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By J. C. Stankus, K. J. Ma, D. Faulkner

To protect mine personnel and moving equipment at underground roof fall areas, mine operators typically install steel sets, which are covered with wooden blocks and backfilled with an expanding-type cement material. In large roof falls, the cost of void backfilling becomes prohibitively high, causing some mines to leave the voids open. However, the durability of wood over time and the capability of the steel set and wood lagging to resist falling rock are unknown. This has caused concern for the U.S. Mine Safety and Health Administration (MSHA) and ground control engineers. During the last few years, Keystone Mining Services, LLC developed various impact-resistant steel set designs that were approved by MSHA and installed in various underground fall rehabilitations. This paper presents an impact-resistant steel set design methodology, including (1) steel set design per AISC national standard, (2) design, development and laboratory testing of a waterproof coated impact-resistant lagging panel and (3) impactresistant steel set design based on the law of conservation of energy. Two underground cases will be included detailing the application of the system.

Jan 1, 2011

By V. Svalbonas

When the Trelleborg Divisions of Boliden Allis and MPSI merged, a unique opportunity occurred for two independent mill fabricators to compare various design procedures and the research upon which they were based. This paper documents such a comparison in the structural design area. Several SAG mill analyses are compared using both Boliden Allis and MPSI methods. The differences and similarities are then utilized in a correlation of critical stress definitions and the acceptable design and inspection criteria.

Jan 1, 1992

By J. Brent Hiskey

INTRODUCTION Metal electrodeposition processes are of fundamental technological importance to a number of fields. Electrorefining, electrowinning, electroplating, and electrogalvanizing have all been the subject of intense study for over a century. More recently, electrochem- ical deposition has played a critical role in advances in microelectronics and lately has been an enabling technology for the production of certain nanostructured materials. Electrometallurgists have most frequently been concerned with the structure and morphology of massive deposits. For example, in metal recovery steps such as electrorefining and electrowinning, deposits demonstrating adherent coarse-grained characteristics are most desirable. In the case of electroplating, a bright fine-grained, tenacious and strongly adherent deposit is required. The fabrication of microelectronic devices and the production of nanoscale structures such as nanoparticles, nanowires, and nanorods requires a keen understanding of early stage deposition effects. The initial stages of metal deposition, usually referred to as electroclystallization, are fundamentally linked to nucleation and growth phenomena. Early stage deposits are typically very ordered. Whereas, bulk metal deposition structures are much more ran- dom. In both cases, the discharge of a metal ion at an electrified interface is represented by simple cathodic reduction as follows: [ ] Me(H2O)xn[ ] is a hydrated metal ion residing in the bulk solution and Me is the metal atom occupying a crystallographic lattice position. A similar reduction reaction can be

Jan 1, 2005

By N. I. Fedunets

The development of variousworks on automatising of operational processes at coal¬extractive and coal-mining enterprises introduces an ever growing necessity to carry out investigations in the wide range of problems concerning the possibitity of joint functioning of different levels, which seems impossible without the use of integrated systems of passing on and prossessing the information on the basis of modern calculating machines and other means of automation. This view on the problem of automation of the enterprise operation presupposes that the structure of automated operational dispatcher control (AODC) should be very closely connected with that of integrated data processing system! In this case the AODC structure from the point of view of automation of its functions (or operations), i.e. from the point of view of informational techniques coinsides in general with the structure of dispersed information and calculating network (ICN), realizing the passing on and processing of the information as well as solving the functional tasks on the basis of local calculating networks of electrical calculating machines with correspond to different levels of AODC and located with regard to productional hierarchy of operational dispatcher control (ODC). In this approach however the use of dispersed, ICN gives opportunity to. realize the possibility of action only with realisation on the CM of algorithmic' task of ODC, when a dispatcher 'is the lastto make a final decision.. At the mining enterprises it's rather difficult for a dispatcher to make a final decision because of the great variaty of productional situations, the presence of contradictions and a number of other subjective factors which often lead to the dispatcher's mistaks causing great material losses of the enterprise. Hence the necessity arises to automize and formalize making a decision and including the expert systems (ES) into the ontour of AODC, which enables the dispatcher 2to get a neeessary advice in different situations, especially in case ofemergency on the basis of establishing the mechanism of logical layout of non-formalized data base (DB) procedures relying upon the background knowledge and experience of experts. The presently presented in this paper theory of establishing the. ISAODC on the basis of dispersed ICN and expert systems is aimed at trasformation ofoperational' tasks of the higher level into the technological ones, at solving the tasks of diagnostics and forseeing of the process of production, with a dispatcher getting an opportunity of making qualitative and effective decision concerrning the choice of operational impacts in actual time on the basis of generalization the realisation of presented conception must, as has been already mentioned, be accomplished only on the basis of the foundatoin of the united dispersed informational - calculating network of electrical calculating machines.. This includes ICN which would be operating in . different operational contours. . From what has just been said it followsthat the ISAODC Structure will conside with that of DICN (in our case) and hence all the problems of ISAODC structure would be regarded as the questions of DICN.

