Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia
Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2008-09-29 17:21:50.73 Anthropogenic and geogenic sources of arsenic (As) have been identified in mining-impacted soils from the Giant mine (1948-1999), NT and the North Brookfield mine (1886-1906), NS. Bot...
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ftqueensuniv:oai:https://qspace.library.queensu.ca:1974/1547 2024-06-02T08:12:19+00:00 Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia Wrye, Lori Ann Geological Sciences and Geological Engineering Jamieson, Heather E. 2008-09-29 17:21:50.73 7893642 bytes application/pdf http://hdl.handle.net/1974/1547 eng eng Canadian theses http://hdl.handle.net/1974/1547 This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. Soils Arsenic Giant mine Northwest Territories North Brookfield mine Nova Scotia arsenic trioxide gold roasting thesis 2008 ftqueensuniv 2024-05-06T10:47:32Z Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2008-09-29 17:21:50.73 Anthropogenic and geogenic sources of arsenic (As) have been identified in mining-impacted soils from the Giant mine (1948-1999), NT and the North Brookfield mine (1886-1906), NS. Both used roasting to extract gold from the arsenopyrite ore, decomposing it to As-bearing iron oxides (roaster oxides or RO) containing As, and releasing As3+-bearing arsenic trioxide (As2O3). Arsenic trioxide is considered highly soluble with the dissolved As3+ species being more mobile and toxic than other oxidation states. Soil profiles from the Giant mine show elevated As and antimony (Sb) at the surface (As=140-3300ppm) and decreasing concentrations with depth (As=22-600ppm). Surface soils contain anthropogenically-derived As2O3 identified using synchrotron methods (µXRD, µXANES) and environmental SEM. The persistence of As2O3 is attributed to Sb in As2O3 grains, dry climate and high organics in the soils. Anthropogenically-derived RO of maghemite (containing both As3+ and As5+) and natural arsenopyrite were observed. Sequential selective extractions (SSE) from surface soils show between 20% and 75% of As extracted in the crystalline iron-oxide phase is attributed to As2O3 and RO, while at depth As is bound by organics in the weaker leaches. North Brookfield mine soils show lower total As (2ppm to 45ppm) except near the roaster (4300ppm). No As2O3 was identified, probably due to the smaller scale and age of the mine, lower organic content and the lack of Sb. As-bearing phases include RO of hematite (As5+), As-rich rims on titanium-oxides, and As associated with clays and goethite. Adjacent to the roaster, SSE show As was also in the amorphous iron-oxide phase, also shown by As in arsenopyrite weathering rims. There are many differences between the North Brookfield and Giant mine soils including roasting techniques which produced different RO mineralogy, the scale of mining, climate, soil type, and the presence of ... Thesis Northwest Territories Queen's University, Ontario: QSpace Northwest Territories |
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Queen's University, Ontario: QSpace |
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English |
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Soils Arsenic Giant mine Northwest Territories North Brookfield mine Nova Scotia arsenic trioxide gold roasting |
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Soils Arsenic Giant mine Northwest Territories North Brookfield mine Nova Scotia arsenic trioxide gold roasting Wrye, Lori Ann Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
topic_facet |
Soils Arsenic Giant mine Northwest Territories North Brookfield mine Nova Scotia arsenic trioxide gold roasting |
description |
Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2008-09-29 17:21:50.73 Anthropogenic and geogenic sources of arsenic (As) have been identified in mining-impacted soils from the Giant mine (1948-1999), NT and the North Brookfield mine (1886-1906), NS. Both used roasting to extract gold from the arsenopyrite ore, decomposing it to As-bearing iron oxides (roaster oxides or RO) containing As, and releasing As3+-bearing arsenic trioxide (As2O3). Arsenic trioxide is considered highly soluble with the dissolved As3+ species being more mobile and toxic than other oxidation states. Soil profiles from the Giant mine show elevated As and antimony (Sb) at the surface (As=140-3300ppm) and decreasing concentrations with depth (As=22-600ppm). Surface soils contain anthropogenically-derived As2O3 identified using synchrotron methods (µXRD, µXANES) and environmental SEM. The persistence of As2O3 is attributed to Sb in As2O3 grains, dry climate and high organics in the soils. Anthropogenically-derived RO of maghemite (containing both As3+ and As5+) and natural arsenopyrite were observed. Sequential selective extractions (SSE) from surface soils show between 20% and 75% of As extracted in the crystalline iron-oxide phase is attributed to As2O3 and RO, while at depth As is bound by organics in the weaker leaches. North Brookfield mine soils show lower total As (2ppm to 45ppm) except near the roaster (4300ppm). No As2O3 was identified, probably due to the smaller scale and age of the mine, lower organic content and the lack of Sb. As-bearing phases include RO of hematite (As5+), As-rich rims on titanium-oxides, and As associated with clays and goethite. Adjacent to the roaster, SSE show As was also in the amorphous iron-oxide phase, also shown by As in arsenopyrite weathering rims. There are many differences between the North Brookfield and Giant mine soils including roasting techniques which produced different RO mineralogy, the scale of mining, climate, soil type, and the presence of ... |
author2 |
Geological Sciences and Geological Engineering Jamieson, Heather E. |
format |
Thesis |
author |
Wrye, Lori Ann |
author_facet |
Wrye, Lori Ann |
author_sort |
Wrye, Lori Ann |
title |
Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
title_short |
Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
title_full |
Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
title_fullStr |
Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
title_full_unstemmed |
Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia |
title_sort |
distinguishing between natural and anthropogenic sources of arsenic in soils from the giant mine, northwest territories and the north brookfield mine, nova scotia |
publishDate |
2008 |
url |
http://hdl.handle.net/1974/1547 |
geographic |
Northwest Territories |
geographic_facet |
Northwest Territories |
genre |
Northwest Territories |
genre_facet |
Northwest Territories |
op_relation |
Canadian theses http://hdl.handle.net/1974/1547 |
op_rights |
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. |
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1800758711150444544 |