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By Raymond T. Moore

The Federal Coal Mine Health and Safety Act of 1969 (FCMHSA) begins with this statement: "Congress declares that the first priority and concern of all in the coal mining industry must be the health and safety of its most precious resource -- the miner; . . ." At the Federal level this responsibility is shared by the Department of the Interior and the Department of HEW. The health research and standard setting activities under the Act are largely the responsibility of the Department of HEW, and with the exception of Title 4, Black Lung Benefits, have been delegated to our Institute, which I will refer to henceforth as NIOSH. In addition, we bear certain joint responsibilities with the Department of the Interior. These include dust sampling and respirator approval. To complete the picture, the Department of Labor has recently assumed Black Lung Benefit respon¬sibilities from the Social Security Administration under Title 4 of the Act.

Jan 1, 1974

The floatability of a bituminous coal in NaG solutions was evaluated using a modified Hallimond tube to delineate the role of the electrostatic interaction between bubbles and particles in determining the coal hydrophobicity. Zeta potential measurements showed that bubbles are negatively charged in the entire pH range tested, while coal particles are positively charged below pH 6.0 and negatively charged above it. Also, both sodium and chloride ions were confirmed to act as indifferent ions without any specific effects for both coal particles and bubbles. Flotation as a function of pH exhibited a maximum and minimum at low salt concentrations which is shown to be determined mainly by the coal hydrophobicity as measured by a new hydrophobic levitation technique. At high salt concentrations (above 0.1 mole/dm3), the flotation without such maximum or minimum is controlled by the electrostatic interaction between the bubble and the particle.

Jan 1, 1992

By L. H. Munson, D. E. Hadlock, L. F. Munson, R. L. Gilchrist, P. D. Robinson

All uranium mills are required to perform sampling and analysis for radioactive particulates in their gaseous effluent streams and in the environment. Pacific Northwest Laboratory was requested by the U.S. Nuclear Regulatory Commission (NRC) to provide technical assistance to them for their Uranium Mill Health Physics Appraisal Program. In conducting appraisals, air sampling methods used at NRC-licensed mills were reviewed and several deficiencies noted. This paper includes only environmental and effluent particulate sampling although much of the information is applicable to both in-plant and environmental samples. First, the components of a proper sampling program are discussed: program objectives, program design, sampler design, analyses, quality assurance, and data handling. Then the specific deficiencies, or the "pitfalls" from the first 8 mill appraisals are discussed. The first consideration in establishing an air sampling program is defining the objectives of the program. What is air sampling suppose to accomplish? Many of the deficiencies we have observed have resulted because the desired objectives were not clearly established in the minds of the radiation safety staff. PROGRAM OBJECTIVES An environmental air sampling program ought to fulfill the following seven objectives. The first is to: 1) [demonstrate regulatory compliance]. Although a goal of most programs, regulatory compliance, is not well understood. One has not only to comply with the conditions of the source materials licensee, but one must also demonstrate compliance with 10CFR20 and 40CFR190. For example, 10CFR20.106 states: "A licensee shall not possess, use, or transfer licensed material so as to release to an unrestricted area radioactive material in concentrations which exceed the limits specified in Appendix B, Table II of this part .... For purposes of this section, concentrations may be averaged over a period not greater than one year." Even if a mill's license does not require sampling at the site boundary of maximum concentration, a sample may be necessary to demonstrate compliance with 10CFR20. Most mill personnel are painfully familiar with 40CFRl90.10, which states: "Operations.... shall be conducted in such a manner as to provide reasonable assurance that: (a) The annual dose equivalent does not exceed 25 millirems to the whole body.... of any member of the public as the result of exposures to planned discharges of radioactive materials, radon and its daughters excepted... from uranium fuel cycle operations..." This means a licensee's sampling program must give "reasonable assurance" that the member of the general public receiving in the most exposure gets no more than 25 millirems per year. The sampling program necessary to provide that assurance may or may not be a license requirement. However, merely meeting the license requirements and the explicit regulatory requirements does not necessariarly ensure an adequate effluent and environmental air sampling program. The second objective of the environmental air sampling program, is to 2) [identify the source(s) of contaminants]. This will include not only the routine program, but special sampling for verification of sources and nonsources. Only after sampling can a mill operator be assured that roof vents, laboratory hoods, and other localized ventilation systems are not making a significant contribution to environmental releases. An environmental sampling program should also allow the mill operator to fulfill the third objective, to 3) [estimate exposures]. Even before 40CFR190, a sampling program should have provided the mill operator with the information necessary to determine the dose to the "fence post" person, or at least to determine if doses were well below the 10CFR20 limits previously allowed. The program should 4) [detect and measure unplanned releases]. If there is a fire, a scrubber failure, or if a drum of yellowcake breaks open, measured releases will almost always be lower than conservative estimates. Whether or not a system to provide sampling during accidents is needed is almost always a cost-benefit decision. In general, uranium operations do not sample just in case an accident may occur. Yet they may decide on continuous air sampling in lieu of intermittant sampling partially because of the potential for accidents. Another objective of air sampling is 5) [to provide information on the effectiveness of control systems]. This is always a concern with new or modified equipment and may dictate sampling frequency in other situations as well. For instance, if a small leak in a bag filter cannot be detected by other means, then more frequent stack sampling may be indicated. A routine effluent and environmental monitoring program should also fulfill the sixth objective,

