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By H. S. Auvil

[The shrinkage of coke after formation is one of the variables that effects the net expansion of the change in both industrial and test ovens. Various test results5/ have been interpreted as indicating that cokes from certain coals shrink to a marked extent and that other cokes show very little shrinkage; but no comprehensive experimental study of the shrinkage of coke after its formation and of the factors influencing this shrinkage has come to the attention of the authors.]

Jan 1, 1940

By V. M. Shick

For practical purposes of the use of information resources in the field of geomechanics and mine surveying with accepted mining technology in mines, the authors have developed the packaged software programs of the survey-geomechanical information system with database objects of mine field. This system enables to execute the graphical representation of workings layout in preset scale, axonometric projection, the zones of higher ground pressure: program packages for calculations of rock pressure manifestations and for selection of suitable support facilities for the permanent, development and active workings and vertical shafts based on the information resources of the State Research Institute of Mining Geomechanics & Mine Surveying (VNIMI). The program packages are applied at coal mines in Russia and in Kazakhstan. The profitable operation of coal mines can be reached only by the combined optimal engineering decisions in mine working's laying-out and their reliability and safety at the stages of their designing and exploitation, and with minimal harm of the environment as well. This problem is being complicated by the fact that today the mining-practicing engineers and designers are ordinarily facing the problem " of an information barrier", when the complexity of controlling systems exceeds the potentialities of traditional management of production practice. Coal mine is a typical representative of complicated systems, because the information about geological structure, physicomechanical properties and stress-strain state of rock mass are of fragmentary character and insufficiently reliable. A mine has a developed network of interrelated workings, by the way, some of them are productive ones being subjected to control to a certain extent, and some of them are abandoned ones being noncontrollable and hazardous in rushes of water, gas, pulp and fire. The ground pressure forces cause the disintegration of rock mass growing with depth. The progress of mining operations constantly changes the geomechanical situation forming the zones of bearing pressure, stress relieving, coal falling, as well as it leads to the pulp movement on the earth surface, breaks the ground water flow, causes deformations and changes in stability of buildings, constructions and natural objects on the earth surface. One should take into account the existence of hazardous zones within the mine field, i.e. the zones of elevated ground pressure, geological dislocations and those ones under natural water reservoirs, ponds, etc. Major coal seams are prone to rock bursts, sudden outbursts, bleeding, endogenic fire. It is obvious, that in practice it is extremely difficult to account for the mentioned above factors in their interrelation.