Jan 1, 1992

By Matthew Grzelak, Gulsah Erinc, David R. Chapman

"The third phase of the Bagram Drainage System project at Bagram Air Force Base in Afghanistan included construction of a shallow, 540-m long, 1.8-m inside diameter drainage tunnel. The tunnel penetrated mostly stiff to hard clayey and silty soils. The contractor’s Value Engineering Change Proposal (VECP) to use pipe-jacking with a microtunnel boring machine (MTBM) instead of the specified two-pass Earth Pressure Balance method was evaluated and supported using hand calculations. Contractor support was provided throughout the project by providing design reviews and instrumentation monitoring during construction. This paper compares the value-engineering proposal to the specified method and describes the construction conditions encountered. INTRODUCTION As part of a larger improvement project at the Bagram Air Force Base in Afghanistan, a shallow, 540-m long, 1.8-m inside diameter drainage tunnel was constructed to provide additional capacity for Coyote Creek to pass below several critical structures, including taxiways and the main runway, for mitigation of recurring flooding (see Figures 1 and 2). Overburden over the tunnel crown ranged from about 3 m to 5.5 m. An existing cast-in-place twin barrel concrete culvert runs approximately parallel to the new tunnel and is within about 8 m at its closest point. The contractor’s Value Engineering Change Proposal (VECP) to the specified two-pass Earth Pressure Balance (EPB) method (steel ribs and lagging or steel liner plate with a carrier pipe later grouted in-place) called for installation of the required drainage pipe by pipe-jacking (one-pass installation) using a slurry microtunnel boring machine (MTBM). The critical nature of the operations at the air base resulted in significant construction coordination challenges and a greater than usual need to avoid excessive settlements. Substantial restrictions were placed on drilling of investigative borings and installing instrumentation near runways and taxiways due to drill mast height. The prime contractor was SERKA TAAHHUT INSAAT A. S. (SERKA), the microtunneling subcontractor was Ludwig Pfeiffer Microtunnel GmbH & Co.KG (Pfeiffer), the jacking pipe designer was Gollwitzer Pipe and Shaft Technology GmbH (Gollwitzer), and the contractor’s tunnel engineer was Lachel & Associates, Inc. (Lachel). Lachel provided contractor support throughout the project including preparation of a VECP/Design Summary (including interpretation of existing and new geotechnical information), design reviews for jacking pipe, estimating settlement of an existing drainage structure above the new tunnel, and instrumentation planning, monitoring, and analysis during construction."

Jan 1, 2016

By Matthew Price, Laura Brown, Atulya Verma, Samantha Espley

Burst-prone conditions are a significant hazard in deep hardrock mines, elevating the risk to excavation stability and, more importantly, to worker safety. As mining progresses deeper, induced stress changes may trigger the initiation of rock failure processes which can be detected and recorded as mine seismicity. The implementation of seismic monitoring and routine seismic data analyses enables mine seismicity to be quantified spatially, temporally and on scale. The ability to quantify and characterize mine seismicity offers the opportunity to gauge seismic hazard, identifying high risk zones for mitigation against burst-prone excavation failure. Over the last decade, the Mines Technical Services (MTS) group at Vale Canada Limited’s Garson Mine assessed seismic hazard with the objective of assigning practical mitigating controls to zones identified as having a high rockburst potential. Initially, seismic hazard was computed using the Seismic Excavation Hazard Mapping (SEHM) software developed by the Mining Innovation Rehabilitation and Applied Research Corporation (MIRARCO) at Laurentian University, Canada. More recently, Vale Sudbury Operations partnered with the Australian Centre for Geomechanics and the University of Western Australia’s mXrap consortium. Through the consortium partnership, MTS at Garson Mine implemented the mXrap seismic data analyses platform, including the grid-based seismic hazard assessment tool. Building on 10 years of seismic hazard assessment experience at Vale Garson Mine, this paper summarizes a comprehensive case study, comparing the two tools (SHEM and mXrap) used at Garson Mine to assess, quantify, and represent seismic hazard. Subsequently, results of the Garson Mine comparative seismic hazard study will be discussed, emphasizing the need for an all-inclusive hazard assessment tool, focused on delivering practical mitigating controls that further enhance the overall safety of seismically active underground mines.

