identified. During the2007 rainy season high intensity storms resulted in the movement of largequantities of sediment from the historic and new disturbance of the site,emphasizing the need to implement these plans. This paper will discuss theimplementation of a site wide erosion control program at Los Filos, focusing onthe short-term measures used for establishing “source control” prior to the 2008rainy season.

2:45 PM

Implementation of the International Cyanide Code at Goldcorp

Inc.’s Marlin Mine in Guatemala

P. Hughes-Hallett; Montana Exploradora de Guatemala, S.A., Ciudadde Guatemala, Guatemala

The Marlin Mine is a gold mining and milling operation located in Guatemalaapproximately 120 kilometers northwest of the capital, Guatemala City. GoldcorpInc. became signatory to the International Cyanide Management Code (the Code)in June 2007 and Goldcorp’s Marigold Mine became the first mine certified underthe code. The Marlin Mine received the third par ty Gap Analysis in May, 2008 inanticipation of the formal audit for certification scheduled for late 2008. CyanideCode certification includes some special challenges in Guatemala such as the in-country availability of adequately trained and serviced transportation contractors.This paper will describe the special challenges faced during the Cyanide Codecertification process and their subsequent resolution.

3:05 PM

A Risk-Based Approach to the Development of Wildlife

Monitoring Programs at Gold Mine Tailings Facilities

N. Overdevest; Goldcorp Mexico, Durango, Mexico

A risk-based approach to wildlife monitoring on tailings dams is a holistic andsystematic approach that is different to traditional monitoring programs. Itconsiders all aspects of a facility, including design, size, location and habitatprovisions and uses this information, in conjunction with characteristics andbehaviours of species known to frequent the site, to determine potential impacts(risks). Based on this information, management strategies to minimise or eliminatethese risks can be developed in a cost effective and practical manner. The risk-based approach can also be used to address requirements of the InternationalCyanide Management Code which requires the monitoring of wildlife to beconducted in a uniform and consistent manner.

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Environmental: Microbial Technologies: Assessment,Treatment and Passivation


Chair: L. Figueroa, Colorado School of Mines, Golden, CO

2:05 PM

Geochemical Stabilization of Mining Impacts Through

Biotransformation of Iron Minerals

J. Gillow1, J. Horst2 and A. Getahun1; 1ARCADIS U.S., Inc., HighlandsRanch, CO and 2ARCADIS U.S., Inc., Newtown, PA

The treatment of inorganics associated with mining residuals requires that equalconsideration be given to the solid phases as to the aqueous phases. Becauseof its chemical nature and relative abundance, the role of iron in controlling themobility of many inorganics is significant. One way in which iron can be harnessedis through the biologically-mediated transformation of iron within anddowngradient of an in-situ anaerobic treatment zone. This involves a variety ofpossible mineral transformations, but of primary importance are the formation offresh iron sulfides within the anaerobic zone, and the formation of fresh oxy-hydroxides in the downgradient area. This can rely on biogeochemicaltransformation of natural iron present in aquifer soil and available sulfate, but canalso be engineered with a supplemental source of iron. The in-situ precipitationof insoluble forms of uranium can be accomplished under anaerobic and reducingconditions, but a critical component to this approach is the creation of excessreductive poise (through the concurrent mineralization of iron sulfides) to bufferthe environment over the long term and mitigate reoxidation of the precipiateduranium.

2:25 PM

Performance of Ethanol Fed Sulfate Reducing Bioreactors for

Metal Removal from Mining Influenced Water

C. Venot; Environmental Science and Engineering, Colorado Schoolof Mines, Golden, CO

The use of ethanol as an organic substrate for sulfate reducing bioreactors hassome advantages over solid phase organic matter typically used in SRBRs.Ethanol is well suited to mining influenced water (MIW) treatment because is isrelative inexpensive, does not freeze and targets growth of sulfate reducingbacteria directly. Pilot-scale evaluation of a pair of ethanol fed SRBRs hasdemonstrated two years of successful removal of dissolved metals.

2:45 PM

Preventing Pyrite Oxidation: A Geomicrobial Strategy for SourceControl of Acid Mine Drainage

J. Silverstein1, H. Rajaram2 and J. Jenkins3; 1CEAE, University ofColorado, Boulder, CO; 2CEAE, University of Colorado, Boulder, COand 3Geomatrix Consultants, Inc., Denver, CO

This research project is a study of the feasibility of using carbon substrate additionfor in-situ bioremediation of acid mine drainage. The coupling of microbialcommunity composition and fundamental biogeochemistry at the rock-waterinterface with flow and transport processes through waste rock formations wasstudied in laboratory experiments at scales of a single rock fragment and waste-rock columns. Addition of glucose resulted in a shift in the dominant bacterialpopulations from autotrophic to heterotrophic metabolism reducing oxygenavailabe for iron oxidation, decreasing soluble iron, acidity, sulfur and metalleaching. We also investigated the influence of hydrologic variables (e.g. formationsaturation conditions, water detention time) and rock properties (e.g. porosity) onthe effectiveness of stimulating heterotrophic bacterial growth to inhibit AMD

generation.

3:05 PM

Pore-scale Rate Model of Acid Rock Drainage Geochemistry and

Geomicrobiology

B. Andre, H. Rajaram, J. Silverstein and T. Yacob; CEAE, University ofColorado, Boulder, CO

Two key reactions of acid rock drainage (ARD) formation are oxidation of pyriteby ferric iron and oxidation of ferrous iron. Both are rate controlled processesaffected by pH, oxygen, and the growth rate of iron-oxidizing bacteria. Laboratorystudies of the kinetics of microbial and chemical reactions were conducted anddata fitted to rate expressions by a non-linear regression method. Kineticparameters, equilibrium chemistry conditions, and oxygen transport rates werecombined to develop a pseudo-homogeneous (continuous stirred tank reactor)model of ARD generation at the pore scale. Model calculations suggest that therate-limiting step in ARD generation is oxidation of pyrite by ferric iron, when

3:25 PM

Environmental Legislation in Mexico

H. Perez; Goldcorp México, Durango, Mexico

Traditionally environmental legislation in Mexico has been considered as beingdeficient when compared to international legislation. However, over the last fewyears; laws, regulations and official rules have been updated and developed as ameans of bringing environmental management in-line with internationalstandards. Mexico’s new Waste Law and rules for operating tailings dams, as wellas the new form of managing mining industry agreements during the closureprocess, demonstrate the progression and new form in which environmentaladministration is being carried out within Mexico.

3:45 PM

Wildlife Monitoring at Goldcorp’s San Dimas Mines, Mexico

M. Rivas Garcia; Goldcorp México Distrito San Dimas, Tayoltita,Mexico

The San Dimas Mining District, located in the Sierra Madre mountain range andapproximately 125km from the Pacific coast, has been the site of mining activitiesfor over 100 years. Because mining activities commenced prior to theestablishment of environmental regulation, very little to no information has beenavailable on the district’s fauna. Recently, a wildlife monitor ing program has beendeveloped to meet the requirements of the Goldcorp’s corporate CyanideManagement Standard. This has been the catalyst for expanding the monitoringprogram to other areas of the district to develop an understanding of the district’slocal fauna. The gathering of this information has been a useful tool not only inimproving the understanding of the functioning of the local environment but alsoin raising the awareness and interest towards the protection and care of local

species within the local community.

4:05 PM

Rescue Program for Flora, Fauna and Topsoil, Peñasquito

Project, Mexico

R. Martínez; Minera Peñasquito S.A. de C.V., Saltillo, Mexico

The Peñasquito Project is a proposed open pit gold, silver, lead and zinc minelocated in Zacatecas State, Mexico. The project is under construction with fullproduction planned for late 2009. This will be a cornerstone project for Goldcorpand, at 130,000 tonnes per day, will be one of the largest mines in Mexico. Themine life of the project is currently 19 years. In October 2006, prior to the initiationof construction, the flora, fauna and topsoil rescue program began at thePeñasquito Project. The rescue program included the use of GIS, a 34-man crew,and specialized techniques for the rescue, transport and transplant of flora, topsoilexcavation and storage, and live capture and release of wildlife. To date a millioncubic meters of topsoil have been salvaged and 500,000 plants (including 10,000

protected species) have been transplanted for future use during reclamation andclosure activities. In addition 450 species of wildlife have been relocated. Thispaper will describe the rescue program and the ongoing challenges of stayingahead of construction and changes in the mine plan.

4:25 PM

Environmental Management Systems as Policy Instruments:

A Comparative Case Study of Mining and Metallurgy in the Kola

Peninsula and the Gulf of Bothnia

O. Salmi; Helsinki University of Technology, Lahti Center, Lahti,Finland

This article analyzes the role of environmental management systems (EMS) in co-aligning corporate strategy with public policy for effective environmentalgovernance. By comparing two case studies from the mining and metallurgicalindustry, the article shows how EMSs enable strategic fit in radically different

political contexts. The first case looks at the Russian Kola Peninsula where duringthe past 15 years emerging EMSs in the mining industry have come to fill the voidcreated by reduced government intervention in environmental issues. In contrast,the second case looks at the metallurgical industry around the Gulf of Bothniabetween Finland and Sweden. In this case, the presence of strong publicenvironmental policy requires a continuous renegotiation of the role of corporateenvironmental management, particularly with respect to carbon emissions andmaterial recovery. On the basis of the case studies, we develop a set of key criteriafor EMSs to function as mediators between strategy and policy. These criteria arebased on both novel regulatory solutions and the recognition of stakeholdersalience in EMS design.

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oxygen diffusion is not limited. The model will be expanded to include inhibition ofARD by organic substrate additon to promote the growth of heterotrophic bacteriaand competition for oxygen.

3:25 PM

Removal of Sr (II) From Aqueous Solutions by Using Bentonite

as Natural Adsorbent

S. Nikfar1, S. Milani2 and S. Mirhakimi1; 1Chemical engineering, ArakAzad university, Tehran, Iran and 2Nuclear Science Research School,Nuclear Science & Technology Research Institute, Tehran, Iran,Tehran, Iran

In the present study, the ability of bentonite (clay,as natural adsorbent) to removestrontium ions from aqueous solutions has been investigated. Batch method wascarried out during adsorption process. The effect of various parameters such ascontact time, initial concentration, PH, particle size and existence of competingmetal ions has been studied. Kinetic of adsorption showed that the uptake ofstrontium ions is very rapid during first thirty minutes and equilibrium time isindependent of initial strontium concentration. Simple kinetic and thermodynamicmodels have been applied to the rate and isotherm sorption data and the relevantkinetic and thermodynamic parameters were determined from the graphicalpresentation of these models. Keywords: modeling; Kinetics; Thermodynamics;Sorption; bentonite; batch operations.

3:45 PM

Concurrent Removal of Zinc and Manganese in Sulfate Reducing

Bioreactors

A. Gilbert1 and L. Figueroa2; 1Colorado School of Mines, Westminster,CO and 2Environmental Science and Engineering Division, ColoradoSchool of Mines, Golden, CO

The removal of zinc and manganese in passive treatment systems typicallyrequires at least two sequential treatment processes: an anaerobic sulfatereducing system followed by an aerobic polishing system. Reduced manganesetypically passes through sulfate reducing system untreated. Manganese can beremoved concurrently with zinc in anaerobic environments but requires specificenvironmental conditions that are not well understood. A laboratory study usingcrab scrap (the leftover material of crab processing) and synthetic mine waterdemonstrated greater than 90% removal of manganese concurrently with greaterthan 99% zinc removal. The study was conducted in column test analysis usingcrab scrap as the only organic substrate and inoculum for sulfate reducingbioreactors. The data suggest that two key components for concurrent zinc andmanganese removal under sulfate reducing conditions are elevated calcium andalkalinity concentrations. The ability to use a single passive treatment systemboth zinc and manganese removal will result in a significant reduction in requiredland area.

Industrial Minerals: Impact of China onIndustrial Minerals


Chair: F. Heivilin, HGPS LLC., Thomasville, GA

2:35 PM

Effects of China’s Export Policies on World Fluorspar Supplies

and Prices

M. Miller; Minerals Information Team, U.S. Geological Survey,Reston, VA

China’s increased production and exports of fluorspar, particularly in the 1980sand early 1990s, put tremendous downward pressure on world fluorspar prices.Chinese producers, owing to lower production costs and intense internalcompetition, sold fluorspar on world markets at significantly lower prices thancould be matched by fluorspar miners in other countries. This resulted in fluorsparmine closures in traditional fluorspar producing areas in Europe, Mexico, andSouth Africa. (Most U.S. fluorspar mines had already succumbed to lower-costMexican producers in the 1970s.) With the installation of an export license andquota system, prices increased, but for many fluorspar miners it was too late. Asa result, when China began reducing its exports, there were no fluorsparproducers with the capacity to make up for the decreased supplies of high-qualityacidspar to the world markets. This resulted in rising acidspar prices (c.i.f., U.S.Gulf of Mexico), which have increased from an average of $135 per metric ton in2001 to an estimated $350 per metric ton in 2008.

2:55 PM

Palygorskite (attapulgite) in Central China

H. Murray; Geological Sciences, Indiana University, Bloomington, IN

The largest reserves of palygorskite in the world are located in Anhui and JiangsuProvinces in East Central China. The deposits are Middle Miocene in age andrange from 3 to 6 m in thickness. The deposits are the alteration product ofbasaltic volcanic ash. The Chinese Geological Survey estimates reserves inexcess of 200 million tons. The elongate particle shape results in unique colloidalproperties. Large quantities are exported to Japan, Taiwan, Southeast Asia, NewZealand, Australia and to the West and Gulf Coasts of the U.S. The marketsinclude agricultural carriers, paint, joint tape compounds, animal feed binders,catalyst support, salt water drilling muds, and suspending agents for chemicals,pharmaceuticals, and medicines. The viscosities are high and the quartz contentis generally 5% or less.

3:15 PM

Affect of Chinese Sales on U. S. Purchases Since 1979

F. Heivilin; President, HGPS LLC., Thomasville, GA

In 1979 the Chinese sold 24,000 of 267,000 tons of calcined 80% alumina bauxiteused by the United States for refractories. In 1980 China sold 111,000 of 363,000tons purchased. However, by 1984, China supplied 78,000 of 190,00 tons.Guyana has lost 42% of its sales to the U.S. and the price has dropped from$172/ton in 1980 to $121 in 1985. China was selling bauxite for $77 in 1985. Chinahad 62% of market in 1985. Surinam dropped out of the refractory bauxite marketin the United States. Within the United States C. E. Minerals had by 1985 gainedcontrol of the Harbison Walker, A. P. Green, Wilson Snead, Grefco, and EufaulaBauxite mining deposits in the Eufaula area for making 60 and 70% aluminacalcined bauxite. The fall in refractories production in the early 1980’s contributedto the chinese take over of the market.The combining of the refractoriescompanies was a result of the lower demand for refractories in the United States.By 2007 production was back up to 282,000 tons with Brazil 93,000 tons. Guyana36,000 tons, and China 118,000 tons. Surinam is out of the picture as it has beenalmost since the start of Chinese sales to the United States. This is a big change.

3:35 PM

Bentonite and the Global Economy

D. Eisenhour; Amcol International, Arlington Heights, IL

Over the past decade global growth has fueled demand for a wide range ofmineral-based commodities; bentonite is no exception. Oil, steel, andinfrastructure development have been particularly important in driving bentonitedemand. The way in which these markets are inter-related and the central role ofChina as both a producer and a consumer will be discussed.

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GEM: LET’S ALL WORK TOGETHER: WORKING WITH

GOVERNMENT ENTITIES


Chairs: Angie Harmon, Freeport McMoRan Copper & Gold Inc.

J. Steven Gardner, Engineeering Consulting Survey, Norman, OK

Hear from individuals from government, industry, non-profit and tradeassociations about the improtance of working effectively with “thegovernment”. Realize the value of interacting with different forms ofgovernment, equipping you with the skills necessary to form effective publicand private partnerships across functions.





2:25 PM

Dynamic Simulation of Grinding Circuits as an Aid for the

Diagnosis of Hydrocyclone Malfunction

C. Bazin; Mining and Metallurgical Engineering, Laval University,Quebec, QC, Canada

Most of the grinding circuits are operated in the presence of disturbances such asore changes and equipment malfunctions. One of the challenges faced by theoperators is to detect the presence of a disturbance, to identify its origin and totake an action to correct the problem. Hydrocyclones play a strategic role in theperformance of a grinding circuit and their operation may be hampered by severalproblems. A dynamic simulator for grinding circuits was developed to help increating a tool box to assist the operators in rapidly identifying the source of adisturbance particularly in the case of hydrocyclones. The simulator accounts forthe available instruments in a circuit and typical measurement noise produced bythe sensors. Trends produced by the sensors and results of regular manualsampling are used to identify the disturbances in parallel of the simulatoroperation. Since different disturbances may exhibit similar signatures (change of% solids, pump speed, final product D80…) in a noisy environment, it is onlypossible to attribute a probability of realization of disturbance, which can howeverbe helpful for allowing a fast pinpointing of the source of a problem.

2:45 PM

The Effect of Demagnetizing Coil on Hydrocyclone Performance

S. Ersayin1 and R. Strukel2; 1Coleraine Minerals Research Lab,University of Minnesota, Coleraine, MN and 2Minorca Plant,ArcelorMittal, Virginia, MN

Use of magnetic separators prior to hydrocyclone operation causes magnetite

particles flocculate. These particles end up in the underflow and are unnecessarilycirculated back to the ball mill. A plant scale study was conducted to investigatethe effect of demagnetizing coil to alleviate this problem. The coil was installed inone of the lines. Hydrocyclone feed and product streams were sampled whiledemagnetizing coil was on and off. The sampling survey was repeated for threedifferent cyclone operating pressures within a short period of time to eliminatefluctuations due to cyclone wear. Size distribution and size by size magnetic ironcontent of samples were determined. Then, partition curves were constructed tocompare the two data sets representing each cyclone operating pressureconditions with and without demagnetizing coil. Each set of cyclone data wasfitted to a model and used in plant simulations Findings of this study will bepresented in the paper.

3:05 PM

General Repair Improvement Process

C. Asgaard1, R. Phelps3 and T. Feller2; 1Shared Services, Cleveland-Cliffs, Ishpeming, MI; 2continuous Improvement, cleveland Cliffs,Ishpeming, MI and 3Consultant, Sinclair and Associates,Knoxville, TN

The Empire concentrator was built in four stages, with the latest most costeffective stage accounting for 50% of the overall plant capacity. This was the targetarea for this Project. Prior to the project, availability of the target mills decreasedto 68% with general repairs taking an average of 14 days to complete. This paperdiscusses the improvement process that decreased the repair time significantly,while increasing overall line availability. These improvements permitted sidelingless efficient equipment providing cost savings in the millions, while still makingbudgeted product. Specific areas of improvement are reviewed, including, workidentification, planning, repair definition, scheduling-(CCPM), lining prep, workexecution, post repair analysis, and process improvement.

3:25 PM

How to Increase Plant Performance with Artificial Intelligence

and Expert Systems

L. Hales, M. Hales, C. Burbidge and D. Collins; KnowledgeScape,Salt Lake City, UT

In the minerals industry we have been using expert systems to increase plantthroughput rates and recovery for over thirty years now. Plant improvements,although significant, by-in-large have plateaued. A historical review of how artificialintelligence has been used will be reviewed along with the reasons performancehas plateaued. Understanding the reasons improvements have plateaued pointsus in new directions and newer artificial intelligence concepts and methods toonce again step up plant performance from the best performing expert systems

in use today.

3:45 PM

Using the Classifiers to Improve Energy Efficiencies of Grinding

Circuits

A. Mainza; Chemical Engineering, University of Cape Town, CapeTown, South Africa

Comminution consumes most of the energy in concentrator operations. Energyconsumption increases significantly in circuits where fine grinding is required.Comminution circuits closed with classifiers are commonly practised in theminerals industry to control the product size. The energy consumption in closedcircuit applications has a strong dependence on the operation of the classifier.For circuits designed to produce a finer product at moderately low throughputssingle stage closed circuit operations have an advantage. In this type of circuit thekey to minimising energy consumption is operating with a low circulating rate of

fine material. The long history of using closed circuit single stage has shownencouraging energy utilisation results and this may become more impor tant withthe global high energy demands. Like any closed circuit, the relative merits ofsingle stage circuits are closely associated with the design and operation of theclassifier. Improvements in fine screening technology will provide an opportunityto further reduce the circulation of fine material in comminution circuits leading toimproved energy utilisation and to operate at increased throughputs.

Mineral & Metallurgical Processing:New Projects/New Opportunities


Chair: J. Lommen , Consultant, Socorro, NM

2:05 PM

Evaluation of Novel Clay Depressants in Iron Ore Flotation

D. Tao1, X. Zhou1, J. Hines2 and D. Kennedy2; 1Mining Engineering,University of Kentucky, Lexington, KY and 2Georgia-Pacific Resins,Inc., Decatur, GA

The reverse cationic flotation is the most widely utilized flotation method forconcentrating iron ore. In such a process quartz is often floated with ether amines(R–(OCH2)3–NH2) partially neutralized with acetic acid. However, it is well knownthat the cationic flotation of hematite does not work well if much slime is present.To improve flotation performance, starch is often added to the flotation feed toselectively flocculate and depress the iron minerals and sodium silicate is usedto disperse the silica gangue. The present study was conducted to improve theflotation efficiency of iron flotation by use of a new type of depressant for clay andiron minerals, i.e., GP clay binder. The GP clay binder minimizes slime adsorptionon quartz and hematite particles by agglomerating clay particles to reduce theirsurface area. It also helps depress hematite flotation due to its unique chelatingability to iron ion. It has been demonstrated that the combined use of GP claybinder and starch improved concentrate grade from 60.8% to 67.1% andincreased iron recovery from 72.0% to 78.2% while the collector dosage wasreduced significantly.

2:25 PM

More Efficient Leaching: Using Controlled Source-Frequency

Domain Magnetics to Optimize Solution Distribution

V. Kofoed; Willowstick Technologies, Draper, UT

This paper considers an emerging method for rapidly determining the distributionof leaching solution in a heap. The procedure, which uses Controlled Source-Frequency Domain Magnetics, begins with the insertion of electrodes into theheap structure. The resulting electrical current naturally gathers in the mostconductive zones (i.e., the most saturated areas of the heap). This current emitsa magnetic field (Biot-Savart Law), which can be captured by a specially tuned

40

Photo from Denver Metro Convention & Visitors Bureau



reciever and analyzed to determine the distribution of the solution. Properlyfiltered, this data supports two-dimemensional maps and three-dimensionalmodels of the distributed solution, providing critical information in the effort toproduce more uniform saturation throughout the heaped material. This paper willconsider the lessons learned through the recent applications of this promisingprocedure.

2:45 PM

Changing the Way Iron Ores are Characterised Using Automated

Mineralogy

A. Benedictus1, H. Horsch2 and A. Butcher1; 1Science and Technology,Intellection Corporation, Brisbane, QLD, Australia and 2Global

Technical Group (Customer Service), Intellection Corporation,Brisbane, QLD, Australia

Over the past few decades, the implementation of automated mineralogy hasbeen increasing within the mining industry, but iron ore has been lagging behind,mainly due to the perceived and real difficulties of differentiating economic ironoxides and hydroxides by electron beam-based instruments. This situation hasbeen improved recently, with the development of a new iron ore capability forQEMSCAN®, which now has the capability of accurate identification and texturalquantification of metallic iron, magnetite, hematite and goethite, as well ascommon gangue phases. Using this new information, iron ore companies are ableto better monitor and optimise the quality of their feed ores and ultimate products.This paper deals with how we have overcome the challenges in the automateddifferentiation of iron phases, and includes several case studies from classicmetallogenic provinces.

3:05 PM

A New Process Treating and Utilizing High Alumina Limonite

Ores

T. Jiang, G. Li, X. Fan and M. Liu; School of Minerals Processing &Bio-engineering, Central South University, Changsha, China

Large reserve of high alumina limonite ores are widely found in Indonesia, China,etc. Traditional processing processes, such as magnetic separation, flotation,magnetization roasting-magnetic separation, are difficult to separate aluminiumand iron from this type of ores due to the close combination of aluminium with ironminerals. A new process—salt added roasting-magnetic separation wasdeveloped by the authors to treat and utilize the ores. By the process, a metalliciron concentrate with the iron grade above 90% and aluminium content below 1%was achieved in laboratory for a sample of 48.85% iron and 7.86%Al2O3. Therecovery of iron in the concentrate was greater than 90%. This paper will involvethe fundamentals and technologies of the process.

3:25 PM

Significance of Measured and Modeled Unsaturated Flow resultsin Heap Leach Materials using Large Diameter Column Tests

V. Galla1, D. Van Zyl2 and S. Morrow3; 1Mining Engineer, NewmontMining Corporation, Battle Mountain, NV; 2Mining Engineering,University of British Columbia, Vancouver, BC, Canada and 3AppliedSoil Water Technologies, Sparks, NV

In the present paper, two large diameter columns six feet tall and four feetdiameter filled with crushed (finer) and run off mine (coarser) heap leach materialsrespectively were used to perform unsaturated flow studies. Instrumentsmeasuring moisture content and matric suction were placed in the columns atdifferent depths as water was applied at calibrated flow rates from the top of thecolumns. The outflows from the columns were recorded using tipping bucket raingauge placed at the bottom of the columns. Unsaturated hydraulic parameterswere also obtained for the heap leach materials, scalped (passing 4.75 mm sievesize) and whole (passing 37.5 mm sieve size) sample. The measurementsobtained from the columns were later compared with unsaturated flow modeling

results. The comparison indicated sensitivity towards the sample size selection forunsaturated hydraulic parameters, and initial conditions considered in the model.

3:45 PM

Process Development of the Tenke Fungurume Copper and

Cobalt Project in DRC

D. Meadows; Freeport-McMoRan Copper and Gold Company,Phoenix, AZ

Located in Katanga Province, Democratic Republic of Congo, the TenkeFungurume concession embodies a true, world-class copper and cobalt resource.This paper describes the Tenke flow sheet process development for both thecopper and cobalt circuits, which entailed thorough reviews of historical test work,bench-scale test work and, ultimately, a series of integrated pilot plant campaigns.Copper processing incorporates crushing, grinding, leaching, counter currentdecantation, solution extraction and electrowinning. The initial cobalt circuit

encompasses sequential impurity removal steps before precipitation of a salablecobalt hydroxide product; the cobalt refinery entails additional base metal impurityremoval steps and electrowinning, yielding a cathode with 99.8% purity. Designchallenges associated with ore treatment are discussed, as is the path forward foroperation and expansion.

Mining & Exploration: Step Change Mine Technologies


Chair: S. Holmes, Freeport-McMoRan, Safford, AZ

2:05 PM

Advanced Navigation in Open Pit Mines

S. Holmes1 and K. Zimmerman2; 1Freeport-McMoRan, Safford, AZand 2Novarient Technology, San Jose, CA

Advances in navigation technology are enabling high precision navigation controlto be achieved in even the deepest and most remote open pit mines. Newtechnologies, including advanced inertia navigation and ground based satelites orpsuedolites have made it possible to know exactly where people and equipmentare located in real-time. This presentation reviews the current state of theindustryand focuses on the expanding use of psuedolite technology in the mining industry.

2:25 PM

Fragmentation Optimization - Real-Time SPLIT

S. Holmes, S. Grandone and R. Dean; Freeport-McMoRan, Safford, AZ

Fragmentation within the mine is often overlooked as a critical element in themining process. SPLIT digital fragmentation technology has been available forsome time, but requires field set-up and calibration to obtain the digitalphotographs needed for evaluation to get a reliable size distribution of the blastedmaterial. The Mine Technology Group (MTG) of Freeport McMoRan hasdeveloped the real-time application of SPLIT analysis to support the company’sSTOMP or Sized To Optimize Mine Process program. In addtion, MTG has workedwith SPLIT and P&H to improve the algorithm and auomate the process to allowthe company to measure size distribution from the mining face at any time. Thisdata is extremely valuable to D&B operations for use in determining the endresults of their drill and blast design. This presentation will describe Real-TimeSPLIT utilization at Freeport McMoRan and how this new technology is changingthe way modern minig is done.

2:45 PM

Collision Detection and Avoidance in Open Pit Mines

S. Holmes and J. Carpenter; Freeport-McMoRan, Safford, AZ

Collision detection and avoidance in open pit mining operations has long been adifficult goal for all mining company’s. As hualage and mining equipment havegrown bigger and mining operations larger the frequency of severe, and oftenfatal incidents from collision has increased. New technologies are now emergingthat help operators avoid collisions and maintain safety. This presentation willinclude new generation collision avoidance technology using a combination ofadvanced wireless radio technology, GPS/XPS navigation control, and aneffective interactive touch control screen for operators that Freeport McMoRan, inconjunction with Motorola and NIC, has produced that is being trialed at Freeport’soperations in the US.

3:05 PM

LSM: A Major Breakthrough in Mass Material Transportation

S. Holmes and E. Robinson; Mine Technology Group, Freeport

McMoRan, Phoenix, AZ

As open pit mines mature and get deeper the cost of haulage increasesenourmously forcing many company’s to consider converting to underground.Major OEM’s have helped by producing 400T class trucks, but these giantmachines may not be a cost effecive solution. Standard and high-angle conveyorsystems can be productive, but are capital intensive and are inflexible. LSM is anew, step-change mass material transportation technology being developed byFreeport McMoRan, in association with MagnaMotion, Inc., AKIC, LaMar Techand others, for deep pit mining and may have underground applications as well.LSM uses the innovation of linear synronous motor technology matched withmagnetics to efficiently and reliably move pendulous skips continuously out of thepit - without an in-pit crusher! It’s the new mining industries industrial productionroller coaster.

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attention in three areas: (1) Air emissions; (2) Water effluents; and (3) Solidwastes. In order to ensure that the industry will not only meet existingenvironmental regulations, it is prudent to completely eliminate all wastes in sothat any plausible future environmental regulations will be met.

2:41 PM

Novel Use of Polymers in Canadian Oil Sands Processing

Z. Xu and J. Masliyah; Chemical and Materials Engineering,University of Alberta, Edmonton, AB, Canada

Bitumen production from oil (tar) sands represents a Canadian success story.With good processing ores, bitumen recovery often exceeds 90%. However, forhigh fines ores, bitumen recovery could drop significantly, as low as below 50%.

Our earlier study identified that slime coating of fines in the presence of divalentcations on bitumen is a major cause for the decreased bitumen recovery and poorfroth quality. To improve the processability of high fines ores in terms of bitumenrecovery and froth quality, flocculation of fines by polymeric flocculates wasproposed. Flocculation of fines would minimize slime coating of fines on bitumen,leading to increase bitumen recovery and improved froth quality. Selectiveflocculation of fines by a combination of a partially hydrolyzed polyacryamide andan aluminum hydroxide-polyacryamide hybrid was proven to improveprocessability of high fines ores. At the same time, selective flocculation led tosignificant improvement in tailings settling, allowing quick recycle of process waterand improving tailings management. Our study emphasizes a holistic approachin process improvement.

2:59 PM

An Integrated Approach to Mineral Sulphide Tailings

Management and AMD Mitigation

A. Hesketh; Dept of Chemical Engineering, University of Cape Town,Rondebosch, South Africa

AMD is one of the major challenges facing the mining industry. Changes inlegislation put perpetual responsibility for waste management on miningcompanies, creating a need for new approaches to AMD mitigation over the long-term. Current philosophy in the management of waste disposal in base metalsmining focuses on an end-of-pipe approach which is yet to show sustainability.Various authors have shown the importance of taking a systemic approach toAMD through the identification and prediction of potential harm with the aim ofreducing long-term environmental impacts and costs of AMD remediation.Literature has shown the feasibility of using flotation for the desulphurisation ofsulphide tailings producing a benign tailings stream and a sulphide-rich product.This paper discusses the viable downstream options for these waste fractions. Awaste management framework to provide a walk-away status for waste disposalis investigated with emphasis placed on a holistic approach to pollutionminimisation. This research also provides a basis for the identification ofopportunities for the development of new process designs incorporating waste

management systems for mitigation of AMD.

3:17 PM

Chemically Enhancement of Physical Separation Technologies:

Electrostatic and Magnetic Separation

S. Ravishankar; Cytec Industries Inc, Stamford, CT

The physical separation technologies of minerals exploit the differences betweenproperties such as gravity, magnetic susceptibility or surface electricalconductivity. The separation efficacy suffers when the feed constitutes finerparticles and coated with surface contaminant resulting in production rate andproduct purity issues. Cytec Industries has been developing chemicalenhancement technologies for physical separations. The major advantages ofchemical enhancement technology to magnetic and electrostatic separationinclude: simple extension to existing magnetic and electrostatic separationtechnology to produce quality products, ability to produce comparable product inquality with cost effectiveness compared to incumbent technologies, removal of

impurity minerals over wide size range, removing non-magnetic impurities,reducing the recirculation load in case of electrostatic separation and providingsimilar process flow combined with sustainable robust process. This paper willexemplify minerals systems including kaolin, carbonate, talc and heavy minerals.

