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By McQueen LB

The Water Board has been involved in the development and ipgrading of sewerage facilities in the Blue Mountains since 1980. In 1984 the Board prepared a report that dealt with the Blue Mountains Sewage Effluent Management study. Successive 3ovemments have been concerned about development in the 3lue Mountains and the effect this development is having on the luality of the streams flowing into the Blue Mountains National ?ark (presently up for World Heritage Listing).

Jan 1, 1993

By H. M. Roche

MAGNETITE mining and milling in the Eastern States in 1939 showed considerable improvement over 1938. For the first eight months of the year production of magnetite proceeded at a normal rate but operations were stepped up in the last four months owing to increased domestic demand. In New York, the Republic Steel Corp. operated the Witherbee-Sherman mines at Mineville throughout the year. Chateaugay Ore and Iron Co. operated their low-phosphorus mine at Lyon Mountain for the first seven months, but on Aug. 1, Republic Steel took over this mine -and have since operated it. In Pennsylvania, the Bethlehem Steel Co, operated the Cornwall mine continuously. In New Jersey, Mt. Hops and Scrub Oak were in operation all year. The Washington mine went into production on Nov. 1 and the Richard mine on Dec. 1.

Jan 1, 1940

By R Mackay, J Brereton

On 30 June 2020, the Mine Land Rehabilitation Authority (the Authority) superseded the Latrobe Valley Mine Rehabilitation Commissioner as the independent overseer of Victoria’s declared mine rehabilitation. Currently, only the Latrobe Valley’s three brown coalmines are declared, with each mine at a different stage of rehabilitation and closure planning: Hazelwood ceased mining in 2017, Yallourn is scheduled to end mining in 2028 and Loy Yang in 2035. The three declared mines are very large, close together (Figure 1) and present significant environmental risks that must be mitigated during rehabilitation and post closure. In addition to fire risks, the brown coalmines are inherently unstable and require continuous monitoring and management of ground movements and groundwater pressures. Since 2007 several damaging events have occurred, highlighting the difficulties of achieving long-term stability, even with good landform design and rigorous ground control management plans

Aug 2, 2023

By R. W. Thompkins

"PREFACEPart 1 of this paper, published in the September issue, covered the occurrence of uranium, radiation from uranium ores, the uranium series, radioactive theory, radioactive equilibrium and application to the radon series, the working level, the theory of emanation and diffusion, transport by thermal diffusion of radon emanating from porous rocks, and definitions.The October issue carried Part 2, which dealt with radiation theory applied to uranium ores, other radon migration factors, factors affecting the radon gas release rate, the measurement of radon gas emanation rates, the tunnel concept, variation of emanation rate with grade and estimating radioactivity from grade analysis.Part 3, in this issue, concludes the series by discussing the techniques for controlling radiation and providing some example calculations.17.0. Techniques for Controlling Radiation17.1. Altering the Factors In the Diffusion EquationIt has been noted that radon gas emanates from the surfaces of exposed ore to the mine atmosphere. The diffusion laws establish the rate of this flow. The fundamental relationship is that the rate of flow (J) is a function of the pore concentration and the distance from the surface. It is expressed as: []If any of these terms is varied, either naturally or artificially, the rate of gas emanation will be altered.Altering the Diffusion CoefficientThe literature describes many ways to lower the radon gas emanation rates which are dependent on changing the diffusion coefficient:1. A layer of ice on top of a tailings dam or on a soil.2. Humid clayey materials and swamped soils over a radon source."

Jan 1, 1982

By Angus W. Davis

The case of the P. G. E. railway is a peculiar one. Traversing, as it does, to a large extent, a mineralized country there are as yet no producing mines along its route although I am convinced that mines will be developed in the region tributary to the railway. The Fitzimmons group of claims, a copper property near Mons station, 37 miles from Squamish is now (unless recently relinquished) under bond to the Granby Company. On Cadwallader creek, in the upper Bridge river country, certain gold properties, referred to later, are being developed. Prospectors are fairly active in the Pemberton meadows area. There are also a large number in the Bridge river, Gun creek, and Whitewater districts. East of Marguerite station some development work is being prosecuted on some copper claims located there. In addition here and there throughout the entire route of the railway prospecting is being undertaken. At Hat creek, 15 miles from Pavilion station there is an enormous deposit of lignite. It is by no means certain that this coal can be profitably mined and hauled to the railway, but as a cheap fuel it offers possibilities in the recovery of by-products by destructive distillation. Logical procedure would ? indicate the expenditure of considerable money on development and, if results justify, the construction of a spur from the main line to the deposit.

