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By Michael Horn

[An economic trading region made up of 22 eastern Washington, northern Idaho, and western Montana counties, with Spokane, Washington as the central place, was defined for this study. modeling system with the, 1985 county database was to create an Input/Output based model of the regional economy. The leading ice, with respect to income, employment, value of exports, and total industry output are shown for each county and the region. The value of total industry output from natural resource based industries is also shown for each county and the region. Interindustry transactions, final demand, and value added components for the region are shown in the Regional Gross Flows Table. The total gross output for the region is valued at $36.7 billion. Total industry output for the region is $18.1 billion. The region provides $5.4 billion in income to a work force of 286,000. Spokane County, Washington accounts for about 50 percent of the regional total industry output, income, and employment. Both Spokane County and then as a whole produce about 80 percent of the total industry output for final demand with remaining 20 percent going to intermediate inputs for further production. Spokane County exports about 43 percent of its total output while 35 of the regional output is exported. Exports account for more 50 percent of the total in 18 of the 22 counties within the region. About 9 percent of the total industry output from Spokane County and 19 of the total output from resource f: .t *III For counties Spokane a industry ? N from nafural resource based represents 18 percent ?.{1 to 71 s. ?-{ and averages 39 r. ?-11 of total county +' ' 7:. FS.-f.?) If t. Natural resource it us -t for more than 50 coutny 1 s ? sass in seven counties within region.]

Jan 1, 1992

By Mark S. Sanders

This report presents recommended visibility requirements for continuous miner, shuttle car and scoop operations and details the methodology used to generate them. A task analytic approach was used to define information requirements and visual features which served as sources of information. Information requirements were prioritized and the location of visual features determined. From this analysis, visual attention locations, containing one or more important visual features, were identified. A total of 71 locations-were identified for continuous miners, 54 for shuttle-cars and 54 for scoops. A procedure was developed for assessing whether operators in existing machines could be expected to see the visual attention locations. The procedure makes use of a Human Eye Reference Measurement Instrument (HERMI) designed for this project and an outside-in photographic procedure for documenting compliance with the recommendations. A sample of continuous miners, shuttle cars, and scoops were used to test the procedure. Results are presented in the report.

Jan 1, 1981

By Paul M. Price

The Mouat mine, Nye, Mont., was reopened in 1953 by the American Chrome Co. under a Defense Minerals Production Administration contract. Operations were terminated in 1961 after completion of the contract. Mining methods employed during this period are described in detail, and cost data are presented by years for 1953 through 1959. Ultramafic rocks of the Stillwater complex in Montana contain the largest domestic resource of chromite, and the Mouat mine has been the largest producer. Mine reserves were estimated in 1960 to be about 4.4 million tons containing 22.5 percent Cr203. The chromite deposits occur as a series of overlapping bands or lenses roughly paralleling the steeply dipping layers of the complex. Only two of the chromite layers have proven to be of economic importance. One layer is 2 to 1.6 feet wide; the other is 3 to 8 feet wide. Shrinkage stoping was generally used throughout the mine, but various methods of ore breaking, scope drawing, chute construction, etc., were tested to improve output and lower costs. Long-hole stoping proved to have limited use. Breasting down benches, developed outward from the center of the stope with air-leg drills, was satisfactory only in wider scopes. At the close of operations, the company had standardized the use of lightweight stopers to advance a flat back by breaking from a centrally located face. Mining costs were reduced 47 percent during 7 years of operation.

Jan 1, 1963

By Thys B. Johnson

The mine system analysis and evaluation study presented in this report was part of the U. S. Bureau of Nines' Tertiary channel project conducted under the Heavy Metals program. The Badger Hill pit, located on the west end of the San Juan Ridge area, near Nevada City, California, was the site of the Bureau's field work. The objectives of this study were: (1) Determine potential alternative mining systems for some of the large tertiary channel gold-bearing gravel deposits, and (2) Identify areas of technology where further investigation would be merited because of their potential inclusion in a mining system for such deposits, The study involved the development of a mineralized block inventory, an economic block inventory, determination of optimum ultimate mining limits and a preliminary economic mining system evaluation. Computer programs were developed and utilized for each of the study phases stated above. The sampling program conducted at Badger Hill by the Bureau Delineation Group together with confidential drill hole data provided by the San Juan Gold Co. formed the basic gold values and distribution information from which a deposit model was developed. The deposit was divided into minable block units and net economic values were assigned to each block for various configurations of both open-pit and underground mining methods based on cost and performance data provided by the various Bureau of Mines Research Centers. A number of controllable variables such as: (1) Mining method (open-pit and underground), (2) depth of mining cut, (3) production rate and (4) equipment type and capacity were evaluated. The prime measures of effectiveness on which the mining systems where judged were discounted cash flow rate of return and maximum utilization of natural resources. The analysis showed that underground mining of the Six-Mile Tertiary channel gold-bearing gravel deposit under consideration was uneconomical and did not permit maximum recovery of the resources within the channel. It was also apparent that mining the Six-Mile Deposit for gold alone is uneconomical or at best marginal at a gold price less than $80 per ounce. The analysis showed that the potential for an economic mining operation within the Six-Mile Deposit exists when the gravel resources of the channel are considered together with the gold. It was determined that the highest rate of return would be realized with a 20-year open-pit mining operation yielding 745,000 ounces of -gold and 55 million cubic yards of usable gravel.