Jan 1, 1981

By L. U. Spellman

Atlantic Cement Company's new multimillion dollar, 10,000,000 barrel per year cement plant went into full operation in February, 1962, bringing into reality a new concept in the distribution of Portland cement. The Cerro and Newmont Mining Corporations, well established in the mineral extraction and dressing industry, backed the venture. To take advantage of the, economics inherent in single production units of large capacity, it was necessary to first find a market' capable of absorbing such large quantities. Cement can be economically shipped by rail and truck about 200 miles. Beyond' that radius from the producing facility the freight costs become prohibitive. No single marker area within that radius exists which could absorb such a large volume of cement. However, water transportation provides a relatively inexpensive method of transporting bulk products many times over such a distance. Thus, it was decided to locate the producing facility near a deep water port which had ready access both to the Atlantic Ocean and, just as important, a good source of raw material. An extensive feasibility study was made and the site at Ravena, New York on the Hudson River near Albany was chosen. Here, vast quantities of limestone in the foothills of the Catskill Mountains are found within a short distance of-the deep-water Hudson River.

Jan 1, 1964

By P. Shang

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

Jan 1, 2010

By Richard Giffen, Martha Gross, Luca Pellegrini, Pa Ousman Njie

The Hampton Roads Bridge-Tunnel (HRBT) Expansion project in Virginia includes parallel 1.5- mile (2.4 km) tunnels constructed using a tunnel boring machine (TBM). The TBM launching and receiving shafts were excavated within the footprint of two reclaimed islands abutting the navigation channel for the Port of Virginia. The shaft excavations—a circular tri-cell shaft at South Island, and a circular-rectangular twin-cell shaft at North Island—were supported by slurry walls up to 190 feet (58 meters) below the island surfaces. This paper describes specic design considerations for these shafts, as well as construction and uality-oversight aspects of their excavation and construction.

Jun 23, 2024

By Clyde N. Garman

The Homestake-New Mexico Partners consist of Homestake Mining Company of Lead, South Dakota; Rio de Ore Uranium Mines, Inc; United Western Minerals Company; White, Weld and Company; J.H. Whitney; San Jacinto Petroleum Corporation; and Clyde Osborn, Homestake Mining Company is the general partner, the others are limited partners. The Rio de Ore Uranium Mines, Inc. has. a mine in the Ambrosia Lake area; this was the first mine to go into production in this area. The United Western Minerals Company also has a mine in the Ambrosia Lake which is operated as a "farm out" from the San Jacinto Petroleum Corporation. These mines are the principal sources of ore for the mill. This group was the first to obtain a contract with AEC to make uranium concentrate from Ambrosia Lake ores and the first to have a mill in operation specifically for these ores. With Clyde Osborn as the sparkplug and co-ordinator holding the ore suppliers of, this group together, a contract with AEC was agreed on as to its essential points by mid-summer, 1956, At that time, there was no general partner and no financing, so me formal contract could be signed. By December, 1956 when the contract was signed and the present partnership officially formed, much of the basic engineering was done and purchasing of main elements of the mill waited on the formalizing of agreements, at the specifications and sizes agreed on previously. Ground for the mill was broken in April, 1957. The sampling plant went into operation in October and ore was first fed to the ball mills on February 5, 1958, ten months after construction actually started. Filling of the circuit with sodium carbonate bicarbonate solution had begun a week before that.

