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By A. D. Davis, C. J. Webb, C. S. Johnson, J. L. Porter

The abandoned Belle Eldridge Mine near Deadwood, South Dakota, is on land controlled by the U.S. Bureau of Land Management (BLM) property. The mine produced primarily lead and zinc during the first half of the twentieth century. The BLM has expressed concern about acidic drainage as well as elevated arsenic levels in tailings and waste rock at the site. The mine site was evaluated for remediation in 1998 and 1999. Recent reclamation and remediation work included substantial regrading of waste rock, removal of material where metal loading were of concern, and re-routing of drainage from an adit. Trenching at the site shoed a greater volume than originally calculated during site characterization. Material was removed to a repository that was constructed at a nearby drainage divide. Because of physical hazards, the BLM has decided to remove some historic structures. However, a search of mine records and an inventory of archival materials were complete to preserve the history of the site.

Jan 1, 2002

By Joel Moskowitz

In 1990, the United States General Services Administration (GSA) issued a contract for design and construction of a new federal court building in New York City. Mueser Rutledge Consulting Engineers (MRCE) served as Project Geotechnical Engineers. The project site is in the historic government district at Foley Square. It is surrounded by the New York County Courthouse to the west, an existing federal prison building and federal courthouse across Pearl Street to the south and southwest, an office structure to the north, and a residential tower to the east. The interior of the site was crossed by streets which have now been demapped. As with many urban sites, this site was previously occupied by tenement buildings or industrial structures demolished near the turn of the century. Remains of old building foundations were exposed during construction excavation. In addition, buried fuel oil tanks servicing the adjacent courthouse were removed and the usual assortment of urban utilities had to be relocated for the new building foundations. Ground surface elevations vary from about 4.5 to 6 m above the local Mean High Water Datum Plane.

Jan 1, 1996

For the use of those who prefer manila rope to wire rope for light hoisting and hauling, the Ingersoll-Rand Co. has brought out a new model Little Tugger Hoist which is designated No. 11. The square piston, reversible driving engine, automatic lubrication, inclosed gearing, rum release clutch and worm-operated band brake are essentially the same as in the No. 1 model which was introduced about two Years ago. The main differences are in the diameter and length of the drum, the width of the flanges and, necessarily, the main frame and overall dimensions. The new No. 11 Little Tugger has a hoisting drum 7 in. in diameter by 17 in. long with 5-in. flanges. This accommodates 300 ft. of 7/8 -in. manila, rope. The maximum capacity of this hoist is conservatively rated at 600 1b. The weight of the hoist itself is 358 lb. It is 21 ½ in. long, 31 ¼ in. wide and 23 in. high.

Jan 12, 1916

By R. Filippone, Donald Leroux, Colin Hardie, G. Leichtle, Cesar Gomez, Jim A. Finch

"Bubble surface area flux (Sb) is the surface area of bubbles per unit time per unit cross-sectional area of flotation machine. The units are: (m2 bubble surface/s)/(m2 cell) or s -1. For bubbles of mean size db (m), s b = 6-Qg/A db where Qg is the gas rate (m3/s), and A the cell cross-section (m'). This parameter is now receiving wide attention as the possible key machine variable in flotation diagnosis and modelling. The concept is described and the potential use of sb is illustrated by work on flotation columns and mechanical cells. In column flotation of recycled paper, the dependence of ink recovery on s b was the same regardless of size of column or type of sparger. In mechanical cells, it has been established that the rate constant is related to Sb independent of impeller type.The use of s b is limited by the problem of measurement, primarily that of estimating db. A prototype probe designed to estimate db (and hence sb) based on conductivity measurements is described. Exploratory work with the probe in a mechanical cell suggests the promise of making estimation of s b routine.INTRODUCTIONFlotation is the result of interaction among variables associated with the feed particles, chemistry and the machine (flotation cell). Trying to isolate the effects of each aids in process diagnosis and is at the centre of attempts to model flotation. The machine variables that have been investigated include the air flow number, the power number and specific power (Harris, 1976). None have survived as the basis for predicting flotation response perhaps because they did not include directly the properties of the bubble swarm (or dispersion). Recently, Gorain (1 997) explored the relationship between the flotation rate constant and various ""gas dispersion"" parameters notably: superficial air rate (Jg = Qg/A, where Qg is the volumetric gas rate and A is cross-sectional area of cell), bubble size (db), gas holdup (Eg, i.e., the volumetric fraction of a cell occupied by gas) and bubble surface area flux (sb = 6.Jg/db). Of them all, Gorain et al. (1997) conclude that the latter, the surface area flux, correlated best with the flotation rate constant. This concept was adopted from column flotation where it was used to estimate, among other factors, the maximum amount of gas that could be injected (Finch and Dobby), 1990). Let's start by reviewing the concept. Following that some examples of where the concept has been applied will be described to illustrate the current interest and finally we will consider how to measure the surface area flux."

