Search Documents

By John J. Reed

Since the beginnings of, the human struggle for survival and improvement, mining has been one of the basic endeavors of life. Until relatively recent times it was classed as an art. Now we are at work trying to, raise mining to the level of an engineering science where it belongs if we are to prosper. It should be self-evident that this goal can be attained only through industrial progress: based on education and research. It is true that our industry, left to itself, will develop a few new ideas and techniques through the years. However, we mining' engineers are relatively few in number compared to the other disciplines, and the rate of our improvement by such "accidental" discoveries is simply tooslow to keep pace with the rest of our technical civilization. It will be evident in the remarks that follow, that the rapid development of mining education, research, and the industry are extremely interdependent, and will be largely controlled by the amount of cooperation, support, and cross-fertilization that can be developed among all three.

Jan 1, 1961

By John C. Schneider

In the mid 60's Prochem & Hydrochem Development, it's research division, developed the high efficiency Maxflo impeller. Since the Maxflo impeller had a design that had proven to be very efficient in gas-liquid-solid contacting, it was a natural extension to apply this design to flotation & the research commenced in the mid 80's. An opportunity to test the energy savings occurred at Dickenson Mines in 1987, & comparative results with existing conventional flotation cells showed a marked increase in capacity, grade & recovery with 25% less power applied. This r success was followed by the installation of the fist agitated Flotation Colunm (5ft. dia. x 25ft. tall). As a result of the Dickenson success, Hydrochem started a comprehensive 2-part research program in 1988. At Randol Gold Forum 1988 a paper by Hydrochem was pre

Jan 1, 2000

By Alex Joseph

A tertiary amine containing polyamine in its back bone was grafted to exfoliated graphite oxide by means of a series of chemical reactions.The synthesized amine functionalized polyaniline grafted to exfoliated graphite oxide (EGAMPANI) was characterized using various techniques such as, FTIR, TGA, Raman, and X-Ray diffraction.The synthesized EGAMPANI was blended with carbon paste electrode, and used to study the response of Hg2+ in acetate buffer solution.Preliminary analysis showed that the anodic current intensity using the EGAMPANI modified electrode was higher during a potential sweep and 10-4 M concentration of mercury could be detected which could be improved to 10-6 M using anodic stripping voltammetric technique. Keywords: metal sensor, exfoliated graphite oxide, functionalization, polyaniline

Sep 1, 2012

By G. J. G. Juby

The Chamber of Mines Research Organization has been evaluating three membrane-desalination processes for use within the South African mining industry. These processes are electrodialysis reversal (EDR), tubular reverse osmosis (IRO), and slurry precipitation and recycle reverse osmosis (SPARRO). The evaluation of EDR and TRO is complete, and the operating costs (1988) associated with each process are expected to be about 50 cents per kilolitre for a plant of 50 l/s (4 Ml/d) installed capacity. The SPARRO process is still being evaluated. Pilot plant results, water Qualities, and expected capital costs are presented where appropriate.

Jan 1, 1992

By C. Braun, C. Kennedy, P. Katsabanis

A series of small scale tests, simulating multi-hole blasts have been performed to establish the effect of delays on blast fragmentation. The blasts were performed in high quality granodiorite blocks, which were cut from stone prepared by dimensional stone quarry operations. The pattern used was equilateral triangular, with a distance of 10.2cm between boreholes, which had a diameter of 11mm, were loaded with detonating cord and the coupling medium was water. The delays used were achieved using different lengths of detonating cord for the cases of delays between 0 and 100 microseconds between holes and a sequential blasting machine firing seismic detonators for larger delays up to 4ms. All fragments were collected and screened. The experiments showed that the coarsest fragmentation was achieved with simultaneous initiation of all charges. Fragmentation became finer with delay time between holes up to 1ms between holes. The results show that in moderate to competent rock, similar to the granodiorite of the experiments, fragmentation optimization requires delays of few milliseconds per meter of burden. In view of the findings, which agree with previous published work, the current trend of selecting fast firing times for fragmentation optimization is questioned.

