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By D Beahm

Introduction The Energy Metals Corporation (EMC) holds numerous mineral properties in the northern portion of the Great Divide Basin including the JAB Property, one of several potential properties being planned for development as a satellite facility to the greater Antelope Uranium Project. A National Instrument 43-101 Technical Report has been completed for the JAB property. This report estimates total measured and indicated mineral resources on the property totaling 3,555,022 pounds U3O8 contained in 2,400,875 tons at an average grade of 0.073 % U3O8 at a .25 GT cutoff in accordance with CIM Standards on Mineral Resources and Reserves. The JAB Property is located in Sections 13, 14, 15, 16, 21, 22, and 23, Township 26 North, Range 94 West, approximately Latitude 42o 14’ North and Longitude 108o 00’ West (Figure 1, Location Map). This property consists of unpatented mining lode claims and Wyoming State mineral leases comprising approximately 2,100 acres.

Jan 1, 2007

By Tim O’Neil

Tire companies have historically used the mining industry as a platform to launch new technologies. And the mining industry has been receptive to that. So, while developing its Two Piece Assembly, Goodyear noted a number of trends in the mining industry: •The global market sophistication of equipment and operations requires the packaging of products and services to provide the best return on investment. •Industry consolidation and growth have resulted in fewer, more powerful mining houses, leveraging purchasing power in the marketplace. •User productivity demands continue to drive original equipment manufacturers to develop higher pay-load equipment. •Technology needs include improved ergonomics, to reduce fatigue and increase operator productivity. •Increased laws and environmental regulation prohibit on-site whole tire disposal practices.

Jan 1, 2003

By W. V. Swarzenski

In its, effort to combat waterlogging and coil salinity, the later and Soils Investigation Division of WAPDA (West Pakistan's Water and Power Development Authority) has carried out an extensive program of test drilling and water sampling, since 1954. Data collected during the past ten years have permitted the delineation of fresh and saline ground-water-zones in the Punjab Plain. Fresh ground water containing generally, less than 500 ppm (parts per million) of total dissolved solids is found in wide belts paralleling the major rivers and in other areas of fresh-water recharge. Locally, fresh ground water extends to depths of 1,500 feet and more. Saline ground water occurs downgradient from sources of recharge, particularly in the lower central parts of the interfluvial areas and, presumably, underlies most of the Punjab Plain. The ground waters of the Punjab are characterized by their evolution from calcium, magnesium bicarbonate waters, near sources of recharge, to waters containing a dominant proportion of sodium. The highly mineralized waters of the Punjab are generally of the sodium chloride type, whereas in Dera Ismail Khan District sodium sulfate waters predominate. The pattern of distribution of saline ground-water zones and the observed gradual increase in mineral content, downgradient from sources of recharge, can be explained best by a hypothesis stressing the processes of evaporation from the water table and solution of minerals within the alluvial aquifer.

Jan 1, 1967

By R. M. Cox

The ground forces generated by a properly installed and tensioned mine roof truss assembly can provide permanent mine roof support, even in severe ground conditions, either by direct suspension of the rock loads within the potential failure zone above the mine opening or indirect reinforcement of the natural rock arch that tends to form within the immediate mine roof. Notable advancements in mine roof truss support systems hardware and design technology have occurred since the introduction of the in situ mine roof truss concept for permanent mine roof support in 1966. The systematic installation of mine roof truss support systems has proven to be a very effective method of mine roof control room and pillar mines under a wide variety of ground conditions, even in areas otherwise considered unmineable because of severe roof control problems. Properly designed mine roof truss systems have also been used for permanent support of mine slopes and haulage tunnels.

Jan 1, 2002

Once every three years the eyes of the construction and mining industry?s turn to Munich, Germany for the bauma trade fair and exhibition. From April 19-25, Messe München International (MMI) will host the 29th edition of this massive show that, despite the recent recession and global financial struggles, has grown yet again. The show, which is completely booked, will take place on a record 555,000 m2 (5.9 million sq ft) of indoor and outdoor exhibition space at the New Munich Trade Fair Centre. More than 3,000 exhibitors are expected to make use of this event. To prepare for the show that highlights some of the largest and most impressive construction and mining equipment in the world, Messe München began working months in advance on getting the infrastructure on the open-air site ready, in time for the arrival of the gigantic machinery exhibits, which started to arrive in March. Part of the preparations include a new entrance at the northwest corner of the exhibition center that was built to regulate visitor flow better. This should help with bauma considering that in 2007 more than 500,000 visitors passed through the gates. ?Although in 2010 the construction machinery sector in many markets worldwide will be recovering only slowly from the recession, we are pleased to report that we are seeing strong demand for exhibition space. This shows that exhibitors regard participation in the world?s leading trade fair bauma as a must, although many are at present having to make cuts in their advertising and trade-fair budgets. We have been particularly surprised by the strong demand for space from exhibitors from markets like China, India and Turkey. The fair is fully booked and many more companies are on the waiting list,? said Eugen Egetenmeir, managing director of Messe München. More than 50 percent of the exhibitors at bauma 2010 come from countries outside of Germany. While the show?s primary focus is on the construction section, it is not as if the mining sector will be difficult to find. With some of the largest equipment in world on display in section C2 (Fig. 1), the mining industry is sure to be well-represented.

