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By David L. Brostrom, William C. Brice, Perry A. Canton

The business of mineral exploration and development has become much more than simply a problem of locating orebodies and designing mines. Favorable economic analysis of mining and processing feasibility is no longer sufficient to justify the development of a mine. New laws, enacted by virtually every level of government, require comprehensive land use planning, environmental analysis, mineland reclamation, mine safety studies, and many other considerations. This profusion of new laws says in effect, that the mining company is no longer responsible only to its stockholders. Mineral development today can be compared to a partnership. As in all partnerships, the risks and liabilities as well as the benefits are held jointly by all the participants. In addition to the mining operator, this partnership consists of the public, through its many levels of government, interest groups, and individual citizens. Therefore, you'd better know your partner very well - his responsibilities and capabilities. Mining is considered a high risk venture. The risk on the part of the operator and the lending institutions has long been recognized. The risk that the public and its government take in these mining ventures has now been recognized also. The people and their government have learned that they inherit, through abandonment or forfeiture, the mistakes and problems of individuals and companies regarding these natural resources. In looking through the "Mining Engineering Handbook" recently published by the Society of Mining Engineers, I noted that in their discussion of liability for excavations, the authors quoted from the book of Exodus, 20th chap., where Moses said to his people: "When a man leaves a pit open, or when a man digs a pit and does not cover it, and an ox or an ass falls into it, the owner of the pit shall make it good; he shall give money to its owner, and the dead beast

Jan 1, 1974

By P. Dhar, H. R. Kota, M. Thornhill

A very high-grade calcite deposit located in northern Norway consists of CaCO3 ore with minor silicate and sulphide impurities. Cationic (Tallow-1,3-diaminopropane, Duomeen T) collector has been used in the purification of calcite by flotation with an aim of achieving calcite concentrate for its use in value-added products in a variety of industries. The feasibility of sulphide flotation from calcite by this cationic collector has been initially judged from Hallimond flotation and zeta potential on pure mineral systems and the results illustrate the removal of sulphide from calcite ore at neutral pH region. The adsorption mechanism of diamine on both the sulphide minerals was found to be the same by zeta potential studies. The variations in zeta potential are in good agreement with the adsorption of diamine molecular and ionic species as a function of pH. FTIR studies also showed the adsorption of diamine species in agreement with the zeta potential and Hallimond flotation results. Furthermore, the removal of sulphide impurities with selective flotation by diamine collector was performed in bench-scale flotation with the calcite ore and the results indeed showed that the calcite concentrate could meet the quality requirements for its use in the paper industry for coating and filler purposes.

By C. E. Jordan

The Tuscaloosa Metallurgy Research Center of the Bureau of Mines, U.S. Department of the Interior, is investigating the recovery of phosphate from beneficiation slime, as part of the Bureau's efforts to conserve mineral resources through increased use of wastes. Phosphate equivalent to about two-fifths of U.S. production is discarded annually in the wastes. Exploratory flotation tests on the plus 5-um fraction of a slime sample showed promise for a classification-flotation technique. Onsite classification tests at six phosphate washing plants were conducted with a two-stage hydro cyclone system designed to recover the plus 5-um material. The cyclone underflows contained 8.3 to 19.1 percent P2O5, and the recovery of the plus 5-um PZOS values ranged from 81 to 95 percent. The percent P2O5 recovery from the total slimes ranged from 38 to 47 percent. Batch-flotation studies are currently being conducted.

Jan 1, 1978

By Allan G. Provost

Shaft construction is assuming ever increasing importance when new mining enterprises are considered. The reasons for this increased emphasis is the much greater depths at which many new ore-bodies are being developed and the rapid depletion of near surface reserves requiring mines to go to greater depths on existing deposits. These greater depths increase the probability of exposure to unfavorable geologic conditions and it is more likely that high ground and/or water pressures will be experienced at these depths. The large capital costs involved and the critical position of a shaft in the overall mining program necessitate that this element of project development be given careful and critical consideration. The Henderson No. 2 Shaft is located in the Rocky Mountains of north central Colorado (See Figure I), about 55 miles west of Denver, near the community of Empire in Clear Creek County. At the 10, 442 foot collar elevation, winter arrives in late September and brings snow to contend with until May. The labor force for Shaft No. 2 is approximately 90 men. They are provided access to the project via all-weather U. S. Highway 40. SHAFT DESIGN The Henderson No. 2 Shaft is a 28-foot I. D. circular, concrete lined (1 foot thick) vertical shaft. The final depth will be approximately 3100 feet

