Abstract |
Bottom sediments were collected from the Red Cedar River, above and below the wastewater discharge of a metal workings plant, from the Grand River, above and below the sewage disposal discharge of the City of Grand Rapids, Michigan, and from six lakes for metal activation studies. These sediments were equilibrated with Na3NTA and Na4EDTA for 1, 3, 6, 9, and 14 days and Grand Rapids sewage sludge was equilibrated with these solutions for one day to determine the amount of metals solubilized. Trisodium NTA nad Na4EDTA solubilized significant amounts of Ni and Zn, but only from sediments contaminated with high amounts of these metals. The amount of metal solubilization from sediments due to chelation with Na3NTA was not great enough to be a probable environmental threat under the conditions investigated. (Modified author abstract) |