Jan 1, 1999

By B Brown, P J. Hommert, B J. Thorne

"Early attempts at estimation of stress wave damage in blasting by use of finite element analysis met with limited success due to numerical instabilities that prevented calculations from being carried to late times. A"" improved damage model based on microcrack growth in tension allows finite elementcalculations which remain stable at late times. Estimation of crater profiles for blasting experiments in granite demonstrate successful simulations with this model."

Jan 1, 1990

By Donald J. Murphy

Longevity of structural units, as compared to the planned useful life of a facility, always is a design consideration. Typical concerns include slow decay due to environmental factors, and changes in constitutive relationships governing the performance of the material involved. With respect to foundations, the usual items of interest are corrosion of steel and concrete, and time dependent behavior of the soil/structure system. For piles, as with other foundations, deterioration is precluded, mitigated or otherwise accounted for by assessing properly the ambient situation (sulphates, pH, stray currents, resistivity) and providing safeguards, such as resistant construction products, oversizing, coatings, and/or cathodic protection. On the other hand, long term performance of the pile foundations, as affected by time dependent characteristics of the supporting soil or rock, can be predicted and controlled only with a synergetic coupling of analyses and field tests. The history of a project for which this approach was followed forms the basis for this paper.

Jan 1, 1986

By P. Huang, D. W. Fuerstenau

Various factors that control the natural flotability of talc, including differences due to crystal face and edge effects, were delineated. For study of talc depression phenomena, dextrin was used as a model depressant. For the enhancement of talc flotation, dodecylammonium acetate (DDAA) was used as the collector. The interaction of DDAA with talc was assessed by flotation experiments and electrokinetic (zeta potential) measurements, from which the role of hydrophobic bonding can be demonstrated. The results presented in this paper provide useful information on how the crystal chemistry and surface chemistry control the electrical double layer, adsorption phenomena, wettability, and flotation behavior of talc in aqueous media.

Jan 1, 2003

By T. H. Eyde

Estimated natural zeolite production worldwide during 2004 remained at about 3.6 Mt (4 million st), about the same as in 2003. China continues to be the largest producer of natural zeolites followed by Cuba, Germany, Japan and South Korea. This may be changing, however. Since 1988, zeolite production from Australia, Indonesia, Malaysia, New Zealand, Philippines and Thailand has increased rapidly. Most of the production is consumed in aqua culture. Global demand for seafood has exceeded the ability of the oceans to supply it without over fishing. Zeolite minerals remove ammonia compounds from the ponds in which fish and shrimp are grown. It is estimated that, in Thailand and Indonesia more than 55,000 farms produce260 kt (286,500 st) of shrimp. Therefore, as shrimp production increases, so does zeolite consumption.