Apr 26, 2022

By B. W. Cavender

"World-class manufacturing" (WCM) techniques can be applied in milling operations to substantially improve productivity and reduce costs. Through the use of "just-in-time" and "total quality control" practices, WCM methods establish an environment for continual and rapid improvement in all aspects of production operations, with particular gains in product quality, costs, flexibility, employee involvement, and responsiveness to customers. This paper examines WCM techniques that can be utilized specifically in the mill, and their influence on plant configuration, organization, and scheduling practices; equipment selection and maintenance methods; training; the role of supporting staff; and methods of data collection and analysis.

Jan 1, 1993

By Igor Gonzales G.

Southern Peru Copper Corporation (SPCC) has recently completed the construction of copper leaching, solvent extraction, and electrowinning facilities at their Toquepala and Cuajone plants in Southern Peru. Much of the ore for these new operations is the result of the existing mining operations that have been in existence as early as 1959. At Toquepala, pre-conditioning and bacterial dump leaching of the sulfide ore that was too low in copper content to be processed through the copper concentrator began in 1987. The Cuajone heap leach operation is treating copper oxide ore that has been stockpiled since the Cuajone concentrator began operation in 1976. The pregnant leach solutions from the dump leaching at Toquepala and the permanent pad heap at Cuajone are combined into one plant feed solution. Adjacent to the large dumps at Toquepala, a solvent extraction and electrowinning facility has been constructed. The electrowinning facility has a planned annual production rate of35,000 metric tons per year Grade A cathode copper. Initial production of the cathode copper began in November 1995.

Jan 1, 1996

By Sidney A. Suhler

The persistent requirement for methods and equipment capable of detecting hazardous anomalies in advance of underground mining has led to the development by the U.S. Bureau of Mines of a directional radar probe. The probe operates from boreholes drilled from the surface into the underground region to be mined. The engineering model radar was completed in early 1982 and field demonstration tests were performed in May of that year at a selected coal mine. Preliminary in-situ electromagnetic tests were performed at several candidate coal mines to evaluate the radio-frequency characteristics of the coal. A coal mine in New Mexico was selected on the basis of low EM propagation losses in the coal and the presence of an extensive coal seam displacing fault as a radar target. The borehole radar was operated in two vertical boreholes which intersected the coal seam at approximately 25 and 40 feet from the fault interface. Radar reflections from the coal/ rock interface were detected in both tests. Underground tests in a horizontal borehole in the coal were less successful because of interfering reflections. Additional borehole-to-borehole tests were performed with a separate ground penetrating electromagnetic system to obtain radar range calibration data. The coal was found to be bounded by very lossy roof and floor sandstone and shale while propagation through the coal seam was obtained at distances up to 175 feet between test boreholes. Coal seam continuity was indicated by the hole-to-hole experiments through a section of the seam previously thought to be completely cut off by the fault.