3:35 PM

Large Eddy Simulation of Dense Medium Cyclone

R. Rajamani1, K. Bhaskar2 and J. Delgadillo3; 1Metallurgical Eng.,University of Utah, Salt Lake City, UT; 2Advanced Materials andProcess Research Laboratory, Bhopal, India and 3Metallurgical Eng.,University of San Luis Potosí, San Luis Potosí, Mexico

CFD simulation is carried out on a 76mm dense medium cyclone using threedifferent approaches. The first two approaches were aimed towards reducing thecomputational efforts using three fluid phases and the Reynolds Stress Method(RSM) for resolving turbulence. The third stage included a more comprehensive

simulation using five fluid phases and with the Large Eddy Simulation (LES)method for resolving turbulence. The simulated results are compared with thepublished experimental results of a 76mm standard dense medium cyclonedesign fitted with 22.54 mm vortex finder and at 15.0 mm diameter spigot opening.The simulated results of size and density based distribution characteristics of coalparticles generated through discrete phase modeling technique are used forvalidating with the reported experimental results. Though the three phase multi-simulations using RSM turbulence model is less in computational expense, theresults obtained with five phase simulation using LES turbulence model is foundto be accurate in terms of cut density and slope of the distribution curves.

3:53 PM

Sustainability Aspects of Minerals Processing Chemicals

R. Capanema, D. Nagaraj, C. English and P. Bowles; MiningChemicals, Cytec Industries Inc., West Paterson, NJ

Sustainability is a critical topic of discussion today in the mining industry in viewof the significant growth in demand for minerals and metals, shortage of mineraland human resources, stringent regulatory and environmental concerns, andinadequate technological solutions to many of the new challenges. The miningindustry uses a large amount of diverse chemicals which are also subject toincreased scrutiny in terms of environmental fate and footprint. This paper willexplore the toxicity, transportation, environmental, and regulatory aspects of thetraditionally used mining chemicals. Examples of “greener”, sustainablealternatives to these traditional chemicals that provide equivalent or bettermetallurgical performance will also be discussed.

4:11 PM

A Model for the Adsorption of Hydrolysable Cations on Silica

S. Vivek1

, R. Yoon1

and M. Fuerstenau2

;1

Center for AdvancedSeparation Technologies, Virginia Tech, Blacksburg, VA and2University of Nevada-Reno, Reno, NV

An atomic force microscope (AFM) was used to measure the surface forcesbetween silica surfaces immersed in solutions of hydrolysable cations and/orsodium oleate. Hydrophobic forces were observed at the pH range where theconcentration of the singly-charged hydroxo-complexes (CaOH+ or MgOH+) insolution is the highest. In the absence of oleate, the adsorption of the hydroxo-complexes was indicated by the disappearance of the repulsive hydration force.These results indicate that hydrolysable cations adsorb on silica as singly-chargedhydroxo-complexes. Based on the results obtained in the present work, a modelfor the adsorption of hydrolysable cations has been developed.

Somasundaran Symposium: Research, Characterizationand Measurement Systems I


Chair: D. Nagaraj, Cytec Industries Inc, Stamford, CT

2:05 PM

Bentonite-inorganic Interactions and Their Role in Industrial

Applications

M. Celik, F. Boylu, K. Cinku, G. Bulut and B. Benli; Mineral ProcessingEngineering, Istanbul Technical University, Istanbul, Turkey

Bentonite with world annual consumption of 15 million tons is an importantcommercial commodity utilized over 20 different areas. The technologicalproperties such as ion exchange, swelling and high surface area are the majorfeatures that dictate the field of utilization. However, ion exchange by itself is thesingle fundamental tool that leads to a number of commercial applications suchas drilling, foundry, water and solvent based thickeners, nanocompozites, etc. Inthis study, the interaction of major inorganic ions, i.e., Na+, Ca2+ and Mg2+ withthe bentonite matrix is elucidated with the help of data on cation exchangecapacity (CEC), viscosity, swelling, filtration loss and zeta potential. The resultsare analyzed in view of the requirement for respective industrial application.

2:25 PM

Thickener Dynamics and Control

F. Concha1, J. Segovia2 and R. Bürger3; 1Metallurgical Engineering,University of Concepción, Concepcion, Chile; 2Electrical Engineering,University of Concepción, Concepción, Chile and 3MathematicalEngineering, University of Concepción, Concepción, Chile

In this paper we present the process dynamics and control strategies for aconventional thickener. Thickening parameter determination on a copper flotationtailing and a process analysis show that the phenomenological behavior of

43



thickening present strong no-linearity and even gain inversion. This explain whyclassical control strategies fail and operators decide to open control loops. To beable to compare Classical PID Controllers and Multivariable Fuzzy Logic Controllerstrategies, a phenomenological model developed by Concha and Bürger was used.During the analysis the model was subjected to several perturbations such aschange in the feed rate and change in the set point of the under flow.

2:45 PM

Effect of pH and Electrolyte on the Stability of Surfactant-free

Foam Films

R. Yoon1 and L. Wang2; 1Center for Advanced SeparationTechnologies, Virginia Tech, Blacksburg, VA and 2School of

Engineering, University of Queensland, Brisbane, QLD, AustraliaThe stability of surfactant-free foam films was studied using the thin film pressurebalance (TFPB) technique. In pure water, it was not possible to produce foamfilms due to weak film elasticity and strong hydrophobic force. In the presence ofNaCl, however, the hydrophobic force was sufficiently dampened to allowmetastable films to form. At 10-5 M NaCl, the equilibrium film thickness reacheda maximum of approximately 130 nm at pH 6.0-7.3. The thinner films obtained oneither side of this pH range was due to the increased ionic strengths caused bythe HCl and NaOH added to control the pH.

3:05 PM

Automated Mineralogical Study of Ore Domains at Bingham

Canyon, Utah, USA

J. Ross1, K. Hoal2, S. Appleby2 and P. Botha3; 1Department of Geologyand Geological Engineering, Colorado School of Mines, Golden, CO;2

Advanced Mineralogy Research Center, Colorado School of Mines,Golden, CO and 3Intellection Corporation, Westminster, CO

Predicting recovery rates in ore bodies is one of the key factors in miningoperations. Understanding the mineralogy of the deposit is essential as it controlsthe distribution of ore minerals. In order to assess the relationship betweenmineralogy and recovery in greater detail this study integrates optical microscopyand automated mineralogy using QEMSCAN® to characterize the mineralogy ofkey ore domains from the Bingham Canyon Mine. The initial study on 13 handsamples from different domains at the mine focuses on determining the ores’modal mineralogy and sulfide mineral assemblages. In addition, it tests theQEMSCAN® capabilities in measuring parameters such as the distribution offractures and minerals that could impact comminution, and assessing the typeand degree of alteration. Preliminary results of this study show that samplesrepresenting different ore domains vary greatly in fracture abundance and inmineralogy. This demonstrates that integrating automated mineralogy into mineralprocessing procedures is of major importance in improving recovery models. Amore detailed study across several ore domains will correlate JK Drop WeightTests with automated mineralogy.

3:25 PM

A Proposed Model of a New Laboratory Magnetic Separator for

the Mineral Processing Companies

S. Ulla; Ore Dressing, Matrix Metallics, Bangalore, India

A new model of a laboratory magnetic separator has been conceived to cater theneeds of process engineers and mineralogists world over engaged in themineralogical investigations. The proposed model conceptualized after a longresearch in the field of process mineralogy and keeping in view the setbacks ofother separators is a laboratory instrument that could separate and concentratevarious minerals depending upon their magnetic susceptibilities. Based on thebasic concept of isodynamic magnetic separator, the model conceived would notonly speed up the work of a mineralogist, but it would save the energy and havean effective separation. Unlike other separators, it could produce more than tenfractions at a time in a span of three hours. In the present paper, the graphicdesign and detail operation of the separator is being proposed to various mining

companies and research and development sectors for its economic feasibility andfabrication that would have worldwide market. The concept has been patented.

3:45 PM

A Bubble Coalescence Study Using Sound

J. Finch and W. Kracht; Mining and Materials Engineering, McGillUniversity, Montreal, QC, Canada

Frothers are surfactants used in flotation to aid generation of small bubbles.Studying events at the moment of bubble creation is a challenge because of theshort time frame. This presentation introduces a novel acoustic approach. Thetechnique has the resolution capable of detecting events that occur within 1-2 ms.The transition from coalescence to non-colaescence is tracked as a function ofsurfactant concentration and gas rate through the capillary. Results are given forsome common flotation frothers and n-alcohols (C4-C8). A stress model is usedto give a qualitative explanation to the observed action of frothers on coalescenceprevention. Results for salt (sodium chloride) are included for comparison.

4:05 PM

Application of Partition Modeling in the Redesign of a Heavy

Mineral Sands Plant

G. Luttrell1, G. Adel1 and T. McKeon2; 1Mining & Minerals Engineering,Virginia Tech, Blacksburg, VA and 2Dupont Mining, Starke, FL

Partition models are commonly used evaluate processing circuits incorporatinggravity-based separators. Unfortunately, this useful approach has traditionallybeen overlooked by the heavy minerals sands industry due to difficultiesassociated with the use of toxic heavy liquids and accuracy limitations createdby variations in feed par ticle size and shape. In the present study, these problemshave been avoided via the development of partition models based onexperimental data from microscopic grain-counts. This technique, whichessentially uses the different mineral species as density tracers, provides a newtool for modeling the multi-stage circuits that are commonly required tosuccessfully upgrade heavy mineral sands. The partition model approach easilyidentifies shortcomings of existing circuits and, when used with conjunction withlinear circuit analysis, provides tremendous insight regarding the optimumarrangement of unit operations in terms of separation efficiency and plantthroughput capacity. An industrial case involving the redesign of a heavy mineralsand spiral plant is presented to demonstrate the full capabilities of this approachfor plant optimization.

4:25 PM

Characterization of Frothers and its Role in Flotation

Optimization

F. Cappuccitti1, J. Finch2, J. Nesset2 and W. Zhang2; 1Flottec, LLC,Boonton, NJ and 2McGill University, Montreal, QC, Canada

Significant progress has been made over the past few years in understanding thedual role of frother in controlling bubble size in the pulp and properties of the froth.Using recently developed measurement techniques, studies have shown thatfrothers can be classified into families, each with their own unique relationshipbetween bubble size reduction, gas hold up, water recovery and froth stability.This makes for a complex relationship that many operators feel uncomfortabletrying to optimize. This is seen as unfortunate since frother plays a large role indetermining both the grade and recovery of mineral values. This paper describesa procedure to characterize frothers and how this information can be used toselect a frother. Examples from plant experience will be discussed.

UCA of SME: Tunnel Ventilation


Chair: B. Bohlke, Myers Bohlke Enterprise, LLC, Great Falls, VA

2:05 PM

Application of CFD in Analysis of Jet Fans for Emergency Tunnel

Ventilation

N. Shahcheraghi; Tunnel Ventilation Group, Earth Tech, Oakland, CA

Use of jet fans in emergency tunnel ventilation has become more popular in theUS over the past years parallel to reduced cost of computational power. Therfore,it is inevitable that more sophisticated computational analysis are used in theanalysis of jet fan performance in fire emergency conditions. CFD is the analysistool, which has become an integral part of modern emergency tunnel ventilationanalysis. Specifically, CFD analysis is used to capture the three dimensionaltemperature stratification patterns in the ventilation flow past a tunnel fire. Thesethree dimensional temperature stratification patterns are used to refine the onedimensional temperature profile along the tunnel as predicted by SES. The

improved temperature predictions allow for a more accurate analysis of the jetfan performance during fire emergency conditions.

2:25 PM

Differences in Design Considerations for Tunnel vs. Mine

Ventilation Fans Systems

G. Gamble1 and R. Ray, Jr.2; 1Clarage, A Twin City Fan Company,Akron, OH and 2PB Americas, Inc., New York, NY

Fans used to ventilate subway, passenger rail and roadway tunnels are similar tothe fans used to ventilate underground mines. However, tunnel ventilation fansystems are typically designed to meet NFPA 130 or 502 standards, while mineventilation fan systems must comply with the appropriate federal mine safetyregulations. As a result, fan operation requirements and performance criteria, aswell as typical fan and duct configurations differ significantly for tunnel and mineventilation applications. Variations in environmental conditions in tunnels ascompared to mines also results in differences in fan performance and material

44







9:51 AM

Potential Benefits of Waterjet Scaling in Rapid Tunneling

Systems

M. Kuchta and H. Miller; Mining Engineering, Colorado School ofMines, Golden, CO

Tests conducted at the Colorado School of Mines Edgar Mine showed waterjetscaling to be viable scaling technique for removing loose rocks in mine openings.The test program consisted of five slash rounds blasted using conventionalcharging for perimeter holes and five rounds blasted using smoothwall techniques.Smoothwall blasting produced a significantly smoother drift contour and resultedin significantly less scaled material. The generally smooth drift contour producedby smoothwall blasting reduces the chances of large blocky material being formedand thus improves the performance of the waterjet scaling system. The integrityof the drift walls can be improved with subsequent shotcrete application. Previoustests also showed that shotcrete adhesion improves significantly on surfacescleaned with a waterjet compared to the normal method of surface preparation.It is believed that the use of waterjet scaling could reduce the overall cost andcycle time in drill and blast tunneling operations. This paper will review the resultsof previous waterjet scaling tests and discuss the potential benefits of waterjetscaling in an integrated drill and blast tunneling system.

10:10 AM

Results and experience from a joint project on Faster and Better

Development at the LKAB mine in Malmberget

G. Bäckblom; Managing Director, Rock Tech Centre AB, Gällivare,Sweden

Tunnelling/drifting is a costly activity in infrastructure projects as well as in mining.

Improvements in safety and advance rates were considerable until the 1980s.Since then equipment in Sweden has not yielded significant increase in advancerates, quality, or cost reduction. There is a need to generate positive cash flowfrom a start-up mine. For this purpose, rapid advance is more important than cost-cutting in the drifting process. Many mining companies, implementers of finaldisposal of spent nuclear fuel, contractors and equipment suppliers joined forcesin 2006 to improve underground development work. The focus of the main projectis to analyse the effects of improved quality on advance rate and costs. A baselinewas developed at the LKAB mine at Malmberget to suggest short-termimprovements. Improvements were implemented and the results were comparedwith the baseline. One important conclusion from the work is the need for step-changes in the approach to ground support. RTC initiated a Mining Initiative onDevelopment of Ground Support Systems and Equipment where several majormining companies in Canada, Poland and Finland joined forces with majorequipment suppliers.

Coal & Energy/UVC: Ventilation I

9:00 AM • Tuesday, February 24

Chairs: I. Loomis, Freeport McMoRan, Baton Rouge, LA

B.Prosser, MVS Enginnering, Fresno, CA

9:05 AM

Impact of Air Velocity and Support Advance on Shield Generated

Dust

G. Chekan, J. Ryder, J. Colinet and J. Listak; NIOSH, Pittsburgh, PA

Steady increases in longwall production have required operators to apply greaterquantities of ventilating air in an effort to control and dilute respirable dust. Inconjunction, as shearer speeds increase this necessitates that longwall suppor tsalso be advanced at a faster rate. This contributes to overall respirable dust levelson the longwall face because as supports are lowered and advanced, brokenmaterial falling from the top of the canopy is entrained directly into the air stream.The Pittsburgh Research Laboratory of NIOSH collected respirable dust samplesfrom four longwall faces to characterize shield generated dust. This paper detailsrespirable dust generation as a result of two main operational parametersassociated with shield dust: face air velocity and rate of shield advance. The paperalso discusses the effectiveness of engineering controls currently used to reduceshield dust and alternative controls being investigated by NIOSH.

9:25 AM

Safe Practices for Installing Booster Fans in Underground Mines

F. Calizaya; Mining, U of Utah, Salt Lake City, UT

The objective of this study is to provide potential users of booster fan systemswith the necessary information on the installation, commissioning and operationof main underground booster fans. The safe practices described in this paper

47

Tuesday, February 24 Morning

GAUDIN LECTURE


Lecturer: Raj K. Rajamani

University of Utah

Mining & Exploration: Underground Mining Operations:

Controlled Blasting and Rapid Excavation: International


Chairs: W. Hustrulid, NIOSH, Spokane, WA

C. Dreesbach, Montana DEQ, Helena, MT

8:35 AM

Rapid Construction - A Key to Success in Mining

A. Moss; Rio Tinto Copper Group, Vancouver, BC, Canada

A number of very large scale underground mines are in various stages ofdevelopment. A common characteristic is the need for many kilometers ofdevelopment drifting prior to production start. Even a small increase in the driftingrate can have enormous economic consequences. The Rio Tinto program toincrease development rates is discussed.

8:54 AM

Norwegian High-Speed Tunneling Experience

F. Nilsen; Leonhard Nilsen & Sønner As (LNS), Norway, Norway

Improved access, reduced transport distance for coal, and increased safety risksdue to water were the main arguments when Store Norske SpitsbergenGrubekompani As (SNSG) in 2002 decided to build a new access to the SveaNord coal mine. The existing access was built on the Høganes Glacier, ending at330 masl. The road had a bold alignment and put great demands to the truckdrivers. Several alternatives were investigated before deciding to build a tunnelbegining from sea level to the lowest point of the mine at 285 masl. The tunnel has

a cross section area of 38.5 m2 and a length of 5630 m. The tunnel contains theconveyor for transporting the coal from the mine to the surface, and it is also usedfor mine ventilation purposes. The tunnel was awarded as a turnkey project toLeonhard Nilsen & Sønner As. The work with the pre-cut star ted in July 2002 andthe tunnel excavation started in November the same year. The hole through tothe mine was blasted on December 3, 2003. The average performance was 103.3m/week and the best week resulted in 150.1 m of tunnel. The averageperformance in the permafrost zone was 56.5 m/week while it was 108.5 m/weekoutside the frost zone.

9:13 AM

New Experiences in Rapid Development

E. Tanner; Business Line Manager - URE, Atlas Copco CMT USA,Commerce City, CO

Rapid development is a key to successful large-scale underground miningoperations. The paper describes the application of modern drilling tools toachieving very high advance rates.

9:32 AM

Desktop Study of Rapid Development in Mining

G. Swan; XSTRATA, Onaping, ON, Canada

At the 2007 SME meeting in Denver, XSTRATA Nickel presented the technicalbasis for rapid development using drill and blast techniques. This paper presentsan update of the XSTRATA rapid development program



were compiled from actual installations, reviewed for completeness and evaluatedagainst U.S. and international standards. The principles involved in the designand installation of these fans as well as the provisions needed to guarantee thesafe operation of these units, are illustrated by four samples cases. These casesare also used to illustrate some key design parameters and operating practices,which if not considered may results in system inefficiencies of fan failures. Thestudy concludes with a summary of basic design requirements and factors thatmust be evaluated for the safe operation of the whole vent system.

9:45 AM

Investigation into the Practical Use of Belt Air at US Longwall

Operations

R. Krog1 and C. Bise2; 1NIOSH, Pittsburgh, PA and 2College ofEngineering and Mineral Resources, West Virginia University,Morgantown, WV

The use of belt air as an intake source at longwall operations has changed overthe past decades. This paper will investigate the previous and current ventilationpractice regarding the use of belt air during gateroad development and longwallpanel extraction. A ventilation history and review of current ventilation practiceswill be covered. Operating considerations regarding air quantities and pressuresto deliver the required airflow will be investigated using network solutions. Thepractical considerations for the use of belt air which are controlled by a variety offactors including: airflow quantity and velocity, coal methane content, methanedesorption rates, coal mining rate, belt length, leakage, and number of gateroadentries. At longwall operations, the advantages and disadvantages of belt air aredifferent for gateroad development and for panel extraction. During gateroaddevelopment, the use of belt air on intake eliminates a possible leakage path(intake to belt return) and increases the quantity of air reaching the last opencross cut given the same amount of pressure and flow available at the mains.

10:05 AM

Coal Mine Ventilation Efficiency: a Comparison of US Coal Mine

Ventilation Systems

C. Hairfield; Marshall Miller & Associates, Ashland, VA

With ever rising energy costs, it is increasingly important for mines to operate withenergy efficiency. As a large portion of a mine’s energy consumption is oftenattributed to the operation of mine ventilation fans, maintaining an efficientventilation system is a critical pro-active way for mining companies to reducepower costs. A common way to measure a mine’s ventilation system efficiency isto calculate the volumetric efficiency, which is simply a calculation of thepercentage of total mine air that is usefully employed for production. The purposeof this study is to document a nationwide comparison of the volumetric efficiencyof a multitude of U.S. underground coal mining operations. The results will aim toshow just how efficient today’s coal mine ventilation systems are and what factorsmay be causing the efficiencies and inefficiencies.

10:25 AM

Simulation of Methane Distribution Under Normal and Outburst

Conditions at Longwall Faces

D. Zheng2 and J. Tien1; 1Mining and Nuclear Engineering Department,Missouri University of Science and Technology, Rolla, MO and2Mining and Nuclear Engineering Department, Missouri University ofScience and Technology, Rolla, MO

Under normal circumstances, methane released along a longwall face representsonly 10%~20% of the total methane emitted from the entire longwall panel.However, there might be a sudden surge of methane at the face which can causea problem because the friction from shearer cutting, support movement, andscraper conveyor dragging can be ready ignition sources. Therefore, to predictthe distribution of methane will be critical to prevent any dangers. In this paper,methane dispersion patterns along a lognwall face are simulated under normal

and outburst conditions. With the simulation of methane released from the face,around shearer drum, and from the broken coal on the conveyor, places withpossible high methane content are detected by different phases of workingprocess and shearer positions. Local ventilation measures are evaluated soprecautionary measures can be plan ahead.

10:45 AM

CFD Study on Hot Spot Location In Longwall Gob

S. Lolon and F. Calizaya; Mining Engineering, University of Utah, SaltLake City, UT

Spontaneous combustion is one of the main sources of fires in underground coalmines. Most of these fires are initiated in caved area (gob). A study was carriedout to identify the location of these spots. The study is based on mine ventilationsurveys, laboratory experiments, and Computational Fluid Dynamics (CFD)simulations. Four CFD models were formulated and solved: three utilized ableeder ventilation system, and the fourth a bleederless system. For each model,

the gob was divided into three zones of different permeability: unconsolidated,semiconsolidated, and consolidated. The simulation results showed that in amodel ventilated by a bleeder system, the hot spot was located in the consolidatedzone near the return side of the gob. It propagated along the tailgate side as thegob progressed. In the model ventilated by a bleederless system, the hot spotwas located by the face line. The leakage flow through the gob played animportant role in determining the size and location of the hot spot.The studyconcludes with a set of ventilation schemes and recommendation to reduce thedevelopment of hot spots.

11:05 AM

Case Study of Diesel Particulate Matter (DPM) Control by Mine

Ventilation Improvement for an Underground Metal Mine

H. Wang; Newmont Mining Co., Elko, NV

Effective may 2008, new regulation on DPM by MSHA requires that a miner’spersonal exposure to DPM must not exceed 160 microgram of total carbon percubic meter of air. There have been many discussion and research on dieselparticulate matter control technologies which include using MSHA approvedengines, Engine filters, bio-diesel and higher ventilation rates. A case study at anunderground gold mine indicated that improve ventilation efficiency at both theworking face and haul road might be one of the most effective ways to reduce theDPM exposure.

Coal & Energy: Alternative Fuels


Chair: T. Yegulalp, Columbia University, New York, NY

9:05 AM

Pre-Combustion Capture of CO2 from Coal Gasification Gases:

Case of CaO on γ -Al2O3

A. Belova and T. Yegulalp; Earth and Environmental Engineering,Columbia University, New York, NY

Conversion of coal into high-value gases via gasification offers significant pollutionreduction and efficiency improvement benefits associated with controlledcombustion of clean gases for power generation. However, current gasificationbased electricity production technologies, such IGCC, while efficient and cleanwhen compared to traditional coal power plants, do not address carbon dioxideemission. The project focuses on CO2 capture on CaO; where to overcome kineticand stability limitations associated with its utilization, CaO is distributed on high-surface area γ -Al2O3 and supported on a ceramic honey-comb monolith. The

proposed method allows for efficient capture of CO2 from a gas mixture, asstudied on a flow-through reactor system. This novel method of CO2 capture isused here to argue for pre-combustion capture of CO2 in coal gasification-basedpower plants. When CaO is present during the steam reforming of coalgasification gases, continuous withdrawal of CO2 from the system provides forhigher yields of reforming products (hydrogen gas) by influencing thethermodynamic equilibrium of the entire system.

9:25 AM

The Benefits and Challenges of Biofuels

D. Zilberman; Agriucltural and Resource Economics, University ofCalifornia Berkeley, Berkeley, CA

Fuels from crops and their residue are becoming an important source of liquidfuels for transport. Ethanol produce d mostly from maize and sugar canecontribute to up to 5% reduction in fuel prices in 2007 but also contributed up to20% increase in the price of corn. Expansion of biofuel acreage will lead to asignificant impact on food prices, and will encounter political resistance unlessfood and fuel productivity is increasing. Polices will need to enhance research todevelop second more productive generation of cellulosic biofuels and lightenregulations to allow better utilization of Biotechnologies in food production. It isimportant to introduce mechanisms to assure food security as biofuels areas areexpanded. Incentive to encourage biofuel with positive effects on Green housegases need also to be introduced.

9:45 AM

Experimental Investigation of CH4 Production from Methane

Hydrate

Y. Zhou, M. Castaldi and T. Yegulalp; Columbia University,New York, NY

Natural gas hydrates have the potential to meet global energy needs for theforeseeable future. The total amount of carbon entrapped in hydrates is estimated

48



to be more than twice the known fossil fuel carbon content. To test the concept ofmethane production via in-situ heating and characterize other alternativeproduction schemes, a custom made novel reactor vessel has been designed,fabricated and assembled. Preliminary tests show that the reactor satisfies theconditions for methane hydrate and carbon dioxide formation. Thermocouples inthe reactor detected the temperature change associated with methane hydrateformation. Hydrate was formed at 2.2 oC and about 600 psi with a concentrationof 99.97% pure methane gas and DI water. Based on mass balance calculation,4.45% volume of sediment was occupied by hydrate. Measurements andsimulations suggest that hydrate was initially formed at the top section of thereactor followed by the hydrate formation within the sediment. During thedissociation via depressurization experiment, a cooling effect caused by theendothermic dissociation reaction was observed.

10:05 AM

Changing the Hydrate Energy Paradigm from Assessment to

Production

D. Sloan, C. Koh and A. Sum; Colorado School of Mines, Golden, CO

This work summarizes world progress with respect to making energy productionfrom hydrates a reality. In particular progress is reported regarding (a) permafrosthydrate production testing, (b) marine hydrate viability assessment (c) climateeffect of hydrates, and (d) international collaboration.

10:25 AM

Pre-Combustion Capture of CO2 from Coal Gasification Gases:

Case of CaO on γ -Al2O3

A. Belova, T. Yegulalp and M. Castaldi; Columbia University,New York, NY

Conversion of coal into high-value gases via gasification offers significant pollutionreduction and efficiency improvement benefits associated with controlledcombustion of clean gases for power generation. However, current gasification-based electricity production technologies, such as IGCC do not address carbondioxide emissions. The focus of the study is CO2 capture of CO2 prior tocombustion of coal-derived gases. To overcome kinetic and stability limitationsassociated with its utilization, CaO is distributed on high-surface area γ -Al2O3and supported on a ceramic honey-comb monolith. The proposed method allowsfor efficient capture of CO2 from a gas mixture, as studied in a flow-throughreactor system. This novel method of CO2 capture is used here to argue for pre-combustion capture of CO2 in coal gasification-based power plants. When CaOis present during the steam reforming of coal gasification gases, continuouswithdrawal of CO2 from the system provides for higher yields of reformingproducts (hydrogen gas) by influencing the thermodynamic equilibrium of theentire system.

Coal & Energy: Research & Development


Chair: T. Camm, NIOSH, Spokane, WA9:05 AM

MineTracer Wireless Mesh Communications and Tracking

J. Barrett; Venture Design Services, Liberty Lake, WA

State-of-the-art wireless communication and location-tracking technologies willdramatically change the face of mine worker safety. The MineTracer Systemdeveloped by a Liberty Lake Washington company is a broad capability wirelesssensor network based on a new breed of technologies known as wireless meshsystems. In this paper, R&D Manager Jim Barrett summarizes the balance ofengineering tradeoffs that result in a system that (1) performs well, (2) is

survivable against many types of mine accidents, (3) operates for many hourspost-accident on battery power, (4) meets stringent MSHA requirements forintrinsic safety, and (5) is economically affordable for the mines.

9:25 AM

Techniques to Investigate Subsidence Events over Inactive

Room-and-Pillar Mines

Y. Luo; Mining Engineering, West Virginia University,Morgantown, WV

Uncertainty often arises in investigating structural damage claims over inactiveroom and pillar (R&P) coal mines. Disputes are often focused on whether thestructural damages are resulted from mine subsidence or from other causes. R&Pcoal mines without pillar extraction are carefully designed not to cause surfacesubsidence. Subsidence do occur in some rare cases. Such unexpectedsubsidence events likely occur over sealed sections or abandoned mines. The

unexpected nature and often rapid progression of subsidence over inactive R&Pmines make it difficult to investigate. Successful investigation depends mainly on:quick response to quantify the remaining process, pattern recognition of thedistributions, and identification of the potential root causes. Techniques used ininvestigating a number of subsidence claims over inactive R&P mines arepresented. The analysis showed that mine subsidence did not play any role insome of the claims while it was apparently responsible in other cases. Among thetrue subsidence cases, water and soft rock in the immediate roof or floor of themined coal seams appeared to be the main root causes for the unexpectedsubsidence events.

9:45 AM

QEMSCAN: - A New Tool for the Characterisation of Coal and

Mineral MatterD. French1, A. Butcher2 and J. van Zyl3; 1Energy Technology, CSIRO,Bangor, NSW, Australia; 2Intellection Pty. Ltd., Brisbane, QLD,Australia and 3Intellection Pty. Ltd., Brisbane, QLD, Australia

In order to improve the efficiency of coal utilisation and reduce the environmentalfootprint there is a need within the coal industry to better characterise coal andcoal utilisation by-products. QEMSCAN combines Scanning Electron Microscopywith Energy-dispersive X-Ray analysis to automatically measure samplecharacteristics such as mineralogy, particle size distribution, morphology andmineral association. This new method of phase-specific analysis is a powerful toolfor coal characterisation as it provides unique quantitative mineralogical, textural,and chemical data on a particle-by-particle basis, for both coal and mineral matter.QEMSCAN automatically identifies most common ash-forming minerals on-lineand then creates digital particle images. These images contain information onparticle shape, area and size and modal composition, together with grain sizeestimates, associations, and chemical composition, all of which can be extractedfrom the images using Intellection’s iDiscover software, and quantified on aparticle-by-particle, size-by-size basis. The analytical procedure will be describedand examples of the types of quantitative output discussed.

10:05 AM

How Does Limestone Rock Dust Prevent Coal Dust Explosions

in Coal Mines?

C. Man and K. Teacoach; Disaster Prevention and Response Branch,NIOSH, Pittsburgh, PA

Explosions involving fine coal particles are usually very violent and destructive.Therefore, abundant ventilation in all unsealed areas of a mine is important as thefirst line of defense against an accidental explosion. In addition to this, generousapplications of pulverized rock dust can prevent the propagation of coal dustexplosions. During an explosion the rock dust disperses, mixes with the fine coaldust and prevents flame propagation by acting as a thermal inhibitor or heat sinki.e. the rock dust reduces the flame temperature to the point where devolatilization

of the coal particles can no longer occur; thus, the explosion is inhibited. A numberof explosions using various coal dust and limestone rock dust mixes have beencarried out at the NIOSH Lake Lynn experimental mine. A consistent set of post-explosion floor dust samples were taken along the entry after each test. Thesewere analysed in the laboratory to determine how the limestone rock dustbehaved during the coal dust / rock dust explosions. Preliminary results indicatethat the chemistry of limestone plays an important role in its significant capacityto inhibit coal dust explosions effectively.

10:25 AM

Study on the Effects of Circulating Pulp on Separation

Performance of FCSMC

X. Zhou1 and J. Liu2; 1Dept. of Mining Engineering, University ofKentucky, Lexington, KY and 2School of Chemical Engineering andTechnology, China University of Mining and Technology, Xuzhou,China

A novel flotation device, cyclonic static micro-bubble column flotation, FCSMC,was introduced in this paper. The use of circulating pulp is an important featureof the FCSMC. For this particular column flotation system, the effects of circulatingpulp on circulating pulp pressure, the gas aspiration rate and the flow field wereinvestigated in this study. The relationship between the volumetric flow rate ofcirculating pulp and the number of separation cycles was investigated. The resultsindicate that the gas aspiration rate and the pressure of circulating pulp increasewith increasing circulating pulp rate as well as intensity of cyclonic field. It hasbeen found that the flow rate of circulating pulp should meet the requirementsfrom cyclonic field intensity, circulating separation cycles and the gas aspirationrate as well. The circulating pulp flow rate should be 2~3 times of that of thefeeding pulp. Key words: column flotation; cyclonic field; circulating pulp.