Jan 1, 2005

The Mungana group of mines, in the Chillagoe district, yielded 334,000 tons of ore giving 31,831 tons of lead, 7,907 tons of copper and 3,228,600 ounces of silver. The Girofla mine produced approximately 220,000 tons of ore, and with the Lady J ane mine supplied most of the ore from this centre. The deposit was discovered in 1888, but active development did not commence from the main shaft until 1898. A subsidiary of the New Chillagoe Railway and Mining Co. Ltd., the Mungana (Chillagoe) Mining Co. Ltd., worked the mine from 1902 until 1914, selling copper, copper-lead, lead ores and fluxes to the smelters at Chillagoe. The smelters stopped operations in 1914 when the richer ores of the Girofla had been worked out and production from the Lady Jane had ceased due to heavyground and fire. The Girofla shaft was 823ft. deep with a cross-cut at 810ft. At the 710ft. level contour drives had delineated the orebody, which had been stoped about 10ft. above the level. Except for flux ores which had been stoped only for favourable smelter tariffs, the orebody was practically exhausted above the 610ft. leveL Under company ownership the mine yielded 139,265 tons of an average grade of 4.QlYr copper, 16.2% lead and 12.5 oz. per ton silver.In 1921 the Queensland Government re-opened the mine and worked it until 1927. The North Lode (Fig. 2) was discovered almost immediately at the 100ft. level and was worked down to the 410ft. leveL The ore from this branch and the completion of the stope at the 710ft. level yielded about 80,000 tons of ore averaging 0.4 copper, 9.8 lead and 7.8 oz. per ton silver during this period.

Jan 1, 1953

Jan 1, 1963

By W. P. Nel

The introduction of the Higher Education Qualifications Framework (HEQF) and the updated Higher Education Qualifications Sub-Framework (HEQSF) has caused many South African university departments to rethink their programme qualification mixes (PQMs). In addition to the requirements stated in the HEQSF, a number of other factors have to be taken into consideration by a university department. These factors include, for example, the standards generated by the Engineering Standards Generating Body (ESGB) and subsequently approved by the Engineering Council of SA (ECSA) and the need to prepare students for various categories of professional registration with ECSA. This means that a university department has to choose the correct mix of Learning Programmes (LPs) from the HEQSF menu (which consists of 13 types of LPs). Preparing students for ECSA registration is aligned with the mission of universities, which is to teach and undertake research. However, research and the LPs associated with research go beyond the requirements for current ECSA registration. Assuming that universities offering engineering LPs would elect to prepare students for both ECSA registration and teach them to produce research outputs, which is mostly done at Master and Doctorate levels (NQF Levels 9 and 10), then it follows that academics are more interested in NQF Level 5 to 10 pathways (abbreviated as ?L5-10?) rather than the shorter pathways required towards professional registration. (For example, ECSA requires an NQF L5-L7 pathway for registration as a candidate professional technologist. This specific pathway may consist, for example, of two LPs, namely the 360-credit Diploma and the Advanced Diploma.) A L5-L10 pathway is a combination of LPs that will prepare the learner with a NSC (or equivalent qualification at level 4) to Doctoral level (level 10). Universities may choose at least four major pathways from the HEQSF menu in order to educate and develop students from NQF Level 5 to 10. However, various pathways towards registration in the category of candidate with ECSA are also embedded into these four NQF L5-L10 pathways, where each consist of a unique combination of LPs. Each of these pathways has an opportunity cost, and economic reality means that smaller departments may have to choose between the four pathways. Of all the many factors involved in PQM decision-making, the focus of this paper is on the HEQSF requirements, ECSA standards, and ECSA registration and how these, together with the various qualifications and educational LPs provided for by the HEQSF may impact on the PQM decision taken by engineering departments and schools at South African universities. The proposed four NQF L5-L10 ?pathway tool? for PQM decision-making may be useful for pointing out the advantages, disadvantages, and applications of the various pathways and combinations of pathways. Rather than deciding from a menu of thirteen qualifications and associated LPs, this article proposes that decision-making be undertaken on the basis of a menu of four main articulated ?NQF L5-L10? pathways (which also include one or more of the ECSA?s pathways for professional registration). The proposed ?NQF L5-L10 pathway? tool is an attempt to move one step closer to the aim of achieving a structured decision-making approach for designing a PQM at departmental level.