Jan 1, 1925

By Duk-Won Park

Since geologic anomalies are one of the governing factors of instability of underground openings, it is extremely important to know in advance the locations and extent of these anomalies such as faults and weak zones. At an underground coal mine in the Black Warrior Basin, core drilling was conducted to find a fault in an area where they were planning to locate longwall panels and possibly a shaft. Core logging did not provide sufficient information to delineate the exact location, strike, and dip of the fault. However, a high resolution reflection seismic study successfully solved this problem. This experience proved the seismic exploration technique could be used for premining coal exploration by reducing drilling costs and providing more accurate and detailed information about geologic anomalies.

Jan 1, 1988

By M. D. McInnis

The Jualin Gold Prospect is centered on Johnson Creek, approximately 40 air miles north-west of Juneau, Alaska. The property is on the southern end of the Kakuhan Range with Berners Bay immediately to the south and Lynn Canal to the west. The property is accessible directly by helicopter from Juneau or by float plane to the head of a 5.5 mile gravel road that begins on the north side of Berners Bay and terminates at the old workings of the Jualin Mine near the center of the property.

Jan 1, 1989

By B. I. Ferber

Toxic and explosive atmospheres are discussed, along with some of the instruments commercially available for their detection. No attempt has been made to evaluate the accuracy of anyone device. This circular has been prepared primarily to aid mine inspectors in selecting suitable instruments for underground gas detection.

Jan 1, 1972

By John V. Beall

As recently as 1964, the situation in the Australian iron ore industry was chiefly one of potential. The only producer was the Broken Hill Pty. (BHP). That company mined about 5 million tpy from deposits in the Middleback Range in South Australia and at Yampi Sound in Western Australia. No ore was exported from Australia. Now, just five years later, and after expenditures amounting to approximately one half billion dollars, BHP and seven new companies exported about 15 million tons (long tons) of iron ore and pellets as well as meeting Australia's own annual requirements of approximately 8.5 million tons of ore. Early this year, the volume of iron ore on order stood at 328 mil- lion tons to be delivered over a period of 15 years, but Cliffs Western negotiations for sale of Robe River iron ore have boosted the volume to the new high of 466 million tons. All of this has meant a great deal to Australia in terms of new income. In fiscal year 1967 (ending June 30, 1967) exports of iron ore amounted to $52 million; in 1968, $128 million and by 1'972 the Bureau of Mineral Resources expects the value of exports from iron ore to reach $242 million. In achieving the position of major- supplier of iron ore to the Japanese steelmakers, it was necessary to build a great many new facilities, mostly in Western Australia. Three railroads, 70 miles long, 182 miles and 265 miles were constructed. A new port was created at Dampier; Port Hedland was deepened and otherwise improved; both of these ports are in Western Australia. In Tasmania, Savage River developers built an offshore shiploading station that has received the recognition of engineers internationally. At least a half dozen new communities have been founded. The narrow gage railroad from Kalgoorlie to Perth and Freemantle was replaced with a standard gage line.

Jan 6, 1969

By AIME AIME

THE Wednesday morning session was devoted entirely to the consideration of the tentative code for coal mine ventilation. A. W. Hesse is chairman of this subcommittee. E. A. Holbrook presided at the session and assisted by A. W. Hesse and George S. Rice, gave the historical background of the movement for a ventilation code. They stressed the point that this was to be an engineer's code, and that it was hoped that it might serve as a valuable guide to operating companies in securing greater efficiency as well as safety in ventilation. The discussion was continued into the afternoon session, and by adjournment the entire' code had been covered.' Many sections were referred back to the Committee for further study and several new sections were suggested. The various opinions and new ideas brought out during the discussion proved very valuable and. contributed much to the progress being made in the preparation of this code.

Jan 1, 1929

By Scott Beer

What New Technologies Will Drive Economic Improvements? ??Historical ?1060?s: Mainframe Technologies ?1970?s: Mini Computing ?1980?s: Workstation Computing ?1990?s: Personal Computing ?2000?s: Network Computing Internet PDAs Cellular phones ??What?s the next technology improvement? ??What?s next for Mining?