Jan 1, 2012

By Ned Baker

Details are given of a Hydride Fuel System to provide 5 kg of HZ to fuel a Caterpillar 3304 engine previously modified to operate on hydrogen fuel and intended to power an underground mining vehicle. The Fuel System was installed onto the engine and the Engine/Fuel System tested under cold start conditions and a full range of engine loads and speeds. Refueling tests were also performed. The fuel system tested will support full engine power and allow delivery of at least 3/4-power on a continuous basis, from cold start conditions.

Jan 1, 1983

Reports by researchers in government, industry, and universities of the United States are given for various projects on basic coal research concerning, the metamorphism, physical and chemical properties, and reactions of coal, and how many of these studies can lead to better utilization of coal.

Jan 1, 1968

By Wojciech Klecan

Cobb County, located on the northwest side of Atlanta, GA, is continually growing and, like many other metropolitan areas, it needs to increase the capacity of its waste water system to meet future demand. The Cobb County Water System (CCWS) is the responsible agency for water distribution, waste water collection and treatment in most areas of the county. CCWS, one of the most progressive agencies in the metro-Atlanta area, is addressing its future waste water capacity needs in the southern part of the county with the construction of the South Cobb Tunnel and Pump Station. This project consists of an 8.8-km- (5.5-mile-) long, 8.2-m- (27-ft-) diameter, tunnel boring machine (TBM) excavated waste water storage and conveyance tunnel; six tangential vortex-flow intakes ranging from 1,533 to 5,700 L/s (35 to 130 mgd) peak flow capacity, two construction shafts, six 1.8-m (6-ft) finished diameter connecting tunnels ranging in length from 6 to 975 m (20 to 3,200 ft) and a 5,700-L/s (130-mgd) wet/dry pit pump station. The pump station will have a semi-circular wet well with a dividing wall that extends almost to the top of the shaft and a spilt dry well for reliable operation. Roller gates will control the flow to the wet well from the tunnel. The pump station will have six 1,420 L/s (32.5 mgd) pumps and two sets of stair wells and elevators. With a finished diameter of 32 m (104 ft) and a depth of 62 m (204 ft), this is the largest pump station shaft constructed so far in Georgia for the dewatering of a waste water tunnel. The pump station shaft was also the highlight of the well attended and successful 2009 Shaft Design and Construction Short Course held in Atlanta, Sept. 10-11. The two-day course was sponsored by the Underground Construction Association of SME and Pennsylvania State University and concluded with a field trip to the pump station shaft. The tunnel starts south of the city of Austell and finishes at the South Cobb Water Reclamation Facility (WRF), located on the banks of the [ ] Chattahoochee River just north of Interstate 20 (Fig. 1). The South Cobb Tunnel will run 30 to 137 m (100 to 450 ft) below the surface, with an average depth of about 91 m (300 ft), through metamorphic rocks (Fig 2). The construction contract was awarded to Shea-Traylor JV with the lowest bid price of $305 million and notice-to-proceed was given on July 14, 2008. Jordan Jones & Goulding, Inc. (JJG) is the project designer and performed the geotechnical investigations. Parsons/Jacobs Associates is the construction manager. The South Cobb Tunnel is CCWS?s second deep hard rock tunnel. The 15.3-km- (9.5-mile-) long, 5.5-m- (18-ft-) diameter TBM excavated the Chattahoochee Tunnel was the first deep tunnel to be construced in Cobb County. Construction began in 2000 and the project was completed four years later. It is located about 16 km (10 miles) northeast of the South Cobb Tunnel in similar geology. It was designed by JJG to meet east Cobb?s long-term waste water capacity needs and provide flow equalization to the R.L. Sutton WRF. The Chattahoochee Tunnel was named ?Outstanding Civil Engineering Project of the Year? by the Georgia Sec-tion of the American Society of Civil Engineers in 2006.

