Evaluation of streambed-sediment metals concentrations in the Spring River Basin, Cherokee County Superfund site, Kansas, 2017

To evaluate the magnitude of, and change in, mining-related contamination, streambed-sediment samples were collected from 30 sampling sites in the Spring River Basin in the Cherokee County Superfund site, southeast Kansas, in July and August 2017. The Cherokee County Superfund site is part of the Tri-State Mining District, an area that covers parts of Kansas, Missouri, and Oklahoma that was historically mined for lead and zinc. The sampling sites corresponded to 30 sites sampled in 2004 as part of a previous study.

Concentrations of cadmium, lead, and zinc in the 2017 streambed-sediment samples were compared with the 2004 concentrations and with available sediment-quality guidelines. Cadmium concentrations from 2004 and 2017 samples were not compared if both samples had concentrations less than the lower of the sediment-quality guidelines because of poor performance of cadmium replicate-samples analyses at lower concentrations. Streambed-sediment concentrations of cadmium, lead, and zinc in the 2017 samples compared to the 2004 samples were decreased by at least 20 percent at 12, 16, and 16 sites, respectively; increased by at least 20 percent at 2, 5, and 7 sites, respectively; and had less than a 20-percent change at 5, 9, and 7 sites, respectively. In 2017, cadmium, lead, and zinc concentrations exceeded general consensus-based sediment-quality guidelines at 17, 14, and 18 sites, respectively, compared to 19, 17, and 20 sites, respectively, in 2004. In 2017, cadmium, lead, and zinc concentrations exceeded Tri-State Mining District-specific sediment-quality guidelines at 12, 14, and 11 sites, respectively, compared to 16, 16, and 13 sites, respectively, in 2004. The highest 2017 concentrations of cadmium, lead, and zinc were measured at sites along Short Creek near Galena, Kansas.