Jan 4, 2010

By Carl Pinches

Underground or surface mining is only the first stage in the ore mining process. Once the ore is mined, it is transported to the surface for further processing. Generally, this is done to extract the particular metal or other component of the ore that has commercial value in its purified form. In its raw state, there are typically between 4 and 7 g/t (0.12 and 0.2 oz/st) of valuable material from rock mined. Once on the surface, the ore is crushed and milled in order to obtain smaller rock particles and to expose the minerals that contain the desired metal or component. Mixing the milled ore with water, a process known as ?froth flotation,? can be employed. This technique consists of a series of tanks, or ?cells? through which the process liquid flows. To obtain the maximum recovery, the milling and flotation process will often be repeated a second time. An increase between 100 and 1,000 g/t (2.9 and 29 oz/st) of rock following this stage of the process is typical. Efficient recovery is key to maintaining a profitable mining operation. The measurement and control of the froth flotation process is vital.

Jan 1, 2010

In the dimension stone industry, workers in processing shops may be exposed to harmful levels of respirable silica dust when conducting the different tasks in stone preparation, which include cutting, grinding, polishing, and thermaling. To protect workers from this health hazard, operators sometimes ventilate processing shops using fan-powered dust collectors to capture and filter dust. To investigate this issue, NIOSH, Pittsburgh Research Laboratory, in cooperation with a dimension stone operation, upgraded an off-the-shelf dust collector the operator was utilizing in a polishing/cutting shop. Initial dust surveys showed that the unit was under-designed for the amount of dust being generated in the shop. The objective of the research was to cost-effectively increase the air cleaning volume and improve dust capture efficiency of the unit with a larger motor and blower. The unit?s original stock 0.56 kw motor and blower was replaced with a 2.24 kw motor and matching blower to increase airflow. The unit was evaluated both in the laboratory and the shop before and after the retrofit to determine the improvement of the upgrade. The study showed that the 2.24 kw upgrade improved the performance over the original 0.56 kw motor resulting in more dust being cleaned from the ambient air in the shop. The 2.24 kw unit cleaned 19% more air and captured 32% more respirable dust than the 0.56 kw unit.

Jan 1, 2009

By Karen Mikkola, Gerald Luttrell, Jaisen Kohmuench, Glen Oswald, Michael Mankosa, Tracy Westerfield

Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. Two of the most promising technologies, the CrossFlow and HydroFloat separators, have now been tested at industrial sites. The data obtained from these sites have been used to illustrate the potential performance improvements that can be realized through the application of these high-efficiency separators.

Jan 1, 2005

By Irwan S. Halim

For tunnels in horizontally bedded rock, geologic factors affect the selection and design of the initial supports, including the rock propensity toward parting along bedding and the resulting high potential for rock slabbing during excavation. To evaluate this ground behavior, numerical analyses and results with Mohr-Coulomb, Hoek-Brown, and Ubiquitous Joint constitutive models were used, using the Upper Rouge CSO tunnel in Detroit, Michigan as an example. The different rock models and other geologic considerations are shown to impact the selection of the tunnel initial support and design. This paper emphasizes the appropriate selection of an analytical model based on the site specific geology to achieve an optimum initial support design.

Jan 1, 2008

By H. Lowers, B. Van Gosen

The Iron Hill (Powderhorn) carbonatite complex is a 31 km2 alkalic intrusion located about 35 km south-southwest of Gunnison, Colorado. The intrusion has been well studied and described because of its classic petrology and architecture of a carbonatite-alkalic complex. The complex is also noteworthy because it contains enrichments of titanium, rare earth elements, thorium, niobium (columbium), vanadium, and deposits of vermiculite and nepheline syenite. In particular, the complex is thought to host the largest titanium and niobium resources in the United States, although neither has been developed. It may be economic to extract multiple resources from this complex with a well coordinated mine and mill plan.

