Assessment of Selenium Levels in Water, Bottom Sediment, and Biota of Arkansas River in Southwestern Kansas


Start Date: 2005

End Date: 2007

Full Citation:

Kansas Department of Health and Environment, 2005 - 2007. $35,000. "Assessment of Selenium Levels in Water, Bottom Sediment, and Biota of Arkansas River in Southwestern Kansas." PI: D. Huggins.

Category:

  • Aquatic

Associated with the KU Field Station: No

Research Summary:

Selenium was the only trace constituent associated with irrigation drainage that was observed to be at elevated levels in water, bottom sediment, and biota within the Upper Arkansas River basin. Selenium is usually associated with the clay content in rocks and so high concentration of selenium is often found in shales. Cretaceous marine shales and limestone are exposed extensively in the watershed. Thus, the main natural selenium source is runoff from the shales. Selenium becomes concentrated along the Arkansas River due to evapotranspiration and leaching of selenium by irrigation.

The most recent studies related to selenium levels in the Arkansas River were performed by USGS in the late 1980’s and by KGS in the late 1990’s. Thus, there is a need to assess the current degree of selenium impairment in the upper Arkansas River and need for TMDL for selenium in this region.

This study assessed selenium levels in water, bottom sediment, and biota of the Arkansas River between Kansas-Colorado state line and Garden City, Kansas. We sampled the Arkansas River at sites near Lakin, Kendall, and Coolidge, KS in early September and in mid-December 2005 and both the Arkansas River and Shunganunga Creek in 2006. Seasonal and cross-media variability of selenium levels were evaluated, and stream water was analyzed for nutrients and chlorophyll a. Periphyton samples were collected from the dominant substrate of the river (sand).