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By Richard E. Deery, Reginald E. Reid

A large portion of the public lands in the United States is managed by the U.S. Department of the Interior, Bureau of Land Management (BLM). Public lands administered by the BLM comprise about 39 per cent (270 million acres) of the entire Federal surface estate or about 1/8 of the surface of the United States. Most of this land, located in the 11 Western States, including Alaska, is available for mineral exploration and development. The BLM is a multiple-use land management agency responsible for the balanced management of the public lands and their resources. The BLM's task is to ensure the balanced and sustainable development of the public lands and resources. This task translates into the management of people and their use of the public resources. As a result, the BLM manages a diverse group of programs including recreation, range lands, timber lands, fish and wildlife habitat, watershed, wilderness, scientific, cultural, and historic properties, and most importantly for this paper, energy and mineral resources. The BLM has developed several new policies with respect to mining, including policies on inspection and enforcement, financial guarantees for reclamation, and the use of cyanide. The goal of these policies is to demonstrate to the American public that mineral exploration and development can be an integral part of sustainable development on public lands in an environmentally sound manner.

Jan 1, 1991

By D. L. Misterek, E. J. Slebir, G. W. Ring, M. A. Laird

INTRODUCTION In 1973, the Federal Highway Administration (FHWA) initiated a 10-year program of research on tunneling technology for future highways as a part of a larger Department of Transportation effort on tunnels. The objectives of the FHWA program are to: improve tunnel design technology, reduce costs, minimize adverse environmental impact due to construction, increase the rate of construction, and assure the maintenance of a safe and attractive tunnel environment. The program is divided into four research tasks designed to solve tunneling problems identified by the engineering and field offices of the FHWA. These tasks are as follows: 1. Cut-and-Cover Tunneling 2. Site Investigations 3. Ground Movements - Prediction and Control 4. Highway Environmental Criteria for Tunnels In order to provide input into Tasks 2 and 3, the FHWA is sponsoring an investigation and testing program by the U.S. Bureau of Reclamation to instrument and monitor two sites in the second bore of the Eisenhower Memorial Tunnel located on Interstate Highway 70 at Loveland Pass approximately 97 km (60 miles) west of Denver, Colorado. The tunnel will be approximately 14.0 m (46 ft) in diameter when excavated. The study is designed to generate data on: (1) changes in the state of stress, and movements during and after tunneling, (2) tunnel lining design requirements, (3) developing a

Jan 1, 1976

By J. J. Scott, G. H. Bennett

INTRODUCTION Friction Rock Stabilizers, commonly called Split Sets,tm* have been under development since early 1973. Five years of intensive laboratory and field testing led to their introduction to the metal mines in the United States in the fall of 1976. Actual sales started in February of 1977 and, to date, over five million units have been marketed to metal mines. The present rate of useage is near 3 1/2 million units per year which is approximately 50 per cent of all roof fixtures used in the United States metal mining industry. Mr. Richard Hoppe, Senior Editor of Engineering & Mining Journal, in an article of the February, 1979, issue, entitled "Winning the Battle Against Bad Ground", said, "In hardrock mining operations in the western U.S., particularly underground uranium mines where exceedingly difficult ground is common, no roof support system has been accepted more quickly than the Split Set friction bolt invented by Dr. James J. Scott and developed by Ingersoll-Rand Co." This paper describes how Friction Rock Stabilizers function and presents technical data to show the uniqueness of the Friction Stabilizer system. SPLIT SET STABILIZERS The Split Set System is a revolutionary development in the field of ground control. The system produces an interior reinforcement to a rock mass which: *Trade Mark of Ingersoll-Rand Co.