Jan 1, 2007

By Wu Xueling

9K medium was used to isolate iron-oxidizing bacteria from 27 sump water samples collected from Dexing Cop-per Mine, Chengmen Mountain Mine and Yin Mountain Mine, Jiangxi Province, China. Lead acetate and silver nitrate were used to enrich metal-resistant iron-oxidizing bacteria from the above water samples. Isolate 16 was isolated from the sample taken at Dexing Copper Mine. Growth experiments indicated that when incubated under lead acetate (3,500 mg/L), isolate 16 still carried out ferrous ion oxidation, while isolate H1, a less resistant strain taken at Yin Mountain Mine, had a tolerance level of only 400 mg/L. When assayed with other metals, i.e., Ag+ (240 mg/L), Hg2+ (0.9 mg/L), Cu2+ (32,000 mg/L) and Mg2+ (22,500 mg/L), isolate 16 still carried out ferrous ion oxidation while, on the other hand, isolate H1 exhibited much lower tolerance levels, i.e., Ag+ (60 mg/L), Hg2+ (0.1 mg/L), Cu2+ (19,000 mg/L) and Mg2+ (13,500 mg/L). Based on 16S rDNA sequence data, isolate 16 and H1 were both identified as Acidithiobacillus ferrooxidans.

Jan 1, 2007

By Micheal Mitariten

The recovery of natural gas (primarily methane) from coalbed deposits is an established and growing source for the U.S and accounts for over 7% of its total production. The gas from on-purpose degassing is often pipeline quality and requires only compression and dehydration before being admitted to the pipeline grid. However, the raw gas is sometimes contaminated with nitrogen (N2) and/or carbon dioxide (CO2) that can make the gas inadmissible to the transportation pipeline. In general, the N2 must be 4% or less and the CO2 should be 2% or less. In treating gas produced from virgin coal bed or from degassing operations where CO2 is present, amine systems are traditionally used for its removal. Engelhard’s Molecular Gate® adsorption system offers an attractive alternative due to its skid-mounted equipment, low pressure and unattended operation, cost and high on-stream reliability. Natural gas can also be sourced from the residual coal, after the coal has been mined. This source can be the GOB or gas remaining in abandoned coal mines. This source is almost universally contaminated, often with a combination of CO2 and N2. If the source is from air intrusion, the source can also be contaminated with O2. In treating CO2 / N2 contaminated feeds, the Molecular Gate adsorption system removes both of the impurities along with a level of O2 within a single processing step. To date, ten Molecular Gate units are underway with three systems having been installed for upgrading gas from abandoned coal mines. The technology consists of specialty adsorbents and advanced PSA processes that are jointly offered as fabricated packaged equipment by Engelhard Corporation and Guild Associates, Inc. Upgrading requirements, project challenges and project arrangements are discussed in this paper.

Jan 1, 2005

Coal has been mined in the central Appalachian coalfields of southern West Virginia, western Virginia, and eastern Kentucky for more than a century. The dwindling reserve base consists in large part of coal that would have been considered unmineable by earlier generations. Nearly every current operation is working on a property where coal has been extracted in the past, from seams either above, below, or both. NIOSH is conducting research aimed at helping mine planners prevent hazardous conditions due to multiple seam interactions. To-date, more than 300 case histories have been collected from underground mines, mainly from central Appalachia. This paper focuses on several of the more challenging situations that have been encountered, including: • Room-and-pillar development 20 ft (6 m) beneath full extraction workings at a depth of 1,000 ft (300m) of cover (Virginia) • Pillar recovery 45 ft above full extraction workings at 900 ft (270 m) of cover (Virginia) • Near-simultaneous room-and-pillar mining with pillar recovery with 40 ft (12 m) of interburden and 1,500-2,000 ft (450-600 m) of cover (Kentucky) • Longwall mining directly beneath main entries in overlying seams (West Virginia) • Some of these operations have been highly successful in overcoming the challenges, others less so. The lessons learned from their experience will help ensure that these and similar difficult reserves can be mined safely.

