Abstract
The Tri-State Mining District (TSMD) of Kansas, Missouri, and Oklahoma was a world class zinc (Zn) and lead (Pb) producer. Mining ceased in the 1950s, leaving behind a large amount of mine wastes. Although much of the affected areas have been remediated, stream sediments may still contain toxic levels of these metals. The mobility of the metals was determined for sediment samples from Turkey Creek, Missouri. The median values of the metal content were 2700 mg/kg Zn, 161 mg/kg Pb, and 10.8 mg/kg Cd. These concentrations marginally surpass the sediment quality guidelines that differentiate between toxic and nontoxic conditions. Mobility was determined by sequential extraction of two phases—bioavailable and Fe-oxides. The fraction of the metal available to biota was 7.7% for Zn, 5.0% for Cd, and 0.4% for Pb, whereas the Fe-oxide fraction retained 25% of Zn, 21% of Pb, and 35% Cd. These values roughly agree with the values reported for other areas of the TSMD. Fractionation provides an estimate of the amount of metal available at the present conditions and gives the amount of metal available should the pH and/or Eh vary. The methodology puts an emphasis on ecosystem health and can be applied to other areas where Zn–Pb concentrations in soils and sediments are a concern.
Highlights
Wastes from abandoned mines remain a contamination threat in many parts of the world [1,2]
Besides Zn and Pb, small amounts of other metals can be released from chat piles, including silver (Ag), cadmium (Cd), copper (Cu), and thallium (Tl) and metalloids such as arsenic (As)
The pH values of the water at the sample locations were all in the alkaline range, indicating that, unlike in the Oklahoma part of the Tri-State Mining District (TSMD) [8,25], acid mine drainage (AMD) in this part of the TSMD
Summary
Wastes (e.g., tailings or chat piles) from abandoned mines remain a contamination threat in many parts of the world [1,2]. Areas of mine tailings are a major source of contamination as they continue to release metals even after hundreds of years [3], making remediation a critical component of waste cleanup. Metals store in solid phases, e.g., soils and sediments. From the total amount of metal stored, a fraction will be available to biota and contribute to the toxicity threat to biota. Mobility reflects the easiness for a metal to be released into water and depends on the chemical bonds by which the metal is attached to different chemical phases in the sediment [6,7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