49



Construction Materials & Aggregates:Resource Development


Chair: G.Stevens, Civil & Environmental Consultants, Inc,

Downers Grove, IL

9:05 AM

A Brief History of Aggregate Development in the Denver,

Colorado Area

W. Langer; US Geological Survey, Denver, CO

At the start of the 20th century Denver’s population was 203,795. Most streetswere unpaved. Buildings were constructed of wood frame or masonry. Transportwas by horse-drawn-wagon or rail. Statewide, aggregate consumption was lessthan 0.25 metric tons per person per year. One hundred years later Denver hada population of 2,365,345. Today Denver is a major metropolitan area at thecrossroads of two interstates, home to a new international airport, and in theprocess of expanding its light rail transit system. The skyline is punctuated withskyscrapers. The urban center is surrounded with edge cities. These changesrequired huge amounts of aggregate. Statewide, aggregate consumptionincreased 50 fold to over 13 metric tons per person per year. Denver has a largepotential supply of aggregate, but sand and gravel quality decreases downstreamfrom the mountain front and potential sources of crushed stone occur in areasprized for their scenic beauty. These issues, along with urban encroachment andcitizen opposition, have complicated aggregate development and have paved anew path for future aggregate development including sustainable resourcemanagement and reclamation techniques.

9:25 AM

Current Reclamation Requirements for the Arizona Aggregate

Industry

E. Lips; Brown and Caldwell, Phoenix, AZ

Recently, reclamation requirements for aggregate mining on private land inArizona have changed dramatically. This paper discusses how and why thesereclamation regulations have changed and summarizes the current reclamationrequirements for the Arizona aggregate industry. Prior to 2005, aggregate miningon private land was not subject to any state-wide reclamation requirements.Although reclamation planning has always been part of aggregate mining onpublic lands, a number of city and county guidelines for reclamation on privateland began appearing as part of other permitting processes or anti-mininginitiatives. To provide a standardized state-wide reclamation planning process forthe industry and block local anti-mining legislation, Arizona Rock Product

Association and the Arizona State Mine Inspector sponsored aggregate minedland reclamation legislation. In 2005, the Arizona State Legislature enacted SB1393 requiring approved reclamation plans for aggregate mining on private land.The resulting Statute requires reclamation plans that identify post-mining landuses, provide safe and stable conditions, and provide financial assurance toensure implementation of the plans.

9:45 AM

Multi-Disciplinary Approach to Aggregate Resource Evaluation

J. Light; Granite Construction Inc., Sacramento, CA

Today’s aggregate mining industry has seen dramatic increases in costs relativeto property acquisition, permitting, mining, plant equipment and plant processing.Whether you are evaluating a greenfield resource oppor tunity or re-evaluating aproducing reserve, it is important to incorporate disciplines of geology, materialtesting, mine design, plant design, and mine planning into the feasibility study oroperation modification plan to help control those costs. We present a case study

where an integrated approach was used to better define potential mining areasin an alluvial deposit. We used surface mapping, exploratory boreholes, andgradation data to develop a geologic model that extrapolates material qualitiesand waste percentages throughout the deposit. We determined economic cutoffgrades for percent sand. First, the model determined areas that exceeded thecutoff grade and would be non-profitable. Second, the internal variability of pit rungradation is used to suggest mining methods and blending strategies that mightextend the reserve life. Finally, all of this information is rolled up into a functionalmine plan.

10:05 AM

Mining’s New Sinkhole - Lack of People - Lack of Talent What are

YOU Going To Do About It - Some Solutions

L. Lien; Global Staffing Network, Novato, CA

Mining will expand over 50% in the next five years. New mines are being opened.Closed mines are being re-opened, and every mine is being expanded. Duringthis same period, the industry will lose at least 50% of its professionals thoughretirement and death. In essence, the industry will have to recruit its currentworkforce in the next 5 years. And from where, one might ask? Not from theUniversities. Graduation from mining schools is the lowest it has been in the last20 years. It will specifically address solutions that can be taken by individualmining companies to mitigate the dangers of not enough “good” people. The paper

will outline how companies can avoid the salary spiral for qualified professionals,and maintain a stable workforce. These solutions will require more than a renewed“recruiting” and human resource” effort. Mining companies will have to expand itssources of recruiting, engage in a more effective training and development effort,re-structure salaries and compensation. Those that perform effectively will getand keep the right people. Those that do not will suffer.

10:25 AM

Co-Development of Aggregate Resources on a Multiuse

Commercial Property

G. Stevens; Enviromental and Mining Services, Civil & EnvironmentalConsultants, Inc, Downers Grove, IL

The development of aggregate mines within urban environments may requiremultiuses of a property to sucessfully utilize all of the resources the propertieshave to offer.

Environmental: Environmental Management Systems,United States I


Chairs: R. Miller, MWH Americas Inc, Phoenix, AZ

D.Turner, ADEQ, Phoenix, AZ

9:05 AM

EMS Implementation Guideline for the Hard Rock Mining

Industry

P. Kunkel; Freeport McMoRan, Phoenix, AZ

How effective is your EMS? Concerns from EPA regarding current EMSs’ abilitiesto keep hard rock mining facilities off of the National Priorities List (Superfund)was the driver to for hard rock companies to work together to develop a guidelinefor EMS implementation that focuses on being effective in managingenvironmental risks, regulatory compliance, and environmental footprint. Theguideline is designed for mining operations that are just starting to formalize theirEMS and operations interested in making their EMS more effective. This paper willreport on the process of developing the guideline, stakeholder involvement, anoverview of the guideline, and plans to communicate/train to the guideline.

9:25 AM

Environmental Management Systems and Sustainability in

Mining

K. Parameswaran; Environmental Affairs, ASARCO LLC, Tucson, AZ

ASARCO LLC (“Asarco”) implemented an Environmental Management System(“EMS”) as part of a Consent Decree addressing compliance issues at its facilities.Asarco developed its EMS because of its belief that environmental managementwas an integral part of business management and that environmentalconsiderations needed to be integrated into its day-to-day business managementdecisions. Asarco’s EMS was modeled on the ISO 14001 framework, with anincreased emphasis on ensuring compliance with all its environmental obligations.This paper describes Asarco’s experience with the development andimplementation of its EMS and examines how such systems can contribute tosustainable mining practices.

50

SME & CMA — Together Again in Denver!





10:05 AM

Determining Bulk Mineralogy Using a Modified Modan Approach

on the Questa Rock Pile Materials, New Mexico

V. McLemore1, D. Sweeney1, N. Dunbar1, L. Heizler1 and E. PhillipsWriter2; 1NM Bureau of Geology and Mineral Resources, NM Inst. ofMining and Tech, Socorro, NM and 2University, Black Hills StateUniversity, Spearfish, SD

Petrographic analysis of rocks is traditionally performed using optical microscopypoint counting on thin section. However, this does not provide accurate mineralproportions for sedimentary, volcanic, and soil-like material, because rockfragments, groundmass, and matrix are not identified as specific minerals. In

addition, groundmass phases in volcanic rocks can be too fine to identify, andmaking thin sections of intact soil-like material is difficult because of poorcementation. ModAn is a normative calculation that estimates the proportions ofminerals in a sample “…by applying Gaussian elimination and multiple linearregression techniques to simultaneous mass balance equations” (Paktunc, 2001).This is done by using an integrated combination of bulk rock geochemistry,petrographic observations, clay mineral analysis and site-specific mineralcompositions determined by electron microprobe. One of the features of ModAnthat makes it appropriate for this study is that it can model several sulfide minerals.The mineralogical results determined by ModAn for Questa samples arereproducibly, geologically reasonable, and agree closely with results from ReitveldXRD analysis.

10:25 AM

The Effect of Weathering on Particle Shape and Rock Pile

Stability

S. Nunoo, V. McLemore and A. Fakhimi; New Mexico Tech,Socorro, NM

Research studies have shown that the shape of particles has a significant effecton the shear strength and deformational characteristics of granular materials.Increase in the proportion of coarse material in an otherwise fine-grained granularsoil results in an increase in friction angle. Weathering can change the grain shapeas well, more weathered sands tend to be rounder regardless of particle size.Particle shape analysis was performed on samples collected from the Questamine rock piles, the debris flow and the pit alteration scar. In order to increasethe validity of the particle shape analysis, 4 persons including 2 geologists and 2mining engineers were involved in describing the particle shapes. The results ofthis analysis indicate that rock fragments at Questa Mine are mainly subangular,subdiscoidal and subprismoidal. The sphericity and angularity of the rockfragments of the older analogs are similar to those of the younger rock piles. Thissuggests that short-term weathering (100 years) and longer hydrothermalalteration has not noticeably changed the particle shapes at the test locations.

11:05 AM

Effects of Weathering and Alteration on Point Load and Slake

Durability Indices of the Questa Rock Piles, New Mexico

G. Ayakwah1, V. McLemore2, A. Fakhimi3 and V. Viterbo4; 1MineralEngineering, New Mexico Tech, Socorro, NM; 2Mineral Engineering,New Mexico Tech, Socorro, NM; 3Mineral Engineering, New MexicoTech, Socorro, NM and 4Freeport – McMoran Copper and GoldMorenci Operations, Morenci, AZ

Point load strength (Is50) and slake durability (ID2) indices provide a measure ofthe strength and durability of rock fragments and are related to the alterationintensity and frictional resistance of the materials. Samples were collected fromthe rock piles, alteration scars and the debris flow at the Questa mine with thepurpose of examining relationships between Is50 and ID2, mineralogy, chemistry,geotechnical parameters, weathering, and alteration. The Is50 from the variousrock piles ranges from 0.6-8.2 MPa and the ID2 ranges from 80.9-99.5%. TheIs50 and ID2 results indicate that the samples from the debris flows are slightly

stronger (average Is50=4.0 MPa and ID2=98.4%) than the rock pile samples andthat the alteration scar samples are slightly weaker (average Is50=2.8 MPa andID2=89.3%) than the rock pile samples, but still most of these rocks are strong interms of their Is50 and ID2. The Is50 decreases as the degree of weatheringincreases in some rock pile and alteration scar samples, but not all. However,after 40 years of weathering, the majority of the rock fragments within the rockpiles still indicate high strength.

11:25 AM

The Effect of Weathering on Particle Shape of Questa

Mine Material

S. Nunoo, V. McLemore and A. Fakhimi; New Mexico Tech,Socorro, NM

Research studies have shown that the shape of particles has a significant effecton the shear strength and deformational characteristics of granular materials..

Weathering can change the grain shape as well, more weathered sands tend tobe rounder regardless of particle size. Particle shape analysis was performed onsamples collected from the Questa mine rock piles, the debris flow and the pitalteration scar. In order to increase the validity of the particle shape analysis, 4personnel were involved in describing the particle shapes to avoid errorencountered by Folks, 1955. The results of this analysis indicate that rockfragments at Questa Mine are mainly subangular, subdiscoidal and subprismoidal.The sphericity and angularity of the rock fragments of the older analogs are similarto those of the younger rock piles. This suggests that short-term weathering (100years) and longer hydrothermal alteration has not noticeably changed the particleshapes at the test locations. Rock piles made of more angular particles are morestable compared to rock piles with rounded par ticles.

11:25 AM

A Standard Column Weathering Test to Estimate Coal

Overburden Leachate Quality

E. Perry1, R. Hornberger3, K. Brady2 and J. Cuddeback4; 1USDI Officeof Surface Mining, Pittsburgh, PA; 2Pennsylvania Dept EnvironmentalProtection, Harrisburg, PA; 3Pennsylvania Dept EnvironmentalProtection, Pottsville, PA and 4Computer Sciences Corporation,Alexandria, VA

Simulated weathering analyses of coal overburden lack a consistent test protocol.A three phase project developed a reproducible column technique. It includes acontrolled particle size composition, weekly leaching events, and a six dayaeration cycle with humidified air containing 10% CO2, for 14 weeks. Phases I andII developed and refined the protocol. In phase III, five rocks with a range of pyriteand carbonate content were analyzed in an inter-laboratory study. Specificconductance, pH, Ca, Mg and sulfate were the most reproducible parameters.Metals leached at low concentrations had the largest relative percent difference.

The test produced leachate quality consistent with mineralogical and Acid BaseAccounting interpretation. The US EPA is reviewing results for designation as EPAmethod 1627 Kinetic Test Procedure for the Prediction of Acid Mine DrainageQuality. The Kinetic Test Procedure provides a consistent protocol for estimatingmine water quality of coal overburden or other pyritic rocks. It is useful for sampleswhose behavior is difficult to interpret from static test data alone.

Geology: Geotechnical Engineering and Mine Design I


Chair: R. Pratt, Call & Nicholas, Inc., Tucson, AZ

9:05 AM

A Holistic Assessment of Slope Stability Analysis in Mining

Applications

K. Sinha and K. Sample; Vector Engineering, Inc., Grass Valley, CA

Slope stability analysis is an integral part of various mining applications includingdesign of waste dumps, heap leach piles, solution ponds, and tailings dams.Generally, limit equilibrium analysis using one of the several prevalent approachesis considered adequate. In earthquake-prone regions, the seismic forces aremodeled as inertia forces in a pseudo-static analysis. The density, saturation, andshear strength parameters of the materials forming the slope affect the failuremode and the calculated factor of safety. These parameters are generally basedon laboratory tests. Field practices and construction procedures are often notcompletely simulated in the laboratory for various reasons. This paper presentsa holistic assessment of slope stability analysis practice. A sensitivity analysis isconsidered to demonstrate the effects of various factors and procedures cominginto play. Finally, a simple, cradle-to-grave-type approach is used to build somerealistic scenarios of sampling, laboratory procedures, construction procedures,field conditions, resulting variation in design parameters, etc., and their combined

impact on factor of safety is examined.

9:25 AM

An Emerging Groundwater Mapping Procedure for Use

in Mine Design

P. Rollins; Willowstick Technologies, Las Vegas, NV

This paper examines both the theoretical basis and the practical implications ofa minimally invasive groundwater mapping method as applied to mine design.The data acquired through this method sustains both two-dimensional maps andthree-dimensional models of the local groundwater system, thus providing crucialinformation for pre-mining surveys and tailings system design. The methodinvolves inducing a low voltage, low amperage, high frequency audio electricalcurrent into the groundwater system. This current naturally gathers in areas ofhighest conductivity—which include regions of both relatively high watersaturation and relatively high levels of Total Dissolved Solids (TDS). Per the Biot-Savart law—which relates magnetic fields to their source currents—this current

52



emits a magnetic field that reveals vital information about the location, characterand preferential flow paths of the groundwater system through which it is passing.This paper will convey the findings of case studies in which the efficacy of thismethod has been tested in pre-mining surveys.

9:45 AM

Wireless Monitoring of Microseismic Events

J. Whitney; Mining and Minerals Engineering, Virginia Tech,Blacksburg, VA

As safety requirements increase in the mining environment, predictive equipmentand technology must now be utilized in order to increase the overall safety ofmines throughout the country. Microseismic activity is monitored in order to predict

roof falls, rock bursts, high wall failures, and several other structural hazards in themining environment. The use of wireless technology can improve these monitoringtechniques by reducing the cost of the system as well as reducing the time it takesto receive measurements. This paper is a review of the current wirelesstechnologies and microseismic monitoring systems being used today and needsin this area for the future.

10:05 AM

Embankment Stability Under Cyclic Discharge

G. Inci1, H. Kim1 and T. Alexieva2; 1Geo/Civil-Mining, URSCorporation, Denver, CO and 2Mining, MWH Americas Inc.,Denver, CO

The centerline tailings dams usually utilized in precious metal mining haveunique pore pressure and stability conditions. The tailings are typically separatedby cyclones into overflow loose sand on the downstream embankment slope and

underflow slimes in the impoundment. As the dams are raised for storing moretailings, steady-state seepage conditions are achieved by gravity flow betweenthe downstream embankment and impounded tailings. Limit equilibrium slopestability analyses are generally conducted for the steady state seepage condition.However, there are few studies for the effects of this cyclic discharge on thephreatic surface and the stability. In this paper, numerical approaches wereprovided to simulate a realistic cyclic discharge sequence for the centerlineraised tailings dam during operations. Transient stability of the par tially saturateddownstream embankment slope was also analyzed. Results from limitequilibrium analysis show that cyclic discharge can have direct influence on thestability of the slope.

10:25 AM

Excess Pore Pressure Dissipation Measures for Mine Tailings, a

Comparative Evaluation of Stone Columns and Wick Drains

G. Inci; URS Corporation, Denver, CO

Copper and gold mine tailings impoundments are generally composed of uniformcoarse to fine silty sand with some clay. They are loosely deposited and aresusceptible to liquefaction under mid-intensity earthquakes and static loading.Today, some of the copper and gold mines are being reopened because of marketdemands. Moreover, decommissioned tailings impoundments are being utilized asfoundations for storage and road embankments. Although it is not the preferredpractice to place embankments or build structures on liquefiable soils, schedulerequirements and space restrictions are pushing geotechnical engineers to buildover tailing impoundments. Excess pore pressure induced during construction orfrom an earthquake can destabilize the foundation tailings. Stone columns andwick drains are generally used to reduce the excess pore pressure. In this studytransient pore pressure increase in tailings and pore pressure dissipation throughstone columns or wick drains were evaluated with transient seepage analyses.Impacts on stability were quantified with limit equilibrium analyses.

Geology: Rare Earths — Geology, Deposits, and

Economic Assessment


Chair: J. Hedrick, US Geological Survey, Reston, VA

9:05 AM

Geology of the Lemhi Pass Thorium-Rare Earth District, Idaho

and Montana: Evidence for a Buried Paleozoic Alkalic System?

V. Gillerman1, P. Layer2, M. Jercinovic3, M. Gordon4 and M. Schmitz4;1Idaho Geological Survey, Boise, ID; 2Geology & Geophysics, Univ. ofAlaska, Fairbanks, AK; 3Dept. of Geosciences, Univ. of Massachusetts,Amherst, MA and 4Dept. of Geosciences, Boise State Univ., Boise, ID

The Idaho Geological Survey has been studying the Lemhi Pass District, Idahoand Montana. Base metal and iron mineralization predate thorium-REE veins but

are locally coincident. Thorium veins exhibit intense alkali and ferric ironmetasomatism and are enriched in middle REE; identifiable hypogene mineralsinclude monazite, allanite and thorite. Mapping discovered a Cambrian (530 Ma)syenite (cut by hematite veins) and a slightly older suite of altered mafic andlamprophyre dikes in proximity to many of the thorite deposits. Nd-rich monazitefrom the Lucky Horseshoe mine has complex U-Pb zoning, but preliminary resultsshow a younger (recrystallized?) Paleozoic age signature of 300-350 Ma. Leadisotope studies are underway to look at the relationship of the sulfides, thoriumveins and intrusives. Regional associations include Paleozoic igneous rocks (withlocal base metals) intruded along a r ifted continental margin, Th-REE deposits atDiamond Creek, a Th-enriched red syenite, and Cretaceous(?) carbonatitereplacements. Subsequent structural disruption, the Cretaceous thermal overprint,and lack of subsurface data obscure any buried intrusive-hydrothermal system.

9:44 AMGeology and Exploration of the Bear Lodge REE Property,

Wyoming

J. Clark and D. Ranta; Rare Element Resources, Golden, CO

Rare Element Resources has 100% interest in the Bear Lodge property,northeastern Wyoming, which contains extensive gold mineralization (optionedto Newmont Mining) and large disseminated rare-earth-element occurrences.Newmont is earning a majority interest in the property through the Sundance goldexploration joint venture, excluding any rights to the rare-earth elements butincluding rights to gold and other metals. The Bear Lodge property alsoencompasses one of the largest disseminated rare-earth occurrences in NorthAmerica (M.H. Staatz, 1983, USGS Professional Paper 1049-D). The Bear LodgeMountains are composed of the upper levels of a mineralized Tertiary alkaline-igneous complex that has intruded and domed the surrounding Paleozoic andMesozoic sedimentary rocks in the early Tertiary (approximately 38-50 millionyears ago). Rare-earth-element mineralization occurs in carbonatite dikes and

stockworks, and their oxidized equivalents, in the north-central core of the BearLodge dome, which consists of multiple intrusions of phonolite, trachyte, and otheralkaline igneous rocks, and a variety of associated breccias and diatremes.

10:04 AM

The Rare Earths Market: Can Supply Meet Demand in 2013?

D. Kingsnorth; Industrial Minerals Company of Australia, MtClaremont, WA, Australia

The global demand for rare earths has risen from 80,000t in 2000 to an estimated135,000t in 2008. This year China will supply over 90% of the global supply ofrare earths and will consume over 60% of total demand. In the past 12 monthsChina has increased export taxes and reduced export quotas; a trend that is likelyto continue. These recent imposts have had a significant impact on prices andsupply. During the 4th Quarter of 2008 many of the potential new rare earthproducers are scheduled to announce progress on their feasibility studies. Demnd

is forecast to exceed 200,000t in 2013 for the first time. The paper will trace theimpact of recent rare earth industry developments with a forecast of how thepotential supply deficit may be met.

10:23 AM

Rare Earth and Magnetite Enriched Mineral Sands in the Snake

Valley – Deep Creek Range Region, Utah

J. Pearson1, G. Schlenker2, D. Armstrong2, C. Maguffin2, R. McDonald1

and C. Smith3; 1Great Western Minerals Group Ltd., Saskatoon, SK,Canada; 2Kleinfelder, Taylorsville, UT and 3Titan Mining Group LLC,Heflin, AL

The Snake Valley and adjacent Deep Creek Mountains of west central Utah arehost to rare earth and iron enriched mineral sands which have their source in the18.7 Ma Ibapah Stock, a multi-phase, peraluminous granodiorite to quartzmonzonite body intruded into the upper Proterozoic and lower Paleozoic meta-sedimentary rocks of the Deep Creek Mountains. Erosion of the Ibapah Stockcreated alluvial fans which coalesced into an extensive, flat to gently east dippingalluvial pediment of Pleistocene age. Narrow E-W trending channels of alluvialstream deposits erode the alluvial pediment and are flanked by alluvial flood plaindeposits. Overlying and altering the alluvial stratigraphy are paleo-beaches andlacustrine sediments of the Bonneville, Little Valley,and Provo levels of late-Pleistocene Lake Bonneville. Magnetite and monazite are ubiquitous in thesediments eroded from the Ibapah stock with concentrations of 1.6 to 2.8% and0.02 to 0.04% respectively in the alluvial pediment. They are further concentratedin areas of increasing energy giving concentrations of up to 11% magnetite and0.2% monazite and locally massive magnetite beds over widths of 10’s of cm.

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10:43 AM

Geology of the Nolans Bore REE-P-U-Th Deposit, Northern

Territory, Australia

K. Hussey1 and R. Brescianini2; 1Arafura Resources Limited, Darwin,NT, Australia and 2Arafura Resources Limited, Perth, WA, Australia

The Nolans Bore REE-P-U-Th deposit occurs in the central Arunta Region ofAustralia’s Northern Territory. Country rocks include Palaeoproterozoic felsicgneisses and subordinate metasedimentary rocks that have undergone 1600-1570 Ma granulite facies metamorphism. Primary mineralisation cuts laterlocalised pegmatites and is subsequently locally deformed by 330-300 Ma shearzones. Mineralisation occurs mainly as swarms of massive fluorapatite-rich veinsover a 6 km2 area. Individual veins are up to tens of metres wide and hundredsof metres in length. The extent of the mineral system has yet to be fully defined.Currently, resources are estimated at 18.6 Mt @ 3.1% REO, 14% P2O5, 0.018%U and 0.29% Th. Mineralisation is LREE-enriched and has a distinct Ca-Sr-P-REE-Y-U-Th-F geochemical association. The REE are hosted in fluorapatite,cheralite, monazite, allanite and minute inclusions within apatite. Widespread butvariable calc-silicate alteration hosts fluorapatite+allanite mineralisation. Itappears that the primary REE-P-U-Th mineralising event is related to deep seatedfluids with REE derived from an evolved source.

11:02 AM

Supergene REE Deposits in Carbonatites

A. Mariano1, J. Hedrick2 and C. Cox3; 1Consultant, Carlisle, MA; 2U.S.Geological Survey, Reston, VA and 3The Anchor House, Inc.,Evanston, IL

The development of REE minerals from the weathering of carbonatites can, under

specific conditions of climate, geomorphology, tectonics, and other factors,produce vast accumulations of supergene mineralization with respect to gradeand tonnage. Deposits of this type include Mt. Weld, Australia; Araxá, Brazil;Mabounié, Gabon; Tomtor, Russia; and Cerro Impacto, Venezuela. The majorsource of supergene REE mineralization is substitutional impurities in the primarycarbonate minerals calcite and dolomite, and apatite. Supergene REE mineralsinclude monazite, cerianite, crandallite-type minerals, and less frequentlychurchite. The individual crystals are sub-micron in size and are inextricablyassociated with deleterious minerals which thus far have inhibited production ofa marketable concentrate. REE mineralization at Mt. Weld was first reported in1980 in drill core. Subsequent exploration of the laterite by several miningcompanies established impressive grade, tonnage, and REE distribution.Research to produce a viable REE concentrate is under development; this maybe applied to other supergene REE mineralization from various carbonatites.

11:22 AM

An Assessment Of The Reliability Of The Present Determination

Of The Rare Earth Resources and Reserves Of The People’sRepublic of China

J. Lifton; Jack Lifton LLC, Farmington Hills, MI

The “giant’ polymetallic ore deposits in the Bayan Obo region of Inner Mongolia,China are consistently cited today as the largest rare earth element, REE, oredeposit grouping ‘known’ in the world. It was in fact so referred to in a JointU.S.G.S./Academy of Geological Sciences Of the Ministry of Geology and MineralResources of China study of the deposits as a paradigm example of a giantpolymetallic ore deposit of hydrothermal origin published in 1997 (U.S. GeologicalSurvey Bulletin 2143). Yet the estimates of the total reserves of REEs at BayanObo are not confirmed by official Chinese studies based on detailed and openlyreported drilling data, and seem to be based on unofficial estimates and oralcommunications in the first place. I will discuss the influence of Chinese cultureon the estimates of REE reserves in the Bayan Obo region and the influence ofthat culture on the expansion of reserves of REEs. This may be a factor toilluminate an unspoken reason for the recent volatility of REE production in the

Bayan Obo region.

11:41 AM

The Lake Zone Heavy Rare Earth Deposit, Northwest Territories,

Canada

W. Mercer1, J. Pedersen1, D. Trueman1, M. Heiligmann2 andE. Sheard2; 1Avalon Ventures, Toronto, ON, Canada and 2Departmentof Earth and Planetary Sciences, McGill University, Montreal, QC,Canada

The Lake Zone Heavy Rare Earth Element (“HREE”) deposit, on Avalon Ventures’Thor Lake property, is situated 100 km E of Yellowknife, NWT. It is hosted by theAphebian Blachford Lake peralkaline layered intrusive complex within Archeansupracrustal rocks of the Slave Structural Province. It is an unusual rare earthelement (REE) deposit for its exceptionally high HREE (Eu through Lu + Y)content. The REE mineralization, is hosted in a tabular hydrothermal alterationzone, over an area in excess of one km2, and averaging 100-150m thick in

thickness. It is characterized by nearly complete replacement of the primarymineral assemblage by magnetite, biotite, albite, zircon, allanite, bastnaesite,monazite and fergusonite. The deposit exhibits distinct horizontal layering withHREE content generally increasing towards the base. The lowermost layer, calledthe “Basal Zone” contains between 1.5 and 2.5% TREO over about 20m, withHREE ranging between 15% and 30% of the total REE present. Current work isfocused on resource definition and metallurgical testwork for a pre-feasibilityeconomic study due in early 2009.

Industrial Minerals: New Technologies


Chair: S. Ravishankar, Cytec Industries Inc, Stamford, CT

K. Conner, Freeport-McMoRan, Safford, AZ

9:05 AM

Vibrating Equipment Monitoring Technology

M. Garrison1, R. Kuehl II1 and C. Mapes2; 1Vibrating Equipment,Metso Minerals Industries, Inc., Columbia, SC and 2Mining, GlobalLarge Crushers, Metso Minerals Industries, Inc., Waukesha, WI

Electronic advances now quantify multiple mining processes previously monitoredonly qualitatively, such as vibrating screen performance. Mechanical performancehas been discerned via throw cards - a subjective “art” fraught with non-repeatableimprecision. Metso Minerals has developed two new technologies, both patentspending, that precisely quantify screen mechanical performance. The LSB is a

hand-held technology that quantifies orbits, structural integrity, and bearingconditions. The technology ensures correct installation and suppor ts long screenlife, reduced operating cost, and maximum process efficiency. Often used as anauditing tool, significant use of the LSB has clarified the relationship betweencustomer structure and moving machines, prompting improved design. A SSP(Screen Security Package) advances this technology to full condition monitoring,online or intermittent, local or remote. Since new machines have performancesignatures developed on a Pilot Stand upon assembly, these signatures arereferenced upon startup to ensure correct installation. With the digital record,ongoing monitoring serves to allow conversion to full predictive maintenance.

9:25 AM

Significant Developments in Dry Rare-Earth Magnetic

Separation

M. Dobbins and I. Sherrell; Minerals Processing, Physical Separation,Outotec (USA) Inc., Jacksonville, FL

The advent of the more efficient and effective rare-earth roll (RER) separator inthe early 1980’s began a new era of dry magnetic separation. The RER unitsquickly became the separator of choice within the materials processing industry.Though RER’s are now commonplace throughout the world, only modestadvancements have been made to the original design. This paper details recent,more significant, rare-earth magnetic separation developments. Thesedevelopments maintain the best features of existing technology while minimizingshortcomings. The discussion includes discerning features that aid in bettermetallurgical performance over a broad size range of materials. Also discussedare improved mechanical aspects that allow for both easier operation andmaintenance. Performance details from various test programs are included.

9:45 AM

Maximizing Air Quality Inside Enclosed Cabs with Uni-

Directional Filtration and Pressurization System

A. Cecala1, J. Organiscak1, J. Zimmer1, M. Hillis2 and D. Moredock3;1NIOSH, Pittsburgh, PA; 2Vulcan Materials Company, Birmingham, ALand 3Sy-Klone International, Jacksonville, FL

Enclosed cabs have been used on surface mining equipment for many years toprotect equipment operators from health and safety hazards. The surface miningand quarrying process is a highly mechanized process that generates largequantities of respirable dust. Due to economical factors, more older miningequipment is being used today than in years past. With this older equipment, it iscommon to observe deterioration of many components on the enclosed cabswhich greatly reduces its effectiveness. NIOSH has recently completed acooperative research effort with Sy-Klone International and Vulcan MaterialsCompany to evaluate the effectiveness of a newly designed un-directional filtrationand pressurization system that brings all the clean filtered air in at the roof of thecab and extracts all recirculated air near the floor. This design provides the highestair quality to the equipment operator. Testing on this new system showed a 10-foldreduction in respirable dust inside the enclosed cab. The uni-directional design isvery easy to incorporate and should be considered for all new and retrofit systemsin surface mining equipment.

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9:45 AM

Barrick Operations in Tanzania

J. Shuttleworth; Barrick Gold Corporation, Dar es Salaam, Tanzania

Barrick Gold Corporation is well established in Tanzania East Africa with threeoperating mines; Bulyanhulu, North Mara and Tulawaka. Buzwagi Project is inconstruction and due for start-up in 2009. Kabanga Nickel Project is a joint venturepartnership with Xstrata. The region hosts 19.5 million ounces of proven andprobable gold reserves and produces in excess of 600,000 ounces per year. Theclose proximity of Barrick mines in north-west Tanzania presents significantsynergy opportunities, including shared infrastructure, equipment, personnel andtraining initiatives. This presentation will highlight sustainable developmentprogrammes that Barrick has successfully integrated at its operations in Tanzania.

Water management practices include construction of a 75ha lined water harvestarea at Buzwagi Project; and surface paste tailings disposal at Bulyanhulu. AtBuzwagi over 200 households were relocated in twelve months with positivecommunity engagement, resulting in a world-class achievement. Water andelectricity supply, health care, schools and education initiatives have also beensuccessfully implemented into communities surrounding Barrick’s operations.

10:05 AM

Mining and Exploration in Mexico Today

J. Lee; Exploration, Gammon Gold Inc, Naucalpan, Mexico

In spite of the enormous mineral potential of Mexico, the Country has a greatindex of subexploration, which has kept the minerals production practically staticfor decades.The Secretaria de Economía (*) reports 209 foreign companiesoperating in Mexico in 468 projects. 402 in exploration, 43 in production and 23under development. 160 Canadian, 30 from the USA, 4 Australian, 4 fromEngland, 3 from Japan, 3 from Switzerland, 2 from Luxemburg, and 1 each fromChile, India and Peru.There is activity in 26 States. 335 projects are associatedwith precious metals, 63 copper, 61 polymetallic, 6 iron and the rest otherbyproducts.Nonferrous metals increased their value by 62% from 2005 to 2006,the value of precious metal production increased by 61%. Ferrous group ofminerals (coal, coke, iron, and manganese) increased by 16%. On the other hand,industrial minerals increased their value by only 12.6%.Copper had the highestvalue, representing 37% of the total. Silver had the second highest value with24% of the total mining production value. Zinc, gold, and molybdenum followedwith 15%, 12%, and 5.6% of the total, respectively. (*) Secretaria de Economia.DGM. Annual report 2007.