Jan 1, 1959

By Yashar Pourrahimian, Roberto Noriega

Truck fleet dispatching plays a crucial role in reducing operational costs and fulfilling operational targets in open-pit mining operations and is subject to large uncertainty arising from the operating cycles of trucks and loading equipment. This paper proposes a reinforcement learning-based truck dispatching system. Reinforcement learning is a machine learning area that deals with learning an optimal sequential decision-making strategy in an uncertain environment. An open-pit load-and-haul simulation is developed that also captures the truck movements and interactions in the shared road network, and a Neural Network is successfully trained to suggest truck dispatching decisions in a real-time manner.

Jun 25, 2023

By J. M. Mutmansky, A. Wang

This paper defines the elements of a basic economic model for decision making when considering a methane drainage system for an underground coal mine. A drainage system entails significant capital and operating expense; hence the decision to utilize drainage must be made carefully. The model outlines the basic structure of decision making and considers the costs and benefits when the methane is marketed and when the methane is vented to the atmosphere. The effects on mine safety and the dust levels in the mine are also considered, both in a general format and as economic variables. Sources of information for executing this decision making are provided for an actual mine decision.

Jan 1, 1999

By H. A. Zollinger

The Hallmark Distribution Center is one of the most sophisticated material handling and order filling facilities in the world. The 53 million cubic foot facility houses an ultra-modern, computer- monitored distribution complex that handles as many as 1/4 million orders per day. The Distribution Center replaces 16 leased buildings scattered through- out metropolitan Kansas City and, in addition, re-leased 4 floors in mid-town Kansas City needed for creative and administrative expansion. This new facility is the nerve center for distribution of Hallmark products in United States and Latin America. The size and gross numbers of all parts of the system is a significant accomplishment, but the purpose of this paper is to explain the technical advancements in the state-of-the-art of material handling and controls. The system iteself is made up of seven sub-systems including receiving, warehousing, picking rack stocking, towline, order filling, order sorting, and shipping. Significant techniques were used in each of these areas as well as technical advancements in the state-of-the- art. The most significant points are in 4 of the areas and are discussed in this paper.

Jan 1, 1973

By Russell K. McFarland, Eugene L. Foster

INTRODUCTION The U. S. Department of Transportation has underway an important new program which will have a major impact on rapid excavation technology. The Transportation Tunneling Program, as it is called, is a coordinated, multi-modal research and development effort. Its goals, if realized, will significantly improve our ability to build the underground structures needed for transportation. This, in turn, will improve transport efficiency, environmental impact, and the energy consumption associated with the movement of people and goods. Tunneling technology research and development had its beginning at the Department of Transportation in the Office of High Speed Ground Transportation (OHSGT). The OHSGT developed and implemented a program in 1965 to provide the technology for underground construction needed to support future high speed ground transportation. In 1967, when the OHSGT was transferred from the Department of Commerce to the Federal Railroad Administration (FRA), the program accompanied that office. The thrust of the FRA program has been cost reduction through the development of new materials, innovative designs, and better construction methods. During the late 1960's and early 1970's, other developments were underway which would influence the future of tunneling research at the Department of Transportation. An ad hoc

Jan 1, 1974

By G. E. Tooker

This paper (1) presents new data on the use of horizontal curves to optimize the alignment of belt conveyors. The operating concept of a horizontal curve is simple. As an element of the belt passes through the curve, it is motivated to drift toward the center of the curve by unbalanced tension forces in the belt. This lateral drift is resisted by the forces of friction and gravity, which in turn can be stated as a function of drift. Resisting forces, as a function of drift, are stated in terms of variables such as the amount of load on the belt, and parameters such as the trough angle, tilt angle, and super elevation angle, and number of rolls in the idler. The trick is to determine that the belt will drift to a position of equilibrium within predictable limits, without physically constraining the edge of the belt. In practice this prediction is not easy to make without the aid of a computer. The motivating force is easy to calculate, but its value is continually changing throughout the angle subtended by the curve arc. The resisting forces are constant throughout the curve for a given drift and load condition, but the calculations are very complex. Data in this paper will assist the conveyor designer in making preliminary calculations for horizontal curves. Presented is the equation for calculating the motivating force, and a family of curves that show the resisting force as a function of lateral drift for some commonly encountered conveyor design criteria.