Jan 1, 1983

By Richard B. Muter

In determining the layout or combination of unit operations to be utilized in a modem preparation plant, several factors must be taken into account. Among these are the washability data, size consist data, the particular market or markets for the coal, the mining method used, the degree to which the coal must be prepared, expected fluctuations in raw coal and markets, and the overall economics of the process. In addition, there are the health and safety aspects of coal utilization and preparation. Chapter 1 of this book discusses the characteristics of coal and coal markets, while Chapter 2 deals with the design of preparation plants. Once the unit operations for a particular plant have been decided upon, these arrangement may be depicted by using a flowsheet. A coal preparation plant flowsheet is a two-dimensional graphical representation of the sequence of operations, the arrangement of machinery, and the flow of materials for a particular coal cleaning operation. The flowsheet is usually qualitative in nature, becoming more quantitative as material balances, water balances, numbers and sizes of various pieces of equipment, etc. are added. The usual convention in preparing a flowsheet is to show the feed flowing from left to right, starting at the top left and working down as in an all-gravity process. Various symbols are used for each unit operation as depicted on a flowsheet, and Fig. 14-37 is a compilation of the commonly accepted international standard symbols for each unit operation. Fig. 14-38 through Fig. 14-40 are flowsheets of various coal cleaning processes as published in the January 1976 issue of Coal Age. Each process has its own unique features which, among others, depend upon the coal being cleaned, the coal market, and the mining operation. Fig. 14-38, for example, is a flow diagram for a jig plant preparing steam coal from two strip mines located a few miles apart. In addition to the jig washer, cyclones are used to treat the finer size coal. Fig. 14-39 is a flowsheet of a heavy media plant using a heavy media washer for + %-in. (+6.3-mm) coal, froth flotation for -28 Tyler mesh (-0.6 mm) material, and dewatering phase units (dwp) for Y, in. x 28 Tyler mesh (6.3 x 0.6-mm) cleaning of steam coal. In addition, thermal drying, centrifuge drying, and the use of vacuum disk filters and thickeners for dewatering are depicted. Fig. 14-40 is a flowsheet of a plant producing metallurgical coal. In addition to the heavy media and froth flotation circuits, a tabling circuit is also employed. These flowsheets are intended to give the reader an example of how the various unit operations for coal cleaning may be linked together. Figs. 14-41 and 14-42 illustrate the conversion of block diagrams into an IS0 prescribed set of symbols.

Jan 1, 1991

By John W. Lane

Climax Molybdenum Company, a Division of American Metals Climax, Inc., operated a hydrometallurgical plant* at Climax, Colorado from August 1966 through August 1968 to recover molybdenum from a mixed oxide and sulfide ore. The ore treated for this addition to the existing plant contained sufficient Molybdenite values to be mined for Molybdenite recovery alone, so that the oxidized molybdenum recovery could be regarded as a byproduct operation. Climax is located at an elevation of 11,300 feet. All process equipment, except thickeners, was enclosed in buildings. Annual snowfall is approximately 250 inches per year. Paved highways and rail service to the plant are maintained and kept open all year. Most of the employees live in the town of Leadville, which is approximately twelve miles from the plant site. The sulfide flotation plant handles 40,000 to 45,000 tons per day of ore. The mine is one of the world's largest underground mines.

Jan 1, 1971

By Y. C. Kim

Three rock fracture parameters define three points along empirical cumulative size (of rock fragments) distribution curves at Inspiration copper mine. These parameters are: rock quality designation (RQD), longest piece of intact rock and % of +1 inch. The RQD and the longest piece are actually measured on drill hole cores whereas % of +1 inch is visually estimated on the same cores. These size distribution curves are then utilized in a variety of engineering applications such as; slope instability analysis, blast design, copper recovery prediction from heap leaching, etc. The three rock fracture parameters for two dominant rock types (porphyry and schist) in the pit had to be estimated separately due to different rock fracture characteristics.' Both ordinary kriging (OK) with measured hard data only and soft kriging (SFTK) with hard and soft data were used to estimate each parameter. The cross validation of 100 measured sample values served as the-basis for evaluating the potential benefits of SFTK over OK. Use of subjective information during SFTK required obtaining (prior) probability distributions for all three rock fracture parameters. These distributions were obtained from the typical rock fracture parameters observed in drill hole cores falling inside the geologically interpreted structural domains with varying degrees. of fracture intensity and also through direct mapping along the exposed bench faces. Two different types of soft information were developed for this study; namely, Type "A" and Type "K". The former is based on sample distribution of fracture parameters whereas the latter is based on two step estimation designed to narrow the range of variation observed in data Type "A". The results of the cross validation were analyzed using a linear regression of actual values versus estimated values. The results confirm an improvement on the estimates made by SFTK with hard and. both types of soft data over those produced by OK with hard data only.

Jan 1, 1989

By Kenneth S. Graham, S. C. Gambrell

A short term, simple roof bolt load cell which uses a birefringent (photoelastic) coating as its sensing element has been developed. The load cell is installed between the bearing plate and the nut/washer and measures the initial force after installation by the bolting machine. The load cell can be removed from the bolt and used again to measure initial force in another bolt if desired. Because temperature and humidity changes in the mine cause creep/relaxation of the coating and/or adhesive, the load cell is useful for accurately measuring force for a period of only two weeks after installation. Force in the bolt is determined by referring to a calibration curve for the load cell.