May 1, 2009

R. V. NorHis, Wilkes-Barre, Pa. (communication to the Secretary*) : The electric-haulage plant of the Short Mountain Colliery of the Lykens Valley Coal Co., mentioned by Messrs. Stoek and Harris as the earliest underground electric plant in the United States (and, I believe, the second in the world), was started July 23, 1887. The plant, designed by W. M. Schlessinger, consists of two motor-cars, each weighing about 5 tons and equipped with a 32-h.p. Union Electric Go. motor. The original general construction of the motor-cars is shown by Mr. Stoek; but they were rebuilt, the same year, with some important improvements in design; and, except for strengthening the frames and replacing the original pig-iron weights by a casting, they have not been greatly changed since that time. The generating-plant consists of two Union Electric Co. dynamos of 65-h.p. each, driven by an old 18- by 48-in. plain slide-valve engine; the ordinary voltage is 450 and the amperage varies from 40 to 200; the average indicated h.p. of the engine is about 75, with a steam-consumption of about 75 lb. per i.h.p. per hour; and as the cost of steam at this colliery is 8.11 cents per 1,000 lb.,the steam-cost per day is about $4.56.

Jan 1, 1904

By Christopher Mark

Dr. Christopher Mark serves as Team Leader of the Rock Mechanics Section in the Rock Safety Engineering Branch of the NIOSH - Pittsburgh Research Laboratory. In this position he leads a multi-disciplinary team and conducts individual research directed towards fundamental ground control safety issues affecting miners. Dr. Mark is recognized as one of the country?s leading authorities on coal mine ground control. Through his research, he has made numerous important contributions to mine safety that have been widely adopted into mining practice. He is a highly original researcher, and has often developed new and innovative methods to tackle extremely complex problems in his field. In recent years Dr. Mark has also achieved wide international recognition. Five research projects in Canada, Australia, and South Africa have been based largely on his work.

Jan 1, 2007

By A Crosky, S Saydam, H Chen, H L. Ramandi

Cable bolts and rock bolts are used as primary and secondary anchoring systems in many underground mines. Reports on the premature failure of cable bolts and rock bolts due to stress corrosion cracking (SCC) in underground coalmines have been increasing in the past two decades. The previous studies found that the SCC in both rock bolts and cable bolts occur as a consequence of atomic hydrogen diffusion into the material, which is known as hydrogen-induced stress corrosion cracking, HISCC (Craig et al, 2016; Wu et al, 2018b). While research to understand the process of SCC occurrence in underground mines is still required, finding a prevention solution to protect the bolts from HISCC is crucial. In this study, we analyse a variety of commercially available coatings for steel corrosion prevention, including barrier coating (ie epoxy, polyester TGIC) and sacrificial coating (hot-dip galvanising). We test the coating on coupons manufactured from rock bolts and cable bolts used in the coal mining industry.

Nov 29, 2022

By David Sinclair, Philip B. Bucky

The dimensions and shapes of mine structures may at present be determined by (1) field experience, (2) structural calculations, and (3) barodynamic tests. § None of these, however, provide information as to the stresses, their direction and distribution in a mine structure. For the design of pillars, the placing of openings relative to working places such as gangways, haulage levels, etc., this information is desirable. Photoelastic methods provide this and, while relatively new, their application in all engineering fields is assuming increasing importance. This paper, therefore, will present the method with a few applications to mining, and with sufficient reference for further study by the reader. PART I The Photoelastic Method The photoelastic method of stress measurement determines the stress distribution in a two-dimensional model by optical means. It makes use of the fact that when a piece of isotropic transparent material, such as glass, celluloid, or Bakelite, is stressed and viewed in polarized** light a picture is seen which indicates by its color bands of light, or fringes, the magnitude of the stresses, their direction and their distribution. General Explanation The stress at any point 0 in a structure (Fig. I), may be resolved into two components, P and Q, each a pure tension or compression, at right angles to each other, called principal stresses.' To fully identify the stress, the values of P and Q and their directions or angle F must be known.

Jan 1, 1940

By K. M. Reim

Planning the development of the Quartz Hill molybdenum open pit mine in Southeast Alaska required a number of special considerations. Located in mountainous glaciated terrain, about 3.8 m (150 in.) of annual precipitation (with annual snowfall over 10.2 m (400 :in.) was a primary consideration. Mine planning included muskeg and snow removal, avalanche control, clearing timber, water quality control, dust control, seismicity, mine schedule, work force and reclamation. Quartz Hill is in an environmentally sensitive area which has required extensive environmental baseline data collection, four Environmental Impact statements (EIS) and a large number of permits.

