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By K. M. Atencio, T. Pike, S. Forrest

We will introduce the Small Business Liability Relief and Brownfields Revitalization Act, which is an amendment to CERCLA and the types of sites it includes and excludes, especially as related to mine-scarred land. We will also describe the types of available funds, whether they are competitive or not, what entities are eligible to receive them, and how to access them. We will introduce the legislation’s liability provisions; for example, the recently issued interim guidance clarifying some of the conditions that contiguous property owners, bona fide prospective purchasers, or innocent landowners must meet to qualify for the liability limitations provided in the Brownfields Law.

Jan 1, 2004

By T. Mudder, K. Harvey

The objectives for closure of a hard rock mine include minimizing long term environmental liability, attaining regulatory compliance, and maintaining geotechnical stability, while closing as cost-effectively as possible. Proper planning for closure should come during the feasibility study, design and permitting phases, and during operations as updates. The lack of a proper or updated closure plan can result in severe environmental and economic consequences. Effective mine closure is the result of a combination of innovative concepts, long-term commitments, and multi-party cooperation. The purpose of this paper is to discuss concepts, commitments, and cooperation as they relate to an effective closure plan.

Jan 1, 1999

By Henk van Muijen

To create a feasible plan to extract marine minerals there are a significant number of factors that must be analyzed. Most of these are known from conventional mining types. The following issues are the most relevant factors that have to be considered for mining a deep sea reserve economically: Sufficient reliable geological, physiographic data to create a proven reserve and mineral resources, Environmental Conditions, Geological & Geotechnical Study, Mining and ancillary equipment selection (design) and suitability, Environmental Conditions, Initial Transportation (seafloor to surface), Locations for stockpiling & processing, Processing, Power requirements, Land (Seafloor) ownership, Government, Economic Climate, Waste Handling, Methods of obtaining information and Post-Mining Activities.

Jan 1, 2008

By S. T. Krukowski

Traditionally the lime industry is governed by market, location, and transportation. These factors also may act as obstacles to global market access. Lime manufacture responds to market opportunities by first focusing on location. Lime markets are diverse and widespread, and ubiquitous occurrences of limestone make development of a widespread industry possible. Lime’s low to moderate unit value restricts transporting it long distances. Other factors (including lime reactivity, dedicated container use and other liabilities) limit shipping lime far. In the past many small to medium size companies made lime for local use. Today the global aspect of the industry is ownership by few large companies producing lime for local consumption.

Jan 1, 2003

By Karl Kuhnhenn

One substantial element of the NATM is to take into consideration the geotechnical rock behavior in the design of excavation and support methods. Even if this opinion is being shared increasingly, the stress analysis is not the sole criterion for a successful tunnel drive. By the beginning, the inventors of the NATM have clearly defined a number of principles which have kept their validity until now. The evaluation of different failure cases demonstrate how necessary the observance of these principles and their strict following during execution are besides the stress analysis. The great number of successfully excavated NATM tunnels are an impressive evidence for these principles.

Jan 1, 1995

By Dean J. Soderstrom

Soil and sands were contaminated with depleted uranium from weapons testing. This resulted in the formation of a complex mixture of uranium compounds. Characterization studies of the soil indicated the uranium was present as uranium metal, uranium oxides, silicon-bearing metallic uranium, and uranium silicates. A process was developed to selectively remove dense uranium compounds using gravity separation and a chemical extraction system to remove uranium which was not available for separation by gravity methods. Results from characterization studies and pilot scale testing are presented for background information. The primary purpose of this presentation is the report of the results achieved in the field application of the processes.

Jan 1, 1995

By C. J. Pritchard

Productivity improvements reduced the number of continuous miner sections from seven to three while maintaining full productive capacity. So a decision was made to test an advancing tailgate ventilation system on the shortwall mining section. Having the shortwall mine its own return air system has freed the third mining section for more productive, less costly mining. The advancing tailgate has provided effective ventilation across the face and gob with acceptable pressure losses. The low-productivity, tailgate-development, continuous-miner section has been transformed into to a high-productivity, development-retreat section that is also available for long-term mine development duties, increasing mine planning flexibility.

Jan 1, 1991

By Duport. P. J.

