Fig. 1. Water-extractable, exchangeable, weak acid–extractable, and toxicity characteristic leaching procedure (TCLP) Cd, Pb, and Zn from alluvial tailings deposits along the Upper Arkansas River, Leadville, CO, before and for two years after amendment with municipal biosolids (224 Mg ha^–1) and agricultural limestone (224 Mg ha^–1). Bars represent standard error of the means.