10:25 AM

Traveling in Brazil

F. Habashi; Mining, Metallurgical and Mat Eng, Laval University,Quebec City, QC, Canada

Brazil is a major mineral and metal producer, has magnificent fauna and flora andsuperb architecture. In 1693 gold was discovered in Ouro Preto and Brazilproduced about half of the world’s gold. In 1726 diamond was discovered in theregion of Tijuco in the Province of Minas Gerais, 150 km east of Bello Hor izonte.The country became independence from Portugal in 1822 as the Brazilian Empire.In 1876, an Englishman succeeded in obtaining from the Amazon region seedsof rubber trees and secretly transferred them to England, where they were plantedin the royal gardens at Kew. Some of the seedlings which spouted were sent toCeylon and Singapore. Thus, began the rubber industry in the East. Today, Brazilis the largest producer of niobium. The Mineral Research Center in Rio de Janeirois the country’s main establishment for mineral research. Brazil has been arepublic since 1889 with its capital in Brazilia.

10:45 AM

Social Responsibility: A Core Business Value of Apex

Silver Mines

P. Castanos; Apex, Apex, Denver, COApex Silver Mines is committed to its role as a leader in corporate socialresponsibility and sustainable development. We believe that this is not only theright thing to do, it is part and parcel of the way we must run our business in orderto ultimately succeed. We are closely linked with the local communitieswhere weoperate. The community members are our labor force and we provide theopportunity for sustainable socio-economic growth. Our commitment toresponsible development has proven to be a strong competitive advantage. Wecan enter diverse countries such as Argentina, Mexico, Peru and Bolivia, andestablish credibility from day one because of our reputation for implementingthese programs. We consider social responsibility to be a core business value ofApex Silver Mines.

11:05 AM

Mining’s Positive Outreach to Feed the Poor- The Clinton Giustra

Sustainable Growth Initiative

P. Dolph; Business Administration, Regis University, Pine, CO

As the mining industry continues to support and improve the living, health, andinfrastructure needs in developing countries, it seldom is given the credit it is due.Recently, President Bill Clinton and Frank Giustra have teamed up to create theClinton Giustra Sustainable Growth Initiative (CGSGI) to advance philanthropiccontributions from the mining and natural resource sectors. CGSGI is focusingon alleviating poverty in the developing world by building on the ClintonFoundation’s successful record of implementing and scaling up developmentinitiatives in other countries. The Clinton Foundation is acting as the implementing

partner, bringing together key stakeholders from the natural resources sector aswell as the business community in the developing world. Already the CGSGI hasreceived funding from Carlos Slim Helú, the Chairman of Grupo Carso who hascommitted over $100 million. Participating companies from the mining industryare also playing a key role in CGSGI. To date, over 20 natural resource, resourcefinance and supporting companies have endorsed or signed on as partners tothe initiative.

Mine Safety & Occupational Health Symposium: II


Chair: J. Brune, NIOSH, Spokane, WA

9:05 AM

Enhanced Fire Escape Training for Mine Workers Using Virtual

Realtiy Simulation

T. Orr1, L. Matthews1, L. Mallett2 and I. May1; 1NIOSH, Spokane, WAand 2NIOSH, Pittsburgh, PA

Recent US mine disasters identified a need for improved training of miners inescape from mine fires and explosions. Researchers at the National Institue forOccupational Safety and Health, Spokane Research Laboratory (SRL), designedand tested fire-escape training software for use in a mine-safety training course.The software allows up to four trainees to work together in a virtual world via acomputer network. Trainees responded favorably and showed a markedimprovement in locating the proper evacuation routes on subsequent trials. Incollaboration with the Pittsburgh Research Laboratory, a more elaborate fireevacuation scenario is being developed and tested. Further research is neededto confirm that virtual training will translate to improved safety outcomes in thereal world.

9:25 AM

Do Light Emitting Diode Cap Lamps Enable Improvements in

Miner Safety?

J. Sammarco and M. Reyes; Department of Health and HumanServices, National Institute for Occupational Safety and Health -Pittsburgh Research Laboratory, Pittsburgh, PA

A miner’s visual performance is critical for detecting mine hazards. Movinghazards are often located in the miner’s peripheral field-of-view, while slip/trip/fallhazards are often located in the forward field-of-view. The research objective is todetermine if light emitting diodes (LEDs) can enable visual performanceimprovements as compared to incandescent cap lamps (INC). The researchpresented focuses on a comparative study of a NIOSH LED prototype, acommercial LED, and an INC camp lamp. Thirty subjects participated in the study;ten subjects in each of the age groups: 18 to 25 years, 40 to 50 years, and 50+

years. Visual performance was quantified by the subjects’ speed and accuracy indetecting hazards; visual performance for disability glare was quantified by theuse of contrast sensitivity tests. The results suggest that LEDs with a visiblespectrum containing more of the short wavelengths could enable visualperformance improvements with respect to disability glare, the detection ofmoving hazards in the peripheral field-of-view, and floor hazards. The NIOSHprototype LED cap lamp provided the best visual performance improvements forthe older age groups in every test.

9:45 AM

Using Mining Injuries in Research Planning

P. Coleman, L. Martini and J. Brune; Spokane Research Laboratory,National Institute for Occupational Safety and Health, Spokane, WA

NIOSH’s Mining Program uses surveillance data to help ensure that researchtargets significant safety & health problems. The purpose of this analysis was toexplore the Mine Safety and Health Administration’s (MSHA) database to find

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areas that might benefit from research and identify the most frequent and/orsevere injuries for prioritizing preventive efforts. Nonfatal days-lost injuries from2002-2007 were studied. Using MSHA’s Accident/Injury/Illness Classification asthe main groups, the five most frequent levels of selected variables werecompared across classes. Handling Material was the most frequent class ofinjury across almost every commodity. Slips or Falls of Person ranked second,followed by Hand Tool, Machinery, and Powered Haulage injuries. Notableclusters included Moving Power Cable (in UG coal for both Handling Materialsand Slips/Falls), and Machine Maintenance & Repair. The potential outcomeshould be to ensure that 1) research projects lead to more effective engineeringcontrols, training, and other preventive measures; and 2) more useful baselineshelp in evaluating the effectiveness of interventions to improve the safety andhealth of miners.

10:05 AMUpdate on Refuge Alternatives: Research, Recommendations,

and Underground Deployment

E. Bauer1 and J. Kohler2; 1Disaster Prevention and Response Branch,NIOSH, Pittsburgh, PA and 2Office of Mine Safety and Health,NIOSH, Pittsburgh, PA

In response to the mandates in the MINER Act of 2006, NIOSH conductednumerous refuge alternatives research efforts that included characterizing theutility, practicality and survivability of refuge chambers and outby safe havens.NIOSH also prepared and delivered a report to Congress in late December 2007that summarized the findings of the research, focusing on specific informationthat could inform the regulatory process on refuge alternatives. The report alsoincluded recommendations concerning the design and performance specificationsfor refuge alternatives. This presentation highlights NIOSH’s research andrecommendations concerning refuge alternatives, survivability evaluations ofrefuge chambers, and a review of the current deployment of refuge chambers inunderground coal mines in the U.S.

Minerals Resource Management: Mining and EconomicDevelopment: Making the Link to Sustainability


Chair: S. Knoerzer, Freeport McMoRan Copper and Gold, Phoenix, AZ

T. Bame, Freeport McMoRan

9:05 AM

Resource Booms and the Poor

G. Davis and A. Vasquez; Division of Economics and Business,Colorado School of Mines, Golden, CO

There are frequent suggestions that domestic extractive activity increases anation’s poverty rate. Those who suggest this negative relationship often infer thatthere are dynamic effects at work, such as increasing income inequalityassociated with extraction-led growth or Dutch Disease effects that reducemanufacturing employment. None of these studies, however, directly examine thedynamics of mineral extraction and poverty. This paper uses a unique World Bankdata set on income growth by quintile across 88 countries to statistically assesshow changes in extractive activity affect the poor. We firmly reject that increasesin extractive activity are bad for the poor. In some of our test specifications we infact find that increasing extractive activity is decidedly good for the poor. Thisimpact appears to come from direct income growth in the lowest quintile of theincome distribution, contradicting the many studies that assert that mineralextraction benefits only a wealthy elite.

9:25 AM

Partnerships for Sustainable Development in Ghana: Integration

of Leading Practice in the Design and Implementation of

Sustainable Development Programs at the Tarkwa and Damang

Gold Mines in Ghana

T. Aubynn; Corporate Affairs and Social Development, Gold FieldsGhana, Airport, Accra, Ghana

A key challenge that confronts many mining companies operating in developingcountries is how to maximize the effectiveness of, and return on investment fromtheir sustainable development programs. In the past many mining companies’social responsibility efforts have been primarily aimed at enhancing publicinfrastructure in communities where they are located, with a focus on education,water and sanitation, and health. The sustainability of the infrastructure and/or itsfunction has been at risk due to insufficient capacity in beneficiary communitiesand local government to manage and maintain them. This situation has oftencreated the risk of permanent and un-sustainable dependence upon company

resources. This paper utilizes a case study of Gold Fields Ghana (GFG) todescribe the various components of a successful strategy designed to maximizethe effectiveness of corporate sustainable development programs. The GFGmodel represents a leading example of best practice in the international miningindustry for community engagement and sustainable development.

9:45 AM

The Role of the Extractive Sector in Expanding Economic

Opportunity

H. Wise; Wise Solutions LLC, Arlington, VA

In 2007, energy and mining companies were among the largest and mostprofitable companies in the world, yet the communities from which thesecompanies extract commodities are among some of the poorest. Expandingeconomic opportunity in the communities and countries where they operate is inextractive companies’ best interest, since the industry is by nature sensitive tolonger time horizons as well as economic and political stability. Companies cansimultaneously improve their surrounding communities and serve their owninterests by nesting an economic opportunity expansion approach into the corebusiness operations of procurement and sales. Companies maximize businessand social potential by creating business models that include the poor, developinghuman capital, building institutional capacity, and optimizing the “rules of thegame” to improve access to business opportunities.

10:05 AM

Non-Profit Partnerships for a Sustainable Solution to

Global Poverty

C. Crane, President and CEO, Opportunity International

Committed to solving global poverty since 1971, Opportunity International hashelped poor communities around the world develop prosperous economies.Currently providing microfinance services in 28 developing countries, Opportunitysupplies the poor with the financial tools necessary to work their way out ofpoverty. By partnering with corporations and other organizations, Opportunityhelps equip poor entrepreneurs with loans, savings accounts, insurance andtraining. A successful partnership with the Caterpillar Foundation has allowedOpportunity to provide loans as well as safety training to workers in China.Opportunity works to help the poor build stable and productive communities andcreate reliable employment opportunities.

Mining & Exploration: Mine Automation


Chair: M. Bartlett, Freeport McMoRan Mining Company, Safford, AZ

9:05 AM

Review of Wireless Tracking and Proximity Warning Systems for

Surface Mining

M. Furniss; Mining and Minerals Engineering, Virginia Tech,Bechtelsville, PA

In the pursuit of safety and higher production, the mining industry has developedseveral systems that could be used as stepping stones towards full mineautomation. Full mine automation is an ultimate goal that is far from beingachieved in today’s industry. The next necessary step is to merge a wirelesstracking system with a proximity warning system. This paper will review some ofthe available proximity warning systems on today’s market as well as the latestavailable tracking systems for surface mining.

9:25 AM

How to Reduce Collisions and Increase Automation with

Radar Systems?

R. Winkel2 and K. Nienhaus1; 1BGMR Excavation and MiningEquipment Group, RWTH Aachen University, Aachen, Germany and2indurad - The Industrial Radar Company, Aachen, Germany

Radar Technologies are successful implemented in the military industry sincedecades and found recently their way in the mining industry as level gauge radarsfor bins. The latest generation of microwave radar sensors are capable to providegeometrical data of the surrounding area of mining machines. Radar sensors arean improvement to laser scanners as they are more robust and able to penetratedust and mist. Radar sensors will be the key source for operator assistancesystems. The key objectives for these applications are: - Performance, productivityand profitability - Condensing Information for smaller crews - Prevention of truckand excavator damages - Improvement of safety and ergonomics. The authorsconducted a large series of tests within open pit mines and underground coal

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on the machine by operating within OEM specifications. The unmanned dozercan follow the planned path ensuring optimal ripping by maintaining a consistentrow width and ripper penetration. Optimal ripper penetration can be commandedbased on rock type. Automatic depth adjustments are made based on sensorfeedback to ensure forward progress without undue strain on the machine.Automation of the dozer also makes it possible to capture performance statisticsduring ripping operations. The production rate in a single ripping operation iscalculated based on automatic computation of the volume ripped per cycle time.Productivity statistics can be obtained from actual performance measurements bycomparing them with the geometry and estimated timing of planned assignments.

Mineral & Metallurgical Processing: Collaborative

Research: AMIRA International9:30 AM • Tuesday, February 24

Chair: T. Braden, AMIRA International, Aurora, CO

9:35 AM

“What is P9”

E. Manlapig; JKMRC, Indooroopilly, QLD, Australia

The Julius Kruttschnitt Mineral Research Centre has focussed research on thedevelopment of equipment, tools and methods that will reduce the energyrequirement in mineral processing plants. This research is being done inconjunction with the mineral processing industry as well as part of major researchprojects with other research institutes. This paper will introduce the overall strategyand outline the priorities that have been established to achieve this objective.

Energy in comminution will be addressed but it will also consider how to separateat coarse sizes liberated minerals as a part of an overall strategy for energyoptimisation.

9:55 AM

The Hydrometallurgy of Gold Processing in the AMIRA P420C

Project

B. Staunton; Parker CRC for Hydrometallurgy, Murdoch, WA,Australia

This paper will outline the research conducted in the AMIRA P420C Project anddiscuss the benefits received from the research.

10:15 AM

Electrowinning of Copper and Zinc and the Associated Problems

M. Nicol; Parker CRC for Hydrometallurgy, Karawara, WA, Australia

This paper will present findings from the AMIRA P705A Project.

10:35 AM

Flotation Research Continues in AMIRA’s P260D Project

J. Ralston; University of South Australia, Adelaide, SA, Australia

This paper will present the findings related to flotation of the AMIRA P260Dproject.

10:55 AM

Solids Dewatering in the Minerals Industry

J. Farrow; CSIRO Minerals, Karawara, WA, Australia

This paper will present the findings from the AMIRA P266F project.

mines to determine the potential of different electronically scanning radar sensors.Several applications were determined as highly feasible and are now in theimplementation stage. The authors are giving an insight in the experimentalresults, the implementation and an outlook for the range of applications wherethis technology could be valuable in the US mining industry.

9:45 AM

Control Room Design Techniques for the Automated

Surface Mine

S. Dessureault and V. Tenorio; Mining and Geological Engineering,University of Arizona, Tucson, AZ

The introduction of autonomous technologies in Open Pit Mining demands themodification of traditional operations management. A fundamental change in pitaccess and process control will necessitate the redesign of frontline managementfrom the traditional largely visual-oral interactions between foremen andoperators, to a “coordinate and control” system. A fully integrated mine-widefrontline management control room is assumed to represent the most efficientmeans of ensuring the level of control necessary for maintaining safety andproductivity. This presentation will review existing control room design approachesranging from military to computer-integrated manufacturing. The adaptations ofsuch approaches for a mine environment through reasoning and the results ofexperimentation at a semi-autonomous surface mine will be reviewed.

10:05 AM

Considering a People Strategy to Enable the Successful

Deployment of Process and Technology

L. Mottola1 and S. Holmes2; 1Mottola Consulting, Montreal, QC,Canada and 2Mine Technology Group, Freeport McMoRan Copper &Gold, Safford, AZ

When planning a large-scale technology development program, it isrecommended to carefully consider the integration of people, process, andtechnology as one overarching strategy. Far too many promising techology roll-outs have failed to deliver on expected results. Addressing process changes aswell as a people strategy to support and enable technology is a difficult task whichmust be embedded in the overall program management at an early stage. Thispaper presents one possible approach currently being used in the developmentof a surface mining automation program in the USA.

10:25 AM

Mine Systems Integration for Successful Mine Automation

T. Skinner; SMART Systems Group, Calgary, AB, Canada

The Mining industry, both mining companies and OEMs, are committing human

and financial resources to rapidly advance machine automation in the miningindustry. Automation is seen as a needed strategic thrust to achieve improvementsin mining productivity, safety, and to minimize the current and worsening dearthof human resources for mining. Many companies quote innovation and technologyas strategic components of these automation strategies. A critical success factorin mining automation is mine operating integration and a systems approach.Mines and OEMs cannot automate in isolation as this approach will not only failto spur innovation, but will also cause both automation and technology to fail. Thispresentation will address the need for mine systems integration, connectivity, andcommunications, and what is needed to support the success of mine automationand autonomous mining.

10:45 AM

Staged Autonomous Haulage System Development

M. Baker; CheckMark Consulting, Inc., Tucson, AZ

As advances in computer and control technologies continue to evolve, the

question of full or partial autonomous equipment development continues to floatin the industry. Some key players in the industry have considered that it might bebetter to first introduce the required component technologies to manned vehiclesbefore combining them into a total autonomous system. Many believe the miningprocess is too difficult to introduce such complex component technologies as acomplete packaged system at this time. This presentation will address some of thepros and cons related to the staged development and introduction of componentautonomous technologies in the mine haulage process.

11:05 AM

Autonomous Dozer for Leach Pad Ripping Operations

S. Gray; Autonomous Solutions, Inc., Petersboro, UT

An autonomous dozer has been developed for unmanned leach pad rippingoperations to study the benefits of automating the ripping process. By substitutingthe operator with autonomous technology, operations become more consistentand predictable thereby increasing productivity as well as reducing wear and tear

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Mineral & Metallurgical Processing: Crushing & Grinding:The Next Generation


Chair: H.Walqui, Cleveland Cliffs Michigan Operationd, Ishpeming, MI

9:35 AM

Mill Head Castings - Educating Opinions

V. Svalbonas1, J. Prunier2, J. McGoldrick3 and J. Sun1; 1MetsoMinerals, York, PA; 2Ferry Capitain, Joinville, France and 3Hodge

Foundry, Greenville, PA

Everybody has an opinion what the quality of a grinding mill head casting shouldbe, yet extremely few take the time, or get the opportunity, to compare theiropinions against fitness-for-purpose data. The real question is not how flawlessthe casting should/could be, but rather how long will “this” casting survive inoperation. To validate an opinion on this topic one needs either extensive historicaldata, or comprehensive experimental data, or preferably, a combination of both.The same data can also be used to establish the conservativeness, or lackthereof, of analytical prediction methods.

9:55 AM

Revalations from Functional Performance, Part 1: Water Usage

and Classification System Performance

R. McIvor; Metcom Technologies, Inc., Ishpeming, MI

Functional Performance Analysis of ball (or pebble) milling circuits allows us toisolate the Classification System Efficiency from the Mill Grinding Efficiency. Thefactors which influnence Classification System Efficiency (the percentage of themill solids content which are the targeted “coarse” size of the material beingground) are described. Water usage at the classifiers is of particular importance.Analyses showing that classifier water usage has an enormous effect (up to 30%)on grinding circuit efficiency are presented.

10:15 AM

The Use of Positron Emission Particle Tracking for Investigation

of the Media Flow Patterns in Vertical Stirred Media Mills

N. Rowson2, R. Greenwood2, J. Hart1, D. Skuse1, D. Gittins1, X. Fan3,K. Waters4 and R. Tamblyn1; 1New Technology Group, PerformanceMinerals, Imerys, Par, United Kingdom; 2Dept of ChemicalEngineering, University of Birmingham, Birmingham, UnitedKingdom; 3School of Physics, University of Birmingham, Birmingham,

United Kingdom and 4Dept of Engineering and Earth Science,Imperial College, London, United Kingdom

Vertically stirred media mills are a highly effective low-footprint solution for theultrafine grinding of industrial minerals. This work investigates the of media densityon flow patterns within the mill. Direct irradiation of a media particle leads to decaythrough positron emission, consequently forming two anti-parallel gamma rays,which allow for the real time tracking of particle position. Grinding media of thesame size, but with a range of specific gravities are followed using this method,and the effect on the flow within the mill is revealed. The technique is seen to bean effective method to highlight the velocity profiles within the mill, as well as thezones where grinding is less efficient – areas of relatively low velocity and highresidence time. The changing media is seen to effect the overall flow patternswithin the mill, having consequential effects on the efficiency of the grind.

10:35 AM

Modelling of Ore Textures

C. Bazin; Mining and Metallurgical Engineering, Laval University,Quebec, QC, Canada

A computer program was developed to generate ore textures with various mineralcompositions, grain sizes and preferential associations between minerals. Theore texture is generated using a 3-D seed implementation and crystal growth inrandom and/or preferential orientations. The generated 3-D texture can besampled as sections in various directions and analyzed using stereological tools.The usefulness of the autocorrelation and cross correlation functions is illustratedwith applications for characterizing the size of the mineral grains and thepreferential associations between minerals. The generated 3-D ore texture can bebroken into smaller fragments to simulate comminution. The actual 3-D fragmentsvolume and surface compositions can be calculated and compared to resultsobtained from the analysis of polished sections of these fragments. The deviationbetween the actual fragment composition and the 2-D results provides clues tothe corrections required to obtain unbiased estimated of mineral liberation frompolished sections.

10:55 AM

Pebbles and Slurry Flow in the Pulp Lifters of SAG Mills

R. Rajamani; Metallurgical Engineering, University of Utah, Salt LakeCity, UT

Many advances have been made in improving the breakage rate of large oreparticles in SAG mills. A significant advance is the design of shell lifters via thediscrete element method. Here, a simulation of the charge motion in the mill iscarried out. However, there is another issue that can reduce the capacity of SAGmill. It is well known that slurry pooling is a significant factor in determining thecapacity of the mill. In large mills, crash-stop studies readily reveal the existenceof slurry pooling. Such pooling is an indication of the lack of flow capacity in thepulp lifters. Furthermore, slurry pooling diminishes the rate of breakage in the mill.

In this study, first a detailed study of grate and pulp lifters done in a pilot scale millis discussed. In particular, the evidence is presented regarding the location ofpulp discharge through the grate slots. Next, crash stop studies and related effectson mill capacity done in a plant scale mill are presented. Finally, a detailed discreteelement simulation study of large scale radial and curved pulp lifters is presented.Important issues concerning the design of pulp lifters are discussed.

11:15 AM

Effect of Grinding Media Shapes on Breakage Distribution

Function

H. Ipek; OGU, Eskisehir, Turkey

ABSTRACT In the present study, the effect of grinding media charge on breakagedistribution functions was investigated. Balls and cylpebs were used as grindingcharge for comparison in respect to mass and surface area. It has been observedthat the breakage distribution function is dependent on the feed size but

indepented of the shape of grinding media. The effect of grinding time onbreakage distribution has also been investigated. As a result of a ten minutesgrinding, the balls have produced relatively larger product compared to cylpebs.INTRODUCTION Cylpebs are slightly tapered cylindrical grinding charge withlength equaling diameter, and all the edges being radiused. An importantadvantage of Cylpebs over balls is that Cylpebs produce narrower granulometricdistribution due to their shapes. However, some discrepancies were found in theliterature regarding the milling performance of Cylpebs in comparison with balls(Chi, 2004). The aim of the present paper is to compare the effects of cylpebsand balls on the breakage distribution function of quartz with respect to samemass and same surface area.

Somasundaran Symposium: Education andTechnology Transfer


Chair: B. Parekh, Univ. of Kentucky, Lexington, KY

9:35 AM

Organizational Structure for Sustainable Management of Mineral

Resources

J. Botin; Explotacion de Minas, Universidad Politecnica,Madrid, Spain

Today, most mining companies declare their commitment to the values ofsustainability in their vision declarations and policies, but not many achieve anefficient integration of those values down into the operational levels of theorganization. Corporate commitment is an essential condition for integratingsustainability, but is not sufficient. Another key condition is a business culturewhere sustainability is a high professional and business value and sustainabilityobjectives are implemented through commitment rather than compliance.Furthermore, the integration process requires of an organizational structurespecific roles and integration mechanisms and adequate management systems.In this paper we focus on the integration of sustainability down to the operationallevels of mining companies, the organizational structures and the managementroles and systems required for integration.

9:54 AM

Sustainability in the Gold Mining Industry: Challenges and

Solutions

M. Upton; Resource Initiatives, Denver, CO

Companies engaged in the gold mining industry, from exploration to minedevelopment and operation, are subject to increasing scrutiny and risingexpectations to demonstrate leadership in a broad range of areas falling under therubric of sustainability. Generally, these programs and policies pertain toenvironmental stewardship, community engagement and workplace health &

59



safety, though additional areas can include protection of shareholder value,disclosure/transparency, and continuous improvement mechanisms. In response,large gold producers have implemented a broad range of sustainability programs.These programs will be discussed as well as the proliferation of internationalsustainability protocols (IFC Performance Principles, ICMM SustainableDevelopment Principles, Equator Principles, International Cyanide ManagementCode, et al) and the extent to which they are successfully adopted by gold miningcompanies around the world.

10:13 AM

Sustainable Management of Industrial Minerals from Mine to

Manufacturing

J. Kogel1, N. Trivedi3 and M. Herpfer2; 1Lands and Mines, Imerys,Sandersville, GA; 2Oil Dri, Vernon Hills, IL and 3Idekin International,Easton, PA

Industrial minerals play a central and dual role in the sustainable development ofnatural resources.Over the past decade the mining industry has increasinglyfocused on sustainably extracting and processing industrial minerals. This trendhas been driven by increasing energy costs, diminishing water resources and ageneral sensitivity towards environmental stewardship.Although industrialminerals have been used throughout human history often as low cost, naturallyoccurring, functional materials, today they are critical components of recycledpackaging, energy efficient building materials, light weight paper coatings, andother products critical to the responsible utilization of global resources.Asindustrial minerals become more widespread in “green” manufacturing miningcompanies have established best practices for the sustainable development ofthese mineral resources.Management practices include reducing energyconsumption, minimizing water usage, increased waste recovery throughrecycling and process optimization, and maximizing the amount of ore extractedper acre of disturbed land.Several case studies demonstrating these practiceswill be presented.

10:32 AM

Collaboration Between Mineral Industry Companies and

Universities

J. Herbst and A. Thulin; Metso Minerals, Kailua Kona, HI

Collaboration is not only viable it is critical for future developments in the MineralIndustry to occur. This paper describes a Collaboration Initiative designed toadvance fundamental process understanding through research and to attractbright students into mineral programs in universities and ultimately to producethe needed leaders in academia required to strengthen our industry in the future.Challenges and early successes are described.

10:51 AM

A Vision for Sustainable Resource Development in UniversitiesM. Poulton; Department of Mining and Geological Engineering,University of Arizona, Tucson, AZ

The current economic conditions in our states are once again putting small miningengineering programs under intense scrutiny for their high costs, and relativelylow enrollments and external research support. The difference between thescrutiny now and that in previous economic down turns is the great prosperity ofthe minerals industry and a new emphasis on sustainable resource developmentthat gives mining programs an opportunity for more relevance on campus. Thescientific discoveries and technological breakthroughs necessary to developcritical minerals with the highest level of environmental stewardship require apartnership not just of industry and academia but across many different disciplineswithin academia. We can use the exceptional natural and human competitiveadvantage that exists in some of our universities to build the research capacitythat can lead a step-change in the responsible and sustainable use of earthmaterials that are the basis of nearly every material we use. Stronginterdisciplinary collaboration is fundamental to developing the technologies thatassure sustainable development of critical materials.

11:10 AM

International Education of Mining Engineers – An Update on the

Australian Experience and International Opportunities for

Collaboration

B. Hebblewhite; School of Mining Engineering, University of NSW,Sydney, NSW, Australia

Collaboration between education providers is the key to long-term sustainabilityand improved quality in mining education. Mining staff can find themselvesdeployed anywhere in the world. The mining engineer of tomorrow must be willingto accept this international challenge, and must be educated to a level where heor she has a comprehensive grounding in all aspects of mining engineering, plusa well-founded appreciation of management, social, environmental and culturalissues. To deliver such an education, academic providers must collaborate

nationally, and internationally. This paper provides an overview of progress inAustralia through the national joint venture – Mining Education Australia (MEA).MEA has been operational since 2007 and is developing innovative courses anddelivery methods. MEA has commenced some international initiatives which area catalyst for a far greater degree of international collaboration in the future. Suchactivity benefits the students, but also ensures individual university programsremain viable in terms of staffing numbers and financial performance.

11:29 AM

Sustainability of Namibian Artisanal Mining

B. Ross1 and K. Ross2; 1Resolution Copper Mining Limited,Superior, AZ and 2Mining Engieering and Management, SouthDakota School of Mines, Rapid City, SD

Although much of the mining industry is experiencing unprecedented growth andprosperity, many of the artisanal and small scale miners of developing countriesstruggle to survive. Artisanal miners utilize hand tools to manually produce theminerals they market. The work is hard, dangerous and can be harmful to theminer’s health and the environment. Because the miners receive low prices fortheir minerals they are unable to invest in the tools or training to improve theirproductivity, safety, health or environment impacts. This paper examines thesustainability of the artisanal miners of Namibia who produce mineral specimenfor collectors, gemstones and various ores such as tantalite. Topics in this paperinclude the minerals that are mined, the mining methods utilized and theconditions that the miners live and work. This paper also discusses efforts toimprove the sustainability of the Namibian artisanal miners through efforts toassist the miners market their minerals and help from the Small Scale MinersSupport Forum.

11:48 AM

The Role of Process Mineralogy in Mineral Processing

D. Bradshaw and M. Becker; Chemical Engineering, University ofCape Town, Cape Town, South Africa

One of the demands associated the recent gain of momentum of ProcessMineralogy is that mineral processing practitioners are expected to understand themineralogy of their ores. For many more experienced practitioners, this isexpected as they have an inherent basic understanding of mineralogy since itwas part of their education. Their training acknowledged that mineral processingwas the process of exploiting differences in mineral properties. However, as moreand more mineral processors have been educated in other departments e.g.Chemical Engineering they do not always have an adequate working knowledgeof mineralogy. In addition to this, there has been the development of sophisticatedanalytical equipment customized for mineralogical analysis of metallurgicalsamples. This provides the opportunity for more detailed information, particularlyin the processing of problematic or complex ore bodies. The combination of thesecircumstances has created the need and opportunity for bridging courses at

various levels. This presentation discusses a workshop approach adopted at theUniversity of Cape Town to meet this demand for teaching in process mineralogy.

Somasundaran Symposium: Research, Characterizationand Measurement Systems II


Chair: D. Bradshaw, University of Cape Town, Cape Town

9:35 AM

Liberation-Limited Grade/Recovery Curves from X-ray Micro CT

Analysis of Feed Material for the Evaluation of Separation

Efficiency

J. Miller, C. Lin, L. Hupka and M. Al-Wakeel; MetallurgicalEngineering, University of Utah, Salt Lake City, UT

Characterization of feed material with respect to expected concentrate grade andrecovery is fundamental to the design of improved separation efficiencies and toachieve sustainable development in the utilization of our mineral resources. Animportant reference point for this characterization is the liberation-limitedgrade/recovery curve which represents the perfect separation, the best separationwhich can be achieved for a given feed material limited only by the extent ofliberation. Now, liberation-limited grade/recovery curves can be determined basedon 3D mineral liberation analysis and actual separation efficiencies compared towhat might be expected for a perfect separation limited only by the extent ofliberation. It is shown that 3D mineral liberation analysis based on X-ray microCT (XMCT) is preferred to 2D section analysis which overestimates the extent ofliberation. By way of example, procedures and experimental results are presentedand discussed for feed material in the case of phosphate rock flotation.

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9:47 AM

Development of Machine Vision Systems for Sustained

Consistent Flotation Plant Operation

S. Morar, D. Bradshaw and M. Harris; Department of ChemicalEngineering, University of Cape Town, Cape Town, South Africa

In general, machine vision systems that have been developed to for use inflotation have utilised empirical relationships between froth surface descriptorsand performance, which are known to change over time, with variations in feedand operating conditions. Within the literature, the following general empiricaltrends have been demonstrated under certain conditions: Froth velocity isproportional to solids recovery. Froth velocity is inversely proportional toconcentrate grade. Air flow rate, is proportional to froth velocity. Coalescence onthe froth surface is inversely proportional to concentrate grade. Benefit has beenshown in using these relationships, where the operation of flotation circuits haveimproved, however, these empirical relationships limit the ability to which thesestrategies can be used to optimize flotation circuits. This paper presents ananalysis of the value and limitations of using these empirical trends and discussesan approach linking froth surface descriptors to mechanistic phenomenon. Therelationships derived from this approach use mechanistic assumptions which canbetter withstand variation in feed and operating conditions.

