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Mount Isa Mines Ltd. annually extracts 5.6 million tonnes of copper ore from the 1100 Orebody. All production is by longhole open stoping, with an increasing emphasis on pillar recovery. Drilling and blasting prac- tices have been modified to allow more efficient pillar extraction, with the evolution of a "core and shell" approach. Blast design occurs at the stope design stage, while individual blast preparation is based on detailed ring plans. A programme of blasting research involving surface and under- ground vibration monitoring and fragmentation assessment has been car- ried out in conjunction with production personnel. Drilling and blasting practice in the orebody must continue to evolve with continued research, to suit changing conditions and take advantage of new technology.

Jan 1, 1988

By A L. Stewart, M Baatar

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.The Middle Palaeozoic Gurvansaikhan Belt (Southern Mongolia) of the Central Asian Orogenic Belt is one of Central Asia’s most significant emerging porphyry copper provinces. The belt has become the focus of extensive exploration for porphyry copper-gold deposits over the last decade following the discovery of the giant Oyu Tolgoi porphyry copper-gold deposit. The Gurvansaikhan Belt is known to host porphyry deposits of Late Devonian (~370 Ma) and Early Carboniferous (~320 Ma) age. The characteristics of Early Carboniferous porphyry systems are poorly known compared to their older counterparts, despite their probable abundance and potential economic significance. Exploration within the Kharmagtai porphyry breccia complex has identified multiple cogenetic gold-copper-porphyry centres and late-stage mineralised magmatic-hydrothermal tourmaline breccias emplacement within a composite high-K calc-alkaline quartz monzodiorite intrusive complex. Early porphyry alteration and mineralisation at Kharmagtai are zoned around vertically attenuated early- and inter-mineral quartz monzodiorite dykes and stocks and comprises a complex sequence of calc-potassic, potassic and propylitic assemblages. Hematite dusting is a common alteration product that gives intrusions and the host rocks a distinctive pink-orange colour. Several of the systems have bornite-rich cores, where mineralisation is characterised by high gold grades (0.7 to >5 g/t Au) that zone outward to chalcopyrite-rich and then outer pyritic halos. Early stockwork mineralisation is overprinted by magmatic-hydrothermal tourmaline breccias. High-grade magmatic-hydrothermal tourmaline breccias form part of a major copper-gold mineralised breccia system with significant exploration potential. The Early Carboniferous porphyry copper-gold systems of the Gurvansaikhan Belt represent a substantial exploration challenge in an area of increasing exploration maturity. This paper summarises the characteristics of the Kharmagtai porphyry system that have helped to define the Early Carboniferous porphyry province of the Gurvansaikhan Belt and discusses implications for future exploration.CITATION:Stewart, A L and Baatar, M, 2015. The Kharmagtai porphyry breccia complex – characteristics of early Carboniferous porphyry mineralisation in the Gurvansaikhan Belt, Southern Mongolia, in Proceedings PACRIM 2015 Congress, pp 383–388 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Robert D. Brown

"On April 22, 1980, the Ontario government introduced a totally new incentive program for mineral exploration in the province to be effective September I, 1980. Replacing the former Mineral Exploration Assistance Program (MEAP) and also the assistance formerly provided to the mining sector under the Small Business Development Corporations Act, the new Ontario Mineral Exploration Program (OMEP) promises to offer a valuable benefit to certain eligible applicants.Unfortunately, the program is not without its shortcomings: the eligibility for grants or tax credits under the program is comparatively restrictive, and an October 1980 federal budget provision to amend income tax legislation would blunt some of the originally intended attractiveness of the grants and credits.IntroductionIn his budget of April 22, 1980, Ontario Treasurer Frank Miller introduced a new incentive program to encourage mineral exploration in the province.The Ontario Mineral Exploration Program (OMEP) replaces the Mineral Exploration Assistance Program (MEAP), which will be phased out by March 31, 1981. Exploration programs approved under MEAP will continue to qualify for incentives under that program, but will not qualify for OMEP."