Jan 1, 2006

* The greatest and richest iron ore body in the world was discovered by U. S. Steel in Venezuela in April 1947, and is disclosed for the first time in this issue (p. 178), One solid mountain of ore, Cerro Bolivar, will furnish more tonnage than the famous Hull Rust pit at Superior has, or can produce. Total resources are on the order of 2 billion tons plus. Big Steel is now moving with great speed on construction to bring out this ore, and 10 million tons are scheduled for shipment into Baltimore and Birmingham by late 1952. This ore will arrive at, Pittsburgh at a price lower than present natural ores from Superior. The Venezuelan properties will be completely mechanized. •U. S. Steel and independent companies are embarking on a taconite beneficiation program of tremendous proportions, which must be speeded to completion in the 1950's (see p. 185). By 1960 over $l.2 billion dollars will be spent on Venezuela, taconite, and Labrador to solve the United States iron ore crisis. In addition, U. S. Steel will spend another $300 million plus for a new steel mill at Trenton, N. J., before 1955. •The Deister Concentrator Co. gave $500 to the 1950 Coal Division Scholarship Fund. •Howard N. Eavenson, in analyzing the bituminous coal situation (see p. 193), suggests that anti-trust laws be extended to labor unions, disinterested trustees to administer pension funds, begin pension funds now and stop the collection of all "check-offs" for union dues or funds. •Minerals and metals worth 13.9 million dollars were produced in the United States in 1949, Secretary of the Interior Oscar L. Chapman announced. Although this value was 11 pct less than in 1948, it was the second greatest in history. Nonmetallics was the only major group that in 1949 equaled the 1948 production high. Mineral fuels decreased 12 pct and metals 15 pct. • Prospects for making gas from coal are seen to be unattractive by the Pittsburgh Consolidated Coal Co. because the success of operation depends on price and supply of coal which presently are not attractive. The company has shut down its gasification plant at Library, Pa. * Economic prospects for the immediate future in the United States are good and business probably will continue at its present high levels throughout at least the early part of 1950, Secretary of Commerce Charles Sawyer said in his year-end report to the White House based on his personal survey of business conditions. •A 467-ft well 34 miles north of Rock Springs, Southwestern Wyoming, is said to be flowing a 5 pct solution of nearly pure trona (sodium carbonate) at the rate of 10,000 barrels a day. Trona, natural soda ash, is mined for the chemical trade at Searles Lake, Calif., and from about 1500 ft underground near Green River, Wyo., and has been in short supply. •The AEC is "very much interested" in a discovery of radioactive material that has been made in Baraga County bordering Lake Superior in the Upper Peninsula of Michigan, reported F. G. Pardee, Michigan State mining engineer. The material has been identified as uranium oxide in the form of pitchblende or uraninite. The discovery, made by a geologist of the Jones & Laughlin Ore Co., is the only instance in which the commission has certified samples of Michigan rock.

Jan 2, 1950

By Michele L. Kimble

A fast-flow reactor mass spectrometer has been utilized to investigate the reactions of gas-phase gold cluster anions with CO and oxygen. Addition of CO to Aun - produces species of the form Au(CO)m -, where m = 2-5. However, CO does not bind to Au2 - or Au3 -. With oxygen addition in the cluster source, gold oxide species with both molecular and atomized oxygen are produced. The addition of carbon monoxide to these preoxidized gold cluster anions reveals that select species with 1, 2, and 3 gold atoms participate in the oxidation reaction to produce CO2. Bimolecular rate constants for the reactions between these species and CO are also discussed.

Oct 1, 2003

By B. Wasmund, B. Haneman, G. Sheehan

Success in implementing new technology for metallurgical processes is not a foregone conclusion: This paper includes a survey of 23 new technology-based metallurgical plant start-ups, in which the authors have identified 7 successes, 9 difficult start-ups, and 7 failures. Success is defined not only as meeting the schedule and budget to the end of mechanical completion; the key goal is a fast ramp up to the full design production level, with minimum plant and equipment modifications required after start-up. This paper sets out the key factors that underlie achievement of a quick production ramp up curve, as determined from the authors' project experiences and a quantitative analysis of over twenty metallurgical plant start-ups, both pyrometallurgical and hydrometallurgical. Thorough test-work and pilot plants, plus appropriate scale-up to the full commercial plant, are key determinants of success in implementing new technology in metallurgical processes. Another critical factor is the number of new elements and their interactions. Project phasing is also particularly important for new technology projects, with appropriate review after each phase to develop a risk mitigation plan for the subsequent phase. New technology projects need committed champions to advance the project in the face of sceptics, but also require dispassionate and unbiased experts to ask the hard questions. As a project evolves, it is important to periodically question the appropriateness of assumptions, as well as to re-assess the relevance and completeness of data from test-work I pilot plants I industrial analogues. Sufficient human and financial resources are required to complete the often arduous implementation phase. During the ramp-up period, the operation generates little positive cash flow; however, significant expertise and capital are required for the de-bottlenecking projects that are often necessary to reach the plant's design output level.