Jan 1, 1972

By Nick Barton

The ability to estimate that support is unnecessary for various dimensions of opening in certain rock mass environments is of particular relevance in the mining industry, where most excavations are not expected to remain open indefinitely. As Hoek1 observes: "the basic aim of any underground excavation design should be to utilize the rock itself as the principal structural material, creating as little disturbance as possible during the excavation process and adding as little as possible in the way of concrete or steel support". Approximately two hundred case records have been analysed for the purpose of determining the amount of permanent support normally used when a given span is excavated in known rock mass conditions Some thirty cases concerned unsupported openings. Excavations that can stand unsupported appear to have certain common characteristics as regards rock mass quality. However, the mechanical properties of the rock mass are not the only factors controlling the choice of design. The dimension of the opening (span or height) and the type of excavation are two important variables.

Jan 1, 1975

By Michael G. Zabetakis

Effective accident prevention programs utilize a broad spectrum of activities, including meaningful training programs. In practice, such programs must be directed towards specific, defined needs. These needs are considered here for three categories of employees: new, re-assigned, and experienced.

Jan 1, 1983

By C. Dale Elifrits

Observations made from laboratory analysis of samples of fine-grained argillaceous materials (shales) subjected to various changes in moisture content have been correlated to loss of strength in the rock material. This reaction to a change in in-situ conditions (subsequent to mining) at a mine site combined with the observed relationships of surface-disturbing subsidence features at locations where the predominant overburden material is fine-grained, provides a predictive tool for the subsidence engineer.

Jan 1, 1983

By Barbara S. Parrish, I. S. Parrish

For two consecutive years the author and his wife have been fortunate enough to have been invited by the Peoples Republic of China to work with Chinese geologists of the Geological Bureau of the Ministry of Metallurgical Industries (MMI). Our visits, each of which lasted 7-8 weeks, took us to northwestern Sichuan, central Anhui, and much of Hebei Province, as shown in the accompanying drawing. We were asked to evaluate, criticize, and offer suggestions on the exploration and mining techniques used by the Chinese. Our commission both years was centered on gold, although we were also to visit other operations when the opportunity arose. In 1986, the visit primarily concerned with disseminated "Carlin" type gold deposits; in 1987, with "Greenstone" type gold deposits. Gold has been targeted by the Chinese as a metal of importance to the nation. Several governmental agencies have received direction and budgets to seek and develop gold properties. Besides the Ministry of Metallurgical Industry, gold is being sought by the Ministry of Geology, the China Gold Corporation, and reportedly the Peoples Army. There is considerable competition among these agencies. It is not uncommon to find two or more agencies working in the same general area. However, communication between the groups is minimal. Last year, we toured a small mine at Bambishan. We could see a diamond drill across the valley. The rig belonged to another Ministry and my guides voiced their curiosity to know what their competitors were finding. Mining, too, is not the monolithic bureaucracy that most Westerners anticipate in China. There are various levels of mining. These differ not only in sophistication, but in ownership. First, for small deposits the state allows "Peoples Mines". These can be owned and worked by individuals. The individual owner-miner may hire relatives or neighbors and give them a wage or he may turn the mine into a joint ownership situation. They

Jan 7, 1988

By Peter Schmäh, Tobias Engel

The E-Power Pipe technology was originally developed for the trenchless installation of protective pipes and pipelines of 10" to 28" diameter, over long distances of more than 4,000 ft. The twostage process combines elements from Horizontal Directional Drilling (HDD) and microtunnelling technology. A microtunnelling boring machine (MTBM) excavates the borehole using a specially designed, temporary jacking pipe. A Rack & Pinion jacking frame pushes the equipment during the pilot bore and pulls in the prefabricated pipe string in a second step. The slurry microtunnelling machine is equipped with a jet pump, creating the so-called AVNS machine type. A new generation of small hard rock cutting wheels complements this considerable achievement for the tunnelling industry