INTRODUCTION In February 1981, the Canadian Institute for Radiation Safety (CAIRS) initiated a routine Personal Alpha Dosimetry service for personnel of the Canadian uranium mining industry. This service is based on the use of the [Personal Alpha Dosimeter] developed by the French Atomic Energy Commission (CEA). The origins of personal alpha dosimetry and its rational are briefly described. Technical and organizational aspects of a routine personal alpha dosimetry service are outlined in this paper. HISTORICAL BACKGROUND International recommendations (1) and Canadian regulations have established Maximum Permissible Exposures (MPE) for each source of radiation exposure. Uranium workers in mines and mills are exposed to external radiation ( [y] rays) and to internal radiations ( [B] and [a] particles) which are delivered to the respiratory track by airborne alpha emitters (Rn and Th daughters and Long Lived Dust). To date, dosimetry for uranium workers has been performed by area monitoring/collective dosimetry. In North America the concentration of radon daughters is routinely measured by grab samples taken at the work place and by on-site gross alpha counting. The concentration of potential alpha energy is then calculated (usually by Kusnetz method) and expressed in Working Levels (WL). The time spent by each worker at a given work place is determined from his time sheets and used to calculate the individual monthly exposures to airborne alpha emitters, which is then expressed in Working Level Months (WLM). The uncertainties attached to such a procedure are obvious even in the case of frequent grab samplings and can be expected to lead to an underestimation of individual doses. Among fifteen possible sources identified in a mine situation, (2) four may stretch the standard deviation of the measurements' distribution, nine may lead to an underestimation and two may lead to either an underestimation or to an overestimation. To improve this situation, in 1971 the Atomic Energy Commission began studying the use of personal alpha dosimeters to determine individual exposures from the airborne alpha emitters encountered in the uranium industry environments. Criteria for a Personal Alpha Dosimeter In order to minimize the difficulties encountered in determining exposures received by uranium workers, the CEA in co-operation with the Atomic Energy Control Board of Canada (AECB), has developed a set of criteria for personal alpha dosimeters. Exposures may be determined easily and accurately using this criteria. Autonomy The dosimeter must operate for at least 10 to 12 hours. Excess time spent in the mine or in the facility may possibly be related to an accidental situation causing unusual levels of radioactivity. Since the dosimeter may be needed in non-underground settings where a cap lamp is not used, full autonomy is desirable. Maintenance, Periodicity of Reading In order to complement other dosimetry systems, the personal alpha dosimeter should be read monthly when the filter should also be changed. Routine air flow checks can be made according to local conditions (e.g. diesel loading). Radioisotopes Identification Since the exposure unit (WLM) is based on the concentration of potential alpha energy in the air, the personal alpha dosimeter should be capable of identifying each short lived alpha emitter included in the calculation of the WI, and WLM. Permanent Exposure Record Three points may be considered here: 1. In many countries, lung cancer in uranium workers is a compensable occupational disease. In some instances, compensation is awarded when it can be proven that the worker has received an exposure above a certain limit. The present uncertainty of the individual exposure makes the compensation procedure difficult. 2. By design, a personal alpha dosimeter must representatively sample all airborne particles, ranging in size from the unattached fraction to the upper limit of respirable aerosols (0.001 to 5 µm). The dosimeter must offer minimal resistance to the penetration of these aerosols. While the mining/ milling environment presents harsh conditions which may accidentally contaminate the dosimeter, it is important to be able to distinguish these cases of contamination and still obtain accurate readings. 3. A dependable dose register is most valuable for further epidimiological studies. The dependability of such a data base increases with the possibility of a second assessment of the dosimeters' reading (filter, film).