Jan 1, 2006

By Verya Nasri

The Silver Line Phase III Project is the final one mile underground segment of the new Bus Rapid Transit in downtown Boston. The project is expected to significantly reduce existing and anticipated traffic congestion. The twin one-lane tunnels and two station platforms will be built by NATM in Boston saturated soft clay, sand and till layers in proximity to several historical buildings, underpinning two existing cut and cover subway stations and several major utilities in densely built urban area. This paper presents the analysis and design of the NATM tunnels and stations detailing the excavation sequence and support system and various ground improvement and pre-support techniques used in the preliminary and final design of the project

"Lax, misguided, and dangerous" is Rep. James Santini's description of the official US position on strategic nonfuel minerals. Santini (D-NV), chairman of the House Mines and Mining Subcommittee, criticized the Interior Department for "its long record of benign neglect" regarding the domestic minerals crisis. Santini made his remarks at a news conference at the American Mining Congress convention in San Francisco, where he released his subcommittee report "US Minerals Vulnerability: National Policy Implications." The report-said to be the first major congressional study of the minerals issue by a committee of jurisdiction is the result of a two-year inquiry. The investigation was undertaken, according to the chairman, "because no person or agency in the executive branch of government fully grasps the critical importance of nonfuel minerals to the nation's economy, defense, and quality of life." The report also urges a larger role for the Department of Defense, which has "stood passively by for many years as a consuming by-stander," according to the report. President Carter's incomplete Non-fuel Minerals Policy Review also drew the committee's ire; Santini calls it "a tragic waste that cost tax-payers $3.5 million and the loss of some 13,000 person-days." The subcommittee examined the following issues for its report: • The US minerals industry's inability to meet national raw material needs under a "hodgepodge of contradictory, restrictive, and irrational" federal regulations; • Dependency on foreign sources of strategic minerals in times of "increasing resource nationalism" and "Soviet mineral expansionism;" • National security needs for foreign mineral resources that do not have effective substitutes; • The US government's approach to national minerals policy "amid a growing realization that such a policy does not exist." The subcommittee report includes an analysis of public and private studies on nonfuel minerals and discusses a series of policy problem areas that negatively affect domestic production. Capital formation disincentives, tax policies, antitrust enforcement, environmental laws, health and safety regulations, technical problems, and restricted access to federally-controlled public lands contribute to what Santini calls a "tragic irony." "The irony is that we are a nation vastly rich in mineral resources yet our own government chooses to stifle development of these critical raw materials and thereby increase offshore reliance. The tragedy is that we also are ensuring US vulnerability to severe economic dislocations and a weakening of our national security." In just six years, from 1973-1978, the US trade deficit in nonfuel minerals rose from $2 billion per year to $8 billion, according to the report. The country imports more than 50% of 23 critical minerals, including 100% of its manganese, chromium, cobalt and platinum. The US is promoting its dependence on foreign mineral sources at the very time the security of many of those sources is becoming less certain, the report notes. Santini said the subcommittee investigation revealed a vulnerability that may be more serious and pervasive than that of foreign oil. The US may be able to develop alternate energy resources, but there are no effective substitutes for many nonfuel minerals. The report also discloses that US stockpiles of critical and strategic minerals are of inadequate supply and quality. Holdings of some vital minerals are far below present objectives, and for some there are no holdings at all, according to Santini. To resolve the current crisis, the report makes the following recommendations: • Complete immediately President Carter's Interagency Nonfuel Minerals Policy Review; • Implement (throught the Interior Department) the 1970 Mining and Minerals Policy Act; • Create an Office of Energy and Minerals with the same stature, power, and oversight responsibilities as the Council on Environmental Quality; • Ease federal restrictions on mineral exploration and development on public lands and implement a complete review of public land use policies; •Fund for and fulfill US nonfuel minerals stockpiling objectives; •Increase federal funding for non-

Jan 11, 1980

By N. O. Lotter

The reliability of a set of flotation results is key to minimizing project risk either at concentrator commissioning, or at the point of implementing an improvement to an existing concentrator operation. High-Confidence Flotation Testing was developed for this purpose, and is part of the list of technologies of various scales used by Xstrata Process Support (XPS) in addressing these projects. The methodology is based on two principles: one, to ensure that the ore sample is representative and has been well-blended and subsampled; two, to perform the flotation tests in sufficient numbers of replicates with appropriate quality controls, so as to improve the reproducibility of the test data. Across ten years of practice and continuous improvement with this methodology at Xstrata Process Support, Sudbury, several improvements to this method and complementary connections into sampling and quantitative mineralogy have been developed. Two case studies are reviewed. These show the capability of this system in both optimizing an existing concentrator operation and in serving a new mine scenario. Further work to improve the efficiency of this procedure has been identified.

Jan 1, 2009

By R. J. Hickson

From 1993 through 1999 Cyprus Amax Minerals Company successfully completed eight major construction projects around the world. Six greenfield mines were brought into production, an ongoing operation was completely modernized, and an environmental issue was appropriately remediated. The projects stretched over three continents, from arctic Russia to the Atacama Desert, from 16,000feet to sea level, from city suburbs to remote wilderness, from a low of $130 million to over $1 billion. Open pit and underground; mill and leach; gold, copper, molybdenum, and coal were all encompassed. The breadth of diversity experience from these projects inspired Cyprus Amax to create a “best practices” project management protocol, to steer corporate expansion into the next millenium. This paper summarizes those best practices, while high-lighting project management pitfalls to avoid.

