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By Gail L. Achterman

Most mining companies today perform site assessments and operational or compliance audits regularly. The purpose of these audits is to review company facilities and operations to determine whether they comply with applicable federal, state and local environmental laws and regulations. Why Audit? Companies adopt assessment and audit programs for legal and business reasons. The business reasons include: (1) ensuring efficient and cost-effective compliance through early problem identification and resolution; (2) planning and implementing business transactions such as real estate conveyances, loans, mergers and acquisitions, and waste disposal service contracts; and (3) employee training and relations. Legal reasons for audits include: (1) avoiding enforcement actions and penalties; (2) meeting environmental permit certification requirements; (3) avoiding corporate officer liability; and (4) meeting Security and Exchange Commission disclosure requirements. The Environmental Protection Agency ("EPA") encourages environmental auditing by regulated entities. The EPA Environmental Auditing Policy Statement was published in the Federal Register on July 9, 1986 (51 Fed Reg 25,004). Although the existence of an auditing program does not create a defense to or otherwise limit a company's regulatory responsibilities, EPA considers compliance programs in setting inspection and enforcement priorities. If a company makes an honest effort to identify and correct its own problems, EPA's enforcement approach is influenced, especially if violations are promptly reported. Perhaps more significant to many executives, the U.S. Department of Justice issued guidelines last year on when it will pursue criminal prosecution for environmental violations. See Department of Justice, "Factors and Decisions on Criminal Prosecutions for Environmental Violations in the Context of Significant Voluntary Compliance or Disclosure Efforts by the Violator," (July 1, 1991). It is now commonplace to read about major companies pleading guilty to criminal violations and paying millions of dollars in penalties. For example ALCOA recently agreed to pay criminal fines and civil penalties totaling $7.5 million for unauthorized excavation of PCB-contaminated soil and improper dumping of spent caustic solution. No executive wants to explain to the Board of Directors or shareholders why the company was criminally indicted. The Department of Justice considers factors such as voluntary disclosure, preventive measures and compliance programs, such as a regular compliance auditing program, the effectiveness of the disciplinary system for employees who violate the company's environmental policies, and subsequent compliance efforts by companies to remedy ongoing noncompliance. The Department of Justice looks closely at whether audit recommendations were implemented in a timely way and whether environmental compliance was a standard by which employees were judged. The Lawyer's Role. The role of the lawyer in an audit team deserves special attention. When enforcement action or litigation has begun or is contemplated or a government agency has asked for information, attorneys always should be directly involved in environmental audits. In most situations, however, environmental audits are management tools, and the attorney's role should be to advise the team. The attorney can help make sure the team understands the laws and regulations the facility must

Jan 1, 1992

By J. Noll, E. Cauda, T. Barone, S. Vanderslice

Measuring diesel particulate matter (DPM) for underground metal/nonmetal mine compliance samples is done by collecting DPM onto quartz fiber filters and analyzing the samples via NIOSH method 5040 for elemental carbon (EC) and total carbon (TC). As part of the sampling train, two quartz fiber filters in tandem are housed inside an SKC DPM cassette that includes an impactor. The impactor segregates DPM and mine dust, and the second filter is used to correct for adsorption of vapor phase organic carbon (OC). Since the value of the second filter is subtracted from the first, the pre-existing carbon on the filter media for both filters needs to be comparable. In addition, the pre-existing carbon on the media should be low for accurate and sensitive results. However, there have been some reports of elevated OC on the filter media of the SKC DPM cassettes, which would cause the limit of detection (LOD) to be higher than reported at times. In this study, blank SKC DPM cassettes from different batches and with different expiration dates were analyzed to quantify the amount of carbon on the filter media and to determine the LOD and limit of quantification (LOQ) associated with these samplers. It was found that the organic carbon and total carbon on the media was about five times higher than quartz media used in samplers from other studies. The average TC on the blanks was 2.57 μg/cm2 with a standard deviation of 0.70, resulting in a LOD of 21 μg/m3 TC, 8-hr Time Weighted Average (TWA), and LOQ of 69 μg/m3 TC, 8-hr TWA, when using these samplers for collecting DPM. The LOD and LOQ may be improved through some sample preparation techniques. INTRODUCTION Exposure to diesel exhaust (DE) is associated with an increased risk for lung cancer and other adverse health effects (Attfield et al. 2012, Silverman et al. 2012, Ping and Guang 2017, IARC 2012). Pronk et al. 2009 reported that the highest exposed groups to elemental carbon (EC) from DE worked in underground sites in mining and construction and they were exposed to concentrations between 27–658 μg/m3. At concentrations (1–25 μg/m3 EC) well below those observed in mining, diesel particulate matter (DPM) exposures were estimated to increase the risk of cancer by levels exceeding those typically acceptable for occupational risk in the United States and Europe (Vermeulen et al. 2014). This suggests that underground miners are especially at risk because of their more substantial exposures in confined working spaces. As a protective measure, in 2001, the Mine Safety and Health Administration (MSHA) promulgated a rule to limit exposures of metal/nonmetal underground miners to DPM to an 8-hr time-weighted average (TWA) of 160 μg/m3 total carbon (TC) (MSHA 2001, 2006).

