The brine underlying the Oak Ridge Reservation, Tennessee, USA: characterization, genesis, and environmental implications

SURFACE STRUCIVRES:ENVIRONMENTAL ground water from mining is referred to as the probable hydrologic consequences (PHC) determination of mining and reclamation. This paper discusses the present day requirements and methodology of preparing a PHC for a large mining operation in the eastern coalfields. (from Authors) %g307 Ejector feat M. Preene, Ground Engineering, 29(4), 1996, p 16. In recent years ejectors (also known as eductors) have become available as an alternative pumping method capable of developing vacuums of up to 0.95 Bar in the well; this high vacuum makes them very effective in low permeability soils. An ejector system operates by circulating clean water at high pressure through a nozzle and venturi arrangement in each well; the water passes through the nozzle at high velocity which generates a low pressure zone which draws groundwater into the well to combine with the circulation water and be lifted out of the well. In simple terms an ejector is a water jet pump; no moving parts are located down the well and although water is injected into the well we get out more water than we put in. (from Author) 968308 The brine anderlying tbe Oak Ridge Reservation, Tennessee, USA: characterization, genesis, and environmental impllcatlons IZ-Z-7N;o~, Geochimica et Cosmochimica Acta, 60(S), 1996, pp The deep hydrogeologic system underlying the Oak Ridge Atomic Reservation contains brine. Its origin was assessed using existing and newly acquired chemical and isotopic data. The proposed model which best tits the data is modification of residual brine from which halite has been precipitated. Potential sources for this brine are in the Appalachian Mountains in the east. Other models, such as ultrafiltration and halite dissolution, were also evaluated. In places, contaminants such as radionuclides, heavy metals, nitrates, and organic compounds have reached the deep system. Observations suggest that whereas the origin of the salts in the brine may be very old, influx of recent water takes place. Consequently, the brine is not isolated from the overlying active and fresh-water-bearing units. (from Author) 968309 Water qoality impacts from mining in the Black Hills, south Dakota, USA P. H. Rahn, A. D. Davis, C. J. Webb & A. D. Nichols, Environmental Geology, 27(l), 1996, pp 38-53. The focus of this research was to determine if abandoned mines constitute a major environmental hazard in the Black Hills. Many abandoned gold mines in the Black Hills contribute acid and heavy metals to streams. In some areas of sulfide mineralization local impacts are severe, but in most areas the impacts are small because most ore deposits consist of small quartz veins with few sulfides. Pegmatite mines appear to have negligible effects on water due to the insoluble nature of pegmatite minerals. Uranium mines in the southern Black Hills contribute some radioactivity to surface water, but the impact is limited because of the dry climate and lack of runoff in that area. (Authors) 968310 Concentrations of contaminants in surface water samples collected In west-central Indiana impacted by acidic mine drainage S. K. Allen, J. M. Allen & S. Lucas, Environmental Geology, 27(l), 1996, pp 34-37. The results of analyses of surface waters collected from a variety of locations in west-central Indiana indicate extensive contamination by acidic mine drainage. These samples had pH values as low as 2.1 and total iron concentrations as high as 1200 mg I-‘. The speciation of iron, expressed as the ratio [Fe(II)~e(III)J ranged from 0.08 to 8.27. Measured lead concentrations were as high as 811 mg I-‘. In addition, the

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concentrations of nitrate and sulfate ions were as high as 359 and 624 mg l-‘, respectively. (Authors) 968311 Ground-water, surface water, and bottom-sediment contamination in the 0-fleld area, Aberdeen Proving Ground, Maryland, and the posslbie effects of selected remedial actions on groond water D. A. Vroblesky, M. M. Lorah & J. P. Oliveros, US Geological Survey Water-Supply Paper, 2399, 1995, 95 pp. O-field, in the Edgewood area of Aberdeen Proving Ground, Md., was periodically used for disposal of munitions, waste chemicals, and chemical-warfare agents from World War II to at least the 1950’s. This disposal has resulted in contamination of ground water, surface water, and bottom sediment at the site. Assessment was performed on such remedial actions as an impermeable cap, subsurface barriers, a groundwater drain, pumping, excavation, and no action. A digital three-dimensional ground water flow model was used to assess possible effects of the remedial actions. Each remedial action examined has advantages and disadvantages. (from Authors) 968312 Primary minerals of Zn-Pb mining and metallurgical dumps and their environmental behavior at Plombieres, Belgium H. Kucha, A. Martens, R. Ottenburgs, W. De Vos & W. Viaene, Environmental Geology, 27(l), 1996, pp 1-15. The primary phases and minerals of the Plombieres dumps include typical smelting furnace products such as metallic Fe, Pb, Cu, Zn, Fe-Zn alloys, carbides, phosphides, sulfides of Fe, Zn, Pb, Cu, Mn (alabandite), and FeAs. Spinels, mainly of Fe and Al, are common constituents of the primary assemblages; substitution by Zn, V, Cr, Ti, Mg, and Ca occurs. Leaching tests carried out on the surfaces of polished sections indicate that acid rain will mobilize mainly Zn and Cd and, to a much smaller extent, Pb and Sb. Leaching of metals by sulfate-chloride fluids present in the pore network of dumps depends on the pH, which in the dumps is controlled bv the urouortion of carbonates to sulfides. The more acid fluids ‘l&h both sulfides and silicates. (from Authors) 968313 Zusammensetzung, Verwittenmg, Sickerwasserberscbaffenheit und Sanlerwgsmogllcbkelten von Halden aos der Biel-/Zinkerzaufberelttmg am Belspiel der Unteren Labn (Structure, decomposition, drainage water qnallty and restoration possibilities of spoil heaps from lead and zinc processing in tbe lower Labn) G. Wieber & K. Knoblich, Mainzer Geowissenschaftliche Mitteilungen, 24, 1995, pp 181-200. The Romans mined, dressed and smelted lead and zinc in Germany. Mining and mass displacement produce irreversible changes of environment. Water leakage and geochemical reactions mobilize heavy metals and sulphates. These emissions are to be recognized a long time after termination of mining. (English summary) 968314 Decline and pall ANON, Ground Engineering, 29(4), 1996, p 17. Dewatering is proving key to Trafalgar House Construction Mining Company’s ElOM proposal to take over and restart construction of an access decline into the Bamnet Narong potash mine in Thailand. Work at the mine stopped in 1983 when a brine aquifer at around 60 m depth was intercepted, causing floods. The dewatering scheme will depressurise the aquifer zone around the drift, which will additionally be protected by grouting works carried out from both the surface and within the partially constructed decline. Dewatering consists of 20 main wells surrounding the zone where the drift passes through the brine stream horizon. The wells will be drilled using 128 mmID casing to 57.5 m depth, and