Jan 1, 1981

By James S. Browning

This article describes research conducted by the University of Alabama's Mineral Resources Institute on removing sulfur from coal using a combination of gravity concentration and flotation methods. The research used the gravity and centrifugal force capabilities of Humphrey's spiral to remove part of the pyritic sulfur and ash. Flotation of the Humphrey's spiral coal concentrate removed additional sulfur and ash. In addition to obtaining good recoveries of high quality coal, the tests demonstrated that pyrite in the wastes could be isolated as enriched flotation products by the combined gravity-flotation approach. Domestic coal production in 1980 reached a record 757 Mt (835 million st). Forecasts are that coal production and use will approach 907 Mt (1 billion st) by 1985, with much of the increased production being used for electrical generation. Of current production, it is estimated that about 454 Mt (500 million st) of coal nationwide are subjected to some degree of cleaning, ranging from crushing and screening to gravity concentration and flotation. With expanded coal production and more rigid controls placed on coal combustion, it is reasonable to assume that the tonnage subjected to some form of preparation will increase, with time, thereby adding to the burden of coal rejects being generated. A major problem associated with increased coal use for electricity generation is the need for utilities to conform to emerging federal air quality standards for sulfur oxide emissions from power plants. To a lesser extent, other industrial operations burning coal face a similar situation. Controlling sulfur oxide emissions by using low-sulfur coal or resorting to stack gas desulfurization are two recognized approaches, but removing sulfur from the coal, if possible, by physical beneficiation before combustion is preferred because of its simplicity and lower cost. Reducing the inorganic sulfur in coal to tolerable limits by physical beneficiation, including flotation, as now practiced, is still relatively inefficient and has not kept pace with the more sophisticated physical beneficiation approaches generally employed by the nonfuel minerals industry. As one phase of a broad program conducted by the Mineral Resources Institute at the University of Alabama on sampling and evaluating impounded fine size waste coal, tests were made using samples from two impoundments to determine the quality of coal recoverable by a combination of Humphrey's spiral concentration and flotation. Particular attention was given to organic and inorganic sulfur deportment and distribution in the various products. Another objective was to determine if pyrite in the waste could be recovered for possible marketing. The use of Humphrey's spirals to concentrate fine coal was practiced as early as 1947. At that time, the Hudson Coal Co. used spirals to concentrate anthracite fines. In 1950, spirals were used to treat fine-size bituminous coal and later, in 1976, spirals were reportedly used for removing pyrite from fine-size coal. More recent investigations have discussed the use of Humphrey's spirals for treating fine-size waste coal in Alabama. Samples Description Washer waste samples were obtained from two impoundments. One sample was representative of waste generated during washing steam coal from the American, Pratt, and Nickel plate seams in Alabama. The other sample represented metallurgical coal washer waste from processing coal from the Carter, Johnson, and Milldale seams. Partial samples analyses are shown in Table 1, and screen analyses of the samples are given in Tables 2 and 3. Screen ana¬lyses showed that one sample contained about 4% of material coarser than 2 mm (10 mesh) and the other contained about 13% of plus 2 mm (10 mesh) material. Also, the analyses indicated that ash and sulfur increased as the material's particle size decreased. Experimental Laboratory Tests Sink and float tests using a heavy liquid (1.4 specific gravity) were made on the different screen sizes shown in Tables 2 and 3 to determine the effectiveness of gravity concentration for separating coal from pyrite and other gangue constituents. Tests indicated that gravity separation, under optimum conditions, could be expected to yield coal products containing 10-12% ash, and 0.2-0.3% pyritic sulfur. Good coal recoveries could also be expected. Using sink-float tests as a guide, tests were made in a Humphrey's spiral by a procedure in which a 90-135 kg (200-300 lb) portion of the

Jan 8, 1982

By Stephen D. Hill, C. R. Ferguson, T. H. Jeffers, P. G. Bennett

The U.S. Bureau of Mines' Salt Lake City Research Center has developed porous polymeric beads containing immobilized non-living biological materials for extracting metal contaminants from waste waters. Immobilized biological materials include peat moss, algae, biological polymers, and other materials that demonstrate high affinities for heavy metals. The beads, designated as BIO-FIX beads, have distinct advantages over traditional methods of utilizing biological materials in that they have excellent handling characteristics and can be used in conventional processing equipment or low-maintenance systems. Toxic metals such as copper, cadmium, zinc, lead, and mercury are several of the many heavy metals effectively removed from mine waste waters using BIO-FIX beads, Continuous cyclic testing indicated that the beads continued to produce treated effluents which met National Drinking Water Standards (NOWS) after 150 loading-elution cycles. Adsorbed metals were removed from the beads using dilute mineral acids. In many cases, the extracted metals were further concentrated to enable processors to reclaim the metals, thus minimizing the generation of a hazardous sludge, Tests indicated that use of the beads in a low­maintenance system was particularly effective for treating remote acid mine drainage waters and small toxic seeps from hard-rock mining districts.