Jan 1, 1992

By Manuel Viveros J.

This paper will deal with the type of rocks so called evaporites, which are sedimentary rocks produced by water evaporation from seas, lakes or marginal lagoons, in warm and arid climates. Salts derived from these deposits are precipitated according to their solubility; that is, the more soluble precipitates first, overlain by other sediments like silts, shales, limestones, sands, etc. The most common evaporites, according to their chemical composition, are : Chlorides Sulphates Carbonates Nitrates Borates Common salt, or halite, sulphates like anhydrite and gypsum, are the most important. Potassium chloride (silvite and carnalite) and potassium sulphate are of great commercial value.

Jan 1, 1974

By W. W. Kephart

The glass container industry is the largest producer of glass in the United States. As of this writing, there are approximately 89 active domestic production locations. In 1984, the industry shipped 11.8 million tons of glass containers. Approximately 70% of this production was clear or flint glass, 20% amber, 7% green, and the remainder miscellaneous colors. Although the production of nearly 12 million tons of glass is impressive, anyone following the industry over the last five years is aware that the industry has changed from a pattern of growth in the 1970's to one of maturity in the 1980's. Some observers, less generous, perhaps, have described the 1980's as a period of decline. In 1981, there were 119 production facilities which produced 13.2 million tons of glass the previous year. This equates to a 10% reduction in glass container production from 1980 to 1984, with a corresponding impact on the segment of the industrial minerals producers serving the container glass industry, as shown in Figures 1 and 2.

Jan 1, 1986

By Valerio Violo, Antonio Raschilla, George Kafantaris

"The Cityringen project in Copenhagen, Denmark will form a new circular line in the city center and will consist of 21 new stations (17 + four transfer stations) and approximately 31 km (19 miles) of earth pressure balance (EPB) twin-bored tunnels.The new tunnels passed under the historical building of Magasin du Nord, McDonald’s and two pubs in the heart of the city with a minimum cover of about 4 m (13 ft).To minimize the movements, a complex system of compensation grouting and jet grouting soil treatment was performed. A detailed action plan between the parties involved allowed coping with the critical tunnel boring machine’s (TBM) successful passage.The Cityringen is an extension of the existing metro line underground Copenhagen and will include the City Circle Line, 15 km (9.5 miles) of twin tunnels looping around the city. The City Circle Line will form a new circular track inside the city center and will intersect the existing M1 and M2 lines at Kongens Nytorv and Frederiksberg stations, as well as suburban train services at København H, Østerport and Nørrebro. It will extend the Metro network to the Nørrebro, Østerbro areas and the central station at København H (Fig.1). The two new lines M3 and M4 will run on the same tracks, but the M3 will be a circle route running around the entire line, whereas the M4 will drive from the station to the north side of the city.The €1.5 billion design-build contract was awarded by Metroselskabet in January 2011 to the Copenhagen Metro Team (CMT), a joint venture (JV) between the Italian companies Salini, Tecnimont Civil construction and Seli SpA. Since the bankruptcy of Seli SpA and Tecnimont, Salini Impregilo now owns 100 percent of the JV shares. Seli Tunneling Denmark ApS, a subcontractor to CMT, was initially constituted as a Seli SpA subsidiary and, following the economic difficulties of Seli SpA, was acquired in 2015 by Salini Impregilo. Seli Denmark is in charge of the tunnels excavation and lining and owns the four 5.84-m (19-ft) diameter Seli/Kawasaki earth pressure balance machines."