Jan 1, 2009

By Lisa A. McDonald

The environmental compliance process affects all aspects of hardrock-mining operations, from exploration through post-closure. The primary components of the environmental compliance process are requirements under the National Environmental Protection Act of 1969 (NEPA) and the permitting requirements associated with various other federal, state and local laws. This study considers the Greens Creek Mine and the development of two other projects (Alaska-Juneau & Kensington). These mines were used as the foundation for a case study of the impacts of the environmental compliance process on hardrock-mining activity in Southeast Alaska. The case study presents the institutional and legal requirements, followed by a discussion of the impact of this process on the production and timing of the three mines. The results of this preliminary study reveal some interesting findings, some expected and others unexpected, regarding the impact of the permitting process on the exploration, development and (proposed) operation of the three mining projects in the Juneau area. Determining the cost of compliance with these requirements is an important step in evaluating the appropriate course of action to protecting the environment while providing the necessary raw materials needed for society. This preliminary study highlights the initial starting point for such an analysis.

Jan 1, 1992

By Barry Olson

The Peñasquito deposit in Mexico is one of the largest grassroots precious metal discoveries to be developed in recent years. Goldcorp Inc. acquired the gold-silver-lead-zinc property with the acquisition of Glamis in 2006. The company has since committed US$1.5 billion to construct the mine, mill and associated facilities. The first of two 50-kt/d (55,000-stpd) mill and flotation lines is currently being commissioned while engineering and construction continues on the second line. A high-pressure grinding roll (HPGR) will ultimately take total throughput to 130 kt/d (142,000 stpd). The Peñasquito property is located in the northeast corner of Zacatecas state, Mexico. The elevation of the property averages 1,900 m (6,200 ft) above sea level and it is situated in a wide east-west valley. Except for one small outcrop (Peñasquito), the area is covered by up to 30 m (98 ft) of alluvium.

Jan 1, 2009

By Gregory T. Ziegler

A complex soil profile and high water table, together with a below-grade active subway tunnel, an above-ground elevated railway line, and the heavily travelled Northern Boulevard all passing above the tunnel alignment, combined to make mining of New York?s Northern Boulevard Crossing what is widely considered to be the most challenging portion of the multi-billion-dollar East Side Access project. The Northern Boulevard Crossing is a vital link in this project which, when completed, will connect the Long Island Railroad to Grand Central Terminal in Manhattan. How the sequential excavation method (SEM) tunneling was successfully accomplished, despite the obstacles, was a textbook exercise in practical innovation coupled with close cooperation between the owner, the construction manager, Hatch Mott MacDonald, the designer, Parsons Brinckerhoff, the contractor, Schiavone-Kiewit, and spe-cialty geotechnical contractor, Moretrench.

Sep 1, 2013

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half being metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is intended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1976

From Sept. 22-24, the Las Vegas Convention Center will be home to MinExpo 2008, the world?s largest mining equipment show that comes along once every four years. Sponsored by the National Mining Association (NMA), this year?s show is on pace to be the largest ever. Nearly 1,300 exhibitors have purchased nearly 55,700 hm2 (600,000 sq ft) of booth space. At the center of it all will be some of the most impressive mining equipment that the industry has to offer. And in the shadows of the massive haul trucks, drill rigs and bulldozers, attendees will be able to see the latest and greatest products including hand tools; the latest in automation and robotics; safety and communications equipment; longwall mining equipment; engines and parts; materials handling and processing equipment and services; pollution control equipment; reclamation equipment and services; computer applications; consulting and financial services and more. While many companies will be on hand to display the tried and true, there will also be plenty of new things to see. ?We anticipate that a whole range of new products will be introduced at the show,? the NMA said of the show that has been called the world?s richest deposit of mining technology, services and products. In addition to the show that will take place in Center Hall and North Hall of the Las Vegas Convention Center, MinExpo 2008 includes a conference program with 20 educational sessions that will tackle the most timely and pressing issues affecting the mining industry. Many of the industry?s top professionals will lead the discussions.

Jan 1, 2008

By Wilbert J. Huff

This is the sixth of a series of annual reports describing the work of the Explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with the activities of the division from July 1, 1940 to June 30, 1941. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders, to whom specific credit is given.