Jan 1, 1991

Dunn has written an excellent paper providing a wealth of advice on what is often the most costly consumable in the mineral processing plant. As he pointed out, grinding media selection and quality control can play a major role in successful plant operation. Owing to the economic importance of this topic, there are some important factors related to media sizing that I believe merit further comment. Dunn made reference to a slightly simplified version of the Azzaroni (1981) equation and pointed out its successful use for the Henderson SAG and Climax ball mills. Although both formulas are empirically based on successful plant experience, a notable discrepancy between them is that Bond has factored the work index by the ore specific gravity. This is invariably so, as the Bond work index is derived from the mass grindability (in grams per revolution) measured in a test mill with a fixed volume of solids load (Bond, 1961). A material having the same structural integrity but double the density of another will have double the grindability and just over half the work index. Thus, for the general case, specific gravity should be incorporated into any media sizing formulation that uses work index as the criterion for resistance to breakage.

Jan 1, 1990

By Gary D. Babbitt

Facing an orchestrated assault from the anti-mining lobby and its congressional allies, the Mining Law of 1872 may soon be either dramatically changed or even repealed. In 1989, Sen. Dale Bumpers (D-AK) introduced Senate Bill 1126 entitled the "Mining Law of 1989." It has been through several hearings and is still in the Senate Committee on Energy and Natural Resources, where Sen. Bumpers is the number two ranking Democrat. In the House, Rep. Nick J. Rahall (D-WV) introduced the "Mineral Development and Exploration Act of 1990," HR 3866. This bill is in the House Committee on Interior and Insu¬lar Affairs. (The numbers on these bills, and perhaps some of their language, will be changed when they are reintroduced in early 1991. However, their substance is expected to remain substantially unchanged. Bill numbers here refer to legislation as it was numbered in the 1990 Congress.) In the eyes of its supporters, Bumpers' S 1126 appears to be more complete and has the inside track over the Rahall bill. Bumpers' bill includes provisions for royalties, bonding and reclamation. The Rahall bill is criticized by opponents of the Mining Law for its failure to include a royalty provision and for not having specific bonding and reclamation provisions.

Jan 1, 1991

By Raymond E. Krauss

The McLaughlin Mine is based on a world class epithermal gold deposit located in the coastal thrust fault of northern California, about 1 12 air km (70 air miles) north of San Francisco. Owned and operated by Homestake Mining Co., the McLaughlin deposit contains about 18 Mt (20 million st) of gold ore at an average grade of 5.2 g/t (0.152 oz per st), or about 93 t (3 million oz). The area was identified as a gold target by Homestake in early 1978. Drilling confirmed it to be a commercial deposit by 1980. The mine was then planned, engineered, built and brought into production by March of 1985. The deposit was historically a part of the Knoxville District. It was mined for cinnabar, which was used to produce mercury for use in recovering gold and silver in the Mother Lode and Comstock districts. At that time, the mine was called the Manhatten and later the One Shot Mine. It was worked for more than 100 years, producing about 76,000 flasks of mercury without any awareness of the presence of economic concentrations of gold. By 1978, the site was largely disturbed and entirely unreclaimed.

Jan 1, 1990

Equity investments and loans are made in oil and gas and mining projects by the World Bank Group (WBG) as one piece of a multi-faceted quest to reduce poverty. The Bank mandate to reduce poverty through private sector investments has been contested by civil society organizations, so the Bank has established an independent review, entitled the Extractive Industries Review (EIR) www.eireview.org. The EIR is reviewing, from the perspective of affected stakeholders, the impacts and benefits of WBG development policy. In this paper, we review the indicators used by the WBG, academics and others to measure the effectiveness of investments. We argue that currently used frameworks and indicators do not capture local or regional data sets, and instead focus on available and easily aggregated information at the national level. A case review of the WBG?s International Finance Corporation (IFC) and Multilateral Insurance Guarantee Agency (MIGA) investments and loans in Sub-Saharan Africa provide material data buttressing the argument. Poverty studies in the extractive industries have a long way to go toward measuring and accounting for dollars spent and invested. The paper concludes with a call for project level and regional indicators to track poverty alleviation. Data gathered for this research was funded in part by the Extractive Industries Review.