Jan 1, 2014

By J. D. Patsey, G. T. Lineberry

Introduction A computer program was developed for analyzing drum-type hoists before modifying an existing system or designing a new one. Its use permits the preliminary evaluation of a system before seeking technical assistance from mine hoist designers and manufacturers. The user-friendly program accepts a variety of data and analyzes hoisting systems for any balance state. The program can be used to calculate skip capacity to yield a desired production rate, solve for drum face width, select a permissible wire rope, estimate total horsepower of the hoist plant, and estimate annual power cost. Whether required for a large mining complex or for a relatively small operation, a hoisting system must be carefully designed to ensure the efficient, reliable, and safe flow of material. Because shaft sinking and hoist installation can total between 2.5% and 3% of the cost of opening a deep mine, proper hoist selection is critical. Today's mining engineer has at his disposal the most powerful design and analytical aid ever, the microcomputer. There is, unfortunately, limited software for the study of hoisting systems, unlike that for other materials handling equipment (Manula and Albert, 1980; Prelaz et al., 1964; Bucklen, 1969; Thompson, 1985). HOIST reduces a time-consuming set of calculations to a concise package of interrelated subprograms. A literature review revealed no common-user programs to analyze hoisting systems, although at least four major hoist designers/manufacturers/installers have their own in-house programs. To provide a tool with which the mining engineer could preliminarily analyze a materials hoisting system or could check the calculations of a hoist contractor, a computer program was developed. HOIST was written in BASIC for the IBM-PC for ease of program adaptation and to encourage field use on compatible systems. Details of program development are omitted, since the basic principles of hoisting analyses are relatively straightforward, simple, and readily accepted (Harmon, 1973; Nordberg, n.d.; Adler, 1957). Program features, intended usage, and benefits of the computerized solution are emphasized over theory development and mathematical rigor. Background The mine hoist system that is selected and installed at a mine is the "lifeline" of that mine, with installations lasting 20 years or more. Thorough study is warranted to ensure that productivity demands are met at a minimum cost per ton. The increased cost of a large, powerful, high-speed hoist must be offset by increased production to justify its selection. To optimize this tradeoff, an extensive hoisting analysis should be performed. The analyses to properly size the skip (or cage), the drum, and the hoist drive are conducive to computerization, permitting rapid evaluation of changeable operating and design parameters, such as velocity, acceleration, state of balance, and productivity demand. The program is particularly useful in conducting sensitivity trials, such as investigation into the effect of change of productivity on skip capacity and on horsepower of the hoist drive. HOIST is currently limited to the study of drum-type hoists with cylindrical drum(s). However, only minor changes to the program would permit analysis of friction hoists and conical drum configurations. Model development and testing The program is based on accepted equations and physical relationships. Examples of manual calculations formed the basis for decision points and program branching. Data is input in the order that it would be needed if the problems were solved manually. The choices are arranged likewise. HOIST was developed in sections, with manual solutions performed to check program logic. The testing became more rigorous as sections were completed. Output from one section becomes input for following sections, as appropriate. The simplified flow diagram of HOIST is given in Fig. 1.

Jan 2, 1987

By Leigh Freeman

This article provides an overview for a series of leadership development workshops offered through the SME Young Leaders Program. The first of these workshops, “Accelerated Development Plan,” will be held at the upcoming SME Annual Meeting in St. Louis, MO on Sunday, March 26. How does a foundation of technical competencies relate to the development of social competencies necessary for management and leadership roles in the resource sectors? Technical competencies provide the foundation for a successful career. Social competencies provide the framework on that foundation. Successful leaders will be those who develop competencies in all areas.

Jan 1, 2006

By T. Pool

Introduction After two decades of contraction and consolidation, the uranium industry has seen a recent major expansion. Rapidly increasing uranium prices and the ability to raise speculative capital in share markets worldwide have brought over 300 new participant companies into the uranium industry: “juniors” as they are known. These companies participated in a global land rush for known deposits as well as for prospective land positions in order to secure a “piece of the action” for their respective portfolios. Mostly publicly-traded companies, these “juniors” have captured the attention of world’s investing public with spectacular gains; as much as 1,000s of percent in less than four years. The initial phase is over, however, and these companies must now prove that they can be successful in exploration or production.