Jan 1, 2000

By Albert Ruiz

South Coast Water District (District) operates the Beach Interceptor Sewer Tunnel (BIST) in South Laguna, Orange County, California between Mon-arch Beach and Aliso Beach (Figure 1). The 10,424-foot long BIST houses a 24-inch Techite gravity sewer pipeline critical to the District Sanitary Sewer Collection System that conveys 1 MGD of raw sewage to a wastewater treatment plant. The original tunnel was constructed in 1954 and the sewer line replaced in 1974. Periodic inspections by sewer pipeline maintenance crews have documented deterioration of specific intervals of the tunnel within the past few years (Sancon 2003). Rotting timber supports and rock falls in the tunnel as a result of the deterioration were endangering the sewer pipeline. A 50-foot section of the tunnel was determined to be in need of immediate repairs, which were carried out from January to August in 2007. This section was enlarged to a horseshoe shape and lined with shotcrete. The pipe was encased in concrete in the invert of the new enlarged cross section. Hatch Mott Mac-Donald (HMM) designed the emergency repairs, carried out an assessment of the rest of the tunnel alignment, and is currently developing a work plan for rehabilitating the entire tunnel.

Jan 1, 2008

By S. J. Benson

The Harts Range deposit, owned by Olympia Resources is located some 130 kms northeast of Alice Springs, in central Australia (part of Australia’s Northern Territory). The core economic minerals here are industrial grade garnet and alumino magnesio hornblende (AMH). The resource contains an estimated 2.3 million tonnes of recoverable garnet and 6.2 million tonnes of recoverable AMH, making Harts Range one of the most significant abrasive medium deposits in the world. Part of the general marketing axiom of Olympia Resources is to make high quality products from the garnet and also a special series of blended garnet/AMH products to match the needs for other sectors of industry. The deposit mineralization is of alluvial origin and thus, requires no significant liberation regimes. Over 50% of the head feed is in the form of SiO2/quartz and as much as 17% is –63micron clay slimes and mica. Original pilot scale testwork for flowsheet development centred around fairly conventional wet gravity systems, with spiral concentrators being the pre-eminent separating device. To a point, this type of flowsheet was going to achieve some of the aims albeit fairly predictably. The one area that this circuit would be very limited though is in the recovery of the very coarsest of the medium SG minerals. This was going to be a very important and longer-term costly flaw. Amongst the highest demand, greatest value of products to be produced will be the range of garnet & AMH in the +600 microns sector. A flowsheet dominated by spirals would be fated to forfeit a significant proportion of these coarse minerals to tails. At the Outokumpu Technology P/L test facilities in Perth, testwork was conducted using a pilot scale Floatex® Density Separator, the LPF-230 model. Using a twin stage approach, whereby a primary Floatex® underflow reports directly to a secondary Floatex®, recovery of the economically important +600 micron garnet was increased from 65% in the spirals-only flowsheet to 95% using the Floatex® based flowsheet. Finally, the other significant aspect of this approach is in substantial simplification of the circuit required and a huge reduction in plant footprint. Also, the nature of using hindered settling provides substantial opportunities for process control and automation.

Jan 1, 2005

Beneath some of New York?s most iconic buildings ? The Met Life Building, the Helmsley Building, the Waldorf Astoria ? crews are busily at work on the Metropolitan Transportation Authority?s long-awaited East Side Access (ESA) project. In fact, it is 14 floors beneath the famed Grand Central Station where one of the centerpieces of the project, the new Long Island Railroad (LIRR) station terminal, is being blasted and carved into shape. When completed in 2016, the $7.3-billion ESA project will increase LIRR?s capacity into Manhattan and significantly relieve congestion at Penn Station. Currently, 37 LIRR trains per rush hour roll into the crowded Penn Station where many riders must then transfer to subway trains to complete their commute. When completed, the ESA tunnels will bring an estimated 160,000 riders directly to Grand Central Station, saving those riders 30 to 40 minutes. Studies have found that more people work within walking distance of Grand Central than Penn Station. ?The benefits of the project are tremendous,? MTA Capital Construction President Michael Horodniceanu told more than 340 industry professionals attending the UCA of SME?s George A. Fox Conference in New York on Jan. 26. ?The ESA is the first expansion of the LIRR in 100 years. It will increase the East River tunnel capacity by 50 percent and will help support job growth around Grand Central.?

Jan 3, 2010