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- Autorius: U S Department of the Interior
- Leidėjas: CreateSpace Independent Publishing Platform
- Metai: 2014
- Puslapiai: 56
- ISBN-10: 1496120981
- ISBN-13: 9781496120984
- Formatas: 21.6 x 28 x 0.3 cm, minkšti viršeliai
- Kalba: Anglų
Stream-Sediment Geochemistry in Mining- Impacted Drainages of the Yankee Fork of the Salmon River, Custer County, Idaho (el. knyga) (skaityta knyga) | knygos.lt
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Aprašymas
This reconnaissance study was undertaken at the request of the USDA Forest Service, Region 4, to assess the geochemistry, in particular the mercury and selenium contents, of mining-impacted sediments in the Yankee Fork of the Salmon River in Custer County Idaho. The Yankee Fork has been the site of hard-rock and placer mining, primarily for gold and silver, starting in the 1880s. Major dredge placer mining from the 1930s to 1950s in the Yankee Fork disturbed about a 10-kilometer reach. Mercury was commonly used in early hard-rock mining and placer operations for amalgamation and recovery of gold. During the late 1970s, feasibility studies were done on cyanide-heap leach recovery of gold from low-grade ores of the Sunbeam and related deposits. In the mid-1990s a major open-pit bulk-vat leach operation was started at the Grouse Creek Mine. This operation shut down when gold values proved to be lower than expected.
- Autorius: U S Department of the Interior
- Leidėjas: CreateSpace Independent Publishing Platform
- Metai: 2014
- Puslapiai: 56
- ISBN-10: 1496120981
- ISBN-13: 9781496120984
- Formatas: 21.6 x 28 x 0.3 cm, minkšti viršeliai
- Kalba: Anglų
This reconnaissance study was undertaken at the request of the USDA Forest Service, Region 4, to assess the geochemistry, in particular the mercury and selenium contents, of mining-impacted sediments in the Yankee Fork of the Salmon River in Custer County Idaho. The Yankee Fork has been the site of hard-rock and placer mining, primarily for gold and silver, starting in the 1880s. Major dredge placer mining from the 1930s to 1950s in the Yankee Fork disturbed about a 10-kilometer reach. Mercury was commonly used in early hard-rock mining and placer operations for amalgamation and recovery of gold. During the late 1970s, feasibility studies were done on cyanide-heap leach recovery of gold from low-grade ores of the Sunbeam and related deposits. In the mid-1990s a major open-pit bulk-vat leach operation was started at the Grouse Creek Mine. This operation shut down when gold values proved to be lower than expected.
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