Jan 1, 1985

By F. Woodcock, A. R. Laplante

A test to characterize the amount of gravity-recoverable gold (GRG) in an ore is described. Typical GRG results are given and possible uses are discussed. The overall database, which includes 68complete tests, is presented. The ore samples treated had an average GRG content of 63% of the total gold in the sample, with a standard deviation of 20% and a range of 3% to 97%. Both the F8(, of gold and the GRG content at a grind of 100% finer than 850 pm correlate well with the overall GRG content (at 80%finer than 75 pm). The primary use of the test is to determine whether gravity recovery should be used and how. Results can also be used to predict gravity recovery, as many of the ores tested are from plants employing gravity recovery. Gravity-circuit simulation can be used to refine recovery estimates or for optimization studies.

Jan 1, 2000

By James J. Scott

In the fall of 1976 the author started test work with Friction Rock Stabilizers in uranium mines of the West, principally in the Ambrosia Lake and Churchrock districts of New Mexico. Tests were also conducted in other uranium mines in the Rocky Mountains area. These mines are plagues with problems in ground control due to the weak formations in which mineralization occurs, mudstones, siltstones, weak sand, etc. For this reason, it is extremely difficult to obtain good anchorage for long periods of time with conventional mechanical roof bolts. Resin bolts give good anchorage but are expensive and, because of hole erosion and difficulties in installation due to inadequate equipment for mixing the resin and placing the rebar, they are not widely used. Field testing was also carried out in trona, limestones and hard and soft shale formations. The mechanism of the Friction Rock Stabi1izer support is discussed and pull test data presented for various rock types.

Jan 1, 1977

By John P. Capp

In recent years limited markets have been developed for fly ash, the dust removed from coal-burning powerplant stacks, but most of it is still dumped in spoils areas at a cost ranging from 20 cents to $1.75 per ton. Aside from this cost, the creation of huge spoils areas can present a considerable aesthetic problem. Since the present annual fly ash output of about 20 million tons will probably reach 30 million by 1970, and because satisfactory disposal areas are becoming more limited, markets for much larger quantities of the waste are needed to keep disposal costs from becoming a significant economic factor in coal-burning powerplant operation. Current stress on air-pollution control and beautification, plus the vital need for good powerplant economy, makes it imperative, therefore, that coal producers and consumers expand markets and develop new applications for fly ash. Markets for established uses can be increased by making a greater effort to sell fly ash. New large tonnage markets for fly ash should be sought via more intensive, coordinated research. The economics of fly ash utilization underscores the vital role that must be played by research. To be competitive with other products, processes for the conversion of fly ash into marketable materials face difficulty in regard to two important economic factors--transportation cost and product utility--the other economic factors are favorable. Raw material costs of fly ash, for example, are quite attractive, and supply is no problem because there are many coal-burning powerplants in operation and many more are planned. Demand for products made from fly ash will grow if their utility is established and a good sales program is initiated. The major problems then are transporta¬tion costs and development of useful products.

Jan 1, 1966

By G. W. Heunisch

The properties of Neutra-Fix® and Neutra-Ment®, two new lime substitutes for treating acid mine drainage (AMD), have been compared with lime and Allcament®, two products presently in use for AMD treatment. The two new products are basically dolomitic byproducts and produce sludges that are more compact than those from lime. Sludge settling rates are faster than lime with iron concentrations after 24 hours that comply with Environmental Protection Agency (EPA) regulations. Material utilization and optimum pH are reported.

Jan 1, 1988

By G. M. Bernard

Cerro Colorado lies on the eastern edge of the Atacama Desert in the foothills of the Andean Cordillera of northern Chile. Compañía Minera Cerro Colorado SA (CMCC) operates Cerro Colorado. CMCC, headquartered in Santiago, Chile, is wholly owned by Rio Algom Ltd., of Toronto, Ontario. Cerro Colorado is located 120 km (75 miles)east of the port city of Iquique. Access is by 30 km (19 miles) of paved highway and 70 km (43 miles) of upgraded road. The mine site is located at an altitude of 2600 m (8531 ft) on a gentle west-sloping plateau adjacent to a deep canyon (Quebrada de Parca) to the north. Temperatures are moderate, ranging from 5° to 30° C (41° to 86° F) with an average annual rainfall of 20 mm (0.8 in.). The plateau is generally covered with 20 to 30 m (65 to 100 ft) of Quatemary sand and gravel overlaying bedrock. In the immediate vicinity of the Cerro Colorado deposit, a semicircular embayment has been eroded into a steep canyon wall that cuts through the surface gravels to expose a considerable section of the underlying bedrock.