Jan 1, 1979

By Nancy J. Wheatley

I. INTRODUCTION The Massachusetts Water Resources Authority (MWRA) is a regional water and sewerage authority which provides wholesale water and sewer services to the Metropolitan Boston area. The MWRA was created by the Massachusetts Legislature as an independent authority in 1985 following the filing of a lawsuit in federal court to correct the pollution of Boston Harbor resulting from inadequate and inadequately maintained sewerage facilities. Immediately upon its creation, the MWRA began to tackle treatment plant issues, including addressing the need for a secondary treatment plant, planning for ceasing ocean discharging of sludge, and making interim repairs to the existing, antiquated treatment plants. The MWRA's initial activities led to a court-ordered schedule for construction of a single new primary and secondary treatment facility, for development of sludge management plan focussed principally on reuse, and for completion of a short term program of repairs to existing facilities. Once a schedule for completing these activities had been negotiated, the U.S. Environmental Protection Agency (EPA), a plaintiff in the federal court case, asked that the MWRA take "responsibility" for controlling discharges from combined sewer overflows (CSOs) within its service area. Combined sewers (sewers in which both sanitary sewage and storm water runoff are carried in a single pipe) presently discharge over 10 billion gallons of untreated wastewater into Boston Harbor and its [ ]

Jan 1, 1991

By DING TANG, JINGHE CHEN, Shuiping Zhong, CHEN KUANG

The Zijinshan gold-copper mine, located in Shanghang County, China, is a porphyry-type, low-grade ore deposit with a geological profile of upper gold and lower copper. Despite its low-grade nature, it has become one of the largest in production scale and most profitable nonferrous metal mines in China, which can be attributed to the successful application of hydrometallurgy as well as proper engineering design. A large-scale, open-air cyanide heap leach has been successfully implemented to recover gold under the humid and rainy weather conditions of southern China. Furthermore, according to the gold ore characteristics, a combination of gravity separation, carbon-in-leach and heap leaching processes was developed to improve gold recovery. In terms of copper extraction, copper ore of a grade higher than 0.25 percent is fed to the flotation plants to produce copper concentrate (gold is also enriched here), while copper ore of a grade lower than 0.25 percent undergoes heap bioleaching followed by solvent extraction and electrowinning to produce cathode copper. Additionally, a unique bioleaching system has been established at the Zijinshan Mine: low operating pH (0.8~1.0), high concentration of total soluble iron (~50 g/L), high temperatures (45~60 °C) and low activity of microorganism (~104/mL) in the pregnant leach solution (PLS). This review paper summarizes the practical experience acquired in developing the Zijinshan gold-copper mine and could be of use in other gold and/or copper plants.

By Michael N. Maltezos

"There is certainly no argument that LED lighting systems have taken a strong foothold in the lighting marketplace over the last several years. This has even proven true in the world of transportation and transit lighting, for which new LED cobra head style luminaires are replacing traditional HID cobra head luminaires on North America’s roadwaysand linear LED light fixtures are replacing conventional linear fluorescent light fixtures in North American rail transit facilities. However, LED technology has taken a while longer to penetrate the very specific market of vehicular tunnel lighting in this continent. Though both the New York/New Jersey Holland and Lincoln Tunnels have recently been retrofitted with LED lighting, and an LED Lighting RFP is currently out for Boston’s Central Artery Tunnels, very few vehicular tunnels in North America to date have been illuminated with LED light fixtures. This is largely because cost effective LED lighting, that met our typically stringent tunnel lighting standards, was until recently simply unattainable. However, with the rapid advances in LED technology over recent years, owners and specifiers of North American tunnel lighting projects have finally begun to adopt LED lighting systems as the norm. In fact, a recent Lux Fit/Yole Development “LED in Road and Street Lighting Report” stated that “LED luminaire growth will be driven firstly by tunnel lighting, and then relayed into highway, road, residential and amenity lighting applications starting in 2014.” 1 Our highways are continually becoming more congested. As a result, Provincial and State Departments of Transportation (DOTs) are constantly looking for innovative ways to improve traffic flow. One way DOTs are now helping to ease congestion is by expanding the use of tunnels and long underpasses in large interchange reconstruction projects. With less available right-of-way to work with, and the high costs of maintaining elevated bridge structures over the years, it often makes more sense to “go under” (rather than over) the traffic congestion points. With the addition of these new tunnels and long underpasses comes the issue of proper illumination within these structures, for a safe and efficient driving task. DOTs use recommended lighting practices and guidelines for highway lighting, which include specific criteria for tunnels, set by either the Illuminating Engineering Society of North America (IESNA) or the American Association of State Highway and Transportation Officials (AASHTO). However, both IESNA and AASHTO point out that these recommended practices and guidelines are not a mandate, and DOTs are free to make their own decisions about lighting criteria. Accordingly, effectively illuminating tunnels is often times a challenge. This paper will examine the key considerations of the tunnel lighting application in generalas well as what LEDs now bring to the table and how, accordingly, traditional lighting technologies will be phased out in the future illumination of tunnels."

