Evaluation of pulverized trommel fines for use as a soil amendment

Pulverized trommel fines collected from the City of Chicago’s municipal solid waste were applied as a soil amendment over a 2-year period to evaluate: (1) their effects on soil quality by measuring soil elemental concentrations, pH, organic matter and cation exchange capacity; (2) their potential for pathogen transfer. A secondary objective was to examine crop growth, yield and productivity. Total and fecal coliform, Enterococci, Escherichia coli, Staphylococci and Salmonella were below minimum detection limits in trommel fines. Trommel fines contained 894.5 ± 171.4 mg/kg Pb, and when applied at a rate equivalent to 9.95 mt/ha dry wt, resulted in a soil Pb concentration increase of 18.80 mg/kg, thereby limiting lifetime trommel fine application to 15.9 years before reaching the 300 ppm IEPA (USEPA) regulatory limit. Trommel fines were subjected to a shake extraction procedure and resulting leachate Pb samples were 88.7% below the IEPA (USEPA) regulatory limit (5 mg/l). For the first year, corn yield was significantly higher on soil amended with trommel fines than soil amended with inorganic nitrogen fertilizer. During the second year, soybean yield was significantly lower on soil amended with trommel fines than on soil amended with inorganic fertilizer due to lower plant population. Results of this study suggest that trommel fines can be land applied as a soil amendment if best management practices are followed.