Case History of a Copper Mine Tailings Pond Reclamation in Ducktown, Tennessee

Cessation of mining operations in Ducktown, TN, left 800-900 acres of barren copper mine tailings. Revegetation activities had met with limited success. In 1998, efforts for revegetation of the tailings materials began anew. The objective of this case history is to provide insight into decision making processes which resulted in conversion of 800-900 acres of barren mine tailings into a vegetated, productive landscape. Phase 1 began with intensive analyses of the tailings materials. Acid-base accounting registered a generally neutral to alkaline pH. Scattered areas were more acid with pH values measuring as low as 1.9. Neutralization potential was adequate in most cases to counteract potential acid formation. Total elemental analysis indicated a maximum of 416 mg kg P (total) with essentially none plant available as measured by the bicarbonate P method. Utilizing these data, phase 2 was initiated with the installation of two one-acre plots with variables of 1) P treatments (0, 50, 100, and 200 lb acre), 2) biosolid/ non-biosolid applications, and 3) fescue/ legumes (birdsfoot trefoil, sericea lespedeza, Korean lespedeza, and Kobe lespedeza). Korean and Kobe lespedeza/fescue on biosolids with 100 lb P acre were most productive. Phase 3 was based on data from the test plots. An in situ treatment of 100 lb P acre and 2 tons acre lime (to counter random generations of acids) with no biosolids and additions of standard fertilizers were applied with incorporation to at least 6 inches. Korean and Kobe lespedeza along with Kentucky 31 tall fescue were planted along with sandy bluestem and switch grass. The warm season grasses (sandy bluestem and switch grass) that were included in the seeding mixture were successful in grass test plots on site. Additional