Jan 1, 2007

The design/optimization of the pump and cyclones to maximize grinding circuit efficiency first requires a concise understanding of, and clearly defined specifications for, desired grinding circuit performance. Subsequently, the pump and cyclone performances that provide the desired grinding circuit performance can be defined. Once the performance requirements of each process unit are determined, selection of physical equipment parameters that will deliver those performances can be carried out. The Functional Performance Equation shows that there are two distinct efficiencies in closed circuit ball milling. One of these, ?Circuit Classification System Efficiency? (CSE), is the fraction of ?coarse? material inside the ball mill upon which grinding energy is deliberately expended, versus the remaining fraction of ?fines? or finished size material inside the mill, upon which grinding energy is wasted (on over-grinding). The role of the pump and cyclones is to maximize CSE, which is the desired grinding circuit performance. The obtainable, target CSE for any given circuit can be estimated, for example by referring to a plant data base of CSE?s. Design/optimization guidelines then allow us to specify the pump and cyclone performances that will achieve the target CSE. This paper outlines the step-by-step, systematic method of pump and cyclone selection which maximizes CSE. Numerous examples of its successful application are provided.

Jan 1, 2011

By H. Lyn Bourne

This is the fifth annual tabulation of mineral royalty information. This tabulation, like the previous editions, includes all of the earlier data. There are also 60 new entries. In addition to royalty information, some entries show the cost of purchased reserves. Two articles relative to the evaluation of minerals reserves appeared in December, 1986. R.H. Paschall (In the Aggregate, ME, p 1139) wrote a good article, although it lacked specific royalty data. However, this author takes exception to two ideas in Paschall's column. Paschall contends that the royalty rate does not affect the mineral appraisal. This present author could not disagree more. Paschall also claims the location of an industrial mineral deposit is the only serious or practical caveat in comparing royalties. Comments received here from readers helped make the list of caveats that are cited each year. The readers will decide which factors influence the mineral value for their commodities of interest. Paschall's point about the relationship of the parties who are negotiating a royalty agreement is important and very well taken. The other article, written by William Vernon (Pit and Quarry, December 1986), gives a step-by-step process on how to conduct a mineral appraisal. The article cites three reasons for an appraisal: transfer rights; collateral for a loan; and taxation. A fourth reason is to establish adequate compensation for reserves lost through condemnation. This author has appeared in several court cases where compensation for loss of mineral reserves through condemnation required a mineral appraisal. Royalty rate becomes an important factor in the appraisal process, although the Pit and Quarry article refers to that part of the valuation equation as "profitability." Both articles were well written and are recommended reading for those interested in mineral valuations. The same caveats that have appeared in previous columns relative to factors that influence the value of reserves are restated. The data in the table serve as a general reference and are not intended to present an absolute scale of reserves costs. Several factors influence the value of any mineral commodity. The factors include: • location/transportation - especially significant for most industrial minerals; • market conditions both for the commodity and the company acquiring the right to mine; • quality or grade of the deposit as it reflects the amount of processing/beneficiation necessary to produce the finished product; and • legislative restrictions and conditions for mining a given material at a given site. These and other factors will significantly influence the cost of reserves. The table shows the range of royalties and the variations in the basis of computing the fees. In a few instances, it gives the cost of acquired reserves based on purchase price and quantitative estimates of the material in place. The table lists the commodity in column 1, and the subsequent columns give: • the location by state, US geographic area, or Canadian province ; • the cost - R for royalty and P for purchased cost; • the year in which the lease or purchase agreement occurred; and • comments or footnotes for more information. The cost column requires more explanation. The units may refer to cubic yards (/cu yd), cubic feet (/cu ft), short tons (/T), or acres (/A). 1 cu yd = 0.76 M2 1cuft = 0.28m3 1 st = 0.9072 t 1 acre - 0.4047 ha or m2