Jan 1, 1981

By K. N. Karparov

The classical limit equilibrium methods are suspected to be ineffective in predicting the potential for highwall failure in many instances in coal mines around the world. Slope engineers have for many years recognized a block thrust failure mechanism for slope failures, but little work had been done before 2000 to explain the actual mechanisms which must be responsible for the failure. The main reason for this is that limit equilibrium methods implicitly assume rigid blocks, and the resulting force equations must be satisfied everywhere simultaneously for them to have any meaning. This paper will show that the material involved in the slope failure is not rigid; indeed it undergoes considerable permanent deformation during failure. This observation allows the authors to treat the block boundaries independently, because they need not maintain a constant spatial relationship with one another, as is assumed in other methods. To enable analysis of this type the authors assume that the weight of the blocks is evenly distributed. This is reasonable, because the slope material is not strong enough to be self-supporting without some sort of constraint, or strong enough to be able to apply point loads to the surrounding material. The purpose of this paper is to extend the practical application of the analytical method developed from mechanism studies to provide an objective assessment of the risk of slope failure, and therefore guidelines for more stable slope designs. This work is based on studies carried out on two failures in an open pit coal mine in South Africa, and provides a methodology to assess the potential for failure more objectively than is possible with currently accepted methods, while at the same time remaining sufficiently simple to allow a ?back of the cigarette box? assessment by geotechnical engineers on site.

Jan 1, 2009

By P. M. Wiltcher

The construction of a deep structural slurry wall in a restricted city centre location is always a challenging prospect. However, when the city is London and the site is bounded on two sides by high level canals and a main traffic highway on the third, the challenges are greater than usual. The paper discusses the design considerations required by the principal contractor to accommodate a single high level lateral support, value-engineered, bottom-up construction technique and the impact this had on the design detailing and construction of the slurry wall panels. This paper discusses the logistical challenges successfully overcome during the construction of 65,000sq ft of 40inch thick, 80ft deep structural slurry wall in the City of London. The paper reviews the benefits gained from using the state-of-the-art hydraulic grab and rotator system. Technological advances in computer instrumentation and real time monitoring were utilised to assist the grab operators in consistently delivering deviational control during excavation better than 1:200. With working space always at a premium on construction sites, the need for high quality, pre-fabricated reinforcement cages has never been greater. This paper reviews the argument for off-site fabrication of reinforcement members.

Jan 1, 2006

By R. C. Buehl, J. P. Morris

ACTIVITY values for sulphur dissolved in liquid iron and slags as functions of composition and temperature are needed in applying thermodynamics to sulphur-control problems in iron- and ' steel-making. The purpose of this investigation was to determine the effect of carbon on the activity of sulphur in the metal phase. The method employed was the same as that used in an earlier investigation' concerning the effect of silicon on sulphur activity in liquid iron. A study was made of the conditions of equilibrium in the reaction between hydrogen gas and sulphur dissolved in iron-carbon alloys. The chemical equation for this reaction can be written as follows: S (in liquid Fe-C alloy) + H2 (gas) = H2S (gas). It was found that the activity coefficient of sulphur in liquid iron increases as the carbon content increases. At 2.3 pct carbon and 1600 °C, the activity coefficient of sulphur is twice its value in carbon-free iron, and at carbon saturation it is more than six times as great. The effect of temperature on sulphur activity was found to be small. Previous work on the reaction between hydrogen gas and sulphur dissolved in liquid iron has been reported by several investigators2,³,4 but only recently have studies been made of the effect of alloying elements. Silicon1 is known to have a pronounced influence on the activity of sulphur in iron, its effect being similar to that shown by carbon as described in the present report. Kitchener, Bockris, and Liber-man5 recently have published a preliminary report of their work on the effect of carbon on sulphur activity in iron. Their experiments were made at 1570°C and carbon saturation in the melt. Under these conditions they found that the activity coefficient of sulphur was approximately doubled by the presence of carbon. This is a much smaller effect than that found in the present work. Experimental Method: The apparatus and procedure were essentially the same as those used in the earlier investigation of the effect of silicon on sulphur activity.' Briefly, the method was as follows: A molten iron-carbon alloy was brought to equilibrium at constant temperature with a mixture of H2 and H2S of constant composition by bubbling the gas through the metal. Samples of the melt were

