ILLINOIS RIVER DREDGED SEDIMENT: CHARACTERIZATION AND UTILITY FOR BROWNFIELD RECLAMATION

Brownfield reclamation in some ways is similar to surface mine reclamation. The similarities are that in both cases there is a large area of once productive ground that was severely impacted as part of a no-longer active resource extraction or augmentation industry. The differences include possible toxic soils or substrate and generally a lack of nearby quality soil for the brownfields given their typically urban settings. In contrast, reclamation is now part of a surface mining permit, soils are stockpiled to be replaced after mining, or topsoil substitutes are located and approved to serve as a final cover at a mine site. Brownfields, however, are usually located in urban areas where topsoils are difficult to obtain and transport. We conducted a large field demonstration project involving a brownfield in Chicago that was reclaimed with dredged spoils from the Illinois River. Disposal of dredged spoil often presents a problem in and of itself, and utilization as a topsoil substitute presents several advantages. In the case of the Peoria River sediments, the chemical and physical attributes are generally favorable as a topsoil substitute. These sediments tend to be fine textured, Silty Clay Loams and Silty Clays with about 3-5% organic matter content. Metal content is typically elevated above reference soils, but is generally not a problem. This paper presents our experience with this reclamation approach.