Dec 1, 2022

By Alafara A. Baba, Yakubu A. Dallatu, Kehinde I. Omoniyi, Shemang Y. Chindo, Edith B. Agbaji

As a result of the rise in global demand for pure copper, there is urgent need to consider the processing of low-grade chalcopyrite ores. Ammoniacal leaching solutions have been reported as an effective and efficient leachant for the dissolution of chalcopyrite. This work reports different parameters that influence the leaching kinetics of a Nigerian chalcopyrite-rich siderite ore obtained from Wase Local Government Area, Plateau State, Nigeria, and assayed as 11.30 wt% of Cu. At the optimum leaching conditions (0.4 mol/L NH3-( NH4)2SO4 leachant concentration; 75 °C reaction temperature; 45 μm particle size), the extent of chalcopyrite ore dissolution reached 87.4% within 120 min. The dissolution rate was affirmed to conform to the diffusion control mechanism with the activation energy, Ea, of 38.84 kJ/mol and a reaction order of 0.661 for the leachant concentration being established. The leaching mechanism was affirmed by characterizing the raw ore and the leached product by XRD and SEM-EDS analysis. Ascertaining optimal leaching conditions for copper using alkaline leachant is advantageous from the environment and economic points of view.

Jan 6, 2023

By Evan J. Owen, Virginia T. McLemore

There are tens of thousands of inactive mine features in 274 mining districts in New Mexico (including coal, uranium, metals, and industrial minerals districts). However, many of these mines have not been inventoried or prioritized for reclamation. Many of these mines have existing mine wastes, generated during mineral production, which could have potential for critical minerals, especially since the actual mineral production was generally for precious and base metals and not critical minerals. The purpose of this project is to characterize and estimate the critical mineral endowment of mine wastes and “beta-test” USGS sampling procedures. This project is important to the state of New Mexico because critical mineral resources must be identified before land exchanges, withdrawals or other land use decisions are made by government officials. Future mining of mine wastes that potentially contain critical minerals will directly benefit the economy of New Mexico. Possible re-mining of mine wastes could clean up these sites and pay for reclamation. Furthermore, this project will include training of younger, professional geologists and students in economic and reclamation geology by the PIs.

Feb 1, 2024

By Jason Swartz, Gerardo Gomez, Henry Leighton

San Antonio has experienced sustained growth for decades, putting increased pressure on existing wastewater infrastructure. In June 2013, San Antonio Water System (SAWS) reached a Consent Decree agreement that requires significant improvements to the wastewater system over a 10-year period to reduce Sanitary Sewer Overflows. One of the critical projects was the W-6 Upper Segment Tunnel project to reduce sanitary sewer overflows on an existing sewer main running through Lackland Airforce Base. The replacement project consisted of a new tunnel nearly 29,000 LF of primarily 104" FRP. The project also includes nine shafts and multiple trenchless crossings to make near surface connections to the new works.

Jun 23, 2024

By Jr. Moulton

Extractions of minerals from Searles Lake brines have taken place since 1873. Early operations were for borax and raw trona found on the surface, expanded after 1914 to include potash, salt cake, and soda ash. A new soda ash plant now in operation will double area production. The evaporite beds were formed by desiccation of Eastern Sierra runoff. The resulting series of brine-bearing salt beds supply the fluids necessary to feed the area chemical plants. Production methods include evaporation and crystallization for potash, borax, and salt cake; carbonation of brine to recover soda ash; and organic extraction of borax.

