Reclamation of High-Elevation, Acidic Mine Waste with Organic Amendments and Topsoil

• Published in: Journal of environmental quality Vol. 31; no. 5; pp. 1528 - 1537
• Main Authors: Sydnor, M.E. Winter, Redente, E.F
• Format: Journal Article
• Language: English
• Published: Madison American Society of Agronomy, Crop Science Society of America, Soil Science Society 01.09.2002; Crop Science Society of America; American Society of Agronomy
• Subjects: Altitude; Applied sciences; Biomass; Conservation of Natural Resources; Decontamination. Miscellaneous; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Fertilizers; Gold; Hydrogen-Ion Concentration; Mining; Plant Development; Pollution; Pollution, environment geology; Soil; Soil and sediments pollution; Soil Pollutants - analysis; United States; North America; Colorado; America; USA, Colorado; Monocotyledones; Organic matter; Toxicity; Revegetation; Biomass; Compositae; Sewage sludge; Amendment; Absorption; Gramineae; Dicotyledones; Achillea millefolium; Angiospermae; Ecological recovery; Compost; Land reclamation; Heavy metal; Industrial waste; Phytotoxicity; Old mine; Spermatophyta; Performance; Soil plant relation; Dactylis glomerata; Mining waste
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2002.1528

The Summitville Mine was a high-elevation (3500 m) gold mine in southwestern Colorado. The mine was abandoned in 1992, leaving approximately 200 ha of disturbance comprised partially of an open pit, a cyanide heap leach pad, and two large waste rock piles. Reclamation of these mine facilities is challenging due to extreme climatic conditions in conjunction with high acid-production potential and low organic matter content of waste materials on site. In addition, stockpiled topsoil at the site is acidic and biologically inactive due to long-term storage, and may not be suitable for plant growth. The purpose of this study was to evaluate the effects of organic amendments (mushroom compost vs. biosolids) and topsoil (stockpiled vs. nonstockpiled) on aboveground biomass and plant trace element uptake. An on-site field study was established in 1995 to identify the most effective combination of treatments for successful reclamation of on-site waste rock materials. Incorporation of organic matter significantly increased aboveground biomass, with mushroom compost being more effective than biosolids, but did not significantly influence trace element uptake. Conversely, the use of topsoil did not affect aboveground biomass, but did influence trace element uptake. Treatments that received topsoil supported plant growth with significantly higher trace element tissue concentrations than treatments that did not receive topsoil. In general, it was found that waste rock could be directly revegetated when properly neutralized, fertilized, and amended with organic matter. Additionally, stockpiled topsoil, when neutralized with lime, supported plant growth equivalent to that on nonstockpiled topsoil.