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

Abstract

To evaluate the magnitude of, and change in, miningrelated 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 consensusbased 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.

Metal Content of Stream Sediments as a Tool to Assess Remediation in an Area Recovering from Historic Mining Contamination

“…Conversely, the T-test showed a significant difference in the Pb content between Turkey and Center Creeks (t = 0.04), which may reflect the immobile nature of Pb, which prevents Pb from distributing throughout the sediment, preserving the high and low concentrations near each other. Similar behavior of Pb has been reported by other studies within the TSMD [10,[17][18][19]. Compared to Center Creek, Turkey Creek sediments had larger standard deviation values, meaning that the metal content varied over a wider range of concentrations.…”

“…The disruption to sediments mentioned above consists of deposition of sediments resulting from leveling of land and application of new soil material, as dredging of stream sediments was not a part of the remediation action plan [21]. High variabilities in metal content in other streams within the TSMD have also been reported [10,[17][18][19].…”

“…In theory, the input of metals to the streams should decline with time in remediated areas [19]. This pattern is not yet evident at the TSMD.…”

“…In Aurora, the contamination of stream sediments is restricted to a short segment of the receiving stream [17], but some of the characteristics of TSMD streams remain, such as the variability and high metal content. Similarly, sediments re-sampled after a 13-year interval in the TSMD Cherokee County Superfund site (Kansas), showed metal concentrations increasing in some sites and decreasing in others [19]. Table 3 lists the metal content in sediments of Turkey Creek and Center Creek reported by selected studies [18,43,44].…”

“…Several studies assessing the effectiveness of remediation, e.g., variations of metal concentrations, have been conducted on all four TSMD Superfund sites as well as other TSMD sites [13][14][15][16][17][18][19]. These studies recognize that metal concentrations remain above toxic levels in sediments of some streams, reservoirs, and floodplain soils, and that the attainment of safe levels in sediments is a slow process [19]. In the Oronogo-Duenweg Superfund site, the major environmental threat consisted of toxic Cd, Pb and Zn in groundwater, soil and sediment [13,20].…”