Jan 1, 1996

By Cuppam Dasarathy

The incidence of liquid inzmiscibility in binar)) indium alloys has been theoretically analyzed on the basis of the Hildebrand-Alott equation. Bedictions of miscibility or otherwise Imve in general been found to agree with those phase diagrams that are already publislzed in the literature. Out of a total of 27 systems, where either the complete phase diagrams are published or liquid immiscible behavior is reported, the Predictions agree with the experimental data in 25 systems, the exceptions being the Te-In and Ni-In systems. According to the equation, liquid immiscibility is also indicated in the binary alloys of indium with K, Rb, Cs, Na, Sr, Ba, Ti, Zr, V. Nb(Cb), Ta, W, U, Re, Ru, Rh, Os, and Ir. RECENT investigations by the author have shown that indium when alloyed with iron, chromium, and cobalt shows liquid immiscible behavior.1"3 The Fe-In phase diagram shows a wide range of compositions where the liquids are immiscible.4,5 No intermediate phases are present in this system. No precise information is available about the extent of liquid immiscibility in the Co-In system. However, it is certain that there is a range of compositions where the liquids are immiscible and that there are two or three intermediate phases,376 in the system. Liquid immiscibility is also strongly indicated in the Cr-In system and no evidence was obtained in the brief investigation to indicate the presence of intermediate Cr-In phases.2 The present paper deals with a theoretical analysis of binary alloys of indium with certain elements of the periodic table and indicates the systems where liquid immiscibility may be expected. The incidence of liquid immiscibility in binary systems has been theoretically examined by many workers and many excellent papers are available on the subject. In this paper, the alloy systems are examined on the basis of the more recent ideas proposed by Mott.7,8 It has been claimed8 that the Mott parameter predicts the incidence of miscibility or otherwise with reasonable accuracy and consistency. BACKGROUND TO MOTT&apos;S APPROACH Hildebrand applied his immiscibility rule for non-polar liquids to various alloy systems.9 The basis of this rule is that the equation for the excess free energy of formation of a liquid solution is rather similar to the theoretical expression for the energy of mixing of a regular solution. He postulated that when the heat of mixing is sufficiently high, separation into liquid phases will occur and the condition for complete CUPPAM DASARATHY is at the Research Centre, British Steel Corporation, (South Wales Group), Port Talbot, Glamorgan, Great Britain. Manuscript submitted March 12, 1969. IMD miscibility was shown as where VA and VB were the atomic volumes of the components A and B, and ?EV the energy of vaporization of the component. The term (?EVA/VA)1/2 was regarded as a measure of the binding energy of the component A and was called the L&apos;solubility parameter" 8A. On this basis immiscibility occurs when 1/2(VA+VB)(bA-bBf > 2RT [2] Apparently, however, there were several inconsistencies in that according to Eq. [2] several systems known to be miscible in the liquid state were predicted as immiscible. MOTT&apos;S ANALYSIS ~ott&apos;" regards that the reason for the inconsistencies arising out of Hildebrand&apos;s equation was largely due to the electrochemical attraction between the two elements, not being considered. Hence, Eqs. [I] and [2] were modified by taking into account the electro-negativities of the two elements XA and XB, and Mott arrived at an equation for immiscibility, i(VA + VB)(6A - aB)2 - 23,Q60n(XA - XBf > 2RT [3j which can be written as i **&£*&* >&apos;*°™- &apos;• HI T being the melting point of the more refractory component of the system. In Eq. [4], the numerator was called the Hildebrand term, the denominator, the electronegativity term, and their ratio, the Mott number. Mott observed that if the Mott number of a given binary system was greater than the maximum number of Pauling bonds which the two metals could form, then liquid immiscibility could be expected. The maximum number of bonds formed by a given metal was considered to be directly related to the number of bonding electrons available, i.e., to its maximum valency. Since the valencies of the elements considered vary from 1 to 6, Mott assumed that if the ratio of the Hildebrand term to the electronegativity term was >6, then immiscibility could be expected. On the contrary, if the ratio is <1, the metals should be miscible. Further, the alloying behavior is not only influenced by the valencies of the two elements but also by the relative atomic sizes that influence the types of packing and hence the coordination number. Mott considers that on average the maximum number of near neighbors of unlike atoms is 6. Thus, on both valency and size factor considerations, Mott concludes that the maximum number of bonds&apos; possible in any system was 6, this being the upper limit of the Mott number for miscibility. In considering the alloying behavior of systems with Mott numbers between 1 and 6, Mott plotted the num-

Jan 1, 1970

THERE are certain facts that the mining industry in Australia is faced with at the present moment which may be accepted as axioms. The industry is at a low ebb, as evidenced by statistics. Metals form the basis of all modern industries, and are necessaryfor the welfare of Australia. Mining is a wasting asset. Every ton of ore extracted is one ton less which c.annot be made good, and it should be our duty to get as much profit froin that ore as possible, otherwise there is a permanent loss to the country.The metal market cannot be controlled by Australia; it is more or less an international matter. Australia has not been thoroughly prospected. There are no mines being developed that are likely to replace those which are being depleted.Our mining engineers are as capable as those in other parts of the world, and have made good where they have been given a chance. There is no one cause for the present depression; there are several, more or less, interwoven. Of course, the war has had an adverse effect, but that has only dislocated things temporarily; it upset our markets, influenced the price of metals, and affected the labour market and cost of stores. Labour troubles made their appearance before the wave of unrest swept over the world. The cause of labour discontent must be investigated, and if possible removed. As each industry has .its&#183;own problems, miners must inquire into their special problems, as there is no sovereign remedy that will suit all cases.It is obvious that we cannot mine ore if we do not know where it is; therefore, the first thing is to discover workable deposits.

