Waste for wastelands reclaiming taconite tailings basins with organic amendments.

Abstract

Taconite tailings basins cover 10,500 hectares in northern Minnesota. Since these tailings are primarily quartz and iron oxides, water quality has not been an issue, but establishing vegetation on the coarse fraction of the tailings has been a major problem. Reclamation rules require that (1) percent cover must equal 90% after three to five years (depending on slope and aspect), and (2) vegetation must e self-sustaining after ten years. Typical cover on coarse tailings, even after five years, has ranged from 40 to 60%. Despite repeated application of seed and fertilizer, less than 10% of he coarse tailings areas meet standards. Application of 10 to 90 mt/ha of various organic amendments, including: peat; yard waste compost; municipal solid waste compost; and paper processing waste; have been shown to dramatically affect vegetative success. Although plots that received 90 mt/ha of peat were the most successful in meeting the three-year standard, some of the plots with as little as 10 mt/ha of amendment produced 90% cover after five years. Application of 22.4 to 89.6 mt/ha of waste from paper manufacturing was also effective in meeting long-term reclamation standards. Data from these studies suggest that the application of 22.4 to 44.8 mt/ha ofmore » organic amendment will meet reclamation standards within five years, and will be no more costly than the industry's current unsuccessful practices, if the source of the amendment is within 100 km of the mining area. In the fall of 1997, the first full scale application of organic amendments was made.« less