Jan 1, 2016

By Robert R. Brandom

The Boss-Bixby deposit is one of several iron deposits that occur in the Precambrian igneous rocks of southeastern Missouri. It differs, however, from all of those deposits by its significant contents of copper, cobalt, and titanium, and its close relationship with a basic igneous intrusion. Ore microscopic study of selected drill core samples has shown that the hypogene ore minerals are magnetite, hematite, chalcopyrite, bornite, covellite, ilmenite, rutile, sphalerite, cobaltian pyrite, carrollite, scheelite, and wolframite. Subsequent partial oxidation has formed martite, pseudobrookite, and anatase. Textural evidence indicates that two stages of iron and iron-titanium oxide formation were followed by the deposition of the copper-iron sulfide minerals and carrollite.

Jan 1, 1985

By A. Tordoir, S. S. Kanchibotla, W. Rogers, E. Engmann, B. Bisiaux, S. Ako

Blast-induced rock mass displacement can have a significant impact on ore loss and dilution. The mischaracterization of the grade boundaries both prior to, as well as a result of, blasting can lead to significant financial losses due to ore loss and dilution. Ore dilution occurs when waste material is miscategorized as ore and sent for processing or stockpiling, diluting the run-of-mine head grade and recovery. Ore loss takes place when valuable mineral is miscategorized as waste and sent to the waste dumps, thus never being processed and recovered. Extensive research has been conducted at the University of Queensland over the last fifteen years to understand the impact of blast movement on ore loss and dilution. Recent outcomes of this research have led to the development of innovative tools and techniques to measure and model blast movement. These techniques have been implemented at the Ahafo gold mine in Ghana to understand blast movement dynamics and to implement solutions to reduce blast-induced ore loss and dilution. These solutions are validated through controlled trials and have been incorporated into site standard operating procedures.

Jan 1, 2012

By Ch. Apostolaki

Eighty samples from Roman wall paintings from ancient Corinth were studied by means of optical and scanning electron microscopy coupled to an energy dispersive analyzer, X-ray diffraction and image analysis techniques. The goals of the study were the identification of the exact nature of the pigments and the technical features of paint application (binding medium, adherence to plaster, thickness of the pigment layer), which would provide evidence about the painting technique (fresco or secco). The main plaster is calcitic with secondary calcite as a cement binder to the primary calcite grains. All pigments, except Egyptian Blue, were naturally occurring ochres or pigment minerals, such as limonite, goethite, hematite for yellow, brown and red hues, cinnabar for red hues and celadonite for green color. The presence of specific elements such as Ni and Cr or minerals such as olivine, in the yellow, brown and red pigments, gave an indication about the provenance of the original pigments, which seems to be from Cyprus. The black color was represented using charcoal. It seems, finally, that for the pigment application the fresco technique was used, while secco is also apparent.

Jan 1, 2006

By Joseph G. Carleton

INTRODUCTION The increasing concern for the environment may well present far more opportunities than problems for those involved in all phases of tunneling. All too frequently in the past, environmentalists and their concerns have been cast in a negative light, as obstacles to be overcome. Often forgotten is the fact that these same environmental concerns have created a rapidly increasing demand for new tunnels. Tunnels for rapid transit projects, clean water supply, and sewage treatment have been given a boost because of environmentalists' concerns about overuse of automobiles, inadequate water supplies, and improper sewage disposal. Concurrent with increasing use of tunnels to help solve or alleviate some of our environmental problems is an obligation not to create new ones in the process. Concerns which we feel responsible tunnel owners, engineers, and contractors should address themselves to include: (1) Minimum energy consumption, both during construction and in operation of the completed project; (2) proper storage and/or disposal of the excavated material; (3) minimum disruption during the construction process - noise, traffic, unnecessarily unsightly work areas, and possible weakening of foundations of nearby structures; and (4) a finished project consistent with community and environmental goals. We are especially concerned about two things. First, the longrun implications of a project -- what's good for a few people in the short-run may be bad for most of the people in the long-run. Cutting corners to save a little money now is false economy. Second, the fact that ultimately we all share the same earth -- its water, air,