Jan 1, 1919

By R. F. Pilgrim

"This first chapter of the SPOC Manual 1s intended as a general introduction to all the other chapters in which the mineral process evaluation and optimization methodology is presented. This chapter also provides a brief description of available software for mainframe and m1crocomputers and provides information on its distribution by the Technology Information Division. CANMETRESUMECe premier chapitre du manuel SPOC est un guide général qui présente les autres chapitres ou l'on traite de la méthodologie d'évaluation et d'optimisation des procédés miméralurgiques. Le lecteur y trouvera aussi une description sommaire des programmes de calcul développés pour ordinateurs centraux et pour micro-ordinateurs ainsi que la façon de les obtenir de la Division de l'information technologique du CANMETComputer simulation of mineral processes has slowly emerged as an established branch of activity in A&D centres and in several teaching institutions after decades of slow progress. Substantial efforts to develop application software based on years of research on process modelling are being pursued in many countries ( 1 .2,3,4.5). The late BO's should see a flurry of success stones about significant leaps of productivity achieved in several plants through systematic process evaluation and computer simulation studies.In Canada. the SPOC project (Simulated Processrng of Ore and Coal) was initiated at CAN MET in 1980 with the obJective of developing and transferrrng to the mineral rndustry a computer-based methodology for process evaluation and optimization. The proiect deliverables include:- an engineering manual covering most aspects of off-line computer simulation:- a bank of FORTRAN software accessible through data communication lines for user familiarization and distributed at a nominal cost in source form by CANMETThe yearly progress reports of the project contain detailed information on the project elements since 1980 16). The context of SPOC can be summed up by quoting Gordon Agar""s 1975 statement during a workshop on research needs in the mineral industry: ""What is needed is a joint effort between the academic community and one or more enliglitened industrial concerns. The effort will have to be an iterative one with data collection followed by testing the model modification of the model (s), more testing prediction, modification. data collection and so on (7). A few parallel in1- t1atives had been reported in papers or research contract reports (8, 9) but there was an obvious need for CANMET to bridge the gap between the R&D and the production sectors by undertaking a project that would document past applications and induce a new generation of initiatives through the consol1dat1on and transfer of suitable manuals and software. The effort took shape as the CANMET SPOC pro1ect in which methodology transfer was to play a key role (10)."

Jan 1, 1986

By C. A. Brown

"Steady-state simulation has been used for over 20 years to optimise the operation of crushing and grinding circuits. Throughout that period continuing comminution research has been the basis for improving the models.Site surveys, ore characterisation, model development and investigation of different operating scenarios by simulation has proved to be a cost-effective method for improving plant performance. In this sense, this paper presents findings from experience with these valuable optimisation techniques with reference to specific case studies."

Sep 12, 2005

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director&apos;s offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting &, Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. W. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K. Thomson, W. G. Derby, and the assistants of the writer, K. W. McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the a. id of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate any one method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916

By Unknown

Blast Site Security Involves: * Clearing the area * Controlling Access * Warning Signals

Jan 1, 2003

By Chu E. Ho

Current methods of determining jet grout column diameters are highly empirical and site specific, and do not take into account the jet hydrodynamics and soil parameters explicitly. A theoretical model which describes the jet excavation mechanism is introduced in this paper, with the aim of providing an improved prediction tool that can be used in jetting design. The model is based on the assumption that the velocity distribution in the cutting jet is equivalent to that of a free jet with boundaries corresponding to the dimensions of the cavity excavated in the ground. The shape of the cavity formed depends on the erosional properties of the soil and jet expansion is limited by the resistance at the jet-soil interface. The model predicts that the limit of jet penetration is reached when the average dynamic pressure at the jet tip becomes equal to the ultimate soil bearing resistance. The reliability of the model, evaluated using results from four case histories of jet grouting field trials, is within ±15%.

Jan 1, 2006

By Aly M. Mohammad

The Delaware River Tramway will link civic and retail developments in Philadelphia, Pennsylvania and Camden, New Jersey. Twin 300-foot towers will anchor the cables at either side of the river. Four high capacity drilled shafts designed by the Geotechnical Department of DMJM+HARRIS support each of the towers. At the Philadelphia tower, each 6-foot diameter shaft extends 130 feet deep and terminates with a 30-foot rock socket. The shafts are situated within the footprint of an existing relieving platform, which complicates the typical construction sequence. Also, the subsurface conditions at the site provide a unique challenge in both the design and construction of the drilled shafts. During the construction of the four-drilled shafts for the Philadelphia tower, a 6000-ton Osterberg load test was performed on the first shaft to verify design assumption and confirm the shaft capacity. The results of the test were utilized to establish load transfer characteristics and develop foundation design parameters suitable for the site conditions. By doing so the Design Engineer was able to reduce the length of the rock sockets on the remaining production shafts by approximately 5 feet per shaft. As a result, the test provided a significant cost saving to the Owner by eliminating 15 feet of rock drilling from the construction costs. This paper presents a description of the unique design and construction methods adopted for the foundations, also on the Osterberg load test including equipment used, number and locations of strain gages, and interpretation of results. The results and findings presented in this paper could benefit both the design and construction industries because it provides a comparison between geotechnical design assumption and actual field measurements; which has always been a challenge particularly for rock formation.