Jan 1, 2011

By Pierre Antoine Dhaiti, Gilbert Sergerie, Michel Dagbert, Jean-Maurice Brodeur

"Quality of iron ore is generally determined by several factors which can be correlated or independent. Among these f actors, we generally find per cent iron, silica, magnetite or hardness. Forecasting the short- and long-term fluctuations of these f actors in the future pit is an important feature of mine planning in these deposits. Computer simulation provides a realistic answer to these questions. It allows to generate values for the most important quality features of each shovel load with the proper correlations between them as well as between one load and the next being fully reproduced. Then different sampling schemes f or grade control or blending facilities can be examined on the simulated data. The mechanics of the simulation procedure and its potential applications are described in an example.IntroductionThe purpose of this paper is to illustrate the use of in-situ grade simulation in the planning o f the grade control in an iron ore min e. More precisely, given a production unit of given size, we need to know how many samples have to be collected in that unit so that we ca n recognize its grade with a reasonable precision. Conclusions that we would like to arrive at are of the type: with 4 blasthole samples we ca n get the iron grade of a 10,000 ton bloc k with less than a ± 2% Fe error 95% of the time.The approach t hat we take to solve this problem is simulation. We simulate the grade of samples and the grade of the block that contains these samples. We repeat the simulation for hundred s o f blocks. By comparing the sample grade with the block grade in each case, we determine the actual number o f blocks where the difference sample-bloc k is less than a given limit."

Jan 1, 1983

By C. L. Jiang

The role of iron ions (Fe2+ and Fe3+) in the flotation of both ore-and coal-pyrite with ethyl xanthate was comparatively investigated. The complete/partial depression of ore-and coal-pyrite in neutral to weakly alkaline solution is due to the formation of ferric dihydroxy ethyl xanthate between xanthate and the oxidation products of pyrite, ferric and ferrous ions. With xanthate as collector, coal-pyrite was found to be nonfloatable above pH6. In the presence of iron ions and between pH6-9.5, the flotation of ore-pyrite was significantly depressed. Ferrous ions have a stronger effect on pyrite flotation than ferric ions in neutral to weakly alkaline solutions.