9:59 AM

Characteristics and Flotation Behaviour of the PGE Arsenide,

Telluride and Sulphide Minerals

N. Shackleton1, C. O’Connor2 and V. Malysiak1; 1MetallurgicalServices, Anglo Research, Johannesburg, South Africa and2Chemical Engineering, UCT, Cape Town, South Africa

The aim of this study was to investigate whether there was a difference in thefloatability between the PGE sulphide, arsenide and telluride minerals. It had beensuggested, from empirical observations on plants, that sperrylite and moncheiteare poorly floatable minerals compared to the PGE sulphide species and that thisaccounts for a significant loss of PGE in flotation processes. In general, it hasbeen shown that the PGE minerals float readily when treated with SIBX and theXPS and ToF-SIMS results showed clearly that xanthate is adsorbed on themineral surfaces at a higher concentration compared to the copper activatedminerals, except for the sperrylite (NS146) and cooperite (NS144) samples.Oxidation of the PGE telluride minerals was shown to negatively affect theflotation performance of the bismuth-rich samples but not the pure Pt and Pdtelluride samples. Copper sulphate was found to have a negative effect on therecovery of all of the synthetic PGE mineral samples, with the exception ofvysotskite, when compared with the results obtained in the presence of xanthateon its own. Keywords: Microflotation, PGE, surface characterisation, copperactivation and SIBX.

10:11 AM

Nanobubbles, Dissolved Gas, Boundary Layers and Related

Mysterious Effects in Colloid Stability

J. Ralston; Ian Wark Research Institute, University of South Australia,Adelaide, SA, Australia

The role of dissolved gas in enhancing the interaction between suspendedparticles and air bubbles has been known for many years. E.N. Harvey showedhow surface heterogeneities now immortalized as “Harvey Nuclei”, exert a majorinfluence on bubble nucleation. There has been a long and intense debate aboutthe origin and distance dependence of the hydrophobic force, first “detected” insurface force studies. It is now realized that dissolved gas plays a crucial role indetermining the extent of interaction of this hydrophobic force, as does the surfaceheterogeneity of the solid in contact with the aqueous solution. In the absence ofdissolved gas, DLVO theory is entirely adequate in explaining the interactionbetween hydrophobic colloid particles. With dissolved gas, understanding thatheterogeneous surfaces are decorated with nanobubbles and that the surface

nanobubble-nanobubble interaction is dominant, permits the colloid stability to bepredicted by a simple modification of extant DLVO theory. These results are inaccord with theoretical predictions and experimental observations of only veryshort range per turbations of water structure adjacent to smooth hydrophobicsurfaces.

10:23 AM

Nonlinear Population Balance Model (NLPBM) for Non-First

Order Grinding Process: Wet Batch Grinding

R. Rajamani and T. Tuzcu; Metallurgical Engineering, University ofUtah, Salt Lake City, UT

Wet grinding exhibits nonlinear kinetics, therefore the linear model used in mostflow sheet simulation packages can only poorly predict grinding kinetics. Theproposed model here is a Nonlinear Population Balance Model (NLPBM) topredict the breakage rate (selection) functions of the wet grinding process.Traditional Population Balance Model (PBM) sets birth and death terms in linear

or first order manner. In the classical PBM, breakage rate depends on theenvironment or conditions in the ball mill while the breakage distribution functionis assumed to be a material property. The NLPBM introduces time-dependentnon-first order breakage rate function to predict acceleration (speeding-up) ordeceleration (slowing-down) and differential mass disappearance of material ineach size interval. The NLPBM is confirmed with a variety of batch ball millexperimental data. It is shown that as fines accumulate in the mill the breakagerate of coarse fractions accelerates.

10:35 AM

Optimising Collector Performance in the Production of High

Grade PGM Concentrates

J. Wiese, P. Harris and D. Bradshaw; Chemical Engineering,University of Cape Town, Cape Town, South Africa

Recently operating philosophy at concentrators processing platinum bearing oreshas started to move from a recovery dominated system to one in which theproduction of high grade concentrates at the expense of some recovery wouldprovide greater benefits in the further upgrading of the platinum group minerals.The low grades usually obtained are associated with the presence of naturallyfloatable talcaceous gangue minerals in all PGM ores. Polysaccharidedepressants,guar gum and carboxy methyl cellulose, are used to improve thegrades of the concentrates. Recent testwork has shown that the use of highdepressant concentrations can prevent any naturally floatable gangue fromreporting to the concentrate. Gangue present in the concentrates would be dueto its entrainment in the froth. Under these conditions higher grades can beachieved. The sulphide minerals, however, become susceptible to depression atthese concentrations. This work examines how the recovery of sulphide mineralsin Merensky ore was affected by the type and concentration of the collector athigh depressant concentration and that the response of the sulphide mineralswas dependant on the type of depressant used.

10:47 AM

Control of Selectivity in Ion Flotation Using Chelating Agents

F. Doyle1 and Z. Liu2; 1Materials Science and Engineering, Universityof California, Berkeley, CA and 2CMP Division, Rohm & HaasElectronic Materials, Newark, DE

Ion flotation shows great promise for recovering and removing metal ions fromdilute process streams, either for environmental compliance or to recover values.This technique uses an ionic collector to transport non-surface active colligendions of the opposite charge from a bulk solution to the solution–vapor interface.With a sufficiently large solution–vapor interfacial area (provided, for example, bysparging gas through the solution), the colligend can be concentrated andremoved along with the collector in a foam phase. A key limitation on using thetechnique in the minerals industry, where many process streams contain a varietyof ions and have relatively high ionic strengths, is the need to control which ions

are interacting with the collector. Here the effect of three different chelating agents,namely dodecyldiethylenetriamine (Ddien), ethylene diamine tetraacetic acid(EDTA) and tr iethylenetetraamine (Trien), on the selectivity of copper, nickel andcobalt, or copper and alkaline earth metal ions, is reported. The results arediscussed in terms of their implications for adoption in the minerals industry.

Tuesday, February 24 Afternoon

Mining & Exploration: Underground Mining Operations:Controlled Blasting and Rapid Excavation: US

1:30 PM • Tuesday, February 24

Chairs: C. Dreesbach, Montana DEQ, Helena, MT

S. Iverson, NIOSH Spokane Research Lab, Spokane, WA

1:35 PM

An Economic Analysis of Controlled Drilling and Blasting

Techniques in Metal/Nonmetal Drift Development

T. Camm1 and H. Miller2; 1CDC NIOSH Spokane ResearchLaboratory, Spokane, WA and 2Colorado School of Mines,Golden, CO

Substantial empiric evidence suggests that the use of controlled blasting anddrilling methods in drift development reduces collateral damage to the surroundinghost rock and minimizes the fracture envelope induced by commonly employedblasting practices. While the direct cost implications of over-break and peripheralblast damage are often significant, the indirect economic ramifications stemming

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3:05 PM

Methane Explosion Modeling in the Sago Mine

G. McMahon; Spokane Research Lab, NIOSH, Spokane, WA

Following the Sago Mine Accident, the Mine Safety and Health Administrationasked the U.S. Army Engineer Research and Development Center to studyseveral possible methane explosion scenarios in the Sago coal mine. The studyused a 1-ft resolution map of the mine to produce a 3-dimensional model of aportion of the mine, including the sealed area where the explosion occurred. Anadvanced 3-dimensional computational fluid dynamics (CDF) code was used tocalculate the explosion pressures within the sealed area, on the mine seals, andin nearby regions of the mine. Based on the best available information on methaneconcentrations and assumptions on homogeneity, layering and mix composition,

three separate initial conditions of methane-air concentrations and location werestudied. This paper discusses the CDF modeling technique, the results of thecalculations, the challenges of conducting this type of modeling, and theadvantages and limitations of CFD modeling to accident investigations of mineexplosions.

3:25 PM

Progress Toward Improved Engineering of Seals and Sealed

Areas of Coal Mines

R. Zipf, J. Brune and E. Thimons; NIOSH - Pittsburgh ResearchLaboratory, Pittsburgh, PA

The Sago mine disaster caused by an explosion within a recently sealed areaprecipitated many changes to mine seal regulations. The mining community hadrelied upon a “build and test” approach to develop seal designs to meet the old 20psi seal design standard; however, the recent MSHA Final Rule on Sealing of

Abandoned Areas of Coal Mines moved the mining community toward the use ofengineering methods for seal design to meet the new higher design pressures.Well-defined engineering approaches for professional engineers to follow to meetthe new seal design requirements require further development. This paper willsummarize the following: 1) Recent additions to the scientific literature aboutworst-case explosion pressures in sealed areas. 2) Recent changes to miningregulations based on the new scientific information. 3) Progress on new researchaimed at addressing the scientific unknowns about sealed areas such asmonitoring systems, recent explosion pressure calculations from the NavalResearch Laboratory and new engineering design procedures for seals from theU.S. Army Corps of Engineers.

3:45 PM

A Systems Approach to Gob Sealing Using Mine Blast

Attenuators Constructed of Available Mine Rock Rubble

M. Sapko1, M. Hieb3, E. Weiss2, R. Zipf2, S. Harteis2 and B. Britt4;1Sapko Consulting Services, LLC, Finleyville, PA; 2NIOSH, Pittsburgh,PA; 3WVOMHST, Oak Hill, WV and 4Applied Research Associates,Inc, Albuquerque, NM

In the past two years, mine ventilation seals have undergone a radicaltransformation. New federal rules have effectively increased the minimum designpressures from 20 psig to 50 psig or 120 psig depending on the location and sizeof the area to be sealed. The ability of monolithic, stand-alone mine seals topractically and reliably meet the full range of current and future seal designrequirements is becoming increasingly uncertain. To develop possible solutions,the West Virginia Office of Miners’ Health Safety and Training, Sapko ConsultingServices, LLC, and the National Institute for Occupational Safety and Health(NIOSH) are collaborating in a research effort where common mine gob and minerubble may be used to construct barriers for use in conjunction with mine sealsfor the purpose of attenuating high-shock loading pressures from a mineexplosion before impacting the mine seals. This paper discusses somepreliminary concepts and findings of a “Mine Blast Attenuator.” Exploratory full-scale experiments conducted at NIOSH’s Lake Lynn Laboratory are promisingand demonstrate a reduction in blast loading pressures of over 100 to 1.

4:05 PM

Methods to Improve Mine Ventilation System Efficiency

C. Pritchard; NIOSH, Spokane, WA

Mine ventilation air is a precious commodity by the time it reaches the workingface. Options that can increase underground air utilization improves workingconditions through better dilution of contaminants and removal of heat. Someexamples illustrated are options for mine shop air ventilation, compressor andpump stations. Air from these work areas is reused instead of being courseddirectly to mine returns, improving system efficiency. Effects on overall minesystem dynamics are discussed.

Coal & Energy: Preparation & Utilization


Chair: R. Honaker, University of Kentucky, Lexington, KY

2:05 PM

Dry Jigging Coal: Case History Performance

R. Snoby; allmineral LLC, Alpharetta, GA

Since its reintroduction in 2002, the modern air jig has processed a wide array

of coals throughout the wor ld. This paper explores the reasons and justificationsfor the installations and provides case history performance data. Specificallyhighlighted are air jig plants processing metallurgical coal in Colombia;bituminous coal in Ohio, Utah and India; and lignite in North Dakota, Texas andSpain. Each installation had unique reasons to justify an air jig plant. It isimportant to note that not all of the installations produced the most ‘cost effectiveyield,’ normally a mantra for coal preparation plant designers and owners. Dry jigging of coal with the modern air jig is a proven unit operat ion for upgradingcoal. It extends the amount of recoverable coal from a reserve, and does so withminimal environmental impact. In some cases, it allows market quality coal to beproduced when no other option is possible. There are few endeavors as satisfyingas producing a product that allows good people to remain, and even prosper, inthe market.

2:25 PM

KeLa Energy Clean Coal Process

T. Flanery and L. Moot; KeLa Energy, LLC, Orlando, FL

Coal continues to be the dominant fuel for electric production worldwide. Prior tocoal utilization, pre-combustion cleaning is typically performed which results in awet fine coal product. The fine coal is often discarded as waste in impoundmentsdue to moisture content and handling issues. The KeLa process makes anengineered, coal-like product from coal fines, which is up to 35% renewableenergy and 30-40% lower in SOx, NOx, and mercury contents, while improvingthe heating value by 15% and reducing the moisture to 2 absolute percentagepoints. This fuel has already been test burned with documented results. KeLa’sprocess enables coal producers to generate a low moisture, high energy fuel fromcoal fines, which benefits the cleaning performed on the coarser coal fractions. Asa result of the high heating value product from the KeLa process, the separationdensity used in the coarse fractions can be increased, thereby significantlyenhancing plant yield. More clean coal tons in the sales column and less wasterepresent a true global optimization of a mining operation.

2:45 PM

Implications of Constant Incremental Quality on Fine CoalDewatering Circuitry

G. Luttrell1, S. Keles1 and R. Honaker2; 1Mining & MineralsEngineering, Virginia Tech, Blacksburg, VA and 2Mining Engineering,University of Kentucky, Lexington, KY

Coal preparation plants play an important role in modern society by providinghigh quality feeds for coal-fired utilities, industrial boilers and metallurgical cokefacilities. Unfortunately, field data indicate that preparation plants are often notoperated under optimum conditions, resulting in lower productivity and lost profits.In many cases, this shortcoming can be attributed to a failure by plant operators(i) to recognize the importance of correctly adjusting plant operating conditions toaccommodate requirements dictated by coal sales agreements within differentcoal markets and (ii) to properly account for variations in product moisture withparticle size across different plant circuits. This paper discusses the importantinfluence of moisture constraints on preparation plant optimization and providesa case study to illustrate the potential gains that can be realized via proper

understanding of plant moisture control.

3:05 PM

Recovery and Utilization of Bottom Ash Magnetics for Coal

Cleaning Medium

R. Honaker1, Z. Akram1 and J. Groppo2; 1Mining Engineering,University of Kentucky, Lexington, KY and 2Center for Applied EnergyResearch, University of Kentucky, Lexington, KY

Dense medium processes are used to clean over 50% of the coal that is fed intopreparation plant facilities worldwide. The dense medium is formed using ultrafinemagnetite which is recovered after the cleaning step using drain-and-rinsescreens and magnetic separators. Despite the high efficiency of the recoverysystem, magnetite losses of around 0.5 to 1.0 kg/ton are common. Consideringthe recent escalation of magnetite to around $300/ton, an alternative source ofmagnetic material from coal combustion bottom ash has been investigated. Arelatively low cost recovery system has been developed. Dense-medium tests

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2:45 PM

Instrumentation of the Homestake Underground Laboratory for

Drawdown Measurements During Dewatering

A. Davis1, L. Stetler1, W. Roggenthen1, Z. Hladysz2 and R. Salve3;1Geology and Geological Engineering, South Dakota School of Minesand Technology, Rapid City, SD; 2Mining Engineering, South DakotaSchool of Mines and Technology, Rapid City, SD and 3LawrenceBerkeley Laboratory, Berkeley, CA

The former Homestake gold mine at Lead, South Dakota, has been selected bythe National Science Foundation as the proposed host site for the DeepUnderground Science and Engineering Laboratory. The deep laboratory and

associated research campus will be developed at approximately the 7400-ft level.Plans also include the development of the Sanford Underground Science andEngineering Laboratory at the 4850-ft level. After the mine’s pumps were shut offin June, 2003, water levels rose to approximately the 4650-ft level by early 2008.Pumps in the 8150-ft deep mine were turned on again for dewatering in April,2008. Instrumentation is being installed in the mine to measure water-leveldeclines during pumping, for later analysis of permeability and related hydraulicproperties of the formation. Pressure-sensitive transducers and data loggers willprovide real-time information on water levels that will be available to interestedparties. Quality of the water also will be monitored as it is pumped out of the mine.

3:05 PM

Climate Change Risk and Impact Assessment for a Global

Diversified Mining Group

T. Geyer and C. Wasilewski; ERM, London, United Kingdom

INTRODUCTION ERM carried out an assessment of physical risks from climatechange across the international business (for the years 2015, 2025 and 2050).The study addressed 163 components of the business and included operatingsites (mines, smelters, refineries), key transport routes (road & rail) and port links.Threats considered included flooding, water shortage, loss of permafrost, storms,rising sea levels and ecosystem adaptation. OBJECTIVES To assess how thebusiness is impacted in terms of: - The key physical climate change threats - Thelocation of the greatest impacts - The likely magnitude of the impact. RESULTSThe analysis quantified the potential annual impact of the physical risk associatedwith climate change, and highlighted the key threats and locations. Theinformation was disseminated across the company’s business units to enablethem include the physical impacts of climate change in their operational andproject planning.

3:25 PM

Green Technology: Optimizing Your Current Environmental and

Sustainable Business Practices through Technology Solutions

D. Longbrake; ARCHIBUS Solution Center - Environment +Sustainability Services, Columbus, OH

The use of technology solutions is critical to organizational success in today’sglobal business climate. Web-based tools that integrate facility management,environmental management and geographic information systems (GIS) cancreate a solution that create a competitive advantage by providing data andmetrics to track assets and measure and report on the status of your sustainablebusiness practices. By consolidating information there is real-time access tocritical information throughout the organization. Information and metrics related toenergy, greenhouse gas, water, waste, environmental compliance, chemicalinventory and hazardous materials can be integrated with real property assets toquickly and easily provide organizational, divisional and/or property-specificsummaries and evaluations with regard to your business operations, sustainabilityprograms and environmental management systems (EMS).

Environmental: Global Acid Rock Drainage (GARD)


Chair: T. Chatwin, University of Utah, Salt Lake City, UT

2:05 PM

A Comparison of Lime Efficiencies between Conventional Lime

Treatment Systems and the Rotating Cylinder Treatment System

T. Tsukamoto; Technology, Ionic Water Technologies, Inc., Reno, NV

Improving lime precipitation efficiency lowers the cost of treating acid minedrainage. Conventional lime precipitation systems often do not effectively utilizelime while requiring significant resources. This presentation analyzes treatabilitystudies comparing the Rotating Cylinder Treatment SystemTM (RCTSTM) toconventional reactor lime precipitation systems. The study addresses metals

removal effectiveness, energy requirements, labor demands, chemicalconsumption, and sludge production at three significant Western United Statesproject sites. The RCTS replaces the reaction vessels, compressors, diffusersand agitators found in conventional systems. Oxidation and mixing isaccomplished by passing acid mine drainage and lime slurry through acontainment cell. The turbulence that is produced provides efficient lime mixingand dissolution, which results in less lime consumed due to the utilization of theavailable alkalinity, and less sludge produced as a result of less lime usage. Thestudy determined that each treatment system effectively precipitated metals andincreased pH, but the RCTS system required substantially less energy, chemical,labor and residence time.

2:25 PM

Numerical Modeling on Parametric Study of Multi-layer Caps toRestrict Oxygen Transport Over Mine Waste

H. Kim1 and C. Benson2; 1URS Corporation, Denver, CO and2Geological Engineering, University of Wisconsin-Madison,Madison, WI

Uncontrolled piles of mine waste containing sulphidic rock and tailings generateacid rock drainage (ARD) when the rock and tailings oxidize. As a cost-effectivestrategy for ARD control, multi-layer caps consisting of geosynthetic layers andearthen materials for minimizing oxidation of sulphidic mine waste are used. Toassess the performance of multi-layer caps to restrict oxygen transport over minewaste a parametric study was conducted with the finite element model todetermine which variables control oxygen transport, and what types of capdesigns are most effective. Results of the parametric simulations presented inthis paper will be used to develop guidelines for design of multi-layer caps formine waste. The results show that presence of a geomembrane has the greatesteffect on oxygen transport, whereas breathing of the drainage layer has the leasteffect. Installing a geomembrane reduces oxygen transport by 40 times, while theweather condition changes the flux by 24 times.

2:45 PM

The GARD Guide Process

T. Chatwin1 and N. Bezuidenhout2; 1INAP, Salt Lake City, UT and2Golder Associates, Johannesburg, South Africa

Research on acid rock drainage (ARD) formation and methods to prevent it havebeen ongoing for over 50 years. The resulting research and guidance documentsare however in disparate references. They are not easily accessible and tend tobe limited in their focus. In June 2007, the International Network for AcidPrevention (INAP) retained Golder Associates to prepare the Global Acid-RockDrainage Guide (GARD GuideTM) that details current best practices to prevent,mitigate and manage ARD. A beta version of the document has been prepared,and INAP is now engaging all stakeholders to vet the beta version. We arerequesting stakeholders to review it, to apply it and to respond to INAP with

comments and suggestions. In its final version the GARD GuideTM will beavailable on the web and will be updated regularly. We are on track to produce atechnically definitive Guide by June 2009.

3:05 PM

Corporate, Regulatory and Community Framework

K. Ferguson; Sustainability Engineering, Vancouver, BC, Canada

Management of acid rock drainage is done within a corporate, regulatory andcommunity framework. Several companies have developed comprehensive setsof policies, guidelines and protocols. The level of guidance from regulatoryagencies varies substantially with more detailed guidelines available in somestates and provinces in North America, the European Union, South Africa andAustralia. Risk assessment is an important part of the framework and should beapplied at each mining phase in order to: establish transparency with governmentregulatory agencies and the public, inform decision making and provide input forpriority setting. Risk assessment includes the following steps: establish the

context, identify the risk, analyze the risk, assess and prioritize risk, treat the riskand review and monitor. The risk posed by ARD should be considered on a site-specific basis and the level and depth of the risk assessment depend on thehazard associated with ARD and the sensitivity of the water resource.

3:25 PM

ARD Process and Prediction

R. Verburg; Golder Associates, Redmond, WA

Chapters 2 and 5 of the GARD Guide discuss the ARD Process and Prediction,respectively. Chapter 2 defines the types of mine drainage, discusses the historyof ARD, and provides an overview of possible impacts and their ramifications tostakeholders such as mining companies, the public and governments. The chapterthen presents a technical description of ARD generation, including ARD sources,the sulfide oxidation process and its reaction products, neutralization processesand the factors that affect migration of ARD. Prediction of mine water quality is acritical component of ARD management, and is discussed in Chapter 5. Following

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a generic overview of prediction objectives and approach, data needs andprediction tools are presented, with a focus on geochemical characterizationmethods and geochemical modeling. Additional topics briefly illustrated includeother types of modeling (i.e., statistical, hydrogeological, hydrological, gastransport and risk), as well as discussions of uncertainty and limitationsassociated with mine water quality prediction.

3:45 PM

Characterization and Monitoring Chapters in the GARD Guide

C. Ross; Golder Associates, Inc., Redmond, WA

The GARD Guide discusses Characterization and Monitoring, in chapters 4 and8, respectively. Chapter 4 describes the approach and methods applied to

characterize the release, transport and fate of constituents present in minedrainage. Integration of expertise from numerous disciplines (i.e., geology,hydrology, hydrogeology, geochemistry, biology, meteorology and engineering), tocharacterize sources of mine drainage and the pathways and receptors within themine’s watershed, is discussed. The activities performed during each mine phaseare described. Chapter 8 presents the development of a monitoring programintended to detect environmental changes from mining activities and to assessimpacts to receptors. The chapter discusses the importance of defining clearobjectives at the start of the monitoring program. Data collection and managementactivities associated with source, pathway and receptor monitoring are described.

4:05 PM

The Global Acid Rock Drainage Guide - Prevention and

Mitigation

W. Wilson1 and B. Wickland2; 1Mining Engineerin, University of BritishColumbia, Vancouver, BC, Canada and 2Golder Associates, Inc,

Burnaby, BC, Canada

The objective of this paper is to outline methods for “Best Practice” used in theprevention and mitigation of ARD, NMD and SD from mine waste deposits, openpits and underground facilities. The primary strategic objective for prevention andmitigation is to minimize reaction rates, leaching, conditions and the subsequentmigration of weathering products to the lowest practical levels possible. Key topicsaddressed within the paper for both prevention and mitigation include: i)Segregation, blending and co-disposal; ii) Additions and amendments; iii) Watermanagement including flooding, hydrodynamic containment and seals; iv) Drycovers using synthetics, soils, alkaline and organic materials; and v) Water coverswith subaqueous disposal, wetland covers and partial water covers. Theapplication of each of the methods above is also discussed in a strategic contextfor use within the Global Acid Rock Drainage Guide.

Geology: Geotechnical Engineering and Mine Design II


Chair: R. Pratt, Call & Nicholas , Inc., Tucson, AZ

2:05 PM

Rock Mechanics Tests; Application, and Limitation

H. Nazeri and C. Wienecke; Advanced Terra Testing, Inc.,Lakewood, CO

During the last 60 years, we have seen extensive developments in rockmechanics and its applications due to growing demands for oil, gas, coal, ore,and transportation systems. Numerical methods, in 2D/ 3D version allowingcomplex rock mechanics problems to be studied parametrically within seconds.However, questions about how the rock mass truly behaves for specific designpurposes, regarding rock physical properties involving in situ and/or laboratory

testing data, are often overlooked, due to shortage in budget, schedule, or lackof comprehensive knowledge of rock mechanics. This has often forced theengineer to perform design work while lacking adequate and reliable, high qualitytest data. Often, input information for parametric analyses or engineering designare taken from non reliable literature references, or simply estimated, when noinformation was available at all. In this paper, the authors are attempting to raiseawareness about these issues, by defining the limitations and areas of applicationfor some major rock mechanics tests, as well as to present some real world,common misapplications of rock mechanics test results in mining and civilengineering projects.

2:25 PM

3-D Slope Stability Effects on Leach Pads and Tailings Dams

G. Inci; URS Corporation, Denver, CO

Generally, for stability and seepage analysis of the tailings dam, the model isassumed to be in plane strain conditions. Plane strain is a slice of unit thickness

of a structure in which strain components zz, yz, and zx are zero. However, ifthe structure is partially rotated about an axis such as the corners of a leach pador a tailings impoundment, an axisymmetric assumption would be morerepresentative. In the realm of finite element calculations, plane strain andaxisymmetry have different iterative solutions. The objective of this study is toquantify the 3-D stability effects on leach pads and tailings dams. Specifically, a3-dimensional problem was simplified to two dimensions with plain stain andaxisymmetry models. Seepage and stability analyses were performed for theslopes. Results indicate that axisymmetry and plain strain are less critical andmore critical in terms of seepage and exit gradients. On the other hand, plainstrain has lower factor of safety values for slope stability than those of theaxisymmetric model.

2:45 PM

A Case Study on Failures of Paste Fill Barricades in Blind

Longhole Stopes

M. Yumlu; AMC Consultants Pty Ltd, Melbourne, VIC, Australia

Paste backfill is an engineered high density non-Newtonian slurry made fromsingle or a combination of several suitable solid materials mixed with a presetamount of binder and produced to a toothpaste consistency. Paste is deliveredunderground through surface boreholes by gravity or pumping and reticulatedunderground using a network of internal boreholes and pipelines. Upon completionof ore production, barricades (also known as bulkheads, fill fence, fill walls orretaining walls) are constructed at the draw points of open stopes to contain pastefill while the initial pour cures and forms a plug. Mobilisation of uncured paste fillas a result of a barricade failure is a potential safety hazard and can lead tosignificant consequences, including endangering the safety of personnel, propertydamage and production losses and delays. This paper presents a case study onthree paste fill barricade failures in an underground base metal mine. Details ofthese failures along with their back analysis and the subsequent changes made in

the barricade design and fill placement are presented.

3:05 PM

Nature of the Immediate Floor Rocks in the Illinois Basin

Underground Coal Mines

M. Gadde; Peabody Energy, St Louis, MO

The immediate floor bed in the Illinois basin coal mines is often comprised ofweak, plastic underclay material. Several ground control problems wereencountered in the past due to the variable strength characteristics of theunderclay floor. While some useful and interesting studies were conducted in thepast, within the knowledge of the author, a comprehensive database describingthe engineering characteristics of the underclay has never been published before.In this paper, a large database comprising several engineering properties of thefloor material was put together from a number of active and inactive mines fromall three states covering the basin. Analysis of this data shows some interesting

trends related to the engineering behavior of the floor material. The paper alsodescribes the practical implications of the trends shown by the data.

3:25 PM

Design and Construction of Retaining Structures at Round

Mountain Mine

O. MacIntosh1 and V. Loftus2; 1Collins Engineers, Inc., Auburn, CAand 2Round Mtn Gold Corporation, Round Mountain, NV

The Round Mountain Mine is 60 miles north of Tonopah, Nevada has beenproducing gold since 1988. The mine owner, Round Mountain Gold Corporationdecided to relocate the primary crusher facility 1000’ to make room for the nextphase of open pit mining activities. The mine owner selected Hilfiker RetainingWalls and Collins Engineers, Inc. to provide design and materials for the 56’ highmechanically stabilized embankment (MSE) wall to support the haul trucks. Theconstruction contractor is EarthTech of Norwood,Colorado. The existing facility isa log crib retaining wall and dump pocket which was installed in 1988. The basicdesign of an MSE wall with a cast in place concrete face with steel armor waschosen as a durable yet less expensive alternative to a reinforced concrete dumppocket which was originally designed for the project. The new installation wasdesigned to meet a variety of operation and maintenance requirements. Thedesign emulates the existing facility components that were developed over theyears to meet those requirements. This paper will outline the selection process,design and construction of the MSE wall.

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BE A SPONSOR









you to attend the session: Bridging the Gap, delivered by Gordon Melvin, GlobalDirector, Mincom. Gordon will discuss the complexities of good productionaccounting but will suggest how it can be done to provide significant benefits inbetter managing any mining company.

2:25 PM

Analysis of Sampling and Slurry Flow Using Multi-Physics

Modeling

D. McBride1, M. Cross1 and J. Gebhardt2; 1School of Engineering,Swansea University, Swansea, United Kingdom and 2ProcessEngineering Resources Inc, Salt Lake City, UT

Representative samples are required from process streams in order to accuratelymeasure chemical and physical characteristics. This information can then be usedby process operators and metallurgists to evaluate the process and affect controlactions for the operation. The capture and presentation of representative samplescan be critical to measuring values, such as elemental analysis and particle size,with on-line or near-stream analyzers. A comprehensive multi-physics model hasbeen developed and used to better understand the effects of slurry flow andparticle segregation under cer tain operating parameters. An algebraic slip modelcoupled with a free surface algorithm is used to track motion and position ofparticles and phases within a specified geometry.

2:45 PM

Utilizing Efficient Classification Technology to Increase Grinding

Productivity for the Worlds Largest Iron Ore Producer

D. Switzer1 and R. Petroni2; 1Weir Minerals North America, Madison,WI and 2Weir Minerals Brasil, São Paulo, Brazil

Test work was carried out by Nabrisco-Vale and Weir Minerals to quantify thetheoretical benefits of improving hydrocyclone efficiency and its impact on thecapacity of the iron ore grinding circuit. The test consisted of using higherefficiency hydrocyclones installed in closed circuit with the ball mill. Within the first40 days of the test period, productivity was increased by approximately 6 percent.Three cyclone clusters were then changed out after the test. Translating thisincreased capacity across the circuit results in an additional 277,383 tons ofpellets produced per year.

3:05 PM

Utilizing Six Sigma to Design Blasting Operations for Optimum

Mill Performance at Cleveland-Cliffs Michigan Operations

A. Koski; Cleveland-Cliffs Michigan Operations, Ishpeming, MI

In early 2008, Michigan Operations formed a Six Sigma Mine to Mill Team to fullyunderstand the relationships between blasting and downstream crushing and

grinding operations. The team focused on the identification of optimum mill feedto provide blast design fragmentation goals. This paper describes the ongoingteam efforts of a Six Sigma Master Black Belt, an ore control geologist, two plantmetallurgists and a drilling and blasting engineer to improve mill throughput andreduce costs. Proper size distribution is critical for autogenous milling to optimizefeed rates and mill throughput. Evaluating blasts for good fragmentation andefficient loading does not provide the information required to determine whethera blast is optimally designed. Blasting is only the first step in an integratedcomminution process that leads from low grade iron ore to high quality pellets.Blast design must include an understanding of its influence on costs andproductivity for the processing steps that follow after loading, hauling and primarycrushing. Blasting must be designed and optimized to obtain the lowest overallcosts or the highest operating profit.

3:25 PM

Modelling Liberation Characteristics of Comminuted Particles

E. Wightman and C. Evans; Julius Kruttschnitt Mineral ResearchCentre, Indooroopilly, QLD, Australia

One of the challenges in the development of mineral processing simulators ismodelling the liberation characteristics of particles produced by comminutioncircuits. Understanding the mineral characteristics of these particles is one of thekeys to predicting their behaviour in separation circuits. While more fundamentalresearch seeks to model the non-random breakage of ores this work examineswhether we can move forward now by using observed characteristics of ores tomodel the composition of particles generated in comminution processes. Thecurrent work examines a range of ores and identifies which exhibit the pattern ofsimilarity of composition for particles in a given size class that has been producedas the result of a variety of breakage conditions. The impact of mineralogy andtexture on the evolution of liberation characteristics for both valuable and gangueminerals is discussed.