Jan 1, 1951

By R. V. Johnson

The review of mineral activities in Minnesota arrived too late to appear in the May issue. Minnesota continued to lead the nation in iron ore production in 1989 with more than 70% of the market. At no time in the past 50 years has Minnesota's iron ore market share fallen below 50%. 1989 production was provided by six iron ore pellet operations and one high-grade iron ore mine. Most American steel companies are represented in these operations through whole or partial ownerships in Minntac (USS), Minorca (Inland), Eveleth Mines (Armco and Rouge), Hibbing Taconite (Bethlehem), and LTV Steel and National Steel Pellet. A seventh iron ore pellet producer started up in 1989 when Cyprus Minerals acquired the assets of bankrupt Reserve Mining Co. This operation, with first production scheduled for 1990, will be the only non-steel company captive operation in Minnesota. Encouraging minerals development In an attempt to stimulate further and additional mineral development in Minnesota, the state's legislature established a Minerals Coordinating Committee (MCC). This committee is comprised of the Department of Natural Resources-Division of Minerals, the Minnesota Geological Survey, the Natural Resources Research Institute, and the Mineral Resources Research Center. The Committee has sponsored and coordinated various projects. Among these MCC-sponsored projects are glacial drift geochemistry with an emphasis on gold and indicator minerals, accelerated geologic mapping, continued aeromagnetic surveying of Minnesota, greenstone geochemistry, structure and stratigraphy of the Duluth complex, and drill core and exploration data acquisition from past exploration programs. Regarding drill core, the Division of Natural Resources completed construction of its third core library building in Hibbing. These data and core are available for public examination.

Jan 1, 1990

By B. Chalmers, S. Wojciechowski

THE structure of the equiaxed zone of several A1-Cu samples mechanically stirred during unidirectional solidification was examined. The stirring was produced by rotary oscillation of the mold about its vertical axis.' It was found that in Some samples the structure is not of the same type over the whole of the equiaxed zone; it consists of regions with two different etching responses. Fig. 1 shows this structure in a Al-1 wt pct ku sample. The lighter etching regions with a coarse structure form something like a network and the darker etching regions with a finer structure can be observed as the continuation of the coarse structure inside this network. The difference in size and shape of the dendrite branches (they are rounded in the coarser structure) is similar to that found by Williamson and Chalmers in ice crystals solidified in undercooled water: when the amount of undercooling was small, the ice crystals were more rounded and coarser than these solidified with a larger amount of undercooling.' It seems justified to conclude that the observed structure resulted from solidification under different thermal conditions: the coarser structure solidified first out of the "purer" liquid and with a smaller amount of undercooling and the finer was formed later out of solute-enriched liquid under conditions of much more rapid heat extraction. A considerable change in the heat flow conditions at the later stages of solidification can be easily understood by taking into account that the coarser crystals form a continuous network and the amount of trapped liquid is relatively small; hence the contribution of latent heat is much smaller in the later stages of solidification. The difference in structure and etching characteristic reflects a difference in composition between these two regions. It was found that the darker etching re- gions are harder (30.4 to 31.3 HV5) than the lighter etching ones (25 to 26 HV5). A similar type of structure was found in a A1-4 wt pct Cu sample grown by Czochralski method. Fig. 2 shows the structure in the lower part of a sample grown slowly and then decanted by a rapid removing of the sample from the melt. In a few places trapped liquid solidified in the same manner as in the sample shown in Fig. 1.

Jan 1, 1968

By S. D. Maksimovic

The use of vertical surface degasification boreholes with bleeder systems and the use of a timbered bleeder system to degasify gob areas were studied by the Bureau of Mines. This report describes three gob degasification studies conducted in the Pittsburgh coalbed. One study was conducted to determine the number of panels degasified with one large borehole. The study showed that the borehole provided degasification for three panels. Another study was conducted during the retreat of a 35-acre panel with a single-entry and a two-entry bleeder system and a large surface borehole. A major portion of methane emitted from the panel was carried away by the bore-hole, leaving the bleeder entries relatively free of methane. The last study was made to determine the effectiveness of a timbered bleeder system. The bleeder entries successfully degasified the gob area when enough entries were available and adequate pressure was available to force the air through roof falls.