Jan 1, 1942

By R. W. Barnes

This circular presents results of a survey conducted by the Bureau of Mines to ascertain the extent to which dust-control practices are employed in the coal-mining industry. This survey was initiated because of increasing realization of the possible harmful effects of the inhalation of dust upon the health of coal-mine workers and the advent, during recent years, of new types of mining machinery and new mining methods that may have a direct effect upon the extent of exposure to airborne dust experienced by persons mining coal. Anthracite Mines The survey covered 169 anthracite mines that were operating from November 1, 1953, to July 1, 1954. It showed that large mines employing more than 100 men were doing most to control dust produced during mining.

Jan 1, 1956

By Wilbert J. Huff

This is the sixth of a series of annual reports describing the work of the? Explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with the activities of the division from July 1, 1940, to June 30, 1941. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders, to whom specific credit is given.

Jan 1, 1942

By Laura McNally

In 2006, McNally International Inc., in a joint venture partner-ship with Aecon Constructors, was the successful bidder on two York Region Tunnel Projects: the Bathurst Collector/Langstaff Trunk Sewers and the York Durham Sewer System (YDSS) Interceptor Sewer 19th Avenue, both in the Toronto area. These projects comprised a total of 13 km (8 miles) of 2.74 m (9 ft) finished diameter tunnels and are both part of the YDSS. Both contracts required the use of earth pressure balance (EPB) tunnel boring machines (TBM) with a precast concrete segmental liner.

Jan 1, 2008

By I. L. Bell

The ironmasters of America had asked the Iron and Steel Institute to visit the USA. The Council decided it was not possible to accept, but Mr. Bell visited; this is an account of his trip. Topics covered include transport, charcoal, coal measures, coal, anthracite, bituminous coal, flux, magnetic iron ore, specular iron ore, limonite, red hematite, clay ironstone, black band ironstone, smelting works, blast furnaces of Pennsylvania, Lake Champlain furnaces, Lake Superior furnaces, Cleveland furnaces, Pittsburg furnaces, Missouri furnaces, and those of the southern states. He goes on to describe Catalan hearths, malleable iron works, Bessemer works, the Blair steel process, and labour.

Jan 12, 1875

By Eldon C. Pattee

Reconnaisance samples of reported beryllium occurrences in Idaho, Washington, Montana, and Oregon were chemically and spectroscopically tested in a mobile laboratory. The two predominant types of occurrences were green beryl associated with Cretaceous intrusions and disseminated aquamarine associated with Tertiary intrusions. Although the beryllium content of known deposits in the Northwest is too low for economic development at present, total submarginal-grade beryllium resources in pegmatites are estimated to be 570,000 to 1,870,000 tons containing 0.024 to 0.167 BeO. A potential source of 500,000 to 700,000 tons of beryllium-bearing tactite in Idaho and Montana averages 0.033 to 0.080 percent BeO.

Jan 1, 1968

This report is the 24th in a series summarizing research on coal and related investigations3 by the Bureau of Mines. The coal programs of the Bureau of Mines include a wide range of theoretical and applied studies--such as fundamental studies of coal structure and properties, the development and evaluation of new mining techniques, and work toward more effective processing and utilization of coal. The scope of these programs is indicated, in topical outline, by the table of contents. These investigations are integrated into a broad but coordinated effort to develop information on coal that will benefit the coal mining industry and the coal consumer while promoting the wise conservation and utilization of our national coal resources. Any attempt to summarize in one volume the progress in all of the program areas indicated must necessarily be limited to a brief review of developments, without detailed reporting of the data. However, while the brief discussion in each section will present only the highlights of the Bureau's work during the year, details of many of the operations or investigations described here can be found in the publications cited throughout the text. Other work, reported here for the first time, will be covered in greater detail in later publications.

Jan 1, 1962

By M. Kanefsky

Two channel polarity coincidence and polarity difference statistics are analyzed. The signal, common to both channels, consists of sinusoidal bursts where the exact frequency of the signal is nearly known, but other parameters such as amplitude, phase, and pulse starting time are unknown. The noise inputs are dependent, narrow band, Markov processes. It is shown that the performance depends not only on the signal uncertainties, but on the precise shape of the cross-correlation functions between the noise in-puts. By using two polairty difference statistics in addition to the polarity coincidence statistic, it is shown that the decrease in performance, as well as the cost of hard limiting due to correlated inputs, can be made small.

Jan 1, 1981