Jan 1, 2002

By Mehrotra G. M, Frohberg M. G

Based on the concepts of statistical thermodynamics of athermal mixtures, an approach is developed which is capable of quantitatively explaining the thermodynamic properties of binary silicate systems. Expressions for the ionic fractions of various anionic linear and nonlinear chain polymers are derived. The developed expressions for free energy of mixing are tested by applying these to the system PbO-SiO2. The ionic fractions of various chain polymers in this system are calculated. The two cases, namely, of linear and nonlinear chain polymers are compared with each other.Limitations of earlier models are pointed out.

Jan 1, 1975

By J. P. McCullough

In 1943, the Federal Bureau of Mines began a program of thermodynamic investigations of petroleum constituents and related compounds. These systematic, long-range studies, which were conducted in the thermodynamics laboratory of the Bartlesville Petroleum Research Center and are still continuing, have resulted in a substantial quantity of data valuable to the petroleum industry and science in general. As separate phases of these studies were completed, the findings were promptly reported in the scientific press. During the past 16 years, 89 journal articles, giving the results obtained for individual compounds and small groups of related compounds, were published, mainly in the Journal of the American Chemical Society and the Journal of Physical Chemistry. In addition, members of the Bureau staff have contributed six chapters to specialized reference books. This circular, prepared in response to many requests, lists these 95 published papers, giving an abstract of the contents of each, as well as titles, authors, and literature citations. The journal articles are listed in the order of their preparation, which closely approximates the chronological order of their publication; hence, the item number to the left of each citation corresponds to the assigned contribution number. For the convenience of the reader, the abstract section is followed by a condensed bibliography, arranged alphabetically by senior author and keyed to the abstracts by appropriate contribution numbers in parentheses after the entry.

Jan 1, 1961

"It is projected that the reactivity of acid generating tailings and waste rock can be minimized by reducing the access of oxygen by placing these materials under water in natural or manmade lakes. A project under the MEND and B.C. AMO Task Forces has been in progress for four years to evaluate active and historic tailing sites in B.C. and Manitoba. The sophisticated geochemistry studies conducted on the interstitial pore water has illustrated encouraging results which are discussed. The additional studies which are needed to complete the scientific database for the study sites, for achieving regulatory and public approval and for the engineering of application of this method of control are outlined.IntroductionWorld wide research effort is in progress to find the solution to the acid mine drainage problem. A great deal is known about acid mine drainage but much work is required to find economic and effective approaches to the problem. Two coordinated programs have been initiated recently in Canada: the National Mine Environment Neutral Drainage (MEND) program and the British Columbia Acid Drainage Task Force.Disposal of tailings materials under a water barrier such as a natural lake, is thought to be one solution to prevent acid generation by preventing oxygen and bacterial action on the sulphide surfaces. The deposition of reactive tailings materials under water in natural lakes has been used historically at various mines in Canada. However, there has never been a thorough review of the long and short term impacts of historic sites which may provide crucial information to understand the physical, chemical and biological processes which are taking place.This paper provides a general overview of a series of studies which examine the general biophysical characteristics and the sediment geochemistry of four lakes where subaqueous disposal has been or is currently being used for acid generating tailings. The subaqueous disposal studies have been conducted from 1989 through 1991 and were initiated and supported by both research task forces. The objectives of this paper are to summarize the history and the background information of the studies conducted, the general results obtained from each lake, an overview of the major collective results and the additional work which is required to achieve the final objective of developing criteria for applying this technology in the industry."