Jan 1, 1980

By Ralph J. Schilthuis, William Hurst

The nature of the forces that are important in producing the oil in the East Texas field and the manner in which these forces are affected by the rate of production have always been problems of outstanding interest. These questions are of great interest to the industry as a whole on account of the economic importance of the East Texas field and to the engineers in particular on account of the unique character and behavior of the field. Subsurface pressure data throughout the field have been collected systematically, so that a quite complete history of the reservoir pressures has been kept as the field has been developed and produced. Subsurface samples of the oil and gas have been taken and these have been examined to obtain data on the physical properties of the reservoir fluids under the actual conditions of temperature and pressure. All of these data have been valuable because they have afforded the basis for a careful study of the means by which the oil is produced. It is the purpose of this discussion first to point out several of the important facts revealed by the data mentioned and then to describe studies that have been made concerning the interpretation of these facts. Reservoir Pressure Data and Properties of Oil The reservoir pressure data on the East Texas field have shown conclusively that the pressures are readily affected by changes in the rate at which the field is produced. This can well be seen in Fig. 1, where the average reservoir pressures obtained from time to time are plotted with the daily production rates and the cumulative production of the field. It is noted that the average reservoir pressure has declined irregularly, depending upon the rate of production, from the estimated original value of 1625 Ib. per sq. in. to the value of 1228 lb. per sq. in. observed for Aug. 11,1934. The decline in pressure has been more rapid at the higher rates of production than at the lower rates. In contrast, the average reservoir pressure has increased, on several occasions, upon reduction of the withdrawal rate from a high value to a lower value. The reservoir pressure data have also shown that a definite gradient in pressure has existed across the field from west to east since the begin-

Jan 1, 1935

By Santosh Kumar Ray, DEBASHISH MISHRA, Niroj Kumar Mohalik, SOMU MANDAL, Jai Krishna Pandey, Asfar Mobin Khan

Coal is a low-cost and high-calorific-value fuel. The coal mining industry worldwide has been suffering from severe accidents due to coal dust explosion hazards since its inception. Statistically, it was observed that 12,489 fatalities had occurred in 104 reported mining accidents from coal dust explosions during 1900–2020. There are numerous methods for detection, prevention, and control of coal dust explosions in mines. The underground mining environment is unpredictable and has an array of variables. These undulating factors make it difficult to prevent or control the coal dust explosion hazard. However, coal mining is done aggressively throughout the world, especially in developing countries as coal is a major source of thermal energy used in power plants contributing to about 38% (IEA, (2019), World Energy Outlook, IEA, Paris https:// www. iea. org/ repor ts/ world- energy- outlo ok- 2019.) of world electricity. Worldwide, coal dust explosibility studies are carried out in experimental mines, laboratories, and simulations. The complexity, lack of proper infrastructure, and unavailability of laboratory equipment sometimes make it difficult to study coal dust explosibility. The authors have discussed in detail and proposed that the CFD modelling can be a viable option for studying and evaluating coal dust explosibility.

Jun 29, 2022

By H. E. Powell

The magnetic susceptibility, the geographical source, and associated minerals are given for 44 copper-, 26 lead-, and 19 zinc-bearing minerals. Of the 44 copper minerals/ all had a susceptibility of less than 15 X 10-6 cgs, and about 20 percent of them were diamagnetic. Of the 26 lead minerals, all had a susceptibility of less than 11 X 10-5 cgs, and almost half of them were diamagnetic. And, of the 19 zinc minerals, all except four had a susceptibility of less than 9 X 10-6 cgs, and about one-fourth of them were diamagnetic.

Jan 1, 1968

By Matti J. Saarivirta

Two new precipitation hardening copper-base alloys, Cu-1.5pct Ti-2.5 pct Sn and Cu-1.5 pct Ti-2.5 pct Sn-0.4 pct Cr were developed. High strength and medium conductivity are obtained by solution annealing and subsequent heat treatment. Combination of solution annealing, cold working, and heat treatment increases the strength further. Good elevated temperature strength and ductility makes these alloys superior to copper-beryllium-cobalt alloys. A considerable amount of research work is being done throughout the world to develop new and improved copper-base alloys. In many cases, the object is to develop alloys having a combination of high electrical and thermal conductivities, and high strength. The problem is complicated by the fact that any alloying element added to increase strength, invariably decreases conductivity. Among the few commercial precipitation hardening type copper-base alloys, the Cu-Be-Co alloys are best known. These alloys are used in many applications that require good spring characteristics cornbined with high strength and moderately high electrical conductivity. They can be formed readily after solution annealing, then heat treated to obtain high strength and conductivity. Because of the relatively high cost of the Cu-Be-Co alloys, considerable research has been aimed at developing new lower cost alloys having similar properties. As far as is known today, the binary Cu-Ti alloy is the only one whose properties are

