PARENT SESSION
PM13 - Selenium: Sources, Pathways, Receptors
Monday, 18 November 2002
8:00 AM to 6:30 PM
Exhibit Hall

(P333) Selenium in Water, Sediment, Plants, Invertebrates, and Fish from Streams in Southeastern Idaho.

Hamilton, S^*,1, Buhl, K¹, Lamothe, P², ¹ USGS, Yankton, SD² USGS, Denver, CO

ABSTRACT- Nine stream sites in the Blackfoot River watershed in southeastern Idaho were sampled in June 2000 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium and other inorganic elements were measured in these aquatic ecosystem components, and a hazard assessment performed on the data. Water quality characteristics were relatively uniform among the nine sites examined. Of the aquatic components assessed, water was the least informative, especially for selenium contamination because measured concentrations were substantially below the national water quality criterion of 5 g/L. In contrast, selenium and several inorganic elements were elevated in sediment, aquatic plants, and aquatic invertebrates from several sites suggesting deposition in sediments and cycling through plants and invertebrates. Only selenium was elevated to concentrations of concern in fish. A hazard assessment of selenium in the aquatic environment suggested low hazard at Angus Creek near the mouth, Trail Creek, upper Slug Creek, and Sheep Creek, moderate hazard at lower Slug Creek and lower Blackfoot River, and high hazard at upper East Mill Creek, lower East Mill Creek, and Dry Valley Creek.

Key words: selenium, mining, hazard, fish