Modelling storage behaviour in a fractured rock mass

Modelling storage behaviour in a fractured rock mass

244A UNDERGROUND EXCAVATIONSRADIOACTIVE 955339 Navio limestone mine J. Chadwick, Mining Muguzine, 171(5), 1994, pp 280-282. Mina Navio, mining lime...

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955339 Navio limestone mine J. Chadwick, Mining Muguzine, 171(5), 1994, pp 280-282. Mina Navio, mining limestone from beneath the Cerro Navio, lies some 130 km north of Santiago and supplies the La Calera cement plant, 16 km to the south. In general there is a shortage of economically viable limestone in Chile and the extraction of raw materials for industries such as cement manufacture is often somewhat different to that undertaken in other countries, namely large-scale quarrying. Mina Navio has been an innovative operation throughout its history. It was the first mine in Chile to use LHDs, and was one of the earliest on the whole South American continent to do so, and was the first mine in Chile to use Anfo. This innovative flair has largely been driven by the complex geological nature of the deposit with correspondingly high operating costs, which today are three to four times those of equivalent surface limestone operations. Today it is a highly productive sub-level stoping operation. (from Author)

955340 HerSingin sea&n vanhat kaivokset ja louhokset (The old mines and quarries of Helsinki metropolitan area) B. Saltikoff, I. Laitakari, K. A. Kinnunen & P. Givanen, (Geological Survey of Finland; Guide 35), ISBN (paperback) 951 690 540 4, 1994, 65 pp, map. Helsinki with its surrounding areas was an important mining area in the 18th and the 19th century. The iron mines in Sillbole and Hameenkyla were economically important, but in addition to them, iron ore was quarried in about 20 smaller mines and pits. The Halvik ‘silver mine’ in Laajasalo was the only known sulphide ore deposit within the area. Lime was burned on a small scale in medieval times, but the building of the Suomenlinna fortress, during the second half of the 18th century, heralded the start of a large lime industry. The most important lime quarries were in Vuosaari, where marble was taken for mosaics and building plates up to 1950’s and 1960’s, decades after lime burning finished. Granite and schist were also needed at the Suomenlinna fortress and other parts of the city. Granite for paving stones was quarried as late as 1960% in many places. In the guide book the locations of old mines and quarries of Helsinki metropolitan area are given as exactly as possible. In addition, geology, minerals, as well as the time and the scale of the activity of the deposits are described. (from English summary)

955341 India’s coal industry enters an era of expansion S. K. Chowdhary, Coal InternationcI, 243(l), 1995, pp 15-24. This major feature describes the contribution that Coal India, Limited is making to the production of coal. This Govemment-owned organisation operates mines in eight states, accounting for 90% of the total output of coal in the country. The author shows that more recently, the private sector has been given the opportunity to participate in coal production. (Author)

955342 Longwall mining in Australia 0. Krellis, Mining Engineering, 47(l), 1995, pp 46-49. Starts with the history of coal mining by the longwall method, first used in Australia in the 1960s. Continues with the improvements made throughout the following decades and makes recommendations for the development of this technique. Also included are statistics on all Australian mines using the longwall method. (S.E.Long)


General underground storage 955343 Spindletop salt-cavern points way for future natural-gas storage S. A. Shot& J. R. Neal, R. J. Solis & C. Oldham, Oil & Gus Journal, 92(37), 1994, pp 68-75. This article describes this US underground natural gas storage complex and related facilities. Operation of the salt dome storage provides extremely fast injection and withdrawal, allowing quick response to changing market conditions. Design of gas injection and withdrawal facilities, leaching plant and wells, piping and compressors, dehydration and heating, the station control system, emergency and safety systems, facility construction, commissioning, first year operating experience, and customer base are described. (J.M.McLaughlin) 955344 Regulatory, technical pressures prompt more US saltcavern gas storage T. F. Barron, Oil & Gus Journui, 92(37), 1994, pp 55-67. Discusses the role and operation of salt caverns for storage and supply of natural gas in the USA. Salt caverns are being used to provide a peak supply service, emergency supplies, balancing short-term load swings and to avoid pipeline imbalance penalties, and for spot-gas purchasing strategies. The unique properties of salt which make it ideal for storage are described together with salt cavern site selection criteria, cavern development and construction, sine, spacing, operating pressures, and well equipment. Conversion of existing brine or LPG caverns for natural gas storage is also described. (J.M.McLaughlin)

Radioactive waste disposal

955345 Modelling storage bebaviour in a fractured rock mass D. Bruel, M. C. Cacas, E. Ledoux & G. De Marsily, Journui of Hydrology, 162(3-4), 1994, pp 267-278. A transient model was used to represent single borehole injection tests in fractured rock masses, on the basis of a three-dimensional stochastic description of the fracture network and of the mechanical behaviour of the fractures. The rock matrix remains impervious and storage occurs in the fractures, with a nonlinear compliance effect depending on both fluid pressure and normal closure stress acting on the joints. The aim of the study is to show how the shortest, weakly connected joints can be removed and replaced in the system by an equivalent parameter. (from Authors) 955346 Effects of thermally generated convection on the migration of radionuclides in saturated geologic formation H. D. Nguyen, S. Paik 8z A. S. Rood, Znternutional Journal of Engineering Science, 32(10), 1994, pp 1605-1614. The problem of radionuclide migration in the presence of simultaneous forced and free convection in parallel flows is studied numerically by a hybrid spectral numerical technique. In this method, the momentum, energy, and mass conservation equations together with Boussinesq approximations are solved using a combined Gale&in and collocation method in conjunction with the backward Euler for time integration. The results indicate that the actions of the buoyancy force are either to aid to oppose the main flow which can lead to an