Jan 1, 1974

By Didem Maral

Olivine is a name of a mineral group that has a chemical formula of: (Mg, Fe), SiO4. The most important rock for the olivine group minerals is dunite, which can contain olivine up to 95-99%. Dunite can be obtained from chrome enrichment as a by-product. As a result of alteration of the olivine group minerals, several kinds of different minerals can occur. Main consumption areas of olivine are steel and iron industry. Also olivine is used in not only casting and refractory industries but also production of radiator, ballast material and abrasive. North of Bursa-Orhaneli has got more than 5 billion tons reserves in ultrabasic massifs. M.T.A found that olivine has got high quality of using in refractory and casting industry.

Jan 1, 2005

By P. Shang

Fly ash and zeolite have strong absorption to cations since their porous microstructure. The porosities of fly ash and zeolite can also be increased by modification, which improves the absorption of the materials. This research showed that the effects of modified fly ash and zeolite to remove ammonia nitrogen from rainwater. The optimal reaction time, additive amount of materials, and pH value of the stormwater to remove ammonia nitrogen were experimentally determined. For modified fly ash, the optimal removal rate of ammonia nitrogen from 100 ml stormwater was 74.41% with the addition of 10.0g fly ash, 1.5 hours of the reaction time, and 8 of pH value. To the modified zeolite, the optimal removal rate of ammonia nitrogen was 51.22% at the reaction conditions of 2.0g of zeolite, 1 hour of reaction time, and 7 of pH value.

Jan 1, 2010

By A. De Daio, D. W. Fuerstenau, P. C. Kapur

Because of its pronounced tendency to undergo visco-plastic flow, coal ground in the energy- efficient high-pressure roll mill invariably comes out as a briquetted product which must be disintegrated in a conventional type of grinding device such as the ball mill. The aggregates comprise comminuted coal particles that are apparently extensively cracked and weakened during passage of the coal through the high-pressure rolls. Their deaggregation in a ball mill in the second stage is accompanied by further grinding of the coal with a relatively small expenditure of energy. Thus in spite of energy dissipation in briquetting in the roll mill and in disintegrating the briquettes in the ball mill, significant energy savings are possible in the fine grinding of coal in a two-stage serial grinding mode, as compared to ball mill grinding alone. It has been determined that for the best results the energy invested in the two grinding stages must be apportioned in an optimal manner, the energy consumption in the ball milling step is comparable to, even in excess of, the energy spent in the high- pressure roll mill; and 20 to 50 percent energy savings might be possible in grinding coal to minus 200-mesh size by this two-step process, as compared to conventional milling.

Jan 1, 1995

By G. G. O. O. Uwadiale, M. A. U. Nwoke

The flotation of Azara barite tailings was investigated using crude rubber nut oil (RNOc), refined rubber nut oil (RNOR) and oleic acid as fatty acid collectors. Chemical characterization of the rubber nut oils indicated high acidity, high saponification values and high iodine indexes, which are indicative of a high fatty acid compositions. The Azara barite tailings analyzed 64.6% BaSO4 by atomic absorption spectrophotometry. Gravity and magnetic separation techniques yielded a BaSO4 concentrate with a grade of 74.8% and a recovery of 92.5%. Barium sulfate grades of 90.0%, 92.8% and 94.8% with recoveries of 80.3%, 85.4% and 86.7% were achieved with collector dosages of 750g/t crude rubber nut oils, refined rubber nut oils and oleic acid, respectively. Hence, rubber nut oils are effective fatty acid collectors for the flotation of barite tailings.