Jan 1, 1962

By W. J. Uren, Charles R. Kuzell

The industries engaged in winning minerals from the earth, because of their widespread dissemination, are faced with perhaps as wide a variety of labor-management problems as may be found in any other broad sphere of productive activity. Those problems are continually increasing in volume and complexity, and management has become aware of their growing importance. For the past quarter century at least, labor-management problems have largely been union-management problems. During this period tremendous assistance has been given labor unions through legislation and administrative and political action. In the United States, legislation favorable to unions has come about in the form of the now defunct National Industrial Recovery Act; the Wagner Act, most of which has been carried forward in the Taft-Hartley Act; the Norris-La Guardia Act; the Wage and Hour Law; the Walsh-Healey Act; and others. The result has been to transfer from the hands of management to those who direct the affairs of the unions a large share of control over the industry and to hamper in many ways the remaining control left to management. In the United States there are many examples of the power of unions to injure whole industries seriously with- out regard to the interests of management, the employes, or the public. This chapter deals with the various phases of labor-management relations as they affect the principal segments of the mineral industry in North America. To the greatest extent possible available data is presented pertaining to the unions involved, their relative strengths, labor law, compensation and fringe benefits of employes, working conditions, and related matters. As background, the historical development of union-management relations in the respective segments is included where possible. The section dealing with the United States has been divided into separate

Jan 1, 1959

By N. A. Barcza

An investigation was conducted into the reactions between the slag system MnO-CaO-MgO-SiO2(AI2O3) and the alloy system Mn-Fe-Si-(C). Synthetic slags representative of plant melts and a plant alloy were reacted in alumina crucibles at temperatures of 1400°C, 1450°C, 1550°C, and 1600°C. In similar experiments, slags were used that comprised a South African manganese ore with various amounts of lime and several synthetic alloys with various silicon contents and manganese-to-iron ratios. These experiments were conducted in a vertical molybdenum-wound resistance furnace with full temperature control. Slag-to-alloy ratios were also varied during the tests. The rate of reduction of Mn.O3 and the MnO from the slag by the silicon in the alloy was extremely rapid, most of the reaction being completed within five minutes. The strongly exothermic nature of the reaction resulted in considerable generation of heat at the slag-alloy interface, causing convectional stirring of the contents of the crucible and promoting the rate of reaction. Equilibrium was usually attained after fifteen minutes. The major limitation governing the recovery of manganese is the need for the silicon content of the alloy to meet a maximum specification of 2 per cent. Higher concentrations of silicon in the final alloy of between 8 and 12 per cent favour good recoveries of manganese from the slag, but, since such an alloy is not salable, lower recoveries must apparently be tolerated. In alloys of 2 per cent silicon, low activities of the silicon are responsible for poor recoveries of manganese. The activity of MnO in the slag can be increased by moderate additions of CaO and small amounts of MgO, i.e., by an increase in the basicity of the slag.

Jan 1, 1979

By H. H. Uhlig

SINCE its first mention in the literature in the eighteenth century1,2 the phenomenon of passivity in metals has stimulated much speculation and attendant controversy as to its nature and cause. No one of the numerous theories so far proposed has been generally accepted. ? Faraday,7 in 1836, associated the passivity of iron with a protective film over the surface of the metal, which materially prevents or slows down reaction with corrosive environments. His theory was that oxidizing acids like nitric acid form an unstable oxygen or oxide layer over the iron surface, which protects the underlying metal from further attack. This concept was simple yet plausible, and without alteration has frequently been assigned in present-day discussions as explanation of the passivity of many metals. With the advent in recent times of stainless steels, it is not surprising that this oxide film theory of passivity proposed by Faraday has been used to explain the phenomenal corrosion resistance of stainless steels and other passive alloys. The passive alloys, such as the chrome-iron alloys, are supposedly covered with a protective oxide film, which forms on exposure of the alloy to air, is extremely stable and self-healing, and accounts for the remarkable resistance of these alloys to corrosion. Within the past few years, several investigators, following the theory of film protection, have attempted to gauge the resistance of the supposed film on steels. Brennert8 and Donker and Dengg9 determined the poten-tial at which a negative ion (e.g., Cl-) moving in an electric field reacted with the metal anode, as detected by increased current flow or change in potential of the steel electrode in an electrolytic cell. The potential corresponding to reaction Brennert called the film break-through potential.