Jan 1, 2019

By Sadatoshi Ohmori, Simin Zhai, Devini Abeyawardena

A road tunnel is planned to be constructed in soft, high overburden ground of around 600 m in Japan by using the center drift advancing method. The dodging effect and early ring closure of the center drift were expected to reduce the displacement and deformation of tunnel and promote safe construction. The measurement result during construction was analyzed and those effects, which the displacement and deformation after the widening excavation decreased and its effect increased as the center drift radius increased, were confirmed by numerical analysis. Also, the effect of the early closure of center drift after widening excavation did not have much effect.

Jun 23, 2024

By Samuel S. M. Chan

Rock surrounding mine openings frequently is an impermeable type such as shale or granite. Most rock, however, has joints, bedding planes, cleavage planes, or other potential discontinuities. Permeability to fluids (gas or liquid) may exist via natural joints or fractures in an otherwise impermeable rock. In the mining situation, tectonic and induced tensile and shear stresses may be great enough to cause joints to open or fractures to develop in previously solid rock. The rock, as a result, becomes less self-supporting and may - require artificial support such as rock bolts or timber. Simultaneously, as fractures develop, permeable paths may be created. If fluid can be injected into a previously solid and impermeable rock mass, a logical conclusion is that a fracture (crack) flow path must be transmitting that fluid. The U.S. Bureau of Mines Laramie (Wyo) Energy Research Center has been evaluating results of in-situ oil shale fracturing (hydraulic or explosive) and retorting experiments by. a fluid (air) injection , and borehole air flow profile logging technique since 1956 (1, 14, 15). In the oil shale case, it is imperative to know the location and flow capacity (permeability) of natural fractures, if they exist, and induced fractures that inter-connect vertical wellbores at depths of fifty to several hundred feet. By injecting air into one wellbore in a system of several wells and measuring input volume and pressure while simultaneously measuring the output of other wellbores, the minimum areal extent of interconnecting permeable fractures can be determined. Exact locations (depths) of fractures and individual fracture flow capacities between wellbores can be determined by air flow profile logging (14, 15). Knowledge of fracture locations and permeability is essential to rational experimental in-situ retorting design.

Jan 1, 1973

By Erica Frederickson

"Millennials. Doesn’t the word just make your blood boil? You’ve probably encountered one of those kids who think they know best despite a lack of any real experience.Hi, my name is Erica, and I am a Millennial. We often get a bad rap, sometimes for good reason. But we do have qualities that are often overlooked. For example, I am happy to share with my generation a real desire to make a difference in the world and a commitment to innovation. Does this mean I think we always have good ideas? No – especially not right away. After all, few of us came anywhere near a piece of construction equipment until arriving for our first job, as was the case for me. We may have fancy degrees, but not many of us learned to run a jackleg drill in school.Two weeks after graduating college in 2011, I packed up my bags and moved to New York City to work as a field engineer for Traylor Bros. Inc. on the Queens Bored Tunnels project (Granite/Traylor /Frontier Kemper, JV), part of NYC MTA’s multi-billion dollar Long Island Railroad East Side Access project. It was here I became acquainted with the notorious New York City union workers. Perhaps the greatest challenge of my career thus far was earning the respect of the field supervision and craft workers on this first project.The first time I asked a maintenance mechanic to clean a piece of equipment in accordance with our maintenance protocol I got a flat-out “No.” It was the most powerless I had ever felt. But why should these experienced workers trust a 21-year-old girl with her civil engineering degree and no prior experience? I realized no employee on the job had any reason to listen to me — not until I proved my worth. Fortunately, I arrived on the job site just as we were commissioning the slurry plant for the first tunnel drive. I dove into learning as much about the slurry tunneling process as possible and was able to quickly pick up the ins and outs of running the slurry separation plant. As none of the other engineers or management had first-hand experience on a slurry tunneling job, I soon became the go-to engineer in the slurry plant. No one questioned me if I asked to have something done around the plant after that, or if they did, they quickly learned that I had a convincing answer as to the need for the task. I was even able to play a large role in shaping our slurry monitoring and control methodology."