Jan 1, 1980

By Thomas Jancic

Two of the open-pit, copper-molybdenum mining operations of Duval Corporation are located in the foothills of the Sierrita Mountains approximately 30 miles southwest of Tucson, Arizona. In March 1959, mining from a moderate sized porphyry deposit known as the "Esperanza orebody" was begun at a rate of 10,000 tons of ore per day. Some five years later, a sizeable group of mineral claims west of Esperanza became available to Duval. Earlier exploration and development drilling in this area by others indicated an orebody of greater size but lower tenor than that of Esperanza. A drilling program conducted by Duval not only verified the results of the prior drilling but in addition, revealed a continuation of the mineralization to the south and east. Thus was developed the Sierrita orebody. Open pit design delineated 414 million tons of ore containing an average copper content of 0.35 percent and a molybdenum content of 0.036 percent. In April 1966, the office of Emergency Planning authorized General Services Administration to undertake a program under the Defense Production Act to en¬courage additional domestic production of copper in the interest of national defense. Duval's Sierrita Project was brought to GSA's attention in May 1966 on November 28, 1967, an agreement providing for the development of the Sierrita Property was consummated with GSA. In March 1970, the first copper-molybdenum concentrates were produced in the 72,000 tons-per-day concentrator. Pre-production stripping exceeded the scheduled 105 million tons despite the comparatively short lead time available to equip the mine, build the mine plant facilities, and staff the technical, supervisory, and labor forces. Shortly before the first concentrates were produced, plans were being formulated for a program to increase processing capacity by approximately 15 percent, which entailed increasing overall mining capacity by approximately 50,000 tons per day. This program is scheduled for completion early in 1971.

Jan 1, 1971

By HASAN SERKAN GOKCEN, SERKAN CAYIRLI

The purpose of this study was to investigate the dry grindability of calcite powders in a vertically and horizontally orientable laboratory batch type stirred mill. The experimental results were evaluated using stress intensity analysis. The performance was also compared in terms of mill orientation. The results showed that the d50 values decreased with increasing stress energy down to a certain point and then increased for both milling orientations. Even though the optimum stress energies for both vertical and horizontal orientations were in the range of 1*10−3 to 5*10−3 Nm at 750 and 1500 kJ/kg energy consumption, the product size was finer for the horizontal orientation at the same stress energy value. Additionally, to the best of the authors’ knowledge, this is the first study to compare mill orientation (vertical vs. horizontal) for the same mill and under the same test conditions.

Apr 21, 2021

By L. J. Altenburg

There are a lot of key factors involved in achieving a successful Safety Program. I would like to discuss some of these factors and how they have played a major part in our success at Jacobs Ranch Mine. The areas I will cover concern: 1) Facility Standards (Corporate/Minesite), 2) Communication (Employee/Management -"Teamwork"). 3) Proper Training (Employee/Management). 4) Employee Attitude. 5) Incentive Programs. 6) Health Programs. 7) Results/Benefits.

Jan 1, 1994

By Mark A. Krall

The Conda Partnership's Dry Valley Phosphate mine is a thinly bedded, multiple seam, open pit mining operation where selective mining techniques are used to recover phosphatic shales. The mining methods used are truck/shovel and scraper/ dozer operations. The ore that is mined is shipped 32 km (20 miles) by rail to a beneficiation facility which upgrades the ore via washing and calcining. The mine and beneficiation complexes are owned by the Conda Partnership. The Conda Partnership is a joint venture between Beker Industries Corp. of Greenwich, Connecticut, and Western Co-Operative Fertilizers (U.S.) Inc. of Alberta, Canada. The Conda Partnership operates as a separate entity from the two partners.

Jan 1, 1984

By Rick Wright, Gregory L. Raines

San Diego’s need to access underground space has dictated a long history of tunnel construction. The subsequent need for water, coupled with San Diego’s natural attractiveness, has led to significant population increases and the need for the construction of even more tunnels. This paper will provide a historical summary of the progression of mines, tunnels and trenchless technology construction projects that contributed to the advance of current technology, feasibility, and constructability. A bibliography of relevant reports and data is included.

