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By Rob Boom, Yasuyuki Tozaki, Frank M. Wheeler

Selection of a suitable site for a metallurgical plant is crucial for the success of the business case. For a brownfield project, with the decision to locate the project on a site with existing production facilities and activities, the selection of the site has been made. For a greenfield project, important economic and logistical considerations include proximity to primary and secondary resources and/or to the market, infrastructure, and access to energy and water. National and regional aspects, including the social license to operate, can be decisive in final site selection. Key to recruiting and retaining a labour force are proximity to urban areas, along with weather and health conditions at the site. Risk factors include site geotechnical parameters and topography, contamination, as well as probability and types of potential natural disasters.

Jan 1, 2015

By Sheridan A. Glen

As the Federal government along with individual states continue to grapple with the job of refining a comprehensive energy policy, coal continually stands out as an energy source which heralds a combination of old and new capabilities like an energy planners prophecy, but which is plagued with serious environmental constraints. To determine what level of coal utilization is ultimately possible for states East of the Mississippi, whose high sulfur content coal presents the most paramount of challenges, one must consider product availability, via existing transportation modes, the developing industrial markets and the ability of coal to meet the challenge of becoming an environmentally acceptable fuel. Gasification is emerging as a form of utilization, which during the next twenty years stands a good chance of being able to meet the challenge of making coal an environmentally clean, easily transport-able and usable fuel. It can be argued that, of all the potential ways of utilizing high sulfur coal, coal gasification is perhaps the most expensive, the most financially risky and carries environmental liabilities of its own. Synthetic gas and oil markets will undeniably be a function of price and demand, which, for the purposes of this paper, I'm assuming will begin to merge in the late 1980's and into the 1990's. This is also presuming that public utility commissions will allow favorable price structure ruling so that gasified coal products can be rolled into their respective rate base, much the same as synthetic natural gas from petroleum by-products are currently being priced. The comparative economic markets of coal to gas pro-duct have plenty of time to mature. There is an approximate twelve-year lead time needed to bring coal gasification plants on line which will be able to compete in the market place for natural gas and oil customers.

Jan 1, 1977

By M. Kehnemuyi

The U.S. Department of Energy is charged, by federal law, with the responsibility for developing and implementing programs for long- term storage and terminal disposal of high- level radioactive wastes from both commercial and defense nuclear operations. Approximately 288,000 cubic meters of defense high-level wastes are currently in storage at the government's Hanford Reservation in the State of Washington, the Savannah River Plant in South Carolina, and the Idaho Chemical Processing Plant in Idaho (U.S. Department of Energy, 1980a). High-level wastes from commercial nuclear power production are stored in water pools or basins at various power plant sites. At the end of 1980, approximately 7.460 metric tons of uranium, contained within 28,300 fuel assemblies was in storage at various reactor basins. Although the present inventory of defense wastes are many times larger in volume and in total level of radioactivity than the commercial wastes, in the future, the latter will constitute a substantial quantity of wastes that will have to be disposed of. The present electric generating capactiy of nuclear power plants in the United States is 56.5 Gigawatts-electric (GWe). The amount of spent fuel that would be discharged and accumulated by the year 2000 from these operating reactors would be 38,000 metric tons. With a projected growth of the nuclear industry to 180 GWe in the year 2000, the amount of spent fuel accumulated at the turn of the century could reach 89,000 metric tons of uranium or approximately 318,000 assemblies. In any case, whether one postulates a no growth pattern or one where nuclear power provides its share in the country's electric generating capacity in the next two decades, a means for safe and environmentally accept- able disposal of high-level nuclear wastes must be found. Storage of commercial wastes in water basins, either at reactor (AR) sites or at away from reactor (AFR) sites, and storage of reprocessed defense wastes in surface or near surface tanks is a temporary solution and is not an alternative for permanent disposal.