Mining & Exploration: Managing for Sustainability in theMinerals Industry


Chairs: J. Botin, Universidad Politecnica, Madrid, Madrid

A. Rodriguez-Avello, Madrid School of Mines, Madrid, Madrid

2:05 PM

Sustainable Management of Mining Operations: An Overview

J. Botin; Explotacion de Minas, Universidad Politecnica, Madrid, SpainThe use of mineral resources has been fundamental to human activity; fromhousing to household goods, from industrial equipment to energy and from hightechnology to space exploration, mining has provided the basis of life to thehuman race. As important as these benefits are, mining activity causes social andenvironmental impacts on communities that require a more responsible miningpractice – it requires “Sustainable Mine Management”. Many mining companieshave acknowledged the challenge and have stated their commitment to the valuesof sustainability. However, the public perception of the environmental and socialperformance of the minerals industry remains poor. In this context miningmanagers are expected to not only comply but lead in the development ofincreasingly demanding corporate policies and regulations for environmentalcontrol, safety and social responsibility. This presentation provides an overview ofthe concept of sustainable management as the management approach thatintegrates sustainability across the organization of the company.

2:15 PM

Sustainability, Sustainable Development, and What They Meanfor Mineral Development and Management

R. Eggert; Colorado School of Mines, Golden, CO

Despite the prominence of sustainability and sustainable development in currentdiscussions about mining, these terms are prone to hyperbole, confusion, anddisagreement over what they mean and imply for mining. This talk seeks to clarifythe concepts of sustainability and sustainable development and what they implyfor mine management. It begins by reviewing the ideas behind sustainability andsustainable development, independent of mineral development and mining. It thendefines four implications (or principles) for the mineral sector and discusses whatthey mean for the responsibilities of mining companies. Finally, it reviews whatcompanies have done to put these principles into practice and what project-leveltools have been developed to guide mine managers.

2:35 PM

Sustainable Management of Mineral processing PlantsA. Rodriguez-Avello; Materials Engineering, Madrid School of Mines,Madrid, Spain

Mineral processing may be described by a multistage process starting from oreliberation by comminution to concentration of the values and subsequent disposalof the tailings. Sustainable management of the processing plant is aimed mainlyby increasing efficiency of the unit operations and reduced energy consumption,together with responsible compliance of the local environmental laws and safetyand health regulations. To achieve this goal, it must be put in practice theoptimization of mine/mill interface,crushing and grinding circuits, efficient selectionof screens and classification systems, economic ore concentration and safetydisposal of tailings . Mill motors efficiency is critical for energy savings. Labortraining and predictive maintenance programs can improve productivity.International safety and health regulations should be implemented for bestrelationship with working forces and authorities.

2:54 PM

Mine Planning and Sustainability

G. Davis; Division of Economics and Business, Colorado School ofMines, Golden, CO

The word sustainability can have many meanings and interpretations, and therecan be considerable discord over how mining should be viewed within thesevarious interpretations. One view of sustainability, however, is incontrovertible,and that is the view that finite resources, if they are to be extracted, should beextracted efficiently. Efficiency means that society should recover maximum valuefrom the mined resource through its extraction. Mine planning and feasibilityanalysis, to the extent that it is aimed at design and extraction decisions thatmaximize the value of the mine, is exactly in line with efficiency. If mine planningand feasibility analysis is not done well, or could be improved, sustainability canbe improved. This paper discusses mine planning with particular reference tosustainability, and how a new planning and evaluation technique, called realoptions, improves upon traditional NPV analysis as a means of efficientlydesigning and managing mining projects.

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3:14 PM

Partnerships for Sustainable Development in Ghana: Integration

of Leading Practice in the Design and Implementation of

Sustainable Development Programs at the Tarkwa and Damang

Gold Mines in Ghana

T. Aubynn; Corporate Affairs and Social Development, Gold FieldsGhana, Airport, Accra, Ghana

A key challenge that confronts many mining companies operating in developingcountries is how to maximize the effectiveness of, and return on investment fromtheir sustainable development programs. In the past many mining companies’social responsibility efforts have been primarily aimed at enhancing public

infrastructure in communities where they are located, with a focus on education,water and sanitation, and health. The sustainability of the infrastructure and/or itsfunction has been at risk due to insufficient capacity in beneficiary communitiesand local government to manage and maintain them. This situation has oftencreated the risk of permanent and un-sustainable dependence upon companyresources. This paper utilizes a case study of Gold Fields Ghana (GFG) todescribe the various components of a successful strategy designed to maximizethe effectiveness of corporate sustainable development programs. The GFG modelrepresents a leading example of best practice in the international mining industryfor community engagement and sustainable development.

3:33 PM

Human Resources Management

L. Freeman1 and H. Miller2; 1Downing Teal Inc., Denver, CO and2Colorado School of Mines, Golden, CO

The effective management of human resources, including employee recruitmentand development, is as critical to the long-term success and economic viability ofa mining company as is the development of new orebodies and exploration targets.While the impact of labor productivity and cost have long been a major focus ofmanagement, the traditional philosophies engrained in the mining industry towardhuman resources and workforce issues have recently undergone substantialchange. Many believe this transformation is symptomatic of changes in employeeattitudes and the daunting challenges facing mining companies as a consequenceof a shrinking talent pool, government regulation, community/social expectations,and rapidly increasing skill competencies required of today’s miner. The primarytheme of this talk is to present topics which are fundamental to the creation of acorporate culture that promotes the productive utilization of human resources andthe development of sustainable business practices that produce tangible benefitsfor the company, employees, and the communities in which they operate.

3:53 PM

Sustainability of Rock Fragmentation by Blasting

B. Cebrian; Blast Consult S.L., Madrid, SpainRock blasting is the most efficient technique for fragmentation of a wide variety ofrock masses, especially in very hard to medium hardness formations. Because ofthe explosives huge delivery of power, there are factors to take into account inorder to maintain blasting as a feasible option over time. Main issues with blastingare safety for workers, bystanders and equipment and environmental effects dueto airblast, flyrock and ground vibrations. Safety in blasting is mainly related togood practices in planning, loading and shooting a blast. All steps have to insurethat no risks are taken when manipulating explosives or shooting them in a certainarea. Environmental effects of blasting require a good assessment of each specificoperation in which the goal of rock fragmentation has to be combined withminimum disturbance of the surrounding areas (sometimes up to few miles).Atmospheric conditions and site-specific geology play a key role in the mainenvironmental effects of rock blasting. Finding and controlling a few keyparameters of the effects of blasting in the surroundings can make the differencebetween keeping this cheap rock fragmentation system running or not.

4:12 PMStrategy and Sustainability in Mining Companies

J. Rebollo; Economics & Business, Colorado School of Mines,Golden, CO

The increasing weight that social and environmental factors are taking in theMining and Metals Industry, as well as the challenges brought by globalization, areforcing companies to rethink their strategies from a totally new perspective.Designing a modern company’s strategy includes a continuous redefinition of itsbusiness geometry: its size, markets, geographical implementation, technologiesand human resources, as well as its social and political attitude and interfaces. Thelegal frame under which the mining activities take place continues as an importantlimitation. However, the social, environmental and sustainability aspects areincreasingly taking a predominant strategic role. Obtaining what has been calledthe “social license to operate” becomes today the main challenge for companies.This presentation summarizes the chapter “Strategic Management in the MineralsIndustry” of the book “Sustainable Management of Mining Operations”. It develops

the basic concepts of modern business strategy with consideration to thespecificities of the Mining Industry and analyzes the external and internal factorsthat provide the framework of the most successful strategies.

4:32 PM

Sustainable Management of Large Volume Mined Materials

D. Van Zyl; Norman B. Keevil Institute of Mining Engineering,University of British Columbia, Vancouver, BC, Canada

The volumes of mined materials increase on an annual basis as more mines operateat higher production rates. These materials include mined rock, tailings and heapleach spent ore and they have largely different physical and chemical characteristicsthat must be understood and incorporated in the management of the resultingfacilities. New landforms are created through the placement of these minedmaterials. The mining industry, designers and operators have large responsibilitiesto develop sustainable management strategies for these materials and the resultinglandforms. Sustainable management strategies for large volume mined materialsinclude economic, environment, community and governance demands.

Mining & Exploration: New Equipment Advances


Chair: J.Humphrey, Caterpil lar, Decatur, IL

2:05 PM

Slow Speed Object Detection for Haul TrucksS. Stark; Caterpillar, Inc., Mossville, IL

A need for better operator awareness of their surroundings has been growing formany years. While existing products, such as closed circuit television systems,provide better awareness than direct observation, they still rely on the operator toconsistently use the system. A more active approach is needed to make theoperator aware of the presence of objects in their immediate surroundings. Thisis especially important when the machine has been parked for a period of time andthe operator needs to start moving the truck again. This paper will coverCaterpillar’s solution to provide an integrated active detection and warning systemfor haul truck applications. Topics to be covered include the research that wentinto developing the system, discussion of technologies used in the system, andfeatures of the system.

2:25 PM

Design and Preliminary Testing of Low-Energy Planetary

Excavator

J. Rostami, L. Gertsch, R. Gustafson and C. Swope; Energy andMineral Engineering, Pennsylvania State Univ., University Park, PA

Any mining and construction activities on the Moon can only be performed by arobust excavation machine that can excavate a variety of material from loosesurface regolith to consolidated (frozen) soil with embedded rocks in the mixture.A Low-Energy Planetary Excavator is being developed under an ORBITEC PhaseII SBIR project funded by the NASA Kennedy Space Center. A prototypecutterhead for the excavator was built and tested at the Kennametal facility inLatrobe PA. This paper discusses the results of tests performed on compactedlunar regolith simulant to characterize the potential range of material propertiesthat may be encountered on the Moon, including frozen regolith that may existwithin permanently shadowed craters. The results of force-indentation tests andunconfined compressive strength measurements will be presented, along withdiscussion of the cutting forces required for mechanical excavation of the regolith.A brief review of the testing of the prototype cutterhead in various materials will be

offered along with production rates estimates under various assumed groundconditions.

2:45 PM

Discussion of Performance Modeling as it Relates to Mining

Truck Drive Systems: Do Advances In Drive Systems Require

Modeling Adjustments?

M. Richards; Heavy Construction & Mining Division, Caterpillar Inc.,Decatur, IL

In the past decades there have been significant changes in mining truck drivesystem technology, with trucks evolving from DC-electric drive to the currentselection of mechanical and electric drive systems. This paper will discuss whatconsiderations need to be taken into account to accurately model mining truckperformance given this evolution. Key to this discussion is an understanding ofthe differences in operation of electric and mechanical dr ive trucks and how these



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differences impact performance modeling. This paper will not attempt to endorsea specific modeling tool, but will acknowledge that modeling tools may need to beadjusted to ensure accurate representation of truck performance given a specificdrive system. The paper will also discuss accurate modeling of truck brakingperformance given the types of systems currently in use, including dry and wetbrakes and differences in continuous versus dynamic retarding. By taking intoaccount the correct factors when modeling truck performance and ensuring thatevaluation tools accurately differentiate between truck features and drive systems,it is possible to closely predict mining truck performance in the field.

3:05 PM

Operator Fatigue in Large Mining Trucks: An Objective Review

and Driving Simulation Examination of Fatigue Monitoring

Technologies

D. Edwards; Product Safety & Compliance Division, Caterpillar Inc.,Peoria, IL

In the mining industry over 90% of earth moving equipment accidents are due tooperator error. Drowsiness decreases operator awareness and increases theirmental and motor reaction time impairing operator judgment much like alcohol.Drowsy drivers are often unaware of their condition, frequently driving for 3-30seconds with eyes totally closed. Operators falling asleep behind the wheel havebeen identified as a prevalent root cause of accidents involving large mining trucks.Although operator fatigue is predominantly a people and shift management issue,companies are looking to technology for assistance with this problem. This studyprovides an unbiased review of 22 technologies by a panel of experts from thefatigue and mining industries using an objective evaluation method. Expertsscored each technology on its functional capabilities in general as well as howthe technology met mining industry requirements. Select technologies were thenused in a driving simulation study of sleep-deprived individuals in order to

determine the potential of these technologies to reduce the likelihood of fatiguerelated driving accidents.

3:25 PM

Simulation In Mining

V. Hopkins; ThoroughTec, Durban, South Africa

Since the rise of the Roman Empire to the landing of space missions, simulationhas played a large part of our reality, helping to mould, optimize and improve theutilisation of modern equipment. From a simple car to an advanced space shuttle,simulation improves efficiency, effectiveness and safety whilst at the same timereducing training costs and time.

3:45 PM

Leveraging Mine Resources through Solid Technological

Advancements in Mining Shovels

T. Barnes; Product Management, P&H Mining Equipment,Milwaukee, WI

It may seem like yesterday, but it has been ten years since 100 ton class shovelsstarted laboring in surface mines around the world. The performance of 100 ton andother class shovels has steadily improved to keep up with advances in haul trucks,resulting in better cost per ton. However, there are technology developments thatcarry an even greater impact on surface mining operations’ profitability. Solidadvances in ergonomics, communication, automation, and control technology forshovels are helping mines address growing resource management challenges,improve predictability, and adopt new material movement technologies such asautonomous trucks and integrated in-pit crushing and conveying systems. Theaudience will hear a brief overview of the technology currently deployed on shovels,and also a preview of new developments. We will all leave with an understandingthat the next ten years, while using the same shovels, trucks, and in-pit crush andconvey systems, will not look like the first ten years.

4:05 PM

New Advances in Lowboy and Tow Truck Technology

K. Henderson; TowHaul Corporation, Belgrade, MT

During the past 3 years, significant design improvements and technologies havegreatly impacted both the maintenance and operation of off road lowboys and towtrucks on a mine site. The ability to use a wet disk brake axle on a front loadinglowboy has reduced lowboy axle maintenance and increased retarding capability.Utilizing a wet disk brake axle has been inhibited in the past due to contaminationconcerns in the hydraulic system. The new patented TowHaul Brake CoolingPackage circulates and cools the brake oil in a self contained system via theforward rotation of the lowboy tires. Modular construction of large capacity lowboyshas allowed lowboys to be shipped to remote mines throughout the world withlimited on-site construction time. In addition to reduced construction and shippingcosts, the modular sections make repair and/or replacement of lowboy sectionseasy to facilitate. TowHaul has developed and patented a Park Brake ReleaseSystem for use when towing disabled haul trucks. The TowHaul Park Brake

Release System utilizes the Prime Mover to pressurize and release the parkbrakes on disabled haul trucks, from inside the cab of the Prime Mover.

4:25 PM

Hydraulic Crowd Drives Increased Production Uptime

R. Haws1 and D. Lang2; 1Product Marketing, Bucyrus International,Inc., South Milwaukee, WY and 2Shovel Engineering, BucyrusInternational, Inc, South Milwaukee, WI

An alternative crowd mechanism has been developed by Bucyrus International toreplace traditional rope and rack and pinion crowd machinery on Electric MiningShovels. This paper demonstrates that a shovel equipped with Hydraulic Crowdwill have a planned major maintenance interval of two years or 12,000 hours. Itoffers the advantage of increased machine reliability and uptime. The need tochange ropes 8 to 12 times per year and the need to change rack and pinioncomponents annually are eliminated. The increased production uptime from thisavailability increase, coupled with reduced shock loading, translates into significantproductivity gains, which contributes directly to decreased unit cost for theoperation. A hydraulic assembly and power pack replaces ropes, a drum, andconventional gear box in the rope crowd shovel. The power pack is located on therevolving frame deck in the same location as the conventional gear box on a ropecrowd shovel. The power pack is driven by a 700 horsepower motor controlled bythe AC-IGBT drive system. The orientation of the power pack in the machineryhouse makes it easy and safe to maintain.

4:45 PM

The Power of One, Changing the World One Truck at a Time

D. Lindell1 and N. Rutter2; 1Komatsu, Peoria, IL and 2Komatsu,Peoria, IL

When a dust storm in Mongolia can change the sunset in California and rainshowers in the African desert can turn into Caribbean hurricanes, we must cometo the conclusion that the choices we make about what is exhausted into theatmosphere can have a measurable impact on the rest of the world. This paperinvestigates the potential benefits of on-board and off-board technologiesdesigned to reduce carbon emissions and fuel consumption for haulageequipment. Beyond the cliché, what investments and benefits are to be found bychoosing to lead the change and where can you start?

5:05 PM

Analysis of Light Elements in Earth Materials Using Handheld

X-ray Fluorescence

L. Stupi; NITON Analyzers, Thermo Fisher Scientific, San Jose, CA

Users of handheld X-ray Fluorescence (XRF) analyzers in the mining communityhave focused on analytes such as Fe, Cu, Ag, Pb, REE’s, and other relatively

heavy elements. The recent development of He purge and multi-filter instrumentshave advanced handheld XRF instrumentation to allow the user to analyze lighterelements such as S, P, Ca, Si, and Al with improved detection limits and accuracyin the field or in the lab. Although the best results from handheld XRF technologyare achieved by performing proper sample preparation, the extent of preparationneeded varies by project. For bench top XRF analysis sample preparation requiresdrying, grinding, mixing, and pressing into pellets or melting into discs; all samplesmust be of uniform dimensions. For handheld XRF, satisfactory results areachieved with much less work and without uniform samples. We have attainedcorrelation coefficients of 0.94-0.99 for some elements, and the results fromcorrelation studies between handheld XRF and laboratory analysis for P, S, Ca, Si,and Al will be discussed. The data demonstrates cases that required varyingamounts of sample preparation to meet the data quality objectives of the project.

Mining & Exploration: Surface and Open Pit Mining /Production Optimization


Chair: D. Cooke, Freeport McMoRan Copper & Gold Sierrita

Operations, Green Valley, AZ

2:00 PM

Estimating Excavator Teeth Consumption Rates

C. Roos1, P. Conrad1 and S. Rosenthal2; 1Mining Engineering,Montana Tech, Butte, MT and 2Newmont Mining Corp.,Englewood, CO

Ground engaging tools are used to prevent damage to the main components ofearth-moving equipment. These tools consist of everything from shovel teeth toreplaceable drill bits to dozer wear plates. The costs of these “consumable” itemsare increasing with the costs of raw materials. This project developed a tool to be



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used by Newmont Mining Corporation to predict the consumption of excavatorteeth. This paper presents the results of a Montana Tech research project in whichan equation was developed to predict excavator teeth consumption based onproduction rates and rock properties.

2:17 PM

Mine Planning – Beginning with the End in Mind Rosemont

Copper Company

R. Pace; Rosemont Copper Company, Tucson, AZ

Rosemont Copper Company started its permitting and planning in the UnitedStates in the 21st Century. This simple fact makes mine planning at Rosemontunique because the public is savvier and the requirements are more stringent thanthey were a mere thirty years ago. Mine planning will have to incorporate the notonly production, safety, productivity, and profitability but will also have to look atwater conservation, reclamation, visual resources, and post-mining land uses.Rosemont is also in an unusual position because we will have to becometemporary stewards of the public lands and manage these public lands in a waythat will leave behind an asset for the public. The planned mining operations atRosemont will require mining 75,000 tons of sulfide ore, 15,000 tons of oxide ore,and 250,000 tons of waste mater ial a day. This will result in an annual productionof 220 million pounds of copper concentrates, 15 million pounds of coppercathode, 4.5 million pounds of molybdenum, 2.6 million ounces of silver, and 15thousand ounces of gold per year.

2:34 PM

Decision Support Systems for Multi-Mine Material Blending

Optimization

P. Orr; Gemcom Software, Vancouver, BC, Canada

Among the mining industry segments facing multi-mine blending problems areiron ore, coal and bauxite mining. There are mathematical reasons why manyproblems are fundamentally hard to solve well, and these mathematics governthe material blend challenge. Fast Cycle Optimization is a decision-support systemthat enables operators to respond to unplanned disruptions in the supply chain.Fast Cycle Optimization, the main focus of this research, requires the designfeedback loop in which data from production, logistics and maintenance systemsthroughout the supply chain and fed into a fast-cycle optimization engine. The fast-cycle optimization engine enables operators to select the best availableconfiguration of assets in response to disruptions based on user-defined priorities(e.g. optimize on on-time delivery, then cost). The paper presents results of aresearch project on next generation decision support tools for multi-mine materialblending. Results focus on three aspects: a) Blending optimization that can handleuncertainty and disruption b) Logistics and dynamic resource allocation c)Dynamic Inventory Management.

2:51 PM

A New Short- And Medium-Term Production Scheduling Tool –

MineSight® Schedule Optimizer

Z. Huang, W. Cai and F. Banfield; Mintec Inc., Tucson, AZ

The MineSight® Schedule Optimizer (MSSO) is a new production scheduling tooldeveloped by Mintec Inc. using mixed integer linear programming (MILP)techniques. This package was developed to solve short- and medium-termschedule problems for surface and underground mining operations that involvemultiple models, waste dumps, leach pads, stockpiles, mills or processes andblending requirements. MSSO finds the optimum schedule in each period thatachieves the objective while satisfying comprehensive product quality and quantityrequirements as well as physical and technical constraints. Using MineSight® Attributed Geometry Data Model (AGDM) as a central database, MSSO seamlesslyworks with MineSight® 3D (MS3D) block models and third-party data, MineSight® Interactive Planner (MSIP), MineSight® Haulage (MSH) and MineSight® ActivityPlanner (MSAP) in data preparation, MILP model formulation, schedule calculation,report, fine-tuning, saving and visualization. This paper will present the techniques

and mathematics utilized in MSSO. A case study will also be given to demonstratethe applications and capacities of this new scheduling tool.

3:08 PM

Remote Asset Monitoring Process

M. Lowery; FMA Maintenance Organization, Freeport McMoRanCopper & Gold, Safford, AZ

Monitoring of machine data on mobile mining equipment is being conducted atmost of the Freeport McMoRan Copper and Gold’s open pit mine sites in NorthAmerica. The Remote Asset Monitoring Process (RAMP) evaluates near real timeequipment health data on Caterpillar 793 haul trucks, P&H 4100 & 2800 electricshovels and some Caterpillar support equipment. Continuous monitoring isaccomplished with remote capabilities between sites. OEM & user-defined eventsare watched by fleet coordinators in order to avoid catastrophic or prematurefailures and to increase equipment capability and reliability. Important reduction ofmaintenance and/or operator induced events has been realized.

3:25 PM

Haul Road Design & Maintenance and Payloads Role in

Production Optimisation

C. Davis; Global Mining, Caterpillar, Peoria, IL

The following paper will explore methodology’s for Optimising haulage fleetproductivity and cost, through the management of the following variables 1. HaulRoad design 2. Haul Road Maintenance 3. and Payload management. With eachof these variables it is intended to work through examples on how the variationcould be identified and quantify impact on productivity or cost. Whilst the individualexamples will not be applicable to all applications the method for obtaining thedata and developing the theoretical alternatives to enable the assessment of thepotential gain should be applicable on all haulage applications.The discussion will

focus on tools and onboard technologies that are available today in conductingoptimization studies.

3:42 PM

Tire Life Improvement

H. Wilson; Freeport-McMoRan, Phoenix, AZ

This paper will cover the effort of two Freeport-Mcmoran America’s QualityAnalysts’ work with data, a global team, various vendors and support groupsimproving tire life across our North and South America operations.

3:59 PM

Short-term Dynamic Mining Optimization with Sequencing and

Blending Constrains at Red Dog Zinc-Lead Open Pit Mine

H. Li, P. Norman and F. Pillifant; Mining, Teckcominco Alaska,

Anchorage, AK

A dynamic production optimization model with mine cuts sequencing and stockpileblending constrains is developed to schedule weekly production in one quarterperiod for Red Dog Zinc-Lead Mine. The model is based on the algorithm of mixedinteger linear programming (MILP) to sequence the mining activity, and to balanceand stabilize the grade and other mill constrains. There are 25~30 cuts which takesplace in three to four relatively detached area in the main pit are mined to build sixstockpiles every quarter. There is very high fluctuation of grades between the cutsand in each cut as well. Mill gives the tonnage and grade constrains once a year.Current blending limits on mill feed are: Zn/Fe ratio ≥2.50, Zn/Pb ratio ≥3.50,Zn/TOC ratio ≥24.5, and TOC ≤0.80%. The optimization model is completed inMS Excel using Lindo spreadsheet solver add-in for real-time updating. Not onlythe tremendous workload released for the engineers and grade control geologists,but the best optimization of grad control obtained as well. The fluctuation of Zn/Pbratio between the stockpiles drops to 4.1% in 3rd quarter from 15% in 2nd quarterwith the use of the model.

4:16 PM

Development of Truck Allocation Model for Truck Dispatching in

Open Pit Mining Operations

K. Dagdelen1, S. Artittong1 and C. Gurgur2; 1Mining EngineeringDepartment, Colorado School of Mines, Golden, CO and 2Division ofEconomics and Business, Colorado School of Mines, Golden, CO

In recent years, there has been considerable research and commercial softwaredevelopment providing efficient tools or methods that would give the optimized longand short term plans for open pit mines while considering complex miningoperational constraints. However, the existing truck allocation optimization modelsare set up to satisfy the requirements of loading units on a single time period basiswithout consideration of the multi period mine production requirements. This paperwill describe the Linear Programming (LP) based approach for truck allocationoptimization by minimizing production variations from planned production targets.The Mixed Integer Programming (MIP) based approach may be used for long andshort term planning. Then, the LP based approach can be used for truck allocationto synchronize the actual material movement under the existence of the complexitiesof mining operations to the scheduled mine plans. This paper will discuss this newlyproposed method and its implementation on a realistic case study.

Photo by Bob Ashe, Denver Metro Convention & Visitors Bureau





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challenges which are being researched. X-ray diffraction, automated mineralogy,and chemical analyses have been conducted to evaluate the minerals for use in theanimal feed industry, fillers in plastics and paints, fertilizers and roofing products.

2:45 PM

Developing a New Process Design for the Southwestern Oregon

Industrial Mineral Bearing Placer System via Practical Study of

the Unique Deposition, Mineralogy, and Dry Tailing Requirements

J. Drew and T. Lessard; Oregon Resources Corporation, Coos Bay, OR

Initial study relating to the deposition, mineralogy, and logistical requirements ofa unique industrial mineral bearing placer system in southwestern Oregon has

led Oregon Resources Corporation (ORC) to develop new process, mining, andreclamation designs that will maximize the overall success of the project. Theplacer deposits are tectonically acted upon, leading to deposition that is relativelyvariable in terms of heavy mineral grade and mineralogy. Material handling andwet/dry processing were designed to allow for flexibility that produces consistentquality and quantity of chromite foundry sand, garnet and zircon. Ore will betrucked approximately twenty miles to be processed where water, electricity, andnatural gas are readily available. Dewatering of the tailings ensures low processwater requirements and prevents water leakage from trucks returning with tails tothe mine site. Dewatering tailings at the process site also eliminates the need toconstruct pond systems for mine site reclamation. ORC intends to have thereclamation efforts follow immediately behind the mining activities within the samepit, keeping the working footprint of the mine site very small.

3:05 PM

Effects of Mineral Chemistry and Textures on Processing at the

Tilden Hematite Deposit, Marquette Range, Michigan

G. Scott, H. Lukey and J. Lubben; Cliffs Technology Group, CliffsMining Service Company, Ispeming, MI

The Tilden hematite flow sheet is the most complicated iron ore process incommercial operation with very fine grinds, selective deslime and reverse flotationrequired. Ore and gangue mineralogy and liberation characteristics have asignificant impact on plant efficiencies. Mineralogic variation is recognized withinindividual mineral grains; at blast pattern (10 to 15 meter) and development drillhole (100 meter) scales. A simplified stratigraphic column consists of theCarbonate domain (martite-magnetite-various carbonates±silicates) in the coreof the Main Pit anticline overlain by the Martite domain (magnetite-martite+localgoethite) and the Hematite domain (mar tite-microplaty hematite+goethite). Thesecompositional and associated textural variations affect plant efficiency and productquality, and are critical factors for ore reserve modeling, ore control and mineplanning decisions.

3:25 PM

Uses of Helium in Geologic Exploration and Metallurgy

S. Burton, S. Ali and D. Driskill; Amarillo Field Office, Bureau of LandManagement, Amarillo, TX

This paper reviews the current uses of helium in gas geochemistry, mineralexploration, and metallurgy. Some key uses of helium isotopic ratios in theexploration of geohydrology, seismology, volcanology, and geothermal explorationare discussed. These uses provide a framework for generating strategies for theglobal exploration of helium-rich natural gas reservoirs. Additional uses for heliuminclude helium retention on powder metals, metal working processes using helium,and helium uses in electronics manufacturing, advances in gas metal arc welding(GMAW), and metal inert gas (MIG) welding. The principal source of helium iswidely accepted as the steady rate of radioactive decay of uranium (average: 2.8ppm) and thorium (average: 10.7 ppm) found throughout the crust. While He-4flux is largely accounted for by degassing of radiogenic helium from the crust, therare He-3 isotope originates from the mantle where the isotopic composition ofhelium is ~1000 times greater than that found in the Earth’s crust.

3:45 PM

Laboratory Evaluation of Clays Prior to Processing

H. Murray; Geology Department, Indiana University, Bloomington, IN

Clay minerals are one of the more important industr ial minerals. They are used inmany industrial products and because of different specifications may requirespecial processing which can be either wet or dry. The clays discussed arebentonites, kaolins, and palygorskite and sepiolite. In order to design a properprocess flow sheet for each of these clay minerals they need to be analyzed in thelaboratory to evaluate their mineralogical, chemical, physical, and opticalproperties. Each species of clay minerals require a special group of tests which aredescribed in this oral presentation and in the preprinted paper.

4:05 PM

Utilizing Mineral Liberation Analysis (MLA) to Determine Pyrite,

Arsenopyrite and Arsenian Pyrite Floatabilities for Carlin-trend

Ores

R. Kappes, J. Gathje and D. Brosnahan; Newmont Mining Corporation,Englewood, CO

Mineral liberation data is routinely obtained for a wide variety of applications,including ore charaterization and characterization of various metallurgical testproducts obtained in bench-scale laboratory testwork. Newmont MiningCorporation owns several properties in the Carlin-trend containing refractory goldores. These ores are generally difficult to treat and have to undergo several

processing stages for gold recovery. At Carlin’s Mill 5 operation, flotation is usedto pre-concentrate some of these difficult ores to produce a concentrate to feed theroaster. It is of interest from a flotation perspective to be able to study the floatabilityof pyrite, arsenopyrite and arsenian pyrite, since these minerals all have differentquantities of gold associated with them, and have to be recovered to ensure asuccessful separation has been achieved. In this paper, a detailed MLA study onseveral Carlin ores was undertaken on samples from flotation tests, using air ornitrogen as flotation gas, specifically to study the differences in liberation andfloatability charateristics, which ultimately impacts overall gold recovery.

Operators Open Forum

4:00PM • Tuesday, February 24, 2009

Chairs: Jami Dwyer, Barrick Goldstrike Mines, Elko, NV

Don Dwyer, Barrick Goldstrike Mines, Elko, NV

Don’t miss the this Annual event of “technical fun” and comeprepared for anything!

Wednesday, February 25 Morning

Coal & Energy: Coal Bumps and Seismicity

9:00 AM • Wednesday, February 25

Chair: F. Varley, NIOSH, Spokane, WA

9:05 AM

Regional Bumps – Case Studies from the 1958 SME Bump

Symposium

J. Whyatt; Spokane Research Lab, NIOSH, Spokane, WA

Pillar bumps and local outbursts of coal are a concern in many coal mines, andhave received considerable attention from the industry and regulators. Regionaldynamic failures have been much less common. However, these events recur inmining history, much like 50-year floods, often surprising many who have notexperienced such an event. A variety of regional dynamic failure cases weredescribed in a bump symposium sponsored by the SME in 1958 - ironically, just50 years ago at this writing. These cases include regional failure of productionpillars, main haulage-ways, and openings along fault traces – and are attributed todynamic loading of openings induced by failures elsewhere in the rock mass.Bumps resulting from such dynamic or impact loads have often been called shockbumps. Special consideration has to be given to these failures since they are notaddressed by many of the tools commonly used to analyze coal mine plans,including those used to analyze the Crandall collapse. This paper seeks to providea foundation for avoiding future shock bumps by reviewing and updating discussionof historic shock bumps documented in the 1958 SME Bump Symposium.

WADSWORTH LECTURE:


Chair: Corby Anderson, Montana Tech of the University of Montana

“The Fundamentals and Applications of Nitrogen SpeciesCatalyzed Pressure Oxidation and Alkaline Sulfide”



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9:25 AM

Coal Mine Burst Hazard Trend Analysis - 1983 to 2007

A. Iannacchione; Dept. of Civil & Env. Eng., University of Pittsburgh,Pittsburgh, PA

Coal burst risks at underground mining operations are affected by many factorsand are therefore, not equal. Understanding coal burst hazards is a necessaryfirst step towards assessing their risk and determining, if and, when a coal burstbest practice should be used. Trend analysis was made solely on the pastoccurrences of reported burst events and injuries found in the MSHA DataRetrieval System from underground coal mining operations between 1983 and2007. 306 coal mine burst events occurred in 69 mines within five prominent coalmining states including Colorado, Kentucky, Utah, Virginia, and West Virginia. Utah

has the majority of mines (42 %) with coal bursts occurrences. Of the 306 events,129 events did not have associated injuries. Typically, these events would havedisrupted ventilation systems or travel ways within the mine, requiring MSHAnotification. Of the 187 event with injuries, 227 miners were injured from coalbursts between 1983 and 2007, 19 of which were fatalities. A backward lookingrisk characterization was undertaken to measure the rate of coal burstoccurrences and to document their consequence to the mine’s workforce.