Jan 1, 1988

By David Sinclair, Philip B. Bucky

The dimensions and shapes of mine structures may at present be determined by (1) field experience, (2) structural calculations, and (3) barodynamic tests. § None of these, however, provide information as to the stresses, their direction and distribution in a mine structure. For the design of pillars, the placing of openings relative to working places such as gangways, haulage levels, etc., this information is desirable. Photoelastic methods provide this and, while relatively new, their application in all engineering fields is assuming increasing importance. This paper, therefore, will present the method with a few applications to mining, and with sufficient reference for further study by the reader. PART I The Photoelastic Method The photoelastic method of stress measurement determines the stress distribution in a two-dimensional model by optical means. It makes use of the fact that when a piece of isotropic transparent material, such as glass, celluloid, or Bakelite, is stressed and viewed in polarized** light a picture is seen which indicates by its color bands of light, or fringes, the magnitude of the stresses, their direction and their distribution. General Explanation The stress at any point 0 in a structure (Fig. I), may be resolved into two components, P and Q, each a pure tension or compression, at right angles to each other, called principal stresses.' To fully identify the stress, the values of P and Q and their directions or angle F must be known.

Jan 1, 1940

By Törbjorn Naarttijärvi, Bengt Ludvig, Agne Rustan

"Falling rock is one of the major causes of serious injuries and deaths in Swedish mines. The research at the Division of Mining and Underground Construction was therefore directed toward controlled blasting in hard intense jointed rock.The project was started with an extensive literature review. Model tests with a new equivalent model material have been initiated to find ways of improving blasting techniques. The result showed that long cracks arise at the perimeter holes when there is a long time delay between adjacent holes. This led to the theoretical development of a new initiation method with ultra short delays (1,5 ms) f or controlled blasting, called ""Cutblasting"".Full-scale tests have been done at LKAB in Malmberget in hard intense jointed magnetite ore. Four different types of perimeter charges have been tested, namely: tube charges, ANFO mixed with plastic beads, detonating cord and linear shaped charges. Three types of initiation of the perimeter holes have been used, conventional (half-second delay detonators), instantaneous and ultra short ""cutblasting initiation"" (1,5 ms delay). The change in rock strength before and after blasting has been studied with bore hole periscope, vibration measurement and ocular observation of the rock surfaces.Thefull-scale tests showed that ""cutblasting"" with detonating cord in the perimeter holes gave the smallest damage to the surrounding rock. A combination of cutblasting initiation and tube charges are anticipated to give an even better result. A new method of controlled blasting using linear-shaped charges has also been tested, however, this charge type needs further development.The full- scale test also showed that the damage which can be seen on the rock surf ace is about the same for different controlled blasting methods but the not-visual-damage zone varies as much as from 0,1 to 0,7 m.A new classification system for controlled blasting regarding the damage to the surrounding rock has been devised."

Jan 1, 1985

By Howard J. Haselhuhn

The effectiveness of selective flocculation and dispersion processes for the concentration of hematite ore are strongly dependent on the ionic content of the process water. It has been noticed that magnesium ions are more detrimental to iron recoveries during gravity separation and flotation processes than calcium. This phenomenon was studied by measuring the zeta potential of hematite ore at various concentrations of sodium, magnesium, calcium, strontium and barium at a pH of 11. Results show that zeta potential inverts from negative to positive at concentrations as low as 0.16 mM of magnesium ions in the solution. It takes a significantly higher concentration (1.25 mM) of calcium ions to achieve the same effect. This difference is attributed to the ability of magnesium ions to adsorb to all surface hydroxyl groups, whereas calcium, due to its larger size, can only adsorb to every third hydroxyl group. This hypothesis was confirmed by results similar to those seen with calcium when this test was repeated with strontium and barium ions. The tendency for calcium ions to adsorb to every third surface hydroxyl group causes higher concentrations of calcium to be less detrimental to hematite concentration processes than magnesium.

May 1, 2012

By Ralph M. Roosevelt

IN AS MUCH as our Institute, by tradition, never adopts any official view of matters upon which difference of opinion exists, it may be taken for granted that the duty of its Production Control Committee does' not embrace the formulation of any general policy on that much-discussed subject. During the first years of its existence the Committee confined its activities to making arrangements for an annual general session at which the broader aspects of the general problem were discussed by men both within and outside the mineral industry. These general sessions, although interesting, did not indicate any definite path of progress, so during the last year the Committee has held a number of luncheon meetings at which the members might discuss in detail problems existing in the specific industries with which they are most closely acquainted, in the hope that discussions dealing with conditions rather than theories might result in the bringing to light of some general truths. Most of these truths have been fairly obvious from the beginning but they are of such basic importance that a periodic restatement of them seems worth while,

Jan 1, 1932