Jan 1, 1995

By T. Faulkner, S. A. Richards

"The Scale-Distance formula is one of the primary means of determining the maximum amount of explosives that can be safely detonated at one time by a single delay. This paper describes a method of applying the Scale-Distance formula to the entire mining area using gridded surfaces. Using this technique, the operator can better determine the economic impact of nearby structures on the mine plan. INTRODUCTION As the surface mining of coal and stone encroaches near populated areas, precautions must be taken to minimize blast vibration damage to protected structures. The common method employed to minimize vibration damage is not to reduce the total amount of explosive in the hole (which would negatively affect fragmentation), but rather to introduce delays to reduce the amount of explosive detonated at any point in time. The Scale-Distance formula, an industry-accepted standard, may be used to calculate the maximum weight of explosive that can be detonated at one time without damaging the structure. This information may then be used to determine the number of delays required for each hole. Detonators make up a large part of the cost of blasting. At roughly $15 per detonator an additional detonator in the hole can be significant. It is normal to set off hundreds of holes at in one shot. An additional detonator in each hole can cost additional thousands of dollars per shot. The number of detonators is also a function of the depth of the holes and the hole spacing. Being able to accurately forecast the economic impact of blasting near structures improves a company’s ability to make informed decisions on how to approach property owners. Operators basically have three options when dealing with property owners: 1. Buy the property and blast without restriction 2. Negotiate with property owner for a waiver to allow unrestricted blasting 3. Comply with the legal blasting restrictions This paper proposes a method for the engineer to forecast for all points in the proposed mining area the impact of nearby structures upon the blast design. Being able to create a contour map and ultimately estimate the number of delays required for the entire forecasted mining area, the engineer can create accurate economic forecasts of the cost of blasting. The objective is to reduce the level of uncertainty in the forecast of the blast component portion of the forecast."

Jan 1, 2016

By W. C. Morgan

The Federal Surface Mining Law enacted in 1978 is now being translated into regulations which must be followed in future coal mining. Substantial change to mining procedures is required to maintain stricter air and water control while mining and to return the mined out land to equal or better use than before. These changes do not come easy; and in most cases, they create a substantial additional cost. Based on field observations and mining studies, Caterpillar has been making suggestions on the use of their types of equipment to conform to the new standards at the least cost. This paper will be a brief review of some of the overburden stripping and reclamation methods suggested by Caterpillar. A production and cost comparison of dragline, scraper/dozer and truck, loader systems in 20 to 150 ft. Overburden conditions illustrates potential cost savings using mobile equipment.

Jan 1, 1980

By Morris Loshinsky, George Ziegler

NEW ROUTES - 63rd STREET CROSSTOWN The New Route construction along East 63rd Street in Manhattan began in 1969 with the East River tunnel connecting Manhattan and Queens. The 63rd Street Line, once in Queens, is planned to connect to another new route called the Queens By Pass or Super Express (See Exhibit 1) which would connect to the Queens Boulevard Line at Forest Hills. The purpose of the Queens By Pass was to alleviate subway congestion to and from the Borough of Queens, whose population had rapidly expanded during and after World War II. The existing Queens Boulevard subway lines (the "E" and the "F" trains) are almost filled to capacity at their terminal stations with passengers from Long Island. Passengers boarding trains enroute from the local Queens stations have difficulty boarding crowded trains, and, at times, cannot board the trains. The New Routes, thus, were to give additional train capacity into Manhattan and thereby relieve the crowded conditions along the Queens Boulevard corridor. PROFILE - METHOD OF CONSTRUCTION The portion of the New Route passing east-west under East 63rd Street on Manhattan (See Exhibit 2) had to snake beneath intersecting structures running north and south, such as the Con Rail tracks below Park Avenue and the 80 ft deep Lexington Avenue Express track structure along Lexington Avenue. Further, the Lexington Avenue Local tracks are in a separate structure which has a high profile close to the street surface. Therefore the 63rd

Jan 1, 1981