10:05 AM

Dynamic Failure in Deep Western Coal Mines: Cases and

Mechanisms

J. Ulery2 and J. Whyatt1; 1NIOSH, Spokane, WA and 2NIOSH,Pittsburgh, PA

Hard brittle coals, massive brittle sandstones and deep cover are encountered inmany deep western coal mines, giving rise to a long history of dynamic failure

events variously described as bumps, bounces, etc. These events vary widely inhazard to miners, impact on mining operations and production of seismic energy.A review of these events found that they fall into a number of different classes.That is, there is not just one coal bump problem, but a variety of problems withcharacteristic mechanisms and relationships to mine geology and operations.Moreover, these classes of events respond differently to bump control efforts.Recognition of particular coal bump mechanisms and the related geologic settingsthat are potentially active at a mine is an important first step towards effectivecontrol, a goal of ongoing research at the National Institute for Occupational Safetyand Health.

10:25 AM

A Review of Support Systems for Bump Prone Coal Mines in the

Western United States

S. Harvey and U. Ozbay; Colorado School of Mines, Golden, CO

In bump-prone coal mines, roof and rib support is subject to dynamic as well asstatic loading. Yielding support systems in many deep mining sectors, especiallydeep mining of precious metals, are explicitly designed to protect miners fromdynamic failure. This paper examines the use of similar yielding support systemsin deep coal mining, particularly in the western United States. Application offundamental dynamic support principles to coal and coal measure rock, includingenergy absorption, stiffness and peak particle velocity of loading, is a primaryconcern. These principles must be applied to a number of dynamic failuremechanisms including coal outbursts, seismic shaking and pillar bumping. Theresulting insight provides a starting point for evaluating performance of existingcoal support elements under dynamic loading and the adaptability of yieldingsupport systems commonly employed in deep hard rock mining to deep westerncoal mining.

Coal & Energy: Environmental Health & Safety


Chair: T. Gray, Tetra Tech, Pittsburgh, PA

9:05 AM

A Creative Way to Obtain Leading Indicator Metrics from Routine

QHSE Work Practices

J. Stough; Syntex Management Systems, Inc., Houston, TX

This session will dive into the increasingly hot topic of “Leading Indicators” andhow combining a large global data set with some fundamental statistical methodscan result in both finding those factors which TRULY affect performance outcomesand the mathematical support to prove it. Initially, we will explore a rather largedata set involving thousands of sites and discuss how many different types of“potential leading indicators” are being extracted and analyzed to identify theTRUE mathematically-proven leading indicators of performance. We will review

the many different types of metrics ranging from the standard QHSE activities

such as ratio’s of near miss reports to high-severity incidents, percent ofemployees involved in proactive reporting activities, etc. to the much more “elusive”measurements like leadership, culture, responsiveness, etc… Finally, we’ll discusshow these variables can be analyzed to identify those factors which have thestrongest association to “outcomes” (losses) and briefly review how these “proven”leading indicators may be used on management scorecards to influence executionand continuously improve performance.

9:25 AM

Industry Input on the Design Manual Update for Coal Refuse

Disposal Facilities

R. Snow and C. Lewis; D’Appolonia, Monroeville, PA

In December 2007, an advance draft of the update to the 1975 Engineering andDesign Manual for Coal Refuse Disposal Facilities was provided for review andcomment by the coal industry. The update included advances made in the past 30years in dam safety and slurry impoundment design, construction, monitoring,inspection and instrumentation. Specific design sections added to the manualincluded engineering analysis for siting impoundments over or adjacentunderground mines and consideration of earthquake impacts on refuseimpoundment dam safety. Following a five month industry review period,comments were received from the industry representatives, university researchand teaching professionals, and federal and state agencies involved with damsafety and coal refuse disposal. The comments covered a broad spectrum oftopics, ranging from the application of the updated manual for regulatorycompliance to technical input on engineering methods and procedures. This paperwill describe the incorporation of industry input into the updated design manual.

9:45 AM

Water Quality Modeling and Optimum Restoration Planning of

Mining Impacted Streams

J. Ludwig, H. Zhang and S. Wilkes; Tetra Tech, Inc, Charleston, WV

Historic and current coal mining activities is one of the largest sources of metals(e.g., iron, aluminum, selenium, manganese) and acidity to streams of WestVirginia. Total Maximum Daily Loads (TMDLs) are being developed for numerousimpaired streams within the state as required by the Clean Water Act. The MiningData Analysis System (MDAS) was developed as a comprehensive datamanagement and modeling system that is capable of representing metal andacidity loads from nonpoint (e.g., abandoned mine land, AML) and point sources(e.g., permitted mine discharges) in the watershed and simulating instreamprocesses. The MDAS was configured and calibrated to model hydrology andwater quality for metal and pH impaired streams at watershed scale. Variousrestoration scenarios can be tested in the model to ensure the attainment ofcriteria throughout the watershed, achieve equity among categories of sources,and target pollutant reductions from the most problematic sources.

10:05 AM

Carbon Capture and Storage Overview –Technology

Development and Regulatory Uncertainty – What Does This Mean

for the U.S. Coal Industry?

J. Ekmann and R. Dolence; Leonardo Technologies, Inc.,Bannock, OH

Energy-related projects that emit (or offset) greenhouse gases (GHGs) areplagued with uncertainty. The uncertainty is especially critical to thosecontemplating the use of coal – the highest carbon to energy ratio of the threefossil fuels of coal, oil and natural gas. In 1970 the primary uncertainties werefuture electric demand, the cost of capital, and the return on investment grantedby a public utility commission; whereas in 2008, uncertainties include a global fuelmarket; resource depletion; future environmental policies, including traditionalpollutants, GHGs, and long term liabilities; escalating capital and labor costs;unproven technology options; and geopolitical upheavals arising beyond energy

and environment. Lawmakers are increasingly asked to ensure clean, reliable andfairly-priced energy supply and energy security. This paper will provide an overviewof carbon capture and sequestration (CCS) including a primer on CCS with anemphasis on geologic storage; technologies being developed to capture andfacilitate storage of carbon dioxide; statutory and regulatory development in theCCS arena; and lastly, CCS uncertainties related to coal utilization.



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Coal & Energy: Mine Fires


Chair: M. Trevits, NIOSH, Pittsburgh, PA

9:05 AM

Understanding Mine Fire Disasters by Determining the

Characteristics of Deep-Seated Fires

M. Trevits1, L. Yuan2, K. Teacoach3, M. Valoski4 and J. Urosek5;1NIOSH, Pittsburgh, PA; 2NIOSH, Pittsburgh, PA; 3NIOSH,

Pittsburgh, PA; 4MSHA, Pittsburgh, PA and 5MSHA, Pittsburgh, PA

The National Institute for Occupational Safety and Health (NIOSH) has beenconducting research addressing mine fire prevention, early and reliable firedetection, and fire suppression technologies. One portion of this program isfocused on the characteristics of mine fire combustion products and flame spreadthrough large scale deep-seated fire experiments and use of computational fluiddynamics (CFD) modeling. In this study, two large scale deep-seated fireexperiments were conducted; one fire consisted of only coal material (650 kg) andthe other utilized the two most abundant fuel sources found in a coal mine: coal(560 kg) and wooden cribbing blocks (125 kg). The fires burned to completionwhile the combustion products were collected and analyzed to determine themaximum rate of heat release. In addition, an array of thermocouples was placednear the surface and within the burning material to measure the flame spread rate.The results of the experiments were then used to develop a CFD model tosimulate the mine fires. This paper describes the deep-seated fire experiments,provides insight into the fire combustion products and presents the results of theCFD modeling work.

9:25 AM

Use of Pressure Swing Adsorption Technology for Inerting

Sealed Mine Areas with Nitrogen

M. Trevits1, M. Thibou2 and T. Mucho3; 1NIOSH, Pittsburgh, PA; 2OnSite Gas Systems, Newington, CT and 3Thomas P. Mucho &Associates, Inc., Washington, PA

As a means of providing a safe method to render sealed, abandoned mine areasinert, On Site Gas Systems built, under a NIOSH contract, an in-mine nitrogengeneration plant. The objective of this work was to create a reliable in-mine mobileplant that would extract nitrogen gas from the mine atmosphere and the generatedgas would be used to create and maintain a safe sealed mine area. The plant isbased on a novel design using pressure swing adsorption technology and is sizedto fit on a standard shield car for easy transport in and around an undergroundcoal mine. The plant is capable of producing about 300 scf/min of nitrogen gas.

After an exhaustive series of laboratory tests, the plant was field tested at theNIOSH Safety Research Coal Mine (SRCM) where a portion of the mine wassealed and rendered inert. During the test, the movement of the injected gas wasmonitored at several underground points to observe the progress and extent of theinerting process. This paper describes the plant design and the results of the fieldtest at the SRCM.

9:45 AM

In-Mine Study of High-Expansion Firefighting Foam

L. Chasko1, R. Conti5, R. Derick4, M. Krump3 and D. Lazzara2;1Disaster Prevention and Response Branch, NIOSH PittsburghResearch Lab, Pittsburgh, PA; 2Retired, NIOSH Pittsburgh ResearchLab, Pittsburgh, PA; 3Production, Twentymile Coal Company, OakCreek, CO; 4Retired, Twentymile Coal Company, Oak Creek, CO and5Deceased, NIOSH Pittsburgh Research Lab, Pittsburgh, PA

A mine fire is one of the most challenging safety issues facing a mine operator andcan occur at any location underground. Direct application of fire suppressionsystems must be quickly deployed and capable of extinguishing the fire beforeuncontrolled growth occurs. NIOSH and the Peabody’s Twentymile Coal Mineconducted in-mine experiments to determine the capability of high-expansion foamfor addressing underground fires. The tests were conducted in sloping entries withhigh capacity diesel engine powered foam generators. The following results wereobserved: a well-designed, maintained, and properly operated high-expansionfoam generator can propagate a foam plug hundreds of feet in steep upward-sloping multiple entries against ventilation pressure; stoppings and partitionsdesigned to contain a foam plug in upward-sloping entries must be substantiallyconstructed; and the predicted quality of foam concentrate can be significantlyless than the actual amount used due to foam losses, such as bubble breakageon dry surfaces. This paper describes the firefighting capabilities using high-expansion foam and describes the in-mine experimental tests and results.

10:05 AM

Dolph Abandoned Mine Fire Control Project

T. Gray1 and R. Bruhn2; 1Energy and Natural Resources, Tetra Tech,Pittsburgh, PA and 2Geotechnical, GAI Consultants, Homestead, PA

The Dolph Mine fire site is located in Lackawanna County, PA, approximately threemiles northeast of the city of Scranton. The fire is burning in both coal refuse (culm)and underground anthracite mine workings. It was reportedly begun by rubbishburning on top of the culm bank. The Offfice of Surface Mining retained GAIConsultants, Inc in 2006 to complete a site investigation to define the extent ofthe fire and to recommend fire control measures. A cut off trench was selected asthe principal control method. Plans and specifications were prepared in late 2006.The project was bid and a contractor selected in early 2007. The trench

construction was completed in 2007. This paper will focus on the investigation andselection of the fire control method.

10:25 AM

Effect of Longwall Face Advance on Spontaneous Heating in

Longwall Gob Area

L. Yuan and A. Smith; NIOSH Pittsburgh Research Laboratory,Pittsburgh, PA

To reduce fire hazards from spontaneous combustion in longwall gob areas, aseries of computational fluid dynamics (CFD) simulations were conducted byNIOSH to model the spontaneous heating of coal in longwall gob areas. Themodeling results demonstrate that spontaneous heating of coal usually occurredbehind the longwall shields and along the face with a bleeder ventilation system.Assuming the stationary longwall face, the spontaneous heating could turn to aspontaneous fire in several days for the most reactive coal under favorable

conditions. When the longwall face advances, the spontaneous heating processwill be affected. In this study, the effect of longwall face advance on thespontaneous heating in the gob area is investigated using the CFD modeldeveloped in previous studies. One longwall panel with a bleeder ventilationsystem is simulated. The width of the panel is 300 m, while the length of the panelis changed between 1000 to 2000 m. The spontaneous heating first develops inthe gob when the longwall face is stationary. Then, the face advances at a cer tainrate. The effect of the rate of face advance on the spontaneous heating processis examined.

10:45 AM

Evaluation of Smoke Detectors for Use in Underground Mines

C. Litton; Disaster Prevention and Response Branch, NationalInstitute for Occupational Safety and Health, Pittsburgh, PA

This paper details results from both laboratory experiments and an in-mineevaluation of two promising smoke detectors for early warning fire detection. Thetwo detectors were a prototype detector combining optical scatteringmeasurements with ionization chamber measurements and a commerciallyavailable photoelectric smoke detector designed for use in harsh environments. Inthe laboratory experiments, the responses of the two detectors were measuredwhen exposed to smoke particles from a variety of fire sources, including wood,coal, styrene butadiene rubber, and No. 2 diesel fuel. For the in-mine evaluation,the detectors were installed in an underground limestone mine and theirperformance measured over several months in order to assess their reliability andsensitivity to dusts and diesel exhaust particles. This report describes theexperiments and the details of the in-mine evaluation and proceeds to developguidelines and criteria for early-warning smoke sensors capable of the rapid andreliable detection of fires in underground mine atmospheres that may or may notbe contaminated by either dust or the products produced from diesel engines.

Coal & Energy: Surface Mining


Chair: S. Michalek, US DOL - MSHA, Pittsburgh, PA9:05 AM

Analysis and Control of Energy Consumption in Surface

Coal Mining

D. Bogunovic1, V. Kecojevic1, V. Lund2, M. Heger3 and P. Mongeon2;1The Pennsylvania State University, University Park, PA; 2Red HillsMine, North American Coal Corporation, Ackerman, MS and 3BNICoal, Ltd., Center, ND

The U.S. coal mining industry consumes a significant amount of energy, primarilydiesel fuel and electricity. As such, the continuous increases in energy prices andenvironmental control costs relating to CO2 emissions represent a substantialchallenge for the industry. This paper presents the results of research work on thedevelopment of an integrated data environment system for analysis and control of





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many private clients to develop interactive strategies for communications supporton public presentations for mining permit approvals, bond referendums, and onlineworkshops. GIS,Broadcast and web tools were produced to inform a varietyaudiences on the value of upgrading wastewater collection and treatment facilities,mining simulations to show end of project results, and seed testing procedures forlandscape architects. With the projects now underway results of each outreachcampaign can now be measured and feedback used to evolve the campaign asconditions change for construction, permiting and testing.

10:05 AM

Pipeline Assessment: Reducing Environmental Risk Using

Existing Technologies and Software

C. Miller; MWH Americas Inc, Tempe, AZ

Pipeline leaks and spills have resulted in loss of the precious process fluid andincreasing costs. To prioritize areas of pipeline that presented higher environmentalrisks GPS, GIS, PIPE2006 modeling software and MWH’s Engineering RiskAssessment (ERA)methodology was used. GPS was used to map the pipeline andrecord field data and the physical condition of various features of the piping.Environmentally sensitive areas that intersected any portion of the PLS pipelinewere also mapped. PIPE2006 model (flow pressure/analysis software) parameterswere input. To depict a more accurate condition, factors for pipe wall thickness,age, and exposure were input. The model identified sections that were over themaximum adjusted pressure rating of the pipe and posed a higher risk for failure.The final definition of pipeline segments consisted of categorizing the pipeline intosegments that fell into the same pressure category and traversed an area that hadsimilar environmental impacts if a release was to occur. MWH’s ERA methodologywas used to rank the various segments of pipeline with respect to their locationand their potential to cause environmental losses.

Environmental: Operating for Closure — Lessons Learned and Tools to Get Us There


Chairs: C. McKeon, Resolution Copper Mining, Superior, AZ

W. Tyler, Climax Molybdenum Company, Parshall, CO

9:05 AM

Redrocks Diversion Channel-Understanding and Improving

Channel Hydraulic Conditions

B. Gunn and L. Yenne; Mining, URS Corporation, Denver, CO, CO

The Redrock Diversion Channel is an existing diversion channel constructed in theearly 1970’s to divert runoff from the Redrock Canyon watershed. Since itsconstruction, the channel has been experiencing significant degradation and bankerosion. Headcutting has progressed upstream gradually from the downstreamend of the diversion channel. Continued channel degradation will potentiallyrelease tailing from Dams 2 and 3X, and impact existing reclamation activities. Ahydraulic and channel degradation analysis was completed to evaluate the existingchannel conditions. This indicated that the channel is experiencing extremely highflow velocities along an extended stretch of the channel for all sizable flowconditions. In order to minimize further degradation of the Redrock DiversionChannel grade-control structures are being constructed to stabilize the channel.The design includes construction of four check structures. This presentationpresents the details of the existing channel conditions, geomorphological analysis,alternatives analysis and details of planning, design and construction of therehabilitated channel.

9:20 AM

Unpermitting a Mine — or Demonstrating Successful Completion

of Reclamation Permit Requirements

A. Meglioli, A. Trippel, P. Corbetta and M. Taylor; ERM, GreenwoodVillage, CO

To un-permit a mine is not to end the company liability or obligation to managelong-term environmental liability but rather it is a process of taking credit forsuccessful completion of permit requirements. Since 1876, the Homestake Minehas produced over 40 million ounces of gold, and set a standard for the goldmining industry. Surface mining was completed in 1998 and underground miningin 2002. Homestake has recently fulfilled the reclamation requirements for most ofthe property that incorporates a financial assurance mechanism to supportsustainable post-closure activities. The verification of completion of requirementsand release of unused financial assurance obligations is a detailed independent,for agency and public credibility, summary of the entire written record of approvals,permits, and compliance orders. The review includes confirmation that allreclamation standards (performance or specific) were met for three distinct post-

mining land use categories. This independent verification process recognizesresponsible management and encourages commitment to fulfill remainingobligations and to establish a sustainable post closure period.

9:35 AM

Closing San Manuel Lessons from the World’s Largest Mine

Closure

D. Ortman; SRK Consulting, Tucson, AZ

In 2002 BHPBilliton announced closure of their San Manuel copper operationapproximately 40 miles north of Tucson, Arizona. Started by Magma Copper inthe early 1950’s, San Manuel disturbed approximately 9,000 acres and includedan underground mine that produced 700+ million tons of ore, an 1,100-foot deep

open pit, in-situ copper leach, heap leach & SX-EW, mill, concentrator, smelter,rail facilities, and 3,300 acres of tailings that stretch for five miles along the SanPedro River Riparian Area. BHPBilliton engaged SRK Consulting to provide sitecharacterization, engineering, permitting, and to assist with constructionoversight for the closure. These activities began in 2002 with closureconstruction starting in late 2004. The project was successfully concluded inJanuary of 2008 with completion of final construction and all permits in place.The work was completed ahead of schedule, under budget, with an exemplarysafety record, and without a single contractor claim. This presentation includesan overview of the closure at San Manuel and presents several of the keylessons to be learned from the project.

9:50 AM

Application of Best Available Technology to Reclamation Design

and Integration with Mine Planning

H. Hutson; BRS Engineering, Riverton, WY

BRS, Inc. has utilized Carlson’s Natural Regrade™ (NR)software to design thereclamation of abandoned mine spoils located in the Gas Hills Uranium District ofWyoming for the State of Wyoming’s Abandoned Mine Land Program. The projecthas been nominated for a National Association of Abandoned Mine LandPrograms award. The results of this project will be presented as a case history ofthe NR approach to surface mine reclamation. Based on the successful applicationof this new mine reclamation technology, reclamation designs for a plannedunderground uranium mine operation for Uranium One USA, Inc. will be presented.Critical elements will be the encapsulation of unsuitable materials, long termhydrologic stability, and handling of waste for final reclamation surfaceconstruction. The goal of the project will be to apply Best Available Technology(BAT) to reclamation design and fully integrate reclamation into mine planning.Benefits should include improved public and regulatory perception of the projectand facilitate permit approval. It is anticipated that the site will be reclaimed togeomorphic and vegetative conditions which will promote timely reclamation bondrelease.

10:05 AMWhat is “Integrated” Closure Planning?

J. Eshleman and A. Watson; MWH Americas Inc, Denver, CO

There are many examples of leading practices with respect to mine closureplanning, yet there is no consistent understanding of the requirements. We haveprogressed beyond the regrade and revegetate phase, through the incorporationof a range of environmental factors into planning. Now we must address thebroader environmental and social issues arising from our activities. In this sense,“integrated” refers to all stakeholders and refers to the various phases of themining cycle. We are cautioned to start with the end in mind. Previously wediscussed closure cost estimating that stressed the need to make allowance forexternalities often neglected early on. Our experience continues to show us thatwe avoid these issues at our peril, and integrated planning is a way to ensure thatour requirements are adequately described, that our scope for closure isappropriate, and that we are doing today what we can to limit out future liabilities.We provide an overview of the requirements for an integrated approach to closure

planning, cite examples from industry where this approach has proved beneficial,and propose a minimum standard for adoption by industry.





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optimized as early in the mine life as possible. Significant resources have beeninvested in the sub-surface hydro-geologic investigation to delineate thegroundwater regime. The hydrology of the area is a complex highlycompartmentalized system controlled structurally with normal and reverse faultingand a system of dikes and sills. An intensive monitoring system consisting ofmonitoring wells and multi-level piezometers have been installed to observeground water responses. Approximately six test wells have been pumped and theresponse monitored to determine long-term well yields, the horizontal and verticaleffects of pumping and hydro-geologic boundaries to flow.

Industrial Minerals: Reducing Carbon Footprint inIndustrial Minerals


Chair: R. Pruett, IMERYS, Sandersville, GA9:05 AM

The Carbon Footprint and Lifecycle Analysis of Kaolin and

Calcium Carbonate Used as Pigments for Paper

R. Pruett; IMERYS, Sandersville, GA

Paper and paperboard manufactures need to quantify the carbon footprint andenvironmental impact of their products to satisfy market, social, or governmentdemands. Coated paper products contain minerals such as kaolin and calciumcarbonate at significant levels, some coated paper grades have pigment mineralcontents as high as 45% by weight. Some uncoated paper can contain no mineralbut most uncoated paper contains some mineral to improve appearance, processefficiency, and cost. Super-calendared paper grades can contain levels of mineral

up to 35% by weight. The carbon footprint and environmental impact of kaolin andcalcium carbonate pigments can have a significant and favorable impact on paperand paperboard products. This paper reviews the methodology and impact ofpigments on the carbon footprint and environmental impact of paper andpaperboard.

9:25 AM

Carbon Impact on Your Operations

B. Nemeth; Sustainability & Environmental Services, USGCorporation, Chicago, IL

This presentation will disclose how to measure your true carbon impact of youroperations, and provide an action plan or strategy to managed that impact. Wewill discuss carbon impact, and what are your potential emission points (its morethen just the power you consume). Once this data is known, we need to explorewhether or not to certify the emissions, is there a value associated with theseemissions, and what should a facility manager do to manage and reduce theemissions in subsequent years. This presentation will provide a business casearound carbon emissions and provide the tools to determine a strategy to managecarbon in the future.

9:45 AM

Use of Waste Limestone fines for CO2 Mitigation: Opportunities

for the Crushed Stone and Cement Industries

W. Langer1, G. Rau2 and K. Caldeira2; 1US Geological Survey, Denver,CO and 2Lawrence Livermore National Laboratory, Livermore, CA

Large amounts of limestone fines coproduced during the processing of crushedlimestone may have application in the sequestration of carbon dioxide (CO2).Accelerated weathering of limestone (AWL) is proposed as a low-tech method tocapture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacture. AWL reactants are readily available,inexpensive, and environmentally benign. Waste CO2 is hydrated with seawater

to produce carbonic acid, which is reacted and neutralized with limestone fines insuspension, thus converting CO2 gas to dissolved calcium bicarbonate. AWLwaste products can be disposed of in the ocean where they may enhance growthof corals and other calcifying marine organisms that are threatened by increasesin ocean acidity. Access to an inexpensive source of limestone and seawater isessential, thus limiting AWL facilities within about 10 km of the coastline. Themajority of U.S. coastal power generation is within economical transport distance

of limestone resources. AWL presents opportunities for collaborative efforts amongthe crushed stone industry, electrical utilities, cement manufactures, and researchscientists.

10:05 AM

Delineation of Magnesium-Rich Ultramafic Rocks Available for

Mineral Carbon Sequestration in The United States

S. Krevor1, C. Graves1, A. McAfferty2 and B. Van Gosen2; 1Earth andEnvironmental Engineering, Columbia University, New York City, NYand 2U.S. Geological Survey, Denver, CO

The 2005 Intergovernmental Panel on Climate Change report on CCS suggested

that a major gap in mineral carbon sequestration is locating the magnesium-silicate bedrock available to sequester CO2. It is generally known that silicateminerals with high concentrations of magnesium are suitable for mineralcarbonation. However, no assessment has been made in the United States thatdetails their geographical distribution and extent. Researchers at ColumbiaUniversity and the U.S. Geological Survey have developed a digital geologicdatabase of ultramafic rocks in the continental United States. Data were compiledfrom varied-scale geologic maps of magnesium-silicate ultramafic rocks. Theserock types are potentially suitable as source material for mineral carbon-dioxidesequestration. The focus of the national-scale map is entirely on suitable ultramaficrock types, which typically consist primarily of olivine and serpentine minerals.Using this dataset with other datasets on nation-wide land use and literature oncarbon sequestration processes, one can develop estimates as to the capacityfor CO2 mineral sequestration within the United States.

10:25 AM

Enhancing the Reaction Kinetics of the Dissolution of Serpentine

for Mineral Carbon Sequestration

S. Krevor and K. Lackner; Earth and Environmental Engineering,Columbia University, New York City, CA

Mineral carbon dioxide sequestration is a greenhouse gas mitigation technologywhereby CO2 is disposed of by reacting it with magnesium silicate minerals toform a solid magnesium carbonate product. The technology offers virtuallyunlimited capacity to permanently store CO2 in an environmentally benign form.Energy consumption for initial processes developed, however, is high and it is notcurrently considered competitive with other sequestration technologies. Thecurrent low-cost process for mineral carbonation involves the carbonation of aslurry of magnesium silicate mineral. The process is limited by the slow reactionkinetics, and in particular the slow dissolution rates of the silicates in weakly acidicconditions. Enhancing the dissolution rate in weakly acidic conditions has beenidentified as one of the main opportunities for lowering the costs of this process.In this paper we discuss the results of dissolution experiments in which groundserpentine was reacted in weakly acidic aqueous systems containing organic andinorganic salt catalysts. Implications for the cost of an overall mineral sequestration

process are discussed.

10:45 AM

Geophysical Delineation of Magnesium-Rich Ultramafic Rocks

for Mineral Carbon Sequestration

A. McCafferty1, B. Van Gosen1, S. Krevor2 and C. Graves2; 1USGeological Survey, Denver, CO and 2Department of Earth andEnvironmental Engineering, Columbia University, New York, NY

Serpentinized ultramafic rocks are magnesium rich and are being evaluated aspotential source rock material for use in carbon-dioxide sequestration efforts.Serpentinized ultramafic rocks are also typically magnetite rich and hence canproduce distinct magnetic anomalies. We use newly compiled geologic data incombination with airborne magnetic surveys over parts of the Coast Range andSierra Nevada Foothills ultramafic belts in northern California to illustrate how themagnetic data can be used to extend the mapping of the ultramafic rocks into the

shallow subsurface and to identify potentially unmapped ultramafic rock. Thegeophysical data can provide three-dimensional information on the geometry,lateral extent, thickness, and volume of ultramafic rock that occurs in the shallowlyburied subsurface to minable depths. Results contribute to a first approximation ofaccessible rock material for mineral sequestration. Airborne magnetic surveysexist for the United States and, consequently, we believe this study demonstratesan adaptable approach that can be used to map the surface and shallowsubsurface extent of ultramafic rocks in other parts of the country.







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Mineral & Metallurgical Processing: Flotation Frontiers


ChairS: J. Carlson, Michigan Tech Univ, MI

R. Kappes, Newmont Mining Corporation, Englewood, CO

9:35 AM

Zeta Potential Studies Throughout a Hematite Processing Circuit

J. Carlson; Chemical Engineering, Michigan Tech, Houghton, MI

The purpose of this study was to determine how the zeta potential changedthroughout an iron ore processing circuit that utilizes flotation. Samples were takenbefore and after every chemical reagent addition and processing step. The resultsprovided in this paper reveal a snapshot of the zeta potentials at the iron oreprocessing circuit studied. Some of the results contradicted previously publishedliterature. For example, literature states the isoelectric point for hematite is at apH of 6.5, whereas our data shows I.E.P. values in the pH range of 3 to 5depending on the plant.

9:55 AM

Using JKMultiBal for Mass Balancing Flotation Circuits

S. Schwarz, S. Gay and D. Alexander; JKTech Pty Ltd, Brisbane, QLD,Australia

Benchmarking of flotation plant’s operating performance requires accuratemetallurgical sampling. Once the data has been collected, a mass balance isrequired to provide a consistent set of data from which plant performance can beassessed. Mass balancing is a key skill that many metallurgists and miningindustry professionals are aware of, but often put in the ‘too hard’ basket.Investigation of the mass balanced data enables better understanding of theflowrates within a system, as well as assessing the quality of data obtained fromsampling and surveys. There are various software programs available to assist inthe mass balancing and understanding of processing plants. JKMultiBal wasdeveloped by JKTech and is used to balance data in both one and two dimensions,i.e. balancing data on either sized or assay bases as well as size-by-assay. Withthe recent trend in flotation circuits becoming more complex, JKMultiBal has beenused to gain a better understanding of the processes occurring within the circuit.This paper provides a description of the program as well as several case studieswhere the two-dimensional mass balancing has resulted in improvements in plantperformance.

10:15 AM

Moly Plant Design Considerations

P. Amelunxen2 and R. Amelunxen1; 1Amelunxen Mineral ProcessingLtd, Brackendale, BC, Canada and 2Consultora Amelunxen MineralEngineering, Santiago, Chile

This paper presents the authors’ personal experiences in the design and operationof moly separation circuits in copper-moly concentrators. Topics discussed includecolumn cells versus mechanical cells; use of nitrogen; use of CO2 and sulfuricacid for pH modification; and general equipment selection, sizing andinstrumentation considerations. A benchmarking of main operating parameters forindustrial plants is presented. An upgrading curve for commercial column cleaningcircuits is also presented, showing that with average flotation kinetics and rougherconcentrate grades, technical grade concentrates can be easily achieved with fivecolumn cells operating in counter-current configuration.

10:35 AM

High-Confidence Flotation Testing at Xstrata Process Support

N. Lotter1 and D. Fragomeni2; 1Process Mineralogy, Xstrata ProcessSupport, Falconbridge, ON, Canada and 2Process Mineralogy, XstrataProcess Support, Falconbridge, ON, Canada

The reliability of a set of flotation results is key to minimizing project risk either atconcentrator commissioning, or at the point of implementing an improvement to anexisting concentrator operation. High-Confidence Flotation Testing was developedfor this purpose, and is part of the list of technologies of various scales used byXstrata Process Support (XPS) in addressing these projects. The methodology isbased on two principles: one, to ensure that the ore sample is representative andhas been well-blended and subsampled; two, to perform the flotation tests insufficient numbers of replicates with appropriate quality controls, so as to improvethe reproducibility of the test data. Across ten years of practice and continuousimprovement with this methodology at Xstrata Process Support, Sudbury, severalimprovements to this method have been developed. Some case studiesare reviewed.

10:55 AM

Implementation of Advance Control on Rougher Flotation at

Teckcominco Pogo Mine

X. Chen1, M. Sawada1 and J. McKay2; 1Mill, Teck Pogo Inc, Delta Jct,AK and 2Optimizing Control North America, Mesto Minerals Cisa,South Jordan, UT

The Pogo Mine, near Delta Junction, Alaska is a 2500 TPD gold operationemploying processes including grinding, gravity, rougher flotation, leach, CIP, andE/W. An OCS(Optimizing Control System) expert control system has beenimplemented on rougher flotation in early 2008. The OCS system communicateswith the Plant DCS(Distributed Control System) through OPC(OLE for Process

Control) communication. The initial strategy was to control the flotation cell frothlevel set points to achieve target froth velocities . This strategy was enhanced bycontrolling both level and air flow setpoints. The flotation cell air and level areadjusted to reach cell pulling rates (froth velocities). The pulling rate setpoints foreach cell are determined based on downstream capacity (concentrate surge tanklevel). The effect of pH and upstream disturbances is also taken into account inadjusting the air and level setpoints. Feed forward compensation is employeddown the flotation row to minimize disturbances.

Mineral & Metallurgical Processing: Student Poster Session


Chair: J. Kellar,South Dakota School of Mines and Technology,

Rapid City, SD

9:35 AM

Session Overview

The session will highlight mineral and metallurgical processing researchconducted by undergraduate and graduate students. The first part of the programwill feature oral presentations and the second portion will be a poster session bythe student researchers.