Jan 1, 2001

By H. Lyn Bourne

This is the sixth annual tabulation that gives mineral royalty information. This tabulation, like the previous editions, includes all of the earlier data plus more than 100 new entries. In addition to the royalty information, some entries show the cost of purchased reserves. An article in the December 1984 Kentucky Coal Journal could have far reaching applications. It explains that a banking firm examined the "reserve risk" as one of six factors for analysis when financing a coal project. The firm concluded that coal reserves in Kentucky are worth an average of $0.29/t ($0.26 per st) in-place. The banking firm based this in-place value on its examination of more than 50 leases. In-place value is especially important when trying to establish a mineral value for a given deposit. Ernie Lehman wrote to this author after last year's column appeared and he quoted the lease rates for lead and zinc on federal land. He states, from first hand information, that the leases are based on a percentage of net smelter return as follows: 4% for the first five years, 4.5% for the next five years, and 5% thereafter. The figures used in last year's column ($ per st) came from dividing reported royalty income by reported production. The information reported last year merely translates the results of the net smelter return (as written in the lease) to royalty income per ton to the US Government for the various years. Statistics from the Minerals Management Service of the Federal Government show that oil and gas account for 40% and 53%, respectively, of the Federal royalty income. Coal accounts for about 4% and all other minerals, the remaining 3%. Oil and gas leases are mostly at 12.5%. Most of the coal leases are at 12.5% for surface mining operations and 8% for underground mining. Many of the other commodities are leased at 5%, which has been true for decades. Relative to Federal leases, this year's table shows some percentages and some costs per ton. This was done to give information about the leases and also to show income produced by various commodities. Note that some commodities have a variation in $/ton even though the royalty percent is the same. These variations result from a combination of factors that influence the value of a mineral commodity. The same caveats that have appeared in previous columns relative to factors that influence the value of reserves are restated. The data in the table serve as a general reference and are not intended to present an absolute scale of reserves costs. Several factors influence the value of any mineral commodity. The factors include: • location/transportation (especially significant for most industrial minerals); • market conditions both for the commodity and the company acquiring the right to mine it; *quality or grade of the deposit as it reflects the amount of processing/beneficiation necessary to produce the finished product; and • legislative restrictions and conditions for mining a given material at a given site. These and other factors will significantly influence the cost of reserves. The table shows the range of royalties and the variations in the basis of computing the fees. In a few instances, it gives the cost of acquired reserves based on purchase price and quantitative estimates of the material in place. The table lists the commodity in column 1, and the subsequent columns give the location - either by state, US geographic area or Canadian province; the cost - R for royalty and P for purchased cost; and the year in which the lease or purchase agreement occurred. The last column offers either comments or gives a footnote number for more information. The cost column requires more explanation. The units may refer to cubic yards (/yd), cubic feet (/cu ft), tons (/T, 2000 lbs) or acres (/A). 1 cu yd = 0.7646 m3 1 cu ft = 0.2832 m3 1st=0.9078t 1 acre = 0.4047 hm or m2 In several cases, the royalty is a percentage of the sales price of the finished product and is levied against either the amount produced or the amount sold. We thank those who contributed information for the table: G. Anderson, B. Brown, R. Ganis, K. Hauser, E. Lehman, and S. Sims. Their help is appreciated as are the contributions by those who asked to remain anonymous. This column requires additional information each year. That data must come from people in the minerals industry who have royalty information. What appears in the table is only a very small fraction of the cost information relative to the various commodities and the geographic areas for which there is royalty information. If you find this column of interest and possess information write the author at the address given in the author's box or call 313-462-0005.

Jan 7, 1988

By Huijun Shao, Qiang Liu, Zhengming Yi

The increase of the proportion of high Al2O3 content iron ore fine in iron and steel enterprises has brought about a series of problems such as the increase of the viscosity of blast furnace slag and the difficulty of the separation of slag and iron. In order to solve this problem, the effect of increasing MgO content on the technical and economic index, the cold strength, and metallurgical properties of high basicity and high-alumina sinter was studied through sinter pot test. Nova400NanoSEM field emission scanning electron microscope was used to analyze sinter microstructure. The experimental results show that when the MgO content fraction in the sinter with high basicity and high aluminum increases from 1.72 to 2.49%, the vertical sintering speed decreases by 4.38mm/min, the utilization coefficient decreases by 0.51t/(m2 h), and the low-temperature reduction degradation index increases by 6.7%. When MgO content in sinter is 2.11%, drum index and reducibility index are the highest, reaching 61.93% and 86.39% respectively. Mg2+ is mainly solid dissolved in the magnetite lattice and replaces Fe2+, up to 3.64%. The generated magnesie-containing magnetite inhibits the phase transition from Fe3O4 to Fe2O3 oxidation process in the sinter cooling process, which reduces the generation of secondary hematite and is conducive to improving the low-temperature reduction degradation performance of sinter.

Jul 4, 2021