Jan 1, 1992

By D. Turk, P. Lefebvre, J. Sargent, K. Major

"Stillwater Mining Company recovers platinum and palladium from their Nye Montana operations. Mining first commenced at Nye in 1987 at a milling rate of 455 t/d (500 stpd). The plant was expanded in 1995 with the replacement of the ball mill and the addition of flotation capacity to increase mill throughput to 1820 t/d (2000 stpd). The applications for platinum and palladium have increased in recent years particularly in the automotive industry and the supply of the metals has remained fairly constant with prices for both platinum and palladium increasing and remaining very stable. In 1997 Stillwater initiated the expansion of their operations to increase production of platinum and palladium. Projects were initiated to expand production at the Nye operations, increase smelter and refining capacities at the Columbus facilities and to develop the extension of the orebody at the East Boulder site. This paper will discuss the changes at the Nye concentrator which were completed to increase production from 1820 t/d (2000 stpd) to 2730 t/d (3000 stpd) and eliminate some of the process bottlenecks.IntroductionStillwater Mining Company is mining the only significant primary source of PGMs outside of South Africa. The J-M Reef is an extensive mineralized zone containing PGMs that has been traced over a strike length of about 43 km (27 miles) in the southwest region of Montana. Stillwater controls the entire PGM mineralized zone.Johns-Manville geologists discovered palladium and platinum in the early 1970’s. In 1979, a Manville subsidiary entered into a partnership with Chevron, USA to develop the project. In 1 987, operations at the Stillwater property near Nye, Montana commenced."

Jan 1, 2000

By S. F. Diehl

Weathered mine waste consists of oxidized primary minerals and chemically unstable secondary phases that can be sources of readily soluble metals and acid rock drainage. Elevated concentrations of metals such as Cd, Cu, Fe, Mn, Ni, Pb, and Zn are observed in deionized water-based leachate solutions derived from complex sedex and Cu-Pb-Zn mine wastes. Leachate (USGS FLT) from the Elizabeth mine, a massive sulfide deposit, has a pH of 3.4 and high concentrations of Al (16700 ug/L), Cu (440 ug/L), and Zn (8620 ug/L). Leachate from the sedex Faro mine has a pH of 3.5 and high concentrations of Al (2040 ug/L), Cu (1930 ug/L), Pb (2080 ug/L), and Zn (52900 ug/L). In contrast, higher-pH leachates produced from tailings of polymetallic vein deposits have order of magnitude lower metal concentrations. These data indicate that highly soluble secondary mineral phases exist at the surface of waste material where the samples were collected. Sulfide minerals from all sites exhibit differential degrees of weathering, from dissolution etched grain rims, to rinds of secondary minerals, to skeletal remnants. These microscale mineral-dissolution textures enhance weathering and metal leachability of waste material. Besides the formation of secondary minerals, sulfide grains from dried tailings samples may be coated by amorphous Fe-Al-Si minerals that also adsorb metals such as Cu, Ni, and Zn.

Jan 1, 2011

By Michael H. Wysockey

The load test program for the pile foundation at Soldier Field included static and dynamic load tests at four locations around the site. The dynamic tests were run with no knowledge of the static results, and comparison between the two is very good. It was necessary to use a special testing hammer (not the production hammer) to demonstrate capacity with dynamic testing. Over 90% of the piles were HP14x89 with a design load of 230 tons (18 ksi). The load tests showed a capacity in excess of 590 tons for all tests where sufficient set up time was allowed. The remainder of the piles were mostly HP 12x53 with a design load of 100 tons (13 ksi). The measured capacity of these piles was typically about 250 tons. One experimental HP12×74 pile with a nominal yield of 65 ksi held 730 tons (67 ksi) before failing.

Jan 1, 2002

By Howard A. Perko, M. Mae Benvenga, Heather H. Trantham

Displacement of soil and groundwater during helical pile installation can produce excess pore water pressures (PWP) in fine-grained soils. Pore water pressure reduces effective stress in the soil immediately adjacent to the helical pile shaft and near the helical piles. Previous studies have shown generation of PWP may affect the capacity to torque ratios of the helical bearing elements. Large diameter helical piles that generate much of their torque and capacity from shaft adhesion are affected by PWP and therefore exhibit significant pile "freeze" after installation. Computer modeling is used herein to evaluate PWP immediately adjacent to helical pile shafts during installation in various soil types. The models show the degree and distance from the shaft that is influenced by PWP during installation and the amount of time required for the PWP to dissipate. Pile freeze has been measured on several project sites by re‐torque measurements. These re-torque data are compared with computer modeling and correlations between saturated hydraulic conductivity and dissipation time are presented and discussed. INTRODUCTION Helical piles are full-displacement piles, meaning installation does not produce drill spoil. Soil is displaced laterally as the pile progresses into the ground. This displacement of soil causes an increase in PWP, which reduces adhesion between the pile and the soil. For helical piles with small-diameter shafts, adhesion contributes little to the overall capacity and torque of the pile, so PWP changes are not typically considered in determining pile capacity. In modern construction, the use of larger diameter helical piles has become very common. For large-diameter helical piles, changes in PWP immediately adjacent the shaft can be quite large during installation. Increased pore water pressure and reduced adhesion can have a temporary effect on pile capacity and installation torque.