Jan 1, 1981

By Paolo Heiniger

The aim of this paper is to present the operative solutions devised and then adopted to implement the underexcavation (soil extraction) of the Tower of Pisa, by means of soil extraction. The intervention has been performed by the Consorzio Progetto Torre di Pisa, a joint venture made of five qualified Italian companies (Trevi S.p.A. , Rodio S.p.A., Italsonda S.p.A., Ismes -Enel Hydro S.p.A., Bonifica S.p.A.), selected for their experience in the field of monitoring and restoration of monuments, structural design, foundation engineering and specialised works in underground conditions. Since 1991 the Consorzio has been charged with the specific task of implementing, within the contractual frame of a Concession, all the decisions made by the International Multidisciplinary Commission appointed by the Italian Government the previous year, with the aim at solving the «problem» of the Tower, strengthening the structure and stabilising its foundation. The Trevi Group, which is represented by Trevi S.p.A. in the above mentioned Consorzio, has given and is giving its direct and constant contribution and is engaged in supplying the special equipment to the operation and the drilling technology which has been successfully adopted to date.

Jan 1, 2000

By K. M. Kim

A site-specific blasting model has been developed for the Asarco Mission mine. The main inputs to the model are the in-situ block size (F80), the post-blast fragmentation (P80) and the intact tensile strength (To). The output from the model is the specific blast energy (ESE). Modern techniques are being used to obtain the input parameters for the site-specific blast fragmentation model. In particular, image processing software is used to obtain both the in-situ block size and the post-blast fragmentation, and the Schmidt hammer is used to obtain the tensile strength at numerous locations throughout the rock mass. An initial model was developed using five test shots in one area of the mine that contains Argillite and is relatively homogeneous. This also included calibrating Schmidt hammer readings against actual Brazilian tensile measurements. The model for Argillite will be updated as more tests are conducted, and the model will be extended to the other four primary rock types at the Asarco Mission mine.

Jan 1, 2011

By K. M. Kim, J. B. Kemeny

A case study was conducted with 5 shots with varying pre-blast block sizes and explosive energies. From this case study a site-specific predictive fragmentation model was developed. There are two main innovations in this study. One is using an image analysis program (Split-Desktop 3.0) on the bench face to obtain the pre-blast block size (F80) quickly and consistently. Another innovation is to utilize the Schmidt Hammer Hardness (SHH) to estimate intact rock strength.

Jan 1, 2011

By Ambarish Ghosh, Chitralekha Ghatak, Tanumaya Mitra, Tarun Sengupta, Sajib Das, Sankar Kumar Nath

"Currently construction of important structures like bridges, flyovers and high rise buildings in and around Kolkata are in full swing. These structures have mostly pile or well foundations. The design methodology and construction techniques are being employed keeping in view both the safety and economy of the project. The data presented in this investigation have been taken from Geotechnical Investigation report of Component B in connection with construction of Extradosed Cable Stayed Bridge over River Hooghly in Hooghly and Nadia district of West Bengal, India. The investigation site is located within close proximity of Eocene Hinge Zone which is being taken as the principal contributor of Earthquakes in and around Kolkata. Considering the importance of the project detailed and exhaustive geotechnical investigation has been carried out and site specific response spectra have been generated for analysis and design of the bridge. This paper presents site specific response spectra, liquefaction analysis and comparison of lateral load carrying capacity of pile using Winkler approach and IS 2911 guidelines.INTRODUCTIONPile foundations are used to transfer the load of the super structure through soft soil deposit to deeper bearing stratum by means of skin friction or end bearing or both. Pile foundations are regarded as a safe alternative for supporting structures in seismic areas and have been used for this purpose in non-liquefying as well as liquefying soils. But their design in case of potentially liquefiable soil is quite different from that of non liquefiable soil. In liquefiable soil the progressive buildup of excess pore water pressure will cause stiffness degradation and loss of strength which in turn will induce additional shear force and bending moment in the pile. The mechanism of pile behavior in liquefying soil has been investigated by several investigators in the recent years based on observations of pile performance during earthquakes and studies in the centrifuge and Shake Table tests. Exhaustive geotechnical investigation has been carried out along the proposed alignment of the Extradosed Cable Stayed Bridge i.e., along Baropara, Bansberia ROB, Ishwar Gupta Bridge, Saraswati River to collect disturbed as well as undisturbed soil sample, to develop average soil profile and to determine the design parameters. The proposed project site is very close to Eocene Hinge Zone, which is basically a strike slip fault, capable of generating an earthquake of Mw 6.7. Thus it is evident that the proposed Bridge needs to be designed considering the adverse geo-hydrological condition as well as the earthquake aspects needing special attention following the state-of-the-art technology as guided by relevant codes and published literatures. Considering the soil profile of these locations ground response analysis has been carried out using equivalent linear method to determine the site amplification. Site specific response spectra have been developed for the four zones and zone factors have been determined. The computed zone factors are 0.198g, 0.195g, 0.195g and 0.20g for the four zones respectively, much higher than the zone factor 0.16g, which is for zone III, as stipulated in IS 1893:2002."