Jan 1, 2015

By B. Holen, J. R. Baregi, J. A. Organiscak, A. B. Cecala

The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company’s Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system’s effectiveness in controlling airborne dusts and particulates. The booth’s dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-µm respirable size particulates under various HVAC airflow operating conditions.

Jan 1, 2015

By Dan Nilsson

INTRODUCTION There are many mine planning factors in sublevel caving, as in the other mining systems, which when varied can substantially alter mining costs and profit¬ability. In this chapter, the following four topics are addressed with regard to economic optimization of sub¬level caving: production planning, haulage level spacing, orepass spacing, and extraction cutoff. The costs used here are the right order of magnitude but since each mine is unique, they should be considered only as examples. The objective is to demonstrate the tech¬niques which can be used. In a real mine, the evalua¬tions must be done using actual costs and conditions. It is difficult to predict exactly the costs involved, and therefore it is valuable to perform a sensitivity analysis to evaluate the effect of making incorrect as¬sumptions. Since the mining industry is very capital intensive, the effect of the interest rate must also be studied. PRODUCTION PLAN FOR AN IRON ORE DEPOSIT Introduction The first and most important thing to do before de¬signing an underground mine is to establish a long-range production plan. Such a plan is necessary for all eco¬nomic evaluations and should provide information about the lifetime of the mine, how much ore and waste must be handled per year, how much development per year is required, etc. An example is given in the following section. Problem In an iron ore mine sublevel caving is used. The iron content is 42%, and the mine supplies a pelletizing plant with an annual capacity of 3 million t/a. The ore body is shown in Fig. 1. The length of the ore body is 1000 m and the width is 100 m. Each slice is 10 m high, and there are 10 m be¬tween crosscuts, each of which has an area of 20 m2. The density of the ore is 3.5 t/m3. The spacing between rings is 2 m, and the extraction is 100%. The iron con¬tent is 66% in the pellets and 6% in the tailings. The problem is to develop a detailed production plan. A typical sublevel caving sequence is shown in Fig. 2. Solution Amount of ore per meter of crosscut: 20 X 3.5 = 70 t. Number of crosscuts per slice= 100. Length of crosscuts per slice: 100 X 100 = 10 000. Ore from crosscuts per slice = 10 000 m X 20 m2 X 3.5 = 700 000 t. Number of sublevel caving rounds per slice: 10 000/2 = 5000. Area for each blast in sublevel caving: 10 X 10 - 20 = 80 m2. Amount of ore per blast: 80 m2 X 6 m X 3.5 = 560 t. Extraction: 100% (see extraction curve Fig. 12). Loaded ore per blast: 75% or 420 t. Loaded waste per blast: 25% or 140 t. Total: 560 t. Total amount of rock from each blast in the sublevel caving: Ore: 560 t of which 2 X 70 = 140 t from develop¬ment work and 420 t from sublevel caving. Waste: 140 t. Total: 700 t. The ore needed per year is 3 X (66-6)/42-6 5 mil¬lion t. Necessary number of blasts per year= 5,000,000/ 560 = 8929. Distance to develop per year = 8929 blasts per year X 2 m per blast 17 858 m. Total amount/year: Ore from development work 17 858 m x 70 t/m = 1.25 million t/a Ore from sublevel caving: 8929 blasts per year X 420 tons per blast = 3.75 million t/a 5.00 million t/a Waste rock dilution: 8929 blasts per year X 140 tons per blast 1.25 million t/a Total amount to hoist 6.25 million t/ a The amount of ore from development work will in¬crease a little if the horizontal drift is placed in the ore body and not in the footwall. In this example the ore loss in 20%, and the waste rock dilution is also 20%. After taking the ore loss into account, the lifetime for 100 m of the ore body will be:

Jan 1, 1982

By Yu. A. Polozov, V. A. Lagunov, O. Yu. Lushinkova, Yu. I. Svirskiy, Eh. Ya. Kipko, Roy A. Williams

The STG integrated method of grouting can be divided into the several phases as outlined in preceding chapters. For convenience in describing technical procedures, they can be grouped as: 1. Investigations in non-geotechnical, exploration bore¬holes. 2. Drilling the holes necessary for geotechnical investiga¬tions and for grouting. 3. Conducting appropriate hydrogeologic tests in those holes and consequent calculations. 4. The preparation of a clay mortar. 5. The preparation of a clay-cement grout with additives. 6. The injection of the grout. 7. Checking the quality of the grout curtain. Items 2, 4, 5 and 6 are discussed below. These activities contain the procedural aspects of grouting. 7.1 DRILLING GROUT HOLES Grout holes belong to a very select class of drillholes. The necessary drilling equipment must enable the operator to drill the holes in inclined, twisting directions. In addi¬tion, the equipment must permit drilling under structurally and hydrogeologically complex conditions. The equipment must permit the operator to conduct specific testing activi¬ties in the drillholes. These activities include hydrodynamic analyses, flowmetric analysis, and the installation and re¬moval of deflectors, packers, grouting plugs, casings, lin¬ers, pumping facilities and other work. As explained in Chapters 5 and 6, the grouting of sat¬urated rock is conducted both through holes drilled from the surface and through holes drilled from the face of a shaft, drift, or tunnel. The drilling of grout holes from the surface can be carried out by an aggregate of equipment that can be the same equipment used for drilling exploration boreholes. Depending on the projected depth of the holes, the STG ZIF- 1200MR and ZIF-650 drilling rigs (or modifications of them) are used. The SKB-4, SKB-5 and SKB-7 high-output drilling rigs (workover rigs) have been used in recent years. The STG BMP-24 drilling rigs are used for carrying out the descent-lifting operations for drilling holes from the sur¬face. In a number of cases, the UKB-500C, URB-3AM and URB-2A power-fed drilling equipment is used for drilling holes from the surface. It should be noted that the drilling of grout holes usually requires an electric drive assembly. Drilling with diesel drive assemblies would be used only to preclude the possi¬bility of losing electric power during drilling operations. Turbine drilling would be used only for appropriate techni¬cal-economic reasons. The selection of the grout hole design is determined by the hydrogeological and structural geological conditions at the site as interpreted in Chapters 2 and 3. The design of grout holes must be as simple as possible in order to min¬imize costs. Hole design guidelines can be adopted as a basis for this purpose, unless site-specific conditions require otherwise. The mouth of the drillhole must be outfitted with a guide-pipe having a length of at least 2 m and an outside diameter from 219 to 234 mm. The upper part of the hole must be attached by a jig consisting of borehole casing that has a diameter ranging from 108 to 146 mm. The length of the jig h is determined by the equation [ ] where k = 1.1 to 1.2 is the load factor; P,, is the injection pressure of the grout into the mouth of the drillhole; D is the external diameter of the jig pipe; m = 0.6 to 0.7 is the work condition factor; T[ ].1 MPa is the bonding value of the rock cemented to the jig. The grout hole is drilled from the jig shoe to the de¬signed depth using a rock-crushing bit with a diameter of 93 mm or more. However in complex hydrogeological condi¬tions when the shaft intersects unstable rock, other hole designs can be used. The diameter of grout holes must permit an aggregate of investigations to be conducted in them using down-hole borehole geophysical and flowmetric logging instruments. It is necessary to cement the casing strings reliably in the grout holes, thereby permitting the injection of the grout under high pressure through the pres¬sure tight mouth of the borehole. Technological details for drilling grout holes such as the rotational rate of the drill bit, the axial load on the rock¬crushing bit, and the drilling fluid flow rate are optimized for the specific rock-hydrogeological conditions largely by experience. The hole diameter and type of rock crushing bit are important variables in these details of drilling. It is advisable to drill holes using water as the drilling fluid. However in those cases where the hole walls are unstable or under very high ground water pressure, the use of a well¬ engineered drilling mud should not be precluded. Unfortu¬nately, drilling mud can influence test results. When steeply dipping fractures with inclination angles of more than 60 to 70° are encountered, it is necessary to drill guided, inclined grout holes. This procedure permits the maximum number of fractures in each hole to be stu-

Jan 1, 1993

By Richard E. Ellwanger

Methods of utilizing flocculants as settling and filter aids for mineral processing slurries are reviewed. Broad chemical classifications and techniques for proper dilution, multiple addition, and combination treatments are discussed. A variety of custom built and commercially available systems for make up and delivery of flocculants to the application points are in use through- out the mining industry. Those concepts which, in the author's opinion, are particularly important to the successful make up and use of flocculants are presented in relationship to the available make up and feed systems. Actual industrial applications are included in the presentation.

