Remediation scenarios for selenium contamination, Blackfoot watershed, southeast Idaho, USA

Ecology and Biotechnology of Selenium-Respiring Bacteria

“…High rates of embryonic deformities and deaths in waterfowl and other wildlife due to Se contamination were recorded in the Kesterson National Wildlife Reservoir in California. Excessive phosphate mining activities in the Blackfoot River Watershed in Idaho have substantially increased the selenium levels in the river (8). The reductive microbial selenium transformations of the selenium cycle, which converts water-soluble and toxic selenium oxyanions (SeO 4 2Ϫ and SeO 3 2Ϫ ) into sparingly soluble elemental selenium or metal selenides, are the basis of promising approaches to bioremediation (5,9,10).…”

Regional scale selenium loading associated with surface coal mining, Elk Valley, British Columbia, Canada

“…Fish tissue concentrations of Se have been documented which led to the issuance of state advisories against excessive fish consumption by humans (Palmer et al, 2010). Surface phosphate mines in the American West have also led to downstream Se concentrations in excess of water quality standards (Myers, 2013). While reclamation practices have been found to reduce Se concentrations in streams draining older mines, the Se concentrations are still significantly elevated with respect to reference conditions (Lindberg et al, 2011).…”

“…Considerable research has been done on the downstream water quality impacts resulting from surface mining for various minerals, including coal (Griffith et al, 2012), uranium (Muscatello and Jans, 2009), and phosphate (Myers, 2013). Lindberg et al (2011) found that the concentrations of a number of trace metals, including Se, increased with the proportion of mined area draining to the stream.…”

Selenium in the upper Blackfoot River watershed, southeastern Idaho, 2001-12

“…The Wells Formation underlies the Phosphoria Formation and is the primary regional aquifer in the Blackfoot River watershed. The Wells Formation with its lithology of dolomite, limestone, and sandstone is more permeable than the Phosphoria Formation with its less permeable shales (Ralston and Williams, 1979;Ralston and others, 1980;Myers, 2013). The low permeability of the Phosphoria Formation contributes to long and complex groundwater-flow systems, including interbasin groundwaterflow systems.…”

“…Groundwater selenium concentrations in the vicinity of the North Maybe Canyon mine were noted to be generally increasing as of 2012, even though mining had ended by 1993 (Lee, 2001;Ecology and Environment, 2013). Groundwater fluxes to the Blackfoot River were estimated to require as many as 80 years to approach steady state, based on a conceptual model of groundwater transport of selenium (Myers, 2013). 11).…”