Genesis of arsenic enriched groundwater and relationship with bedrock geology in northern Sweden
2012 (English)In: Metals and related substances in drinking water: Proceedings of the 4th International Conference, METEAU, LONDON: IWA PUBLISHING , 2012, 242-246 p.Chapter in book (Other academic)
A growing concern over incidents of widespread human exposure to arsenic (As) from groundwater sources has been noticed during the past three decades. Vaasterbotten county in northern Sweden hosts a large number of sulphide ore deposits and a number of gold deposits are recently discovered. Both are accompanied by elevated arsenic contents. Proterozoic metasediments sandwiched in the bedrock and mixed into the till contains elevated amounts of arsenic as well. During the present study about 80 groundwater samples were collected from dug wells, bore-wells and springs in the Skellefte field in Vasterbotten County in northern Sweden. Data from community environmental offices were also collected and included in the study. Arsenic concentrations were elevated in borewells and wetland springs while none of the dug wells had arsenic contents above 10 mg/l. The highest content seen in borewells was 300 mg/l and in wetland springs 100 mg/l. The As(III)/As(tot) varied largely in borewells while it was mostly above 0.8 in wetland springs indicating more reducing contents in the latter. The use of a redox classification indicated that two nechanisms were involved in the mobilisation of he arsenic, oxidation of sulphides and reduction of ferric oxyhydroxides. In some cases the borewells showed a mixed pattern, indicating inflow from different environments.
Place, publisher, year, edition, pages
LONDON: IWA PUBLISHING , 2012. 242-246 p.
IdentifiersURN: urn:nbn:se:kth:diva-119143ISI: 000314479600052OAI: oai:DiVA.org:kth-119143DiVA: diva2:610300
QC 201303112013-03-112013-03-072013-03-11Bibliographically approved