Jan 1, 1980

By Donald G. Rogich

The concept of initiating a large action-oriented contract, directed toward inherently safe mining systems, was conceived by the U. S. Bureau of Mines in January 1970. At that time we were in the process of establishing research contracts and grants, about 100 of which were let in FY 71 to deal individually with fairly specific technological areas. These projects in the aggregate covered a wide spectrum of health and safety problems. What appeared to be necessary was the creation of a project or program that would provide a focal point for the demonstration of many of the results of this research and also in the action sense culminate with working hardware and systems that could be tested and demonstrated over a fairly long teen. The concept of working demonstrable systems, rather than just a conceptual study, was, felt to be necessary for two significant reasons. In the development of any new system, the translation from concept to working hardware is usually a costly and time consuming process which acts as a deterrent to implementation. Secondly, many decisions in the mining community to change equipment or systems ,are based on first hand observation of the new system, in operational practice, an attitude which is certainly understandable in view of the high capital costs of equipment. The decision was made to procure a single R&D contract which would be aimed at developing underground coal mining systems which

Jan 1, 1972

By Rainer Antretter

The city of Garmisch-Partenkirchen in southern Germany is located at a main transit road to Tyrol in Austria and suffers of a very heavy traffic load. Therefore, the Kramertunnel as a by-pass tunnel is built to release/mitigate the traffic through the city centre. The 3,600 m long single tube road tunnel is designed with a parallel but smaller emergency tunnel and with cross passages, fitted with single- and doublesided emergency bays, a vent shaft, and an intermediate ceiling to separate fresh air supply from the road traffic. The tunnel, concrete lined along its entire length provided the challenge to find smart formwork solutions for quick set-up, repositioning, setup and pouring. Three particularly specific sections are discussed in this paper.

Jun 13, 2023

By Jerry L. Fuller

Fan performance graphs are generated by digital computer using two programs, RUN- FANS and FANPLOT. RUNFANS calculates fan performance data from stored specific-volume, specific-speed data for a given fan type with appropriate allowances for fan diameter, rotational speed and air density. FANPLOT accepts specifications for drawing the graph and accepts either user-supplied pressure-quantity data or RUNFANS- calculated data as input, Operational procedures for both programs are detailed and examples of their interactive query routines are included. The hardware necessary to generate the graphs is illustrated. Several hardcopy output options are discussed,

Jan 1, 1984

By Ellen S. Forbus

Reduction bleaching is used to improve the brightness and color of the kaolin pigments sold to the paper and speciality industries. The bleach re¬duces the iron oxide associated with kaolin deposits to a colorless form by the following reaction: Na2S2O42+ 6Fe+3 + 4 H2O -> 2 NaHSO4 + 6Fe+2 + 6H+ (Conley et al., 1964). At present, sodium hydrosulfite is used by the kaolin industry as the reductive bleach. It is often purchased commercially as a liquid solution and added into an acidified slurry. Before the use of commercial sodium hydrosulfite, kaolin plants manufactured zinc hydrosulfite on site by adding zinc dust to sulfurous acid made by passing SO2 gas into water. This process was abandoned in the 1970s due to environmental concerns about zinc in waste waters. In the 1970s, Engelhard patented a process that made sodium hydrosulfate from an iron hydrosulfate (Tiethof, 1978). Difficulties with separating the iron hydroxide byproduct from the bleach and a decrease in the cost of commercial bleach caused the project to be abandoned.

Jan 1, 1993

By Wolfram Schnabel

Recently Lurgi has succesfully commissioned Peru's first direct reduction rotary kiln at SIDERPERU?s Chimbote works. The order included comprehensive engineering services and supply of special equipment to modify three existing cement kilns according to the SL/RN process. The kilns were cut to 62m length and installed with a slope of 2.5%. A new heating system, including shell burners, was supplied and inlet and outlet ends of the kilns completely renewed. Figure 1 shows the kilns after modification.