Jan 1, 1996

By William D. Klopp, Joseph R. Stephens

A substantial reduction in the 300°F ductile-to-brittle transition temperature for unalloyed chromium was achieved in alloys from systems which resemble the Cr-Re system. These alloy systems include Cr-Ru, Cr-Co, and Cr-Fe. Transition temperatures ranged from -300° F for Cr-35 at. pct Re to -75°F for 0-50 at. pct Fe. The ductile alloys have high grain gvowth rates at elevated temperatures. Also, Cr-24 at. pct Ru exhibited enhanced tensile ductility at elevated temperatures, characteristic of superplas-ticity. It is concluded that phase relations play an importarlt role in the rhenium ductilizing effect. The ductile alloys have compositions near the solubility limit in systems with a high terminal solubility and which contain an intermediate o phase. The importance of enhanced high-temperature ductility to the rhenium ductilizing effect is not well understood although both may have common basic features. CHROMIUM alloys are currently being investigated for advanced air-breathing engine applications, primarily as turbine buckets and/or stator vanes. The inherent advantages of chromium as a high-temperature structural material are well-known1 and include its high melting point relative to superalloys, moderately high modulus of elasticity, low density, good thermal shock resistance, and superior oxidation resistance as compared to the other refractory metals. Additionally, it is capable of being strengthened by conventional alloying techniques. The major disadvantage of chromium is its poor ductility at ambient temperatures, a problem which it shares with the other two Group VI-A metals, molybdenum and tungsten. For chromium, the problem is further amplified by its susceptibility to nitrogen em-brittlement during high-temperature air exposure. In cases of severe nitrogen embrittlement, the ductile-to-brittle transition temperature might exceed the steady-state operating temperature of the component. The low ductility of chromium would make stator vanes and turbine buckets prone to foreign object damage. The present work was directed towards improvement of the ductility of chromium through alloying, with the anticipation that any improvements so obtained might be additive to strengthening improvements achieved through different types of alloying. The alloying additions for ductility were selected on the basis of the similarity of their phase relations with chromium to that of Cr-Re. The reduction in the ductile-to-brittle transition temperatures of the Group VI-A metals as a result of alloying with 25 to 35 pct Re is well established.a4 the temperature range -300" to 750° F. This phenomenon is commonly referred to as the &apos;<rhenium ductilizing effect"; this term is also used to describe systems in which the ductilizing element is not rhenium. Other alloy systems which have recently been shown to exhibit the rhenium ductilizing effect include Cr-Co and c-Ru.= In order to explore the generality of this effect, alloys were selected from systems having phase relations similar to that of Cr-Re, primarily a high solubility in chromium and an intermediate o phase. The following compositions were prepared: Cr-35 and -40Re; Cr-10, -15, -18, -21, -24, and -27 pct Ru; Cr-25 and -30 pct Co; Cr-30, -40, and -50 pct Fe; Cr-45, -55, and -65 pct Mn. Seven other systems were also studied which partially resemble Cr-Re. These systems have extensive chromium solid solutions or a complex intermediate phase, not necessarily o. The compositions evaluated include the following: Cr-20 pct Ti; Cr-15, -30, and -45 pct V; Cr-2.5 pct Cb; Cr-2.5 pct Ta; Cr-20 pct Ni; Cr-6, -9, -12, and -15 pct 0s; Cr-10 pct Ir. The compositions of alloys in these systems were chosen near the solubility limit for the chromium-base solid solutions, since in the Group VI-A Re systems, the saturated alloys are the most ductile. These alloys were evaluated on the basis of hardness, fabricability, and ductile-to-brittle transition temperatures. In addition to the studies of alloying effects on ductility, an exploratory investigation was conducted on mechanical properties at high temperatures in Cr-Ru alloys EXPERIMENTAL PROCEDURE High-purity chromium prepared by the iodide deposition process was employed for all studies. An analysis of this chromium is given in Table I. Alloying elements were obtained in the following forms: Commercially pure powder — iridium, osmium, rhenium, and ruthenium. Arc-melted ingot — titanium and vanadium. Electrolytic flake — iron, manganese, and nickel. Sheet rolled from electron-bearn-melted ingot — columbium and tantalum. Electron-beam-melted ingot — cobalt. Sheet rolled from arc-melted ingot — rhenium. All alloys were initially consolidated by triple arc melting into 60-g button ingots on a water-cooled hearth using a nonconsumable tungsten electrode. The melting atmosphere was Ti-gettered Ar at a pressure of 20 torr. The ingots were drop cast into rectangular slabs and fabricated by heating at 1470" to 2800° F in argon followed by rolling in air. Bend specimens measuring 0.3 by 0.9 in. were cut from the 0.035-in. sheet parallel to the rolling direction. The specimens were annealed for 1 hr in argon, furnace cooled or water quenched, and electropolished prior to testing. Three-point loading bend tests were conducted at a crosshead speed of l-in. per min over

Jan 1, 1969

By E Topal

Stopes are used in several underground mining methods. Boundary determination of these stopes is generally based on simple rules of thumb. While several stope boundary optimisation techniques are available, they fail to guarantee true optimum results. The first part of this paper reviews some important stope boundary optimisation studies and proposes a new algorithm to optimise stope boundaries and layouts for underground operations. The second part applies the proposed algorithm to a block model to test its ability to produce optimum results and demonstrate its applicability in a number of different scenarios. The results demonstrate that the proposed algorithm can find optimum stope boundaries and layouts in three dimensions for different stope sizes and economic conditions.

Jan 1, 2009

By AIME AIME

L. C. GRATON, professor of geology in Harvard University, addressed the New York Section on April 24 on-his impressions of the Rand. His beautifully clear and concise address was delivered without notes, so that what follows is merely a resume of the principal points made. The world is apparently coming to the end of ore discoveries easily made, yet we need metals at a steadily increasing rate. If surface discoveries are to decline, then we must find other ores or use less metals. The probable chances of finding ore are greater in the centers of big production than in new districts, as proved statistically. It is unsafe to say that a field is worked out. Therefore, deep mining holds possibilities and is an interesting study that will progressively gain in importance. The origin of the gold in the banket of the Rand has been a geologic football for a long time. Of the various theories, two have survived: 1. Infiltration into permeable conglomerate beds from deep-seated sources; 2. the placer hypothesis, which holds that gravel beds originally had the gold in them. At present, the second theory is accepted by the majority, as a result of the studies by the Union Geological Survey and by E: F. Mellor which were published about fifteen years ago.