Jan 7, 1987

By Donald W. Stever

In 1995 I was asked to participate in a litigation matter between a corporation and its insurance carriers concerning insurance coverage for remedial costs at a large, environmentally contaminated closed-down former industrial facility. One of the buildings on this site became known to the lawyers representing the company as “the infamous Building 8”. This building housed millions of documents retrieved from various locations at the facility while it was being shut down. It became apparent that the facility management had no document destruction policy, and thus Building 8 contained internal memoranda, notes, copies of correspondence, permits, operating records, inventory records, and the like from fifty years of operation. Needless to say, some of these documents, all of which were subject to discovery by the insurance companies in the litigation, contained material that was less than helpful to the company’s case. Of course, there were also a few helpful documents, but the overall usefulness of these records was outweighed by the negative impact they had on the conduct of the litigation. A second example involves e-mail. Several years ago, acting on an anonymous complaint that we later discovered was made by a disgruntled former employee who had been fired, a small army of federal environmental investigators descended on a client’s operating facility and, armed with a search warrant, literally commandeered the facility’s EH&S department. The investigators impounded the computers of the EH&S personnel and extracted all of the data from the hard drives of those PCs, as well as all EH&S related files from the hard drives of several servers used by the facility. These computers contained many years’ worth of stored e-mails, draft letters and memoranda, and other documents that provided grist for a four and one-half year criminal grand jury investigation of the facility and its EH&S staff. Both of these companies would have benefited from following a rigorous, enforceable, corporate records policy. Here is a third problem. My client had, during the 1960s, made a brief, and unprofitable foray into the nuclear fuel processing business. It ultimately sold the subsidiary, and was forced to give the purchasing company a broad indemnity against future liability. As might be expected, years later the facility was found to have considerable soil and ground water contamination both by chlorinated solvents and low-level radioactive material. Several years into the remediation program, my client discovered a tractor-trailer load of files, apparently removed from the subject facility, sitting in a parked trailer in a company-owned lot 300 miles away from the facility, where they had been for nearly thirty years. These documents were not helpful to the client, but had to be reviewed, at considerable cost, by paralegals. Moreover, several of the boxes turned out to have been mildly radioactive, setting off a chain of health and safety issues that consumed tens of thousands of dollars of legal expenses before they were resolved. Today, formal, enforceable corporate records management programs have become an extremely important element of overall corporate management. What was for most of the last century little more than a low level warehousing function is now a critical, actively managed, operating function that affects every level of corporate management. The rapid assimilation into corporate culture of electronic document management and the prevalence of e-email as the primary means of internal communication have created records management complexities the likes of which were not even conceived of fifteen years ago. Record preservation and destruction are no longer matters that can be handled on an ad-hoc decision making basis. Because of regulatory requirements affecting various classes of documents and the litigation consequences of ad hoc retention and destruction of corporate business records, and the need to have the ability to quickly retrieve documents in either a litigation or business negotiation context, a set of records management norms have evolved over time that have become the core elements of virtually every corporate records program. However, notwithstanding the existence of a set of norms (which are the basic elements of a

Jan 1, 2005

In the last four years, 2007~2010, 9 out of 24 metal/nonmetal underground mine fatalities were caused by ground fall across United States of America (Mine Safety & Health Administration, MSHA). To reduce or eliminate incidents/accidents caused by ground fall, this paper clarified how to design and select ground support based on different ground conditions, how to use mine ground support standards, what geotechnical engineers and underground operators should do to keep mine production free of ground failures.

Jan 1, 2012

By Lee Browne

The transformation of Peru’s Tintaya copper project from a state-owned company to a private company is under way and the results have been successful. Since Magma Copper Co. assumed operating management in December 1994, production and costs have improved dramatically. To understand the transformation of Tintaya, the transformation of Magma Copper must also be understood.

Jan 1, 1996

By H. Hamza

Oil sand tailings are disposed of in large ponds in which MFT (Mature Fine Tailings, a stable suspension of fine particles in water) forms after many years of settling. Long-term storage of large volumes of MFT is costly to maintain and also poses an environmental liability. The Advanced Separation Technologies laboratory at CANMET Western Research Centre has worked closely with oil sand companies to eliminate MFT generation by applying paste technology to oil sand tailings. In this process the fine tailings are flocculated to produce a thickened material that has the potential to consolidate to a dry landscape, while warm water is recovered and recycled for reuse in the extraction process. This paper presents some results of an extensive technical program involving bench-scale tests for flocculant selection and continuous thickener pilot tests.

Jan 1, 2002