The dynamics of oxygen transport into soil covered mining waste deposits in Sweden
2001 (English)In: Journal of Geochemical Exploration, ISSN 0375-6742, Vol. 74, no 1-3, 163-173 p.Article in journal (Refereed) Published
One important objective in covering sulphide mining waste deposits with soil layers is to reduce the transport of oxygen to the waste. Irregular, unexpected and significant peaks were recorded in oxygen concentrations in a covered waste rock dump. They initiated a series of internal gas pressure recordings that were carried out in three covered sulphide waste deposits - one tailings impoundment and two waste rock deposits. All are situated in Sweden. Significant pressure variations were found in the covered waste. Sudden changes in ambient air pressure resulted in corresponding variations in the dumps. During periods with stable air pressures, even gravitational pressure variations (tidal effects) were experienced. The amplitude is about half the corresponding external variation. Approximate calculations show that the pressure variations are too low to explain the experienced peaks in oxygen concentration. The pressure recordings have verified that the covers as a whole act as tight barriers and that oxidation of sulphides due to advective transport of oxygen is probably of little importance, at least if the imperfections in the covers are reasonably small. © 2001 Elsevier Science B.V. All rights reserved.
Place, publisher, year, edition, pages
2001. Vol. 74, no 1-3, 163-173 p.
Advective, Air pressure, Diffusion, Dry covers, Oxygen transport, Tidal effects
IdentifiersURN: urn:nbn:se:liu:diva-47172DOI: 10.1016/S0375-6742(01)00182-0OAI: oai:DiVA.org:liu-47172DiVA: diva2:268068