A major problem associated with reclamation of mined lands is toxic acidity and resulting solubilization of aluminum. These conditions are catalyzed by chemoautotrophic bacteria, including Thiobacillus ferrooxidans, during the process of sulfur oxidation. The resulting environment inhibits plant growth and also destroys heterotrophic bacteria populations which are necessary to enhance revegetation efforts as they fix nitrogen from the air, help aggregate soil and thus improve soil moisture conditions, prevent plant diseases, and control repopulation by acid-producing bacteria. Much research has been done to control acidification using substances that are bactericidal to T. ferrooxidans and the use of organic additives to increase soil fertility. This research is directed towards demonstrating the feasibility and benefits of combining (1) the methods for inhibiting acid- producing bacteria with (2) the methods for stimulating growth of heterotrophic bacteria to achieve long term reclamation success. Common chemicals, such as anionic surfactants, which have been proven to be bactericidal to T. ferrooxidans, will be used to control acid production. Commonly available poultry manure will be used to stimulate heterotrophic activity. The use of poultry manure will also help redistribute nutrients which are in excess at the place where they are produced, to another landscape position where they are severely limited.
Anticipated Results/Potential Commercial Applications of Research: This research will lead to an improved method for mine land reclamation at an increase in cost of 3- 5%. It will also result in a more environmentally sustainable distribution of plant nutrients. Excess nutrients produced by concentrated animal production units on one part of the landscape will be redistributed to mine lands that are generally severely nutrient limited. This integrated reclamation approach will enhance revegetation while preventing water pollution from acid mine drainage and excess nutrient runoff. In the USA, development of concentrated animal production units is rapidly increasing. There are also millions of acres of abandoned mined lands and active mining generates new lands, which must be reclaimed. The office of Surface Mining collects a tax of about $250 million a year for reclamation, which often does not achieve desired results. Mining companies spend an equivalent amount on reclamation and have difficulty in obtaining bond release. Success results will provide an integrated technology that will be embraced by both the mining industry and concentrated animal production facilities worldwide.