Jan 1, 1998

By Roger A. Kauffman, Dean Van Dyk

Feldspar is the earth's most abundant mineral group. The feldspars are aluminum silicate minerals belonging to the tectosilicate class. Feldspars are the most widespread of any mineral group and are estimated to constitute 60% of the earth's crust. They make up a large percentage of the exposed rocks as well as soils, clays, and other unconsolidated sediments. Feldspars are widely used in the glass and ceramic industry and are principal components in rock classification schemes. Feldspar minerals and their production are important contributors to the domestic and world economies and standard of living. In 1990, the United States produced 630 kt of feldspar minerals, and world production was estimated to be more than 5 Mt. Feldspar mineral production in the United States has a long and interesting history (Feitler, 1967, Rogers Jr. et al., 1983). The first commercial production in the United States occurred in about 1825 and came from pegmatite bodies located in Connecticut, where feldspar was mined, hand sorted, and shipped to England. Feldspar production grew during the 19th and 20th centuries with important developments in production location, integrated mine and processing facilities, and the development of the flotation process for feldspar by the US Bureau of Mines and the feldspar industry. The first commercial feldspar flotation plant began operations-in Kona, NC, in 1946, some six years after this process had been developed. In 1990, the domestic feldspar industry consisted of 12 operating companies with mines and processing plants located throughout the United States (see Table 1). During the last 25 years, the domestic feldspar industry has been dynamic, marked by new plant construction and capacity expansion at older plants. The industry has also seen plant closures, changes in ownership of existing operations, the consolidation of the Canadian nepheline syenite industry, and the increase of imported feldspar products. The industry has been affected by contractions in its major end-use markets brought about by economic cycles, product substitution, and environmental effects, such as recycling, land-use controversy, and air and water pollution. Despite problems, the industry remains mature and highly competitive. GEOLOGY Mineralogy The common feldspar group of minerals form a single crystalline phase or solid solution series of minerals. Fig. 1 is a ternary phase diagram that shows the feldspar mineralogy-KAlSi,O8, NaAlSi3O8, and CaAl2Si2O8. The end-member compositions are also referred to as potassium, sodium, and calcium feldspar. The feldspars whose chemistry ranges between the potassium and sodium end-members are known as alkali feldspars, while those between the sodium and calcium end-members are plagioclase feldspars. These feldspar groups can be further subdivided based on structural and compositional features within the alkali or plagioclase feldspar series. The distinction between and the proportion of members of the two feldspar groups are important to the classification of igneous rocks (Deer et al., 1966). Perthites are the exsolution product of an initially homogeneous potassium-sodium feldspar solid solution which forms (in an environment of decreasing temperature) a heterogeneous intergrowth of sodium-rich feldspar lamellae in a host crystal of potassium feldspar. Antiperthites are exsolution products in which the host mineral is sodium-rich plagioclase feldspar and the intergrowths are potassium-rich feldspar.

Jan 1, 1994

By Y. V. Vasylchuk

An algorithm is presented for optimizing the classification of surface mine material subject to excavating constraints. High-resolution, expected-profit models are optimized to classification maps subject to site-specific excavating constraints. This optimization problem defies traditional closed-form analytical solutions. A practical heuristic algorithm quickly determines the optimum final destination for material subject to realistic selectivity constraints. The expected profit could be calculated from an estimated model if the value calculations are all linear; otherwise, simulation could be used. In both cases, a single expected profit for all destinations on a high-resolution grid is the starting point for dig limits optimization. Maximizing expected profit in a risk-neutral manner is correct given the repeated nature of grade-control decisions over relatively short timeframes.

By Jack Bradbury

The open stope room and pillar method of mining is used throughout Ozark Lead Company's underground mine located at Sweetwater, Missouri. This method of mining produces an approximate overall ore extraction of 80%. Pillar recovery, on a limited and experimental basis, was started in January of 1979 to determine the maximum size underground opening that could be mined safely. Monitoring the roof and surrounding pillars for potential failure during this pillar recovery process was accomplished by utilizing a simple rod extensometer to measure roof sag. Boreholes 7.5cm in diameter were drilled 3.5m into the roof to spot any separations or cracks that might have propagated between the bedded layers of rock. Underground openings 85m in length by 46m in width have been mined successfully without roof or surrounding pillar failure. Continued measurements to establish long term results will be necessary.