Jan 1, 2018

By W. S. Steinberg

In 1963, the full-scale engineering study for the development of an iron, steel, and vanadium plant was initiated. This was the birth of Evraz Highveld and its process flow as it is known today. Highveld started out as a steelworks that produced steel and vanadium-bearing slag from a titaniferous magnetite iron ore mined from its own mine site near Steelpoort. The process utilized co-current rotary kilns for prereduction, and submerged-arc furnaces for the production of pig iron with approximately 1.15% vanadium. Because of various technical challenges that the submerged-arc furnaces experienced over the years, a decision was taken in 2004 to convert the furnaces to open slag bath (OSB) operation, in order to enable the maximum production of iron and vanadium while improving the control over operational parameters. The conversion proved to be highly successful and, since 2005, three furnaces have been converted to OSB operation. The fourth furnace will be converted in the first half of 2011. The conversion to OSB furnaces not only yields higher vanadium recovery to the metal at the iron plant, but also improves the overall throughput of the steel plant. This is the result of the higher carbon content of the liquid iron from the OSB furnaces, eliminating the need for anthracite addition to the shaking ladle process. This reduces the blowing time by approximately 60%. The conversion of the furnaces to OSB configuration is seen as an enabling technology change and a prerequisite to the implementation of other plant improvements that are envisaged. The long-term vision of EHSV is to convert five furnaces to OSB mode, and permanently decommission the two remaining submerged-arc furnaces. This will allow EHSV to maintain current steel and vanadium production but at a significantly improved overall efficiency.

Jan 1, 2011

By James V. Errico

On October 1, 1993 the regulations for assessing and cleaning up contaminated soil and groundwater in the Commonwealth of Massachusetts were revised. These new regulations, known as the Massachusetts Contingency Plan (MCP) 310 CMR 40.0000, were developed to keep routine releases out of the regulatory system and rely on private parties to handle most releases without Department of Environmental Protection (DEP) oversight. An integral part of the new MCP is the Licensed Site Professional (LSP). An LSP is required to handle activities and render opinions once a site enters the MCP. These regulations must be adhered to where ever a release has occurred, including construction sites. A brief overview of the new MCP is given below; see attached MCP Flowchart for graphical summary. Entering the MCP Process A release of oil or hazardous material (OHM) to the soil or groundwater above applicable reportable quantities (RQ&apos;s) or reportable concentrations (RC&apos;s) will require notification to the DEP and compliance with applicable provisions of the MCP. RQ&apos;s and RC&apos;s are listed in the MCP (310 CMR 40.1600) for most compounds that are typically encountered. For each compound there are two RC&apos;s for soil (S-1 and S-2) and two for groundwater (GW-1 and GW-2). The S-1 and GW-1 RC&apos;s apply to sites that are environmentally more sensitive, as a result they are lower than the S-2 and GW-2 RC&apos;s.

Jan 1, 1994

By A. Habibi

The ventilation survey was conducted in an underground longwall trona mine. The mine is relatively shallow and categorized as a gassy mine. The ventilation system consists of nine shafts (three intakes and six exhausts). Three surface based axial fans ventilate the mine configured in a blowing arrangement. Following the ventilation survey airflow quantity, frictional pressure losses and air psychrometric characteristics have been quantified. An accurate resistance survey has been conducted to calculate the pressure drop with regard to moving cages and skips in the shafts. This paper discusses the benefits of utilizing high accuracy digital pressure transducers and psychrometers in a ?leapfrogging? survey to gather data needed to build the computer ventilation model. Two underground booster fans with VFD are currently idle but available at the mine. The ventilation model has been used to determine the optimal booster fan locations to decrease the overall operating cost by reducing the load carried by the main fans. A leakage study has been conducted to evaluate the effects on the system of additional pressure from a booster fan. The study finally prepares a future ventilation model for the next fifteen years of mine operation and investigates the effect of proposed scenarios.

Feb 27, 2013