Download or read book Evaluation of Passive Systems for the Treatment of Mine Drainage written by Heath Roscoe and published by . This book was released on 1999 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acid Mine Drainage (AMD) is a serious environmental problem and the focus of a great deal of research. Passive treatment systems associated with wetlands and Anoxic Limestone Drains (ALDs) provide a low-cost, low-maintenance treatment in contrast to continuous chemical metering. The ALD adds alkalinity to the water allowing for a more rapid formation of iron precipitates. The abiotic oxidation ponds associated with these systems are expected to precipitate about 10-20 g/sq m-day of iron. The focus of this research is to evaluate two different ALD passive treatment systems in order to find ways to improve the efficiency of the abiotic oxidation of ferrous, thereby reducing the amount of land area required to treat the discharge. The