Jan 5, 2017

By Richard Giffen, Boris CARO VARGAS, Terrence Carroll

"This paper takes an in-depth look at the $72 million design-build Norris Cut project, which includes the replacement of an existing 54-inch waste water sewer main to Fisher Island under the Norris Cut Channel. Tunneling through one of the country’s most unpredictable geologies created unique challenges in both the design and construction phases of the project. The paper presents the geotechnical and structural design considerations for the 100-foot deep secant piled TBM launch shaft in the highly permeable Fort Thompson formation limestone and sands. The structural design effort also included the design of the tremie slab, thrust wall and design of the largely unreinforced launch shaft to resist asymmetric loading from partial ground freezing. The retrieval shaft was designed as a deep soil mixed shaft and is thought to be the deepest soil-mixed shaft in Miami. From a construction perspective, this paper discusses the unique challenges of building two shafts with two different techniques and will compare some of the constructability aspects, costs and equipment schedule-considerations related to the use of two separate techniques. INTRODUCTION Nicholson Construction Company (NCC) was awarded a $72.1 million Design-Build contract to replace an existing force main from the Virginia Key Central District Wastewater Treatment Plant (CDWWTP) under the Norris Cut Channel to Fisher Island. The location of the project is shown in Figure 1. The project involves replacing an existing 54-inch diameter pre-stressed concrete sewer force main with a 60-inch diameter fiberglass force main. Arup USA, Inc. (Arup) is the lead designer for Nicholson on this design-build project. Arup is providing design services for the TBM launch and retrieval shafts, segmental tunnel lining, the fiberglass pipe, and the horizontal directional drill component. Miami-Dade Water and Sewer Department currently owns and operates the existing 54-inch sanitary force main that transmits sewage collected from Miami Beach and Fisher Island to the CDWWTP for treatment and disposal. The existing force main was subject to a condition assessment in December 2011 which revealed structural deficiencies in the pre-stressed concrete pipeline."

Jan 1, 2016

By S. Dempsey

Since its passage in 1872, the Mining Law has been modified on several occasions to meet the changing needs of America's society and economy. Despite its evolution, the Mining Law continues to be criticized as outdated. This paper briefly traces the major points in the history and evolution of western mining laws, and reflects on the current status of ongoing discussion to reform the 1872 Mining Law.

Jan 1, 1997

By S. J. Schatzel, K. M. Ajayi, E. N. Rubinstein, Z. Khademian

This study simulates the impact of a shale gas well casing breach near a longwall mine. Field studies are conducted to measure mining-induced permeability changes over the abutment pillar of a longwall mine, and a geomechanical model is developed in 3DEC, a three-dimensional numerical modeling code, to predict the aperture of fractures in the overburden at the study site. The predicted aperture values are used to determine mining-induced permeabilities, and the results are compared with the field measurements. These aperture values are provided as inputs into fracture flow code (FFC), which generates a stochastic discrete fracture network (DFN) model for the study site and predicts the potential shale gas flow to the mine. Results from 100 DFN realizations are statistically analyzed using the bootstrapping method to compensate for notable variation in fracture geometry. The results show a significant difference between the gas inflow for nearby panels due to increase in the induced permeability during mining of the second panel. The average gas flow to the mine was calculated as 4.72 × 10 m3/s (49 cfm) for a hypothetical breach at the Sewickley horizon during the first panel mining, 8.97 × 10 m3/s (19 cfm) for a hypothetical breach at the Uniontown horizon during the first panel mining, 2.16 × 10 m3/s (458 cfm) for a hypothetical breach at the Sewickley horizon during the second panel mining, and 8.07 × 10 m3/s (171 cfm) for a hypothetical breach at the Uniontown horizon during the second panel mining. Depending on the mine ventilation system, this could result in methane concentrations exceeding regulatory limits. Hence, these findings provide insights into the potential risk of an unconventional gas well casing breach near a longwall mine under shallow cover.

Feb 1, 2024

By J-M M. Rendu

Geostatistics are increasingly recognized as powerful tools for reserve evaluation and grade control. It is also generally accepted that geologic input is required for the results of a geostatistical study to be meaningful. The role of the geologist is significant at all stages, whether it be to oversee the creation of the database, to assist in the statistical and semivariogran studies, to ensure appropriate block evaluation and kriging, or to review the results obtained. However the link between geology and geostatistics is often complex and not well understood. A presentation is made of the areas where geologic input is needed, and of the tools which the geologist should have at his disposition to ensure that his role is fulfilled. Organization of a Geostatisticel Study To be acceptable as the basis for financial investment, a geostatistical reserve estimation should be composed of four phases, the last phase being optional: Phase 1 - Background discussions, Phase 2 - Computation, Phase 3 - Reserve reporting, Phase 4 - Reserve audit. During the background discussions (Phase 1) the role of the geologist is primordial, as it is then that most decisions will be made concerning the geologic factors to be included in the geostatistical model.

Jan 1, 1985