Jan 1, 1929

By M. T. McDonough

THE data relative to the effect of metal depth on slag volume was obtained from the operation on two acid electric furnaces in which heats of various sizes were produced. The furnaces used were of 3 and 5-ton rated capacity; the heats investigated ranged from 6 to 8 tons. Heats of 7 and 8 tons were made in the larger furnace; heats of 6 tons in the smaller one. Bath depths and diameters were measured on the furnaces when cold and each is accurate to one inch. Both the metal charge and the slag were weighed on a track scale accurate to ± 25 lb. All other components added to the furnace were weighed on a wheelbarrow scale accurate to ±5 lb.

Jan 1, 1947

By R. W. Snyder, H. J. Ramey

This paper presents the results of applying the Buckley-Leverett&apos; displacement theory to petroleum reservoirs consisting of a finite number of layers. The layers are assumed to communicate only in the wellbores, and the reservoir may be represented as a linear system. Most previous investigations of this nature were limited by assumptions and by inconsistent calculation techniques. This study improves on previous work by applying the Buckley-Lev-erett displacement theory to a noncommunicating layered system where permeability, porosity, initial saturation, residual saturation and relative permeability vary from layer to layer in a logical and consistent manner. Gravity and capillary-pressure effects are neglected. A modification of the Higgins-Leighton calculation method was used in this study. Waterflood predictions were made with all properties varying, and then with only permeability varying using several inability ratios. These results were compared with the Stiles and Dykstra-Parsons predictions. It is shown that the latter methods generally give poor values for the breakthrough recovery and pessimistic predictions for the performance after breakthrough. Similar results were obtained for a gas-displacement case. lNTRODUCTION Field experience with immiscible displacement usually shows constant producing conditions until breakthrough of the displacing fluid. Then oil production continues at increasing displacing-to-displaced fluid ratios until the economic limit is reached. Three different ideal mechanisms are known that will produce this behavior: (1) relative permeability effects as described by Buckley-Leverett frontal advance theory,&apos; (2) vertical stratification as considered by Stiles,2 Dykstra and Parsons5 and others and (3) different path lengths involved in areal (two-dimensional) flow between wells as described by Dyes et al.4 Without question, a combination of these factors modified by formation heterogeneity and other known and unknown factors actually does control the behavior of real systems. This paper presents results of an investigation of certain factors that should affect performance but which have received little attention to date. In 1944, Law5 demonstrated that porosity and perme- ability are often found to have normal and logarithmic-normal distributions, respectively. throughout cored intervals in natural formations. This led to the concept of the noncommunicating, multilayered reservoir model for immiscible displacement. This model assumes that the reservoir is composed of a number of layers that communicate only at the wellbores. Each layer is individually homogeneous, but may be different from every other layer. Stiles&apos; presented one of the earliest applications of this model to waterflood performance. In addition, Stiles assumed that the initial saturations and relative permeabilities were the same for each layer, porosity was the same. displacement was piston-like, fluids were incompressible and injection into each layer was proportional to that layer&apos;s permeability capacity (permeability-thickness product). The last assumption would be true if the mobility ratio for the displacement were unity.21 Dykstra and Parsons" used the same model as Stiles, but rigorously included mobility ratios other than unity for piston-like displacement. Dykstra and Parsons used their general result to produce charts for log-normal permeability distributions between layers. Similarly, Muskat6 Pub1ished analytical solutions for linear and exponential permeability distributions. In 1959, Roberts&apos; described a scheme for calculating water-drive performance for the noncommunicating, layered reservoir model which considered two-phase flow in the displaced region. Roberts used the same model and assumed that the injection rate into a layer was proportional to that layer&apos;s permeability capacity, but that flood front locations could be evaluated from the Dykstra-Parsons results. These assumptions are inconsistent, and a material balance cannot be maintained except for a mobility ratio of unity. At the same time, Kufus and Lynch8 coupled Buckley-Leverett displacement theory with the layered model to provide an improvement of the Dykstra-Parsons method that was consistent. In 1960, Higgins and Leighton9 resented a numerical method for calculating waterflood performance also considering two-phase flow in the displaced region. The result was used to investigate variation in absolute permeability and oil viscosity. An excellent, detailed history of using the noncomrnunicating, layered reservoir model was presented by Nielsen.&apos;" The preceding techniques (and many related ones) were similar in that differences in initial saturations, residual saturations and relative permeabilities from layer to layer were neglected. It is well known that the irreducible water saturation is an important function of absolute permeability. Calhoun11 showed that the irreducible water saturation

