GEOSCAN, résultats de la recherche


TitreArsenic speciation in mine tailings and co-existing pore water, Lower Seal Harbour Gold District, Nova Scotia, Canada
AuteurDaniels, C; Parsons, M; Jamieson, H; Hall, G
SourceProceedings of the 9th International Conference on Acid Rock Drainage; 2012 p. 1-12
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110327
Réunion9th International Conference on Acid Rock Drainage; Ottawa; CA; mai 20 - 26, 2012
MediaCD-ROM; numérique
Lat/Long OENS-62.0000 -61.5000 45.2500 45.0000
Sujetsexploitation minière; or; activités minières; résidus; analyses des résidus; géochimie des résidus; arsenic; géochimie de l'arsenic; arsénopyrite; fluides des pores; géométrie des pores; échantillons d'eau interstitielle; effets sur l'environnement; etudes de l'environnement; résidus miniers; dangers pour la santé; géologie de l'environnement; géochimie; Paléozoïque; Ordovicien; Cambrien
Illustrationslocation maps; plots; micrographs
ProgrammeGestionnaire de programme, Géosciences environnementales
Résumé(disponible en anglais seulement)
Environmental impacts from historical mining and milling of lode gold deposits in Nova Scotia include elevated arsenic (As) concentrations within the tailings and in downstream receiving environments. The Lower Seal Harbour Gold District (LSH) operated from 1904 to the mid-1940s and produced approximately 395,000 tonnes of tailings. This study examined As speciation in tailings and associated pore waters to better understand the processes that control the mobility of As from these mine wastes.
Within LSH, three geographically and geochemically distinct sample locations were chosen to collect tailings and pore waters, including (1) sub-aerially exposed tailings; (2) shallowly submerged tailings; and, (3) tailings that are present in the intertidal zone of Seal Harbour, 2 km downstream of the milling operations at LSH.
Arsenic is present in the tailings at Sites 1, 2 and 3 at maximum concentrations of 9,200, 12,000 and 1,040 mg/kg, respectively. Elevated concentrations of As corresponded to arsenopyrite-bearing sections of the tailings cores, or intervals with abundant As-bearing secondary phases. Pore water analyses indicate high concentrations of As and pH values from 6.2 to 8.0.
Results from this study have helped to clarify the environmental risks associated with these historical mine wastes, and will support better informed land-management decisions.