Evaluation of the effectiveness of a desulphurized tailings cover at Detour Lake Mine
Date
2002
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Degree Level
Masters
Abstract
Cover technology has developed over the last decade as a remediation option to
reduce acid rock drainage from mine tailings. Desulphurized tailings have been
investigated as a cover material due to their potential to consume oxygen, hydraulic
properties and relative abundance at mine sites. A desulphurized tailings cover was
installed at the Detour Lake Mine to cover a portion of the tailings impoundment. The
desulphurized tailings cover was intended to reduce oxygen penetration into the
sulphidic tailings by maintaining saturation to reduce oxygen diffusion and by
consuming oxygen by oxidation of the remaining sulphide minerals. A research study
was initiated to evaluate the effectiveness of this cover at reducing oxygen penetration
into the sulphidic tailings.
The scope of the research involved a field investigation, laboratory analysis and
numerical modeling. The field investigation involved instrumenting the tailings
impoundment to measure weather data, water levels and water content. Tailings
samples were evaluated in the laboratory investigation for geotechnical and geochemical
characteristics.
The purpose of the field and laboratory investigation was to satisfy two objectives: to
yield qualitative conclusions regarding the effectiveness of the desulphurized tailings
cover and to establish representative profiles for the numerical modeling.
The purpose of the numerical modeling was to evaluate the oxygen concentration
through various tailings profiles to determine the relative effect of weather, vegetation and water table depth. The program SoilCover and a finite difference program were
used for this evaluation.
The general conclusion from this research was that the desulphurized tailings cover is
likely not reducing oxygen penetration into the sulphidic tailings to very low levels over
the entire tailings surface. The factors acting to reduce the oxygen penetration are the
ability of the sulphidic tailings to remain saturated well above the water table, the
consumption of a portion of the oxygen by kinetic oxidation and the potential, based on
field observations, for fine tailings layers within the tailings profiles to act as oxygen
barriers.
Description
Keywords
Citation
Degree
Master of Science (M.Sc.)
Department
Environmental Engineering
Program
Environmental Engineering