Jan 1, 1981

By A. Leppala

Scope of the Courier 300 System The fact that reliable on-stream analysis is a prerequisite for effective flotation control is hardly disputed today. Nevertheless, up to now no system has been available that includes all the equipment necessary for successful analysis. However essential an on-stream analyser is in itself, reliable and accurate assaying can only be assured after techniques for sampling, handling the slurries and computing the X-ray data have been developed for the purpose. The Outokumpu Company's Courier 300 System is a complete package that can be installed and handed over with the key. It includes the equipment needed for sampling and handling the slurries. It has been developed from the start to meet industrial demands. Obviously an on-line system must comply with far stricter standards than one designed for a laboratory. Assays are computed by an Outokumpu 316 digital data processor, which is an integral part of the system and controls its entire performance. The computer software is programmed as a standard package, including a highly advanced new model for assay computation. Analysis output is available for a process computer, report typewriter:, and recorders. The package also includes calibration for slurry assays at our pilot installation before delivery. A complete Courier System can analyse up to 4Z slurries and six elements in each slurry. Thanks to its modular design, it can be dimensioned initially to the customer's requirements and is easy to expand later at low cost. Being a mining company itself, Outokumpu has been able to utilize its own long experience in non-ferrous metallurgy - an important factor contributing to the success of the Courier system. History of the project and present installations The first on-stream analyser was installed at Outokumpu'a Pyhasalmi Con¬centrator at the end of 1967, after several years' development. Since then,

Jan 1, 1971

By Michael G. Nelson

In 1992, the Alaska Department of Environmental Conservation received a grant from the Environmental Protection Agency (EPA) to fund the reclamation of an abandoned placer mine. The project also included the development of a water-quality and hydrologic-monitoring program. The grant was provided under Section 319 of the Clean Water Act and is administered through EPA's Region X Water Division. For the past 100 years, Alaska's interior has been the site of extensive placer-mining operations. Early surface and underground operations left small tailings piles, some of which are still visible. Dredging left larger tailings piles, similar to those in California and elsewhere. The only reclamation of these tailings involved use as road base and fill and other civil applications. Most active mines in Alaska are on state and federal lands. The standards of reclamation for mines on federal lands are established under US Mining Laws, 43 CFR 3809. They address only mines operated since 1981. Under a state statute passed in 1990, the Alaska Department of Natural Resources, Division of Water and Mining, has issued reclamation regulations. These regulations apply to sites on state, federal and private lands, but only those mined since Oct. 15, 1991.

Jan 1, 1995

In conjunction with steady increases in production levels, long-wall operators have applied greater quantities of ventilating air to control respirable dust and methane gas. As a result, air velocities greater than 7.6 m/s (1500 fpm) have been measured on longwall faces. Operators have expressed concern over the potential entrainment of respirable dust at these high-velocities, especially during shield advance as dust falls from the shield canopy directly into theair stream. Laboratory tests to simulate dust liberation by shield movement were conducted at the Pittsburgh Research Laboratory of NIOSH in a wind tunnel designed to study dust entrainment in high-velocity airstreams. Dust was introduced into the tunnel to determine dust concentration as it relates to entrainment, dilution, air velocity, and particle adhesion. Airborne dust samples were obtained by iso-kinetic sampling using BGI cyclones to quantify respirable dust concentration at the various air velocities. Laboratory tests were con-ducted at velocities ranging from 2.0 to 10.1 m/s (400 to 2000 fpm),and significant differences in airborne respirable dust levels were measured. This research is being conducted to provide fundamental information on the entrainment characteristics of respirable dust at high air velocities, which will subsequently lead to solutions for shield dust control. A discussion of the test procedures and results are presented.