Jan 1, 2015

By KNona C. Liddell

Goethite is an important naturally occurring sorbent for divalent heavy metals and has often been used as a model compound in studies of adsorption on oxide mineral surfaces. Surface complexation modeling, surface spectroscopy, and electrochemical techniques have all been applied to goethite adsorption. Modeling studies have shown that usually several different sets of fitted parameters are equally successful in representing surface charging and adsorption data. Surface spectroscopic data are proving valuable in determining the nature of the surface sites, and refined models now incorporate structural information on interatomic distances and coordination numbers. Multisite surface complexation models can give very good fits to surface charging and adsorption data, but further improvements are needed to better represent surface reactions involving exchange of protons and divalent cations. Recent experimental and modeling studies on adsorption of divalent transition metals on goethite are described and the present status of the field is assessed.

Jan 1, 1999

By R. L. Loofbourow, Robert R. Miller

Deep, stable, unlined space promises secure, efficient, acceptable solutions to several current problems. With truly favorable conditions, it can be economic as well. The basic requirement is sufficient sound, tight rock at required depth. This and unusual surface requirements point to special testing. An objective is to describe conditions for planners, estimators and contracts. A first stage concept study needn't be prolonged but should overlook nothing significant. Although observations and tests on core are considered essential, time and expense can be cut by supplementing then with tests on walls of rotary or percussion holes. In some places initial drilling could be shallow.

Jan 1, 1981

By Norman D. Harte, George W. Holl

The development of the most important tool used in Site Testing is reviewed briefly and the application of the information gained is described. The operation of Site Testing and pregrouting of underground excavations is dealt with in detail. Practical experiences (and pitfalls into which the inexperienced might fall) are recorded. But for the application of Site Testing and grouting of shafts, tunnels and other excavations, vast areas of the present goldfields in South Africa would remain unexploitable.

Jan 1, 1981

By S Hawker, M Gibbs, A Craven

Current climate change projections suggest both an increase in the intensity of significant rainfall events and an increase in the variability of rainfall in some regions of Australia. It is necessary for mine site owners and operators to understand the effects that this potential shift in climate may have on their operations. The ability to maintain compliance with discharge regulations and operational security for those sites that rely on surface water run-off harvesting may be negatively impacted if some current climate change projections are realised. Although current regulations require the preparation of water management plans, these are generally developed using historical climate records for the site in question and as such do not give any indication of a siteÆs resilience to the influences of climate change.This study compares design and operational considerations for a case study mine site using historical rainfall records and modified records representing climate change projections. The future climate models are invariably broad scale and are limited in their capacity to be downscaled to a reasonable resolution for developing a site water balance. Instead the local historical data set has been modified to concentrate precipitation to peak periods and propagated through the model. The study looks at the siteÆs response to the potential changes in climate.It is shown that if current climate change projections are realised, this will have a significant effect on both the necessary size of designed surface water infrastructure and operational considerations on-site. A discussion is presented on the potential risks that climate change presents to mine sites and the range of options that could be considered to mitigate these risks. Depending on a number of factors, including location and risk profile of the owner/operator, resilience to climate change can be addressed as either a capital or operational expenditure (CAPEX/OPEX).CITATION:Craven, A, Hawker, S and Gibbs, M, 2013. Site water balance response to variable climatic conditions, in Proceedings Water in Mining 2013 , pp 211-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Kioshi Mishiro, Pratima Jauhari, Walter Williams