Jan 1, 1939

By D. H. Magoon

The zinc smelter of Cominco Ltd. at Trail, B.C. Is the largest In the western world. A total of 550.000 tonnes of concentrate are proceed at the smelter annually. Approximately 80% of the zinc concentrate is roasted and the remainder Is treated by aqueous oxidation preaaure leaching. The zinc concentrate roasting and sulphur dioxide gas processing plants have undergone many changes over the years. This paper describes the processes and equipment currently used for concentrate roasting, S02 gas cooling and cleaning, mercury removal, sulphuric acid production liquid S02 production, and tall gas S02 scrubbing. The recent Installation of an advanced process control system for the operation of these Integrated processes Is also described.

Jan 1, 1990

By G. H. Lovell, W. J. Parton, J. J. Crane

IN 1949 Lehigh Navigation Coal began a study to improve its mining methods. At this time the company mines were using conventional breast and pillar and slant chute methods to mine the. steeply pitching coal (40º to 90º). Mining costs were high, the miners' productivity low. There were many hazards typical of the methods employed. Coal seams in the Panther Creek Valley area of the southern anthracite field form a syncline dipping 40" to the south and 75º to 80º to the north, the lowest point 1500 ft from surface. Several contiguous veins 7 to 50 ft thick are mined. Characteristic folding is shown in Fig. 1.

Jan 3, 1957

By I. I. Inculet, M. A. Bergougnou, J. D. Brown, R. M. Quigley, D. K. Faurschou

"Coal from Hat Creek, B. C., has been successfully beneficiated to remove ash while retaining calorific value by a dry electrostatic separation process using a fluidized bed for triboelectrification. Two samples of Hat Creek coal used in the beneficiation experiments have been characterized particularly with respect to their mineral and clay content. The calorific value recovery exceeds the simple dry coal recovery because of the heat lost in altering the clay minerals of the ash fraction during burning. Recoveries and ash contents of the beneficiated coal are comparable to recoveries by water washing, but the dry process avoids the potential water pollution problems.IntroductionProposals have been made which suggest an interim Canadian coal production target for the end of the century which will require a four- to fivefold increase over the 1977 production. This implies a nominal annual growth rate of about 6070 to achieve a production rate of 115 to 140 million tonnes/year. Whether or not this target is realistic, it is becoming increasingly evident that coal must be utilized more fully on a world-wide basis. The crisis in Iran has provided the latest stimulus to renewed interest in Canadian coals for domestic use and export.The emerging new era of coal utilization for fuel and chemical feedstock will not, however, generally tolerate the level of coal technology which prevailed prior to the availability of abundant cheap oil and natural gas. Economic, environmental and resource management considerations will necessitate, for example, the use of improved methods of beneficiating coal. Continued development and application of conventional processes, principally aqueous, involving heavy media and cyclones will solve many of the problems. However, less conventional processes may be preferable or necessary in certain applications."

Jan 1, 1980

By François G. Bernardeau

Cement-bentonite (C-B) slurry walls have been used for ground water cutoff in deep excavations, contamination containment, and other applications. Hydraulic conductivity is of great concern for cement-bentonite slurry walls. The quality control program usually specifies permeability and strength tests to be performed in a laboratory on samples cast in the field and cured for a certain time. Currently there is no widely accepted in-situ test method for the performance of the constructed slurry wall. A recently constructed cement-bentonite slurry wall in South Carolina included a 200-foot-long test section done in advance of the production of an 8,300 foot-long wall. Intensive tests and investigation were conducted during and after the test section construction: Monitoring piezometers were installed using wet insertion method and packer tests were conducted in boreholes drilled in the post-28-day-cure slurry wall. The permeability measured from the packer tests was about two orders of magnitude higher than the design and the laboratory test values. Additional investigation was performed using a video camera to inspect the borehole walls especially the packer test sections. Test pits were excavated to observe both sides of the cement-bentonite slurry wall. A thorough inspection was conducted to evaluate the integrity of the wall. The lessons learned and issues regarding the disturbance effects of in-situ testing of cement bentonite slurry walls is presented and discussed.

Jan 1, 2008