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Effects of Small-Scale Gold Dredging on Arsenic, Copper, Lead, and Zinc Concentrations in the Similkameen River

Publication number Date Published
05-03-007March 2005
VIEW NOW Effects of Small-Scale Gold Dredging on Arsenic, Copper, Lead, and Zinc Concentrations in the Similkameen River (Number of pages: 47) (Publication Size: 481KB)

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Author(s) Johnson, A. and M. Peterschmidt
Description A field study was conducted to determine if small-scale gold dredges operating in the Similkameen River exacerbate current exceedances of the human health criteria for arsenic or result in violations of aquatic life criteria for arsenic, copper, lead, or zinc. Dredge effluents were analyzed from 14 sites on the river, and discharge plumes were sampled below three dredges. Results showed that the metals concentrations discharged from small-scale gold dredges are not a significant toxicity concern for aquatic life in the Similkameen and that it would take large numbers of dredges to effect a small change in the river’s arsenic levels, even at low-flow conditions.
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Keywords gold, results, river, toxic, zinc, dredging, copper, arsenic
WATERSHED Water Resource Inventory Area 49 Okanogan
DATA Environmental Information Management (EIM) #AJOH0045


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