Somasundaran Symposium: Innovative ProcessingStrategies and Green Chemistry/Processes II


Chair: P. Taylor, Colorado School of Mines, Golden, CO

9:35 AM

Flotation of Fluorite in a Column Cell Operated as a

Conventional Cell

W. Aliaga, C. Sampaio, I. Brum and M. Batistella; Centro deTecnologia, UFRGS, Porto Alegre, Brazil

The aim of this work was the concentration of fluorite minerals in column flotationcells. These cells are normally operated adding a wash water flow from the top ofthe cell over a layer of froth which can reach up to two meter thick. To operatethem under steady state at these conditions, a sophisticated control circuit mustbe installed. However, such a circuit result expensive and is not generallyaffordable for low valued industrial mineral. In order to overcome such restrictions,column were tested to concentrate fluorite minerals under conditions similar tothose used for mechanical cells flotation. i.e. without wash water addition andunder a froth layer thickness naturally formed. Under these conditions, severalparameters were optimized such as collector concentrations, feed, concentrate,tail and gas flow rates. Excellent results were obtained in a pilot column whichsurpassed industrial results obtained in a bank of mechanical cells.

9:51 AM

Study on Process of Microbial Reduction of Vanadium

Matallurgical Waste Water

L. Haoran1 and W. Dianzuo2; 1Institute of process engineering,CAS,Beijing, China and 2Beijing General Research Institute of NonferrousMetals, Beijing, China

The process of Rhodoferax ferrireducens (R.f)) dissimilatory reduction ofvanadium matallurgical waste water is studied by the means of microbial fuel cell(MFC). Base on the domestication test of tolerance of R.f to NaVO3, The influenceof wastewater NaVO3 consistency, pH, and temperature on reduction V5+ withR.f are investigated. Optimum dosage of vanadium can promote the growth ofmicrobes, and there are same tendency and cycle between the growth of microbes



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and the reduction of V5+. In the early stages biological effect of the vanadiumcompound would increase the consumption of glucose, as glucose is oxidativedecomposition, the small molecule organic acids are also generated, which leadto lowering the pH level. H+ participate in the reaction of reduction V5+, and R.fdissimilatory reduction consume some small molecule organic acids, which makepH increase later. Key words: Vanadium Matallurgical waste water; microbialreduction; microbial fuel cell; microbial growth cycle.

10:07 AM

Treatment of Acid-Mine-Drainage (AMD) and Water Reuse in

Brazil by Flocculation-Lamellar Settling

J. Rubio and R. Silva; Mining Engineering, Universidade Federal doRio Grande do Sul, Porto Aregre, Brazil

The Acid-Mine-Drainage (AMD) generated in coal and sulfides ores is a seriousenvironmental concern in worldwide mining industry, due to the high levels of heavymetal ions, sulfate and acidity. This paper overviews the actual pollution problems inthe Brazilian coal mining, summarizes the main technological processes introducedrecently to treat fresh acid effluent waters and presents studies of acid watertreatment by flocculation followed by lamellar settling. AMD is characterized by a lowpH-value and high levels of sulfate and various metals ions, leading to pollution ofsurface and groundwater’s. This work describes studies (pilot scale 1-1.4 m3.h-1) totreat an acid effluent (pH 2.5-3.3) from an extinct mine (30-200 m3.h-1).Neutralization with lime at pH 9 and solids/liquid separation was conducted byflocculation-lamellar settling (FLS) to remove Fe, Al and Mn ions. Results at pH 9showed >90 % removal of metal ions and the total cost (energy and reagents) oftreatment varied between 0.3-0.4 US$.m-3, at loading capacities of about 5-6 m.h-1. It is believed that FLS has a great potential for the AMD treatment and water reuse.

10:23 AM

The Need for Different Reagent Management for Roughers,Cleaners and Scavengers in a PGM Operation – A Case Study

A. Anyimadu; Group R&D, Anglo American Platinum, Johannesburg,South Africa

Reagent optimization is an important activity for a large platinum operation for twomain reasons. Firstly the correct reagent regime and addition system can provideimprovement opportunities to flotation recovery and grade; and secondly, the costof reagents typically run into tens of millions of dollars per annum for a large PGMoperation, and therefore reagent optimization presents opportunity for costimprovement. This paper presents results of a case study, and discusses some ofthe practical considerations that must be taken into account in order to make gooduse of reagent improvements opportunities identified in research findings. Thisneed arises because, Rougher flotation, Scavenger flotation and Cleaner flotationunits require different reagent optimums, arising out of differences in parameterssuch as % solids, flotable gangue (as compared to flotable PGMs and sulphides),and particle size distribution of material being floated. The case studies are based

on material from a leading Platinum Group’s Merensky and UG2 Ores.

10:39 AM

Improving the Capture of Coarse Particles Using Bubble Clusters

S. Ata and G. Jameson; Centre for Multiphase Processes, Universityof Newcastle, Callaghan, NSW, Australia

Particles larger than 150 microns are generally poorly recovered by conventionalflotation cells. We have recently shown that the bubbles in an agitated flotation cellcould form clusters held together by bridge-forming hydrophobic particles. Wefound that the size of the clusters and the fraction of bubbles engaged in them,increased with increases in the particle hydrophobicity. Cluster formation maypotentially improve the flotation of coarse particles, because of the enhanced liftingcapacity of multiple-bubble- relative to single-bubble attachments. In the presentstudy, we have investigated the formation of bubble clusters and the effect of well-defined agitation on the their stability. Bubble clusters can be formed beneath acell containing a rotating impeller. The clusters then rise through a flow field ofknown turbulent characteristics. The size of the clusters at the time of formation iscompared with their conformation after they have passed through the turbulentzone, using a high speed camera. The influence of particle size and hydrophobicity,the bubble size and the shear rate, on the formation and breakup of the bubbleclusters, has been investigated.

10:55 AM

Dry Coal Beneficiation with a Vibrated Gas-fluidized Bed of

Magnetic Fly Ash

M. Fan1, Z. Luo2, D. Tao1, Y. Zhao2, Q. Chen2, X. Tao2 and Z. Chen2;1Mining Engineering, University of Kentucky, Lexington, KY and2School of Chemical Engineering and Technology, China University ofMining & Technology, Xuzhou, China

A novel dry coal separation method with a vibrated gas-fluidized bed of magneticfly ash is put forward for low rank coal beneficiation. The combustion of abundant

and widely reserved low-rank coals produces the high levels of air pollution. Thehazardous pollutants in low rank coals can not be efficiently removed byconventional wet coal separation processes because a considerable amount ofporose and easily friable low rank coals suffer serious particle size degradationproblems in water. The magnetic fly ash used in this study was derived from fly ashobtained as a byproduct of coal combustion. The vibration’s effect on the stabilityof a magnetic fly ash gas-fluidized bed was studied. The dry separation results of50.8-25.4, 25.4-12.7, 12.7-6.35 and -6.35 mm particle size coal showed that thevibrated gas-fluidized bed of magnetic fly ash can efficiently separate coals witha probable error E value less than 0.07t/m3.

11:11 AM

Microbially-Induced Separation of Arsenopyrite and

Bioremediation of ArsenicC. Naganna1 and N. Kootalai Ananthaiyer2; 1Biotechnology, M SRamaiah Institute of Technology, Bangalore, India and 2MaterialsEngineering, Indian Institute of Science, Bangalore, India

This paper discusses the role of acidiphilic microorganisms such asAcidithiobacillus on the beneficiation of arsenopyrite containing multisulfides(pyrite and chalcopyrite). Bacterial adaptation to arsenopyrite and controlledbacterial adhesion to mineral surfaces lead to selectivity in arsenopyriteseparation. Biotechnological strategies for remediation of arsenic are discussedfrom different angles such as (a) Bioremoval of arsenic in the jarosite precipitatesof Acidithiobacillus group of bacteria (b) Biooxidation of toxic arsenic As(III) tonontoxic As(V) (c) Microbial precipitation of dissolved arsenic through Sulfatereducing bacteria (SRB) and (d) Arsenic bioremoval using metabolic precipitatesof SRB. Development of innovative bioprocesses for environmentally benignmineral beneficiation processes is illustrated.

Wednesday, February 25 Afternoon

Coal & Energy: Deep Coal Geomechanic

2:00 PM • Wednesday, February 25

Chair: A. Iannacchione, University of Pittsburgh, Pittsburgh, PA

2:05 PM

A Back Analysis of the Crandall Canyon Mine Collapse

K. Heasley; Mining Engineering, West Virginia University,Morgantown, WV

The objective of this report is to back-analyze the August 6th, 2007 collapse at the

Crandall Canyon Mine in order to better understand the geometric and geo-mechanical factors which contributed to that collapse. In this work, the LaModelboundary-element program along with the best available information is used forthe back-analysis. To initiate the analysis, a six step base model of the mining inthe Main West area was developed along with an appropriate overburden grid.This base model included a step for each of the critical stages in the mining of thisarea. Next, calibrated values for the critical input parameters: rock mass stiffness,gob stiffness and coal strength, were developed. As a result of this back analysis,a number of conclusions can be made concerning the mine design and August 6thcollapse: 1) Overall, the area was primed for a massive pillar collapse because ofthe large area of equal size pillars, 2) The abutment stress from the active retreatsections and the adjacent longwall panels were significant contributors to thecollapse, 3) From the modeling alone, it is not clear exactly what triggered theAugust collapse.

2:25 PM

Critical Review of Stress Analysis Tools for Deep Coal Longwall

Panels Under Strong Strata

M. Larson and J. Whyatt; NIOSH, Spokane, WA

Proper employment of numerical stress analysis design tools relies on the abilityof a model to capture key elements of the geologic site model and simulate theirinteraction with a mine design. A deep longwall site model, representative of thegeology of the Wasatch Plateau and Book Cliffs coal fields of Utah, was used toevaluate boundary and volume element stress analysis tools. The site modelcontains a set of typical geologic features and observations of how these featuresrespond to mining. The analysis highlighted the considerable differences betweenboundary and volume element methods. Volume element tools can incorporateconsiderable detail and have fewer underlying assumptions, but this detail carr iesa considerable computational cost. Boundary element tools are much moreefficient. But this efficiency also comes at a cost of added assumptions. Theseassumptions were challenged by the presence of a strong sandstone unit in theoverburden, leading to boundary element results that depart significantly fromvolume element results. Insight into the nature and impacts of underlyingassumptions is essential to proper use of results from these tools in mine design.



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2:45 PM

Roof Support Issues and Possible Solutions on Coal Mines

S. Spearing and A. Mueller; Southern Illinois University,Carbondale, IL

The support of the roof in coal mines remains a critical safety issue with 3 fatalitiesfrom roof falls in 2007 and 430 injuries from roof falls in 2006. A snap-shot surveyby the authors of unplanned falls of ground in the industry revealed some usefuldata concerning fall dimensions, bolt lengths and spacings and the stand-up time.Using this data to calibrate a two dimensional finite element model, improvedsupport patterns have been developed.

3:05 PM

Analysis of Sudden Floor Heave in Deep Western US Mines

H. Maleki1, C. Stewart2 and J. Whyatt3; 1Maleki Technologies, Inc.,Spokane, WA; 2Bowie Resources, LLC, Paonia, CO and 3SpokaneResearch Lab, NIOSH, Spokane, WA

As mining continues toward deep reserves in thick western US coal fields, controlof mining induced-seismicity has become a priority in many operations in Utah,Colorado, and Wyoming. Gradual floor heave, common in many coal mines, hashistorically not been a safety issue. However, recent occurrences of sudden floorheave have occurred suddenly in concert with a seismic event. A review ofavailable data in three mines, including underground observations and backanalyses of an actual event, revealed the following contributing factors: (1) thickseam mined at depth exceeding 1000 ft, (2) geological discontinuities reducingthe in-situ strength of the coal with calculated factor of safety near 1 for the minefloor and ribs, (3) mining approaching areas of higher than normal stress gradient(Maleki and others, 1997) associated with previous mining, structural anomalies

or surface topographic highs, and (4) triggering energy from sudden failure suchas periodic caving established through pressure measurements in the gob (Maleki1981, 2008) or slip along geological discontinuities (although seismic data andunderground observations in one case excluded fault slip at mining horizon).

3:25 PM

Finite Element Assessment of the Influence of Caving on Barrier

Pillar Loads in Deep Coal Mines

W. Pariseau; Mining Engineering, University of Utah,Salt Lake City, UT

This paper quantifies the potentially beneficial effects of caving on barrier pillar loadsin deep, underground coal mines. Caving in deep coal mines changes pillar loadsand thus directly influences pillar stress, safety, and stability. Traditional equilibriumpillar load calculations such as the well-known tributary area method do not takecaving into account. In the new finite element approach, an elastic-brittle material lawlimits the range of purely elastic behavior by strata strength in well bench markedtwo- and three-dimensional FE codes (UTAH2/3). Loading beyond the elastic limitinduces complete loss of cohesion (tensile strength) while maintaining frictionalresistance (angle of internal friction) to stress in overburden strata. Although no site-specific data are used in the calculations, the stratigraphic column, elastic andstrength properties of major formations, and mine geometry are indicative of deepcoal mines in central Utah that use the longwall method of mining.

Coal & Energy: Underground Mining: Roof Control


Chair: J. Zelanko, MSHA Technical Support, Pittsburgh, PA

2:05 PM

Current Trends in Reducing Ground Fall Accidents in US

Coal MinesC. Mark and D. Pappas; Pittsburgh Research Lab, NIOSH,Pittsburgh, PA

Ground falls (roof and rib) have historically been responsible for about 50% of allfatalities underground but, in some recent years, this rate has approached zero.One important success has been a great reduction in the number of miners killedinby roof supports. The “Inby is Out” campaign and the later “Red Zone” effort, haveapparently borne fruit. Progress has also been made in pillar recovery. Safer miningtechnologies, including Mobile Roof Supports and cut sequences that leave a finalstump, have apparently contributed to a noticeable reduction in the number of fatalincidents. Analysis of recent incidents has underlined the need for carefulmanagement of the retreat mining process to ensure that miners keep out of harm’sway. While rock fall injury rates have been reduced, more than 400 miners continueto be injured each year by rock falling from between supports. Technologies suchas large roof plates seem to have helped somewhat, but experience has shown thatroof screen is by far the most effective defense against rock falls. Further advancesin this area will likely be the next big advance in ground control safety.

2:25 PM

Performance Characteristics for Roof Screen Used for Surface

Control in Underground Coal Mines

D. Dolinar; National Institute for Occupational Safety and Health,Pittsburgh, PA

The fall of small pieces of rock from between roof bolts causes over 80 pct of theground fall injuries in underground coal mines. Roof screen if installed on thebolting cycle can significantly reduce the number of these injuries. With roof screenas the surface of the roof fails, the screen will have to retain the broken rockwithout failing or excessive deformation. The load-deformation characteristics andthe load capacity of roof screen materials used for surface control in coal mineswere therefore evaluated in the laboratory in a specially built test frame. In the

frame, the screens were held in place by bolts and bearing plates at 4 cornerswhile a center load was applied to the screen. Both welded wire mesh andgeogrids were tested. Screen performance is determined by whether the screenis fixed or slips at the bearing plate. Parameters affecting screen performanceinclude the bearing plate conditions, bolt spacing, type of screen material, theamount of the screen covered by the plates, the size of the screen’s wires and thewire configuration. Screen design capacities were developed based on the screendisplacement, stiffness and failure or yield load.

2:45 PM

Evaluating the Moisture-Sensitivity of Coal Mine Roof Rocks

T. Klemetti and G. Molinda; Rock Safety Engineering Branch, NIOSH,Pittsburgh, PA

Moisture deterioration of clay-rich roof rocks causes high numbers of roof falls incoal mines in humid summer months. As a result, it is important to evaluate the

moisture-sensitivity of roof rock prior to mining. The National Institute forOccupational Safety and Health has evaluated three moisture-sensitivity indextests on roof rocks from 23 U.S. coal mines. The three tests were the University ofKentucky Weatherability Test, the Consol Energy Water Sensitivity Test, and theImmersion test. Of these three tests, the Weatherability and Water Sensitivity testsare more reliable in classifying the moisture-sensitivity of roof rocks. In addition tolaboratory testing, a monitoring site was set up at a mine in Ohio to evaluate thetime-dependent deterioration of moisture-sensitive roof rock. Rock fall collectionsshow that the moisture-sensitive shale is rapidly deteriorating. A roof sealantapplied to a portion of the test roof appears to be reducing the amount of rock fall.To date, the temperature and humidity monitoring has shown that the moisturelevels up bolt holes are not related to the humidity in the entries, rather they arerelated to moisture in the overlying strata.

3:05 PM

Improvements in Resin Cartridges for Coal Mining Rock Bolts

S. Spearing1, H. Pretorius2 and J. Oldsen3; 1Southern Illinois

University, Carbondale, IL; 2Industrial Synthetic Oils, Bothaville, SouthAfrica and 3Jenmar Corp, Pittsburgh, PA

Resin cartridges were introduced on US coal mines in the early 1970s. The useof resin cartridges has increased from around 40% of all installed bolts in 1988 toabout 70% in 2006 and it continues to grow, due to the effectiveness of the supportsystem. The main improvements for the end user since the introduction, have beenreducing the setting time thus dramatically improving bolt installation productivity,producing a convenient range of different cartridge diameters and lengths andreducing the cost whilst maintaining or even improving the installed performance.Little has however been done with the basic chemistry and the only improvementshave been associated with reducing the polyester resin percentage by addingmore inert fillers. This paper deals with the investigation and testing of a new resinchemistry that could hold significant benefits over the current system.

3:25 PM

Improving Roof Bolter Safety

A. Hammons1, D. Webb1, R. Damron1 and T. Burgess2; 1Lone MountainProcessing, Holmes Mill, KY and 2J. H. Fletcher & Co., Huntington, WV

Automated temporary roof support, (ATRS), systems have been incorporated intoroof bolters since the late 1970’s. Several different types and styles of ATRSsystems have been designed and deployed into the coal mining environment.During roof bolting many injuries have occurred from large pieces of draw rockfalling inby the ATRS beam and tipping back into the operators area. Other injurieshave occurred due to smaller, sharp rocks falling onto the operators hand and armduring initiation of roof bolt drilling. These injuries are attributed to weak immediateroof, sometimes called roof skin failure. Design innovations such as the ATRSmounted outby rocker pad deflector system have been designed to improve theroof bolter operator safety. This paper will inform the reader of the hazards,machine evolution through different design solutions, and the current state of theart in preventing roof skin failure injuries when roof bolting.



87

Environmental: Advances and Updates in Remediationand Closure


Chairs: F. Jordan, Golder Associates Inc., Albuquerque, NM

T. Nakaoka, Resolution Copper Mining, LLC, Superior, AZ

2:00 PM

Execution of Mine Closure at Goldcorp Inc.’s San Martin Mine in

Honduras

R. Chaves; Minerales Entre Mares de Honduras, Tegucigalpa,Honduras

The San Martin Mine is a gold heap leaching operation located approximately 70kilometers from the Honduran capital of Tegucigalpa. Mining operationscommenced in 2000 and were completed late in 2007, while heap leachingoperations continue. Reclamation was executed concurrently with operations tothe extent practical. The area has distinct rainy and dry seasons and closureobjectives include: prevention and mitigation of acid rock drainage, sediment anderosion control, and mitigation of visual impacts. Final closure is well underway atSan Martin and this paper is to describe the closure processes conducted to date,problems encountered, and the subsequent lessons learned.

2:20 PM

Management of Intense Precipitation Events, San Antonio

Tailings Facility Closure Project, Mexico

F. Torrecillas; Minera San Dimas, Municipio de San Dimas, Mexico

The San Dimas Mining District is located in the Sierra Madre mountain rangeapproximately 125 km from the Pacific coast in Northwestern Mexico. The ruggedmountainous terrain and steep walled canyons in the San Dimas district havepresented formidable challenges to tailings management. In 1993 the constructionof the most daring and challenging tailings embankment of the San Dimas Districttook place at the San Antonio mine; where a meander within a narrow river bedwas chosen as the location of the main tailings deposit. In addition to the factor ofsafety, one of the key performance drivers of the closure design is themanagement of intense precipitation events. Short violent tropical storms from thePacific can cause maximum flow rates up to 600 cubic meters per second in aperiod of 24 hours. Precipitation from a storm event with return period of 1,000years could flood the upstream face and over top the dam. This paper describesthe actions that are taking place to guarantee that the San Antonio Tailings Damcontinues to stand throughout the passage of time.

2:40 PM

Remediation and Expansion of the Cupias Tailings Dam, San

Dimas District, Mexico

S. Alvarado; Minera San Dimas, Municipio de San Dimas, Mexico

The San Dimas Mining District, owned by Goldcorp Mexico, is located in the stateof Durango, on the border of Sinaloa state, Mexico, within the Sierra Madremountain range. Silver and gold ore from numerous underground mines in thedistrict is hauled to a central beneficiation plant. Following the extraction process,the tailings are discharged to the Cupias tailings dam, which has been in operationsince 1985. During 2002, the dam’s safety factor was found to be lower thanInternational Dam Safety guidelines. This led to the construction of stabilizationberms to achieve the required safety factor. As few suitable tailings facility locationsare available in the steep canyons surrounding the plant, a number of expansionworks to increase the dam’s capacity were also undertaken to obtain an additional16 years (at 2600 tonnes per day) of dam life. This included the conversion of thetailings process to filtered tailings and the use of compacted filtered tailings in the

berm construction.

3:00 PM

Site-wide water balances 101: Identifying Requirements and How

to Begin

P. Williamson1, A. Johnson2 and L. George1; 1Water ManagementConsultants, Denver, CO and 2HydroGeoLogica, Golden, CO

Site-wide water balances (WBs) are critical tools for the design, day-to-day watermanagement, and closure of mines, particularly for large scale, open pit operations.In addition, a predictive site-wide WB is one of the requirements for the InternationalCyanide Code certification. In most cases, the challenge is not the design andimplementation of the WB, but identification of the specific objectives of the WBand collection of the necessary data. Development of a WB should start with aclear definition of the type of WB required, an understanding of how it will be usedby the mine, and identification of the information required to meet the objective. Itis vital to develop a focused and robust data collection and management system

to provide input/verification of the WB, based on a clear understanding of waterflow components. Where long term WB maintenance is required, the datamanagement process should include evaluation of existing and proposed datastreams, and development of data collection and management protocols. The mostappropriate of the available software platforms should be selected based on theanticipated use and complexity of the WB, ease of use, and cost.

3:20 PM

Remediation of Historical Smelter Contamination Midvale Slag

Superfund Site – Operable Unit One

D. Wilson; ERM, Rio de Janeiro, Brazil

The Midvale Slag Superfund Site was affected by emissions of arsenic and leadfrom historical smelting operations. A private developer, Mercer Bingham Junction,LLC. (MBJ), purchased 130 acres of the Superfund site for the purpose ofperforming appropriate environmental remediation, and developing mixedresidential and commercial real estate. Development of the property wasconducted in cooperation with U.S. EPA Region 8 (EPA), the Utah DEQ andMidvale City. The project demonstrates a cooperative approach through whichlands affected by historical mining and smelting operations can be restored forbeneficial, alternative uses. A Soil Management Plan (SMP) was prepared toaddress the methodologies for identifying, removing and managing the metalsaffected soils, plus landfill debris and slag materials. The soil excavation andmanagement activities were conducted during 2006 to meet EPA requirements.Upon completion of the work, a Soil Management Report was submitted andapproved by the agencies documenting that the land is now suitable forunrestricted reuse for the residential and open space parcels, and no further soilexcavation or removal is required for land development.

3:40 PM

Inactive McCracken Mine Closure Project

D. Abranovic1 and J. Deisley2; 1ERM, Scottsdale, AZ and 2TeckCominco, Vancouver, BC, Canada

An inactive turn of the century silver mine was determined to pose a potentialpublic safety risk due to the presence of numerous unsecured mine workings. Aphased approach for developing a final closure design was implemented such thatall relevant site information and stakeholder concerns were considered Thisproject included the implementation of interim safety measures that quicklyreduced the safety risks associated with the site. Developed mine closureprocedures and requirements necessary to prevent human access to the minefeatures and ensure the preservation of critical habitat; historic and/or culturalassets; and water quality. The project includes closure of 47 features by backfilling,installation of a polyurethane foam plug, and the installation of nine bat compatibleclosures. Closures were designed to prevent access into the mine openings andensure compliance with state and federal laws. The project was recognized by theState Mine Inspector as an example of how a private-public partnership can

facilitate lead to the successful execution of a closure project..

4:00 PM

Tools for Estimating Environmental Risk Applicable for Mining

Closure and Other Management Activities

A. Redman1, J. McGrath2, R. Santore4 and D. Di Toro3; 1HydroQual,Logan, UT; 2HydroQual, Mahwah, NJ; 3University of Delaware,Newark, DE and 4HydroQual, East Syracuse, NY

An important aspect of mining procedures is the assessment of the environmentalrisk during closure evaluations or other management activities. Evaluating theecological risk of hard rock mining is difficult due to the complex chemistry drivingthe release and bioavailability of metals and other agents to the environment. TheBiotic Ligand Model (BLM) has been developed in partnership with regulatoryagencies and industrial associations to address bioavailability of metals to aquaticorganisms. The BLM provides a framework for establishing scientifically defensiblecriteria for metals regulations on a site-specific basis, which is useful for miningsites in locations where environmental regulations have not been extensivelydeveloped. The BLM has been extended to soil and sediment as well as a versionfor estimating bioavailability of cyanide. The BLM can be linked with watershed-scale fate and transport models, speciation models and waste-rock weatheringmodels. Similar models and frameworks have been developed for petroleumproducts (e.g., PETROTOX) that may have application in estimating environmentalrisk of fuel oil spills or oil shale development projects.

4:20 PM

Hydrological Flow Through Rock Piles

M. Fredlund; SoilVision Systems Ltd., Saskatoon, SK, Canada

The quantification of the flow through a waste rock pile presents an interestingchallenge. The flow aspect of the water phase in a rock pile represents an importantaspect of the long-term performance of a rock pile. The water phase has impact onthe geochemical reactions which take place and therefore influences the production







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databases, and applications software. In this environment it is important to stayfocused on the longer-term nature of information, along with key attributes suchas spatial context. Data should be managed not only to meet the immediaterequirements, but with an eye to what might be useful in future analysis andvisualization tools. These tools while impossible to predict with any accuracy arelikely to include unlimited storage and computing resources providingopportunities to create massively integrated models to drive discoveries.

3:25 PM

Safe, Easy and Efficient Geological Mapping using 3D Laser

Imaging and Digital Photography

J. Dolan; Maptek I-Site, Lakewood, CO

With the current high level of activity in our industry comes a shortage of availablemining professionals. This includes Geologists who, among other duties, areresponsible for producing geological maps for analysis. This shortage of personnelhas two effects on geological mapping. First, some areas of interest are notmapped. Secondly, only some of the major geological features are mapped dueto time constraints put onto the Geologists. Additionally, areas that requiregeological mapping are not often mapped due to hazardous conditions such asrock falls, potential failures and ground support issues. The application of 3D laserscanning technology has been used for years to create topographical maps in themining industry. The combination of this technology and digital photography nowyields a tool that safely, easily and efficiently can be used to create high resolution3D images suitable for geological mapping. From a safe distance, 3D laserimaging can acquire the data necessary to render the digital photograph over apoint cloud allowing mapping of the entire area and all its geological features.

Industrial Minerals: Emerging Issues for IndustrialMinerals in the Western States


Chair: W. Langer, US Geological Survey, Denver, CO

2:05 PM

Bentonite Commodity Markets from 1992 and Future Trends

W. Miles; Miles Industrial Mineral Research, Denver, CO

The major USA commodity markets and value for bentonite have increased since1992. Bentonite has many uses that are tied to the USA economy and other usesthat are tied to the USA population. Pet waste absorbent, a new use for bentonitebeginning in 1989, is now the largest market. As the need for oil and gas increasesin the USA and the world, bentonite for drilling fluids is also growing and maybecome the largest market in the near future. Other commodity markets increasedor decreased as changes occurred in each application. Major commodity marketsinclude: absorbents, adhesives, animal feed additives, ceramics, drilling fluids,fillers & extenders, pond sealing, pelletizing, refractories, and water proofing.Exports of bentonite change significantly each year. Future trends are expectedto rise and fall by market with the USA economy.

2:25 PM

The Geologic Relationships of Industrial Mineral Deposits and

Asbestos in the Western United States

B. Van Gosen; U.S. Geological Survey, Denver, CO

In recent years, U.S. regulatory agencies have placed a greater emphasis onidentifying and regulating asbestos dust exposures in the mining environment,with a particular focus upon industrial mineral deposits in which asbestos occursas an accessory mineral. Because asbestos minerals form in specific geologicenvironments, only certain predicable types of industrial mineral deposits canpotentially host asbestos mineralization. By applying a basic knowledge ofasbestos geology, the costly and time consuming efforts of asbestos monitoringand analyses can be directed towards those mineral deposit types most likely to

contain asbestos mineralogy, while saving efforts on the mineral deposits that areunlikely. While the vast majority of industrial mineral deposits in the Western UnitedStates are asbestos-free, there are several types that can, in some instances,host asbestos mineralization (or be closely associated with it). These industrialmineral deposits include a few types of aggregate, dimension, and decorativestone, and some deposits of chromite-nickel, magnesite, nepheline syenite,olivine, rare earth elements, talc, vermiculite, and wollastonite.

2:45 PM

Factors Influencing Use of Mineral Admixtures for Past Decade

in the Western U.S

G. Hoffman; NM Bureau of Geology, NM Inst. of Mining and

Technology, Socorro, NMSustainable development has brought social, environmental and energy efficiencyconcerns together with management and governance of natural resources. Cementmanufacturing, an energy- and natural resource-intensive industry, is adapting tomeet sustainable development goals. Emission standards for cement plants andincreasing energy costs have lead to changes in the use of natural resources andrecycled materials. Utilizing pozzolans or supplementary cementitious materials(SCMs) as mineral admixtures in blended cement, or as a substitute for cement inconcrete, lowers energy costs and CO2 emissions. Although the western U.S. isrich in natural pozzolans, artificial products, particularly fly ash, have greater usageas mineral admixtures. Pozzolans and SCMs have many beneficial properties, suchas preventing alkali-silica reactivity, a common problem in the western U.S. Barriersexist for mineral admixtures in the cement and concrete industries because of pastinconsistencies in quality or availability. New environmental regulations on theindustries producing artificial mineral admixtures could adversely affect the qualityand quantity of these materials in the future.

3:05 PM

Montana Sapphires - Past, Present, and Future

R. Berg; Montana Bureau of Mines and Geology, Butte, MT

Montana sapphires were first discovered in the Helena area in 1865 andsubsequently were discovered in other alluvial deposits in southwestern Montanaand also in a lamprophyre dike at Yogo in central Montana. From about 1900 untilthe 1930’s, when synthetic sapphire came into use, mines produced sapphireslargely for watch bearings with lesser production for the gemstone market. TheYogo deposit is now mined on a limited basis for the gemstone market and two ofthe alluvial deposits are mined to produce material for fee-sieving of sapphire-bearing gravel and for direct sale of gemstones. The generally pale-coloredsapphires from the alluvial deposits in southwestern Montana are heated toenhance their colors whereas the blue sapphires from the Yogo deposit require notreatment. Markets for sapphires from both the alluvial deposits and the Yogodeposit are strong. In spite of a reported historic production in excess of 45 tonnes,mineable resources appear to remain at most of the major deposits. Also an

abundance of untested lamprophyre dikes in central Montana may host bluesapphires similar to those at the Yogo deposit.

3:25 PM

Determining Vermiculite Source and Amphibole Content with IR

Spectroscopy and Electron Probe Microanalysis

G. Swayze1, H. Lowers2, R. Driscoll3 and R. Clark4; 1U.S. GeologicalSurvey, Denver, CO; 2U.S. Geological Survey, Denver, CO; 3U.S.Geological Survey, Denver, CO and 4U.S. Geological Survey,Denver, CO

Some sources of vermiculite ore contain trace to minor amounts of asbestiformamphiboles, which are known to cause asbestosis, lung cancer, andmesothelioma. Evaluation of this potential hazard traditionally involves collectinga vermiculite sample from an attic or wall for time-consuming analyses at an off-site laboratory. The goal of this study was to determine if near-infrared reflectance

spectra could be used to identify the source of the vermiculite ore. Spectra of 27expanded vermiculite samples, including attic insulation, commercial packingmaterials, and horticultural products, were measured with a portable fieldspectrometer. The sources of the vermiculite samples were distinguished basedon differences in elemental composition as measured by electron probemicroanalysis. Reflectance spectra of the samples have absorptions that vary inwavelength position and relative intensity depending on composition, which allowsdetermination of source and detection of potential amphibole/talc contamination.

3:45 PM

Production of Iodine from Morrowan Sandstones in the Anadarko

Basin of Northwestern Oklahoma

S. Krukowski; Oklahoma Geological Survey, Norman, OK

Iodine-rich brines in the Anadarko Basin of northwest Oklahoma are the solesource of iodine production in the U.S. Amoco Production Company discoveredthe iodine brines near Woodward, Oklahoma. The brines were sampled and

Photo from Denver Metro Convention & Visitors Bureau





Documents

Annual Meeting 2009 Technical Program