By Gustavo Menezes Nevesr

Este trabalho tem como objetivo apresentar os resultados do procedimento de adequação do sistema de geração de vapor na CTE-1, visando à redução de custo no grupo CSN. O estudo foi efetuado através da avaliação das condições operacionais dos equipamentos e análise dos processos de geração de energéticos da planta CTE-1, aos quais permitiram diagnosticar as melhores práticas e definir a melhor configuração. Os resultados apresentados foram significativos para as condições de operação atual, o que representa redução do custo para o grupo CSN. Com redução do consumo de vapor e energia.

Sep 25, 2017

Mill #4 processes mildly refractory ore from Carlin Trend deposits. Diagnostic analysis of plant operating data was used to generate a mathematical model containing the important parameters influencing gold recovery. The model was used to direct modifications to plant operating practice. The cyanide-dosing strategy was changed to reduce gold losses from preg-robbing and to cut reagent consumption. A finer grind was achieved without capital investment. The density in the carbon-in-leach circuit was lowered, and tighter control was exercised over the plant throughput. These changes resulted in a recovery increase of at least 2%, worth $111,000/month at $300/oz ($9.64/g) gold, and concomitant reagent cost savings of $55,000/ month.

Jan 1, 2000

1. Healthy and active Local Section organizations are vital factors in promoting the vigor and growth of the Institute. 2. Activity on the part of Local Sections should be recognized and stimulated by appropriation of funds from the Institute&apos;s treasury; and these appropriations should be as large as is consistent with the relative needs for other activities. 3. As between different Sections, the amount of such appropriations should be based primarily on the extent of activities as reflected in the number and character of meetings held and the attendance of the members at such meetings. 4. In making a request for funds for any year, the officers of a Local Section should submit a report on the printed form approved by the Directors at their meeting on November 19, 1937. 5. A standing Committee on Local Section Appropriations, consisting of one past Chairman of a Local Section, one member of the Institute&apos;s Executive Committee, and one member of the Finance Committee, shall be appointed by the President and shall pass upon requests for appropriations and authorize payments within bounds of the budget. The committee will be guided by the principles herein outlined, always having in mind the vital importance of healthy, active Sections to the welfare of the Institute as a whole. 6: According to Article XI, Section 2 of the Bylaws, requests for appropriations shall be signed by the Chairman, Secretary and Treasurer of the Section. 7. Requests for appropriations must be in the hands of the Secretary of the Institute by February 15 of the year for which they are desired.

Jan 1, 1946

Readers of recent Bulletins have doubtless observed that the problem of improving both material and moral condition of employees is receiving close attention from influential members of the Institute. This will lend interest to certain developments and investigations that have been reported elsewhere.

Jan 5, 1918

By John W. Rushton

THE PLANNED MAINTENANCE PROGRAM All concentrators should start with a planned maintenance program from day one. Every- body thinks they have a program in place before start-up, but in reality, most have only a fraction of what is needed to avoid the "Post Start-up Disaster" (PSD) - two years for start-up is not that uncommon. An effective program has all of the following: (1) Good people. (2) Area Maintenance. (3) Good PM Checklists. (4) Daily Work Schedules. (5) Written Work Orders. (6) Equipment Histories. (7) Backlog Control. The installation of a workable program takes hard work, talent, and commitment. You have to know what you are doing (hard work will not replace talent). Good People Good people are available in any location if you make the effort. Always check references carefully (both superiors, peers and subordinates). Was the last concentrator they worked at successful? Was it clean? Find out! Success or failure follows people around. I know people who are experts on PSD because they have lived through it three or four times. You need some college trained people with hands-on experience. There are no secrets, you have to make the effort. If you make a mistake in hiring (and you probably will), make the tough decision necessary to rectify it quickly. Area Maintenance Area maintenance refers to organization of supervision such that one person is uniquely accountable for every inch of ground and piece of equipment. Avoid overlapping authority if at all possible. You must have a planner as a staff position. A foreman cannot effectively plan and

Jan 1, 1986