Jan 1, 1981

By Kenneth Maser, Douglas W. Ounanian, Joseph S. Boyce

Foster-Miller Associates, Inc. (FMA), under contract to the Department of Transportation (DOT) and the Urban Mass Transit Administration (UMTA), is currently developing an Extruded Tunnel Lining System (ETLS). The ETLS would reduce ground support costs in machine bored tunneling by eliminating the need for temporary support, and by slip-forming the final concrete lining directly behind the Tunnel Boring Machine (TBM). The system can advance at variable rates, from 0.6 to 3.7 m (2 to 12 ft) per hr, by combining three systems: a very high early strength concrete, continuously produced and delivered by a concrete process system; a slipform/bulkhead system for supporting the concrete prior to strength gain and exposure; and a control system for form/bulkhead alignment and concrete process control. Large-scale tests are planned to demonstrate the system in a 3 m (10-ft) diameter steel "tunnel".

Jan 1, 1981

By J. Gonzales

For this paper, blending is conceived as a linear process that takes a proportion from one stockpile or location and mixes it with another proportion from another stockpile or location, with the aim of obtaining a set of attributes in the final combination that satisfies a given quality standard. A blending class is the combination of ore attributes and grade limits that should be stockpiled in order to achieve the target quality for the process Plant. Current literature considers the number of blending classes in the Open Pit Scheduling Problem as fixed; however, this paper shows how to define specific blending classes for a given deposit so that the schedule can be solved with Sequential Linear Programming. Finally, a practical application in a Peruvian copper mine is shown, involving four ore attributes: alteration code, arsenic, oxide content and copper grade. INTRODUCTION In copper ore deposits, blending for quality has not been a typical issue as it was for coal and iron ore; however, current copper deposits in the world are becoming geologically and chemically more complex than in the past and is not uncommon to have quality standards involving up to four attributes, introducing an additional complexity to the mine scheduling process [1]. In order to solve the Open Pit Scheduling Problem with multiple ore quality constraints, two assumptions are necessary [2]: - Grade constraints are defined only by specifying an upper and lower limit; - Ore attributes in stockpiles are pre-determined, i.e., the upper and/or lower grade limits defining each stockpile are already known at the time of setting the schedule. Assuming each ore attribute is classified as high, medium or low, and there are four attributes to be controlled in the target ore quality, the number of possible blending classes would be 3^4 = 81. This number is impractical to manage in Operations, and increases the complexity at the time of running the schedule; therefore, a more efficient way of classifying ore is required. Note that in practice, one blending class can be split into more than one stockpile location due to physical capacity constraints. Therefore, the number of stockpiles could even be more than 81. BLENDING CLASSES DETERMINATION For a given set of ore grades with lower and upper limits to be achieved, one has to find all feasible ore classes such that when blended, their grades will lie within those limits.

Jan 1, 2019

By John D. Shaw

1. Introduction 2. The Hydraulic Mine _ (i ) Development (i i ) Extraction ( i i i ) Transport 3. The Water Circuit 4. Manpower and Results 5. Modifications 6. Conclusions 1. Introduction The Kaiser Resources Ltd. hydraulic coal mine is located in south eastern British Columbia, Canada, at the western end of the Crowsnest Pass, next to the Town of Sparwood. The seam presently being mined is the number 10, known locally as the Balmer seam, which is a high quality coking coal, 50 feet in thickness and of an average inclination of 35 degrees. The mine was designed in the late sixties as a small scale trial unit, and was to use a single monitor unit, working 3 shifts per day on a 5 day per week basis. Experience has proved the method to be so successful as to warrant the expansion of the ancilliary facilities to cater for the increased production. The annual raw coal production from this single monitor unit has risen from 108,988 short tons in 1970 to 942,334 short tons in 1975, with a total mine labour force of about 160 men including the surface de-watering plant, mine supervision and mine administration.

Jan 1, 1977