INTRODUCTION The UN-General Assembly adopted an Agreement on 28 July 1994 entitled ‘Agreement relating to the implementation of Part XI of the United Nations Convention on the Law of the Sea ((UNCLOS) of 10 December 1982’. The Agreement came into force on 16 November 1994, and consequently, the inauguration of the International Seabed Authority (ISA, or the Authority), located in Kingston, Jamaica. The Authority is the organization through which States Parties to the Convention (168, as of 25 July 2017) shall, in accordance with the regime for the seabed and ocean floor and subsoil thereof beyond the limits of national jurisdiction (the Area) established in Part XI and the Agreement, organize and control activities in the Area, particularly with a view to administering the mineral resources of the Area. The legal regime for the administration and development of the mineral resources of the Area as it now exists are available in Part XI of the Convention1 which contains the legal framework governing “activities in the Area” and in Annex III to the Convention which contains the “Basic Conditions of Prospecting, Exploration and Exploitation” with respect to the resources of the Area2. The 1994 Agreement relating to the Implementation of Part XI of the UNCLOS is the so- called ‘parallel system’; as elaborated in article 153 of the Convention. The essential elements of the ‘parallel system’ include assured access for States parties and their nationals to seabed mineral resources along with a system of site-banking, whereby ‘reserved areas’ are set aside for the conduct of activities by the Authority through the ‘Enterprise’ itself or in association with developing States or in joint venture with the contractor who provided the particular reserved site2.

Jan 1, 2018

By J. Kemeny, K. M. Kim

A site-specific blasting model has been developed for the Asarco Mission mine. The main inputs to the model are the in situ block size (F80), the post-blast fragmentation (P80) and the intact tensile strength (To). The output from the model is the specific blast energy (ESE). Modern techniques are being used to obtain the input parameters for the site-specific blast fragmentation model. In particular, image processing software is used to obtain both the in situ block size and the post-blast fragmentation, and the Schmidt hammer is used to obtain the tensile strength at numerous locations throughout the rock mass. An initial model was developed using five test shots in an area of the mine that contains argillite and is relatively homogeneous. This process also included calibrating Schmidt hammer readings against actual Brazilian tensile measurements. The model for argillite will be updated as more tests are conducted, and the model will be extended to the four other primary rock types at the Asarco Mission mine.

Jan 1, 2011

In order to analyze and quantify distinct environmental properties in the vicinity of sites, the Site-Specific Natural Resources Information System (SARIS) has been developed based on a Geographic Information System (GIS). SARIS is one of the fundamental databases of a collaborative research program aiming at the resource orientated analysis of metallic raw material flows with aluminum and copper serving as exemplary case studies. The spatial database incorporates all present production sites of ore extraction, refining and smelting. Environmental data for each location were derived from global digital survey data covering land cover, soils, morphology, climate, topography and population density. The main application of this database is the characterization of environmental safeguard objects, which may be affected by the activity of concern. This site-specific environmental impact assessment is used to determine the relevance of environmental issues based on the distribution pattern of sites in a global framework. The derived results are used to suggest a tailored indicator approach to measure progress and performance of industrial developments relative to the predetermined site-specific conditions.

Jan 1, 2003

By Phillip R. Moyle

A cobalt/manganese occurrence in Clark County, Nevada was the subject of a site-specific mineral investigation by the U.S. Bureau of Mines in 1988-90. The study site is in the northern part of the Million Hills (wilderness) study area which is administered by the Bureau of Land Management. Field work during a period of one week consisted of geological mapping and sampling of workings and outcrops, and geochemical and geophysical surveys conducted on four transects totalling 7,600 ft. Although the concentrations of cobalt (0.1 to 0.5 percent) detected in samples from the fissure zones are within the range of grades associated with world-class economic deposits, the volume of material enriched in cobalt at the study site is insufficient to warrant consideration as a potential resource. Concentrations of manganese, nickel, copper, lead, zinc, barium, and thallium, although anomalous, are too low for economic consideration. At the study site, workings consist of three trenches and nine pits. The exploration history is unknown, and no production is reported.