Jan 1, 2003

By Steven R. Wardwell, Gerald G. Stokes

INTRODUCTION A compaction grouting program to control ground loss, and to minimize surface settlement, was developed for the West Tunnel of the Phoenix Storm Drain Tunnels. The West Tunnel was 4,200 m long, 7.56 m in excavated diameter, and was excavated with shallow cover through the central Phoenix business district. The tunnel could not have been successfully excavated without the compaction grouting program. HISTORY After heated political debate over a ten year period, the Arizona Department of Transportation (ADOT) was granted approval to build the Papago Freeway, an extension of Interstate 10, through central Phoenix. To comply with environmental constraints, a portion of the Freeway was depressed, requiring an excavation 10 meters in depth, thus intersecting surface run-off from the northern section of Phoenix. This required that ADOT and Project Design Consultant, Howard, Needles, Tammen & Bergendoff (HNTB) design a drain system to collect run-off and transport it approximately 4 kilometers to the Salt River through the City of Phoenix. Tunnels were chosen for the main discharge conduits because depth and location of the system made cut and cover construction impractical. A contract for construction of the tunnels was awarded to Shank-Artukovich-Ohbayashi (S-A-O) on May 24, 1984.

Jan 1, 1987

By Barry J. Hansen

Mining can make two major contributions to the cleanup of the environment. The first of these is the extractive technology that has become highly developed as a result of centuries of development. Of equal impor­tance are the methodology of analysis and the development of engineering solutions that are the stock in trade of the mining industry. Despite the differences between the industries, the processes for the development of a mine and the cleanup of a hazardous waste site are similar. The characteristics that impact the ability to develop a suitable process for treating an ore body or correct­ing an environmental problem are those relat­ed to the distribution of the contaminant or metal in the host material.

Jan 1, 1991

By Thomas M. Goodell, Timothy D. Arnold

Dilute-phase pneumatic conveying has been used in the mining industry since the 1920s. It has primarily been used for the hoisting of coal and salt ores, and as a transportation medium for backfill material. More recently there have been investigations into a wider variety of applications, which this paper addreses. The paper will point out some deficiencies in the system. It 1s not the "champion" of the mining industry, but rather an excellent srste?1 with a variety of applications that may not have been studied m enough detail. The most imaginative applications to the Redpath Pneumatic Conveying System have been initiated by persons needing an innovative application to a specific predicament.

Jan 1, 1992

By Bob Snashall

Mines, miners and mining figured in the revolutionary birth of the USA. This occurred with a little help from General Washington's friends, the French. When the colonial minutemen confronted King George's "bloody lobsterbacks" at Concord, MA, in April 1775, the resulting "shot heard around the world" resounded in Versailles. France was sympathetic to the patriot's struggle. Before the Lafayettes shipped out, came French muskets and powder... but not many musket balls. The Continental Congress issued orders to get the colonial lead out for shot and shell. Colonial mining enterprises had been chiefly local affairs, cheaply supplying product to the surrounding communities. Since wood was accessible for fuel, coal had not been exploited.

Jan 1, 1990

By T. S. Golosinski

Timely and efficient conversion from traditional to sustainable development of mineral resources requires that managers, engineers and other mineral industry professionals become familiar with the related techniques and methods. To fill this need the online Master of Engineering program has been developed at University of Missouri-Rolla. Designed primarily for mature students with an engineering or science background this program allows for specialization in several areas of sustainable development of earth resources. To accommodate mineral industry professionals working in remote locations all courses constituting the program can be taken online, without the need to attend the classes in person. The paper describes the program and discusses the experience gained during the first two years of program offering.

Jan 1, 2003

By David L. Moffatt, Leon Peters

A unique electromagnetic pulse sounding system for the detection and identification of geological and man-made anomalies which represent hazards in hard rock rapid tunneling operations is described. The main features of the system including a periodic video-type pulse interrogating signal and a probe structure that permits operational modes which either "see" or are "blind" to homogeneous-type targets are reviewed. The results of experimental pulse measurements on targets buried in the overburden and in a limestone medium are presented. Since the electrical properties of limestone are not radically different from those of a hard rock medium, conclusions based on these data should be valid for a hard rock media also.

Jan 1, 1997