Laserfiche WebLink
METHODS AND COSTS FOR STABILIZING FINE-SIZED MINERAL WASTES <br />by <br />K. C. Dean, ~ Richard Havens, ~ and M. W. Glantz <br /> <br />w <br />7 <br /> <br />i <br />i <br />t <br />C <br />./ <br />ABSTRACT <br />Fine-sized mineral wastes discarded 6y ore milling plants require stabi- <br />lization to prevent air and water pollution. Stabilization has been attained <br />by physical, chemical, vegetative, and combination procedures. Vegetative <br />reclamation is preferred to physical and chemical stabilization but is diffi- <br />cult to achieve because the wastes are sterile, contain deleterious inorganic <br />salts, and lack the essential nutrients and physical characteristics required <br />for sustaining vegetative growth. Methods now have been developed for attain- <br />ing vegetative growth on all but excessively acidic, basic, or saline tailings <br />at costs ranging from $120 to $650 per acre. The cost for stabilizing tail- <br />ings requiring more intensive treatment techniques may range upward to $1,750 <br />per acre. This report summarizes procedures developed by the Bureau of Mines <br />and industry for vegetating amenable tailings, lists costs for the various <br />processes, and suggests procedures that may be applicable for stabilizing <br />saline and pyrite-containing tailings. Ridged planting beds, drip irrigation, <br />and deep-furrow planting techniques are suggested for stabilizing saline <br />wastes. A combination of mill tailings and sewage sludge can be used for pro- <br />ducing synthetic soils, and layers of sewage sludge buried under a layer of <br />tailings offer promise of inhibiting acid formation from oxidation of sulfides <br />in mineral wastes. <br />INTRODUCTION <br />About I billion tons of mineral wastes are discarded annually in the <br />United States. Mineral waste piles currently cover over 2 million acres of <br />land. .These mineral wastes are second only to agricultural wastes in quantity <br />and represent over 30 percent of the total wastes produced in the United <br />States. Approximately 40 percent of the mineral discard is fine-size material <br />requiring some sort of stabilization if air and water pollution are to be min- <br />imized. On active mill tailing ponds, air pollution is controlled by keeping <br />the surfaces of the ponds wet either by tailings discharge or by sprinkling. <br />On inactive ponds, more lasting stabilization is required; physical, chemical, <br />vegetative, and combination methods for stabilizing tailings have been devel- <br />oped and are in use. <br />e <br />;. <br />i; <br />`Metallurgist. <br />2Chemist. <br />