Jan 1, 1990

By S. A. Shoop, J. J. K. Daemen

Site-specific blast vibration prediction can be more accurate than using a universal prediction equation. Vibrations from 37 blasts were monitored using three seismographs. Data analysis showed that square root, cube root, and site-specific scaling predicted ground motion with equal reliability. Imprecise prediction is caused by geologic and blast variability, particularly, inaccurate delay times. Vibrations at some mines were consistently lower or higher than vibrations predicted from US Bureau of Mines (USBM) equations. Vibration restrictions based on USBM studies could then be too conservative or too lenient. Predominant vibration frequencies were generally less than 50 Hz, but several blasts had significant energy up to 125 Hz. In some cases, energy was concentrated at frequencies corresponding to delay intervals.

Jan 1, 1985

By S. A. Shoop

Vibrations from thirty-seven blasts were monitored using three seismographs. Data analysis showed that square root, cube root, and site-specific scaling predicted ground motion with equal reliability. Imprecise prediction is caused by geologic and blast variability, particularly inaccurate delay times. Vibrations at some mines were consistently lower or higher than vibrations reported in the U.S. Bureau of Mines studies. Regulations based on USBM data could then be too conservative or lenient. Predominant vibration frequencies were generally less than 50 Hz, but several blasts had significant energy up to 125 Hz. In some cases energy was concentrated at frequencies corresponding to delay intervals.

Jan 1, 1983

By Steven G. Vick

Not too long ago a mill superintendent, when asked where his tailings were being disposed, could simply shrug his shoulders and point to the open end of the thickener discharge pipe. This “out of sight, out of mind” approach to tailings disposal is a practice of the past. Today there are very few planned hardrock or energy-related mining facilities where tailings disposal has not been identified as the major area of impact and controversy. In fact, development of some ore bodies has been stymied altogether by lack of suitable sites or methods for tailings disposal. The bottom- Iine result is that tailings disposal often controls the permitting lead time and has a significant influence on construction cost (up to 2070 in some cases) of new minemill complexes. The following article, the first in a series of three, explores technical background and historical perspectives on siting and design of tailings impoundment facilities.

Jan 6, 1981

By William R. Barton

It is generally conceded as axiomatic that the aggregate producer and the average urban resident have mutually incompatible goals. The producer wants to be near his mass market and the average resident wants him as far away as possible. The traditional economic decision to mine local material to avoid transportation costs is increasingly challenged by zoning and planning bodies and by citizens' groups. This conflict generated much written and spoken word and offered opportunity for great flights of rhetoric. The pressure on the producer also has forced re¬appraisal of the need for the classic confrontation with indications that much of the conflict is more apparent than substantive. In New England several factors combine to increase complexity of the siting problem. It is a region of high land values and population density. Due to the proximity of metropolitan areas, even rural communities have experienced a prolif¬eration of environmental groups with concomitant enthusiastic regional planning and critical watch over land use. In New England where there is little public understanding of the necessity for, and the realities of, mineral production a sophisticated approach to aggregate production site location is required.

Jan 1, 1975

By William G. Wilson

In the U.S. today a number of tentative synthetic fuel plants have been sited by a number of major corporations. Each of these for a number of reasons have deferred construction. The only synthetic fuel plants under active development are those being built with the Energy Research and Development Administration (ERDA) under the authority of the Non-nuclear Energy Research and Development Act of 1974 (Public Law 93-577). Under this Act in joint sponsorship with industry, a series of coal conversion pilot and demonstration plants are being built to produce environmentally acceptable fuels from high sulfur coals. Before entering into a discussion of the factors associated with the siting of the ERDA coal conversion program, the difference between a pilot plant and a demonstration plant should be explained. The terms pilot plant and demonstration plant iridicate a size of plant rahter than technology. A pilot plant will vary from an "add-on" to an existing facility to an independent unit. Demonstration plants are a wholly independent, self contained plants, capable of independent operation to demonstrate the environmenta1, economic, and technica1 feasibility of a technology. These plants are from one-third to one-tenth the scale of a commercial operation and often described as plus 1000 tons per day of coal consumption. Their purpose is stated in the Act (Section 6, (3)(E),) "to accelerate the commercial demonstration of technologies for producing syncrude and liquid petroleum products from coal: Provided. That the Administrator shall invite and consider proposals from potential participants based upon Federal assistants and participation through guaranteed prices or purchase of the products .... " In site selection and plant design it has been suggested that special interest groups should be allowed to dictate the site and specify the design. Under the present program the industrial partner who is contributing 50 percent

Jan 1, 1977