Jan 1, 2004

By Rod A. Levander, Kenneth B. King

INTRODUCTION The Panna Maria Uranium Project is located in South Texas, between San Antonio and Corpus Cristi, approximately 10 kilometers (6 miles) north of Karnes City, Texas. The tailings disposal facilities are located immediately south of the mill area and the central portion of the west pit. The mine and mill drainage pond is located north of the tailings pond. Location of the facilities is shown in Figure 1. The tailings pond is a disposal area for mill process wastes and has a capacity for storage of approximately 9 million metric tons (10 million tons) of tailings. This capacity is adequate for approximately 10 years of milling at a maximum rate of 2,700 metric tons (3,000 tons) per day. The tailings disposal facilities were designed to essentially eliminate discharge of contaminated waters to preclude degradation of surface streams or ground water. Water levels in the ponds will be maintained. through reuse in the mill and by evaporation. WASTE CHARACTERISTICS The sources of waste that is stored in the tailings pond include runoff from the mill area and tailings from the mill processing. The tailings consist of a sand slime slurry; the percentage passing the No. 200 sieve varies depending on the ore material, and it is generally in the range of 10 to 25 percent. The tailings have a density of approximately 1.2 metric tons per cu m (75 lb per cu ft) and an average specific gravity of 2.55. The liquid effluent from the mill consists of waste solutions from the grinding, leaching, extraction, and washing circuits of the mill. These solutions have an initial pH of 1.5 to 2.0 and contain the remnants of the leaching agents used in the mill process, sulfates, some silica as the primary dissolved solid, and trace quantities of soluble metals. This liquid is discharged with the solids into the tailings pond and is diluted by rainfall and runoff from the tailings dam. Runoff from the mill area, drainage from the mine area, and de-oiled water from truck washing facilities is discharged into the mine and mill drainage pond. Runoff from the mill area drains approximately 28 hectares (70 acres) from offices, shops, the mill site, the ore pad, haul roads, and adjacent areas. Mine drainage is collected in the mine area and pumped to the mine and mill drainage pond.

Jan 1, 1980

"The National Mining Hall of Fame and Museum (NMHFM) announced the 2017 National Mining Hall of Fame inductees. This year’s inductees, selected by the National Mining Hall of Fame’s Board of Governors, represent exploration and extraction of new frontiers, environmental stewardship, leadership in formulating U.S. mineral policy, education, and research and development, including the use of computers in planning, designing and managing mineral industry operations. The contributions of these individuals have undoubtedly had a significant and lasting impact on the mineral and mining industry. These individuals were selected for being visionary leaders, innovators, authors, pioneers in corporate social responsibility, and long-standing advocates for the U.S. mining industry.Dr. Thomas V. Falkie, Leonard Harris, Dr. Vincent E. McKelvey, and Gordon R. Parker will join 236 other mining industry luminaries when formally inducted into the National Mining Hall of Fame on Sept. 23, 2017. The 30th Annual Induction Banquet and Ceremony will be held at the Pinnacle Club, Grand Hyatt Hotel in Denver, CO.2017 National Mining Hall of Fame inductees:Dr. Thomas V. Falkie — In a career spanning six decades, Falkie’s accomplishments in industry, academia, government and professional societies demonstrate a pattern of integrity and sustained excellence. His gravitas and management style left highly favorable impressions in every position he held. He was the chairman and president of Berwind Natural Resources Corp.; President of SME; President of the American Institute of Mining, Metallurgy and Petroleum Engineers; Director of the U.S. Bureau of Mines and head of the Department of Mineral Engineering at the Pennsylvania State University. He played major leadership roles in the American Mining Congress, National Coal Association, Mining and Metallurgical Society of America, and the National Mining Association. He served on the board of directors of Foote Minerals and Cyprus-Amax and was very active in the National Academy of Engineering, the SME Foundation and the National Mining Hall of Fame and Museum.Leonard Harris — A highly regarded metallurgist and business executive, Leonard (Len) Harris may be most remembered for the heart he has for the people whose lives were touched by his career. For more than six decades, Harris has been a true pioneer in corporate social responsibility, leading companies to understand that doing the right thing for the local people is also the best path to business success. After an early career in Australia and Ghana, Harris moved to Peru in 1955 to join Cerro de Pasco Corp., owner of several mines with one of the most complex metallurgical operations in the world. Harris was quickly promoted through multiple positions and was ultimately named director of metallurgy."

Jan 8, 2017

By K. C. Vories

Surface mining and reclamation has the potential to at least temporarily increase surface runoff and resultant erosion and gully development. This increase in erosion is due in part to compaction of the soil surface with heavy equipment, creation of large relatively unvegetated watersheds, and elimination of natural dendritic ephemeral drainage patterns. Methods for stabilizing gully channels which may develop prior to establishment of sufficient vegetation to control erosion are analyzed. Utilization of various sizes of riprap for channel lining, the use of riprap check dams, reinforcement of riprap check dams, and the relation- ship of type of control structure to area of watershed and resultant flow velocities are discussed.

Jan 1, 1986