Introduction Historic mining activities near Leadville resulted in deposition of mine tailings in the Arkansas River. Over the years, these high pyrite wastes have been eroded and redeposited along an 11-mile stretch of the river, contaminating a number of areas. The fluctuating water table has resulted in alternating reducing and oxidizing conditions. As a function of the fluctuating water table and the acidic conditions, Zn and Pb form soluble salts and wick to the soil surface during dry portions of the year. Mine tailings washed down and accumulated in deposits up to and exceeding 2'.
Deposits are toxic to riparian vegetation.
Contaminated soils, barren of vegetation, are highly susceptible to continued erosion by the river. To conduct an evaluation of the effectiveness of remediation practices. Biosolids Demonstration Biosolids have been used both alone and in combination with other materials to restore soils that have been disturbed by a wide range of activities including coal and gravel mining. Research has consistently demonstrated that biosolids are highly effective, in many cases more so than topsoil replacement, for restoration of disturbed ecosystems. In September 1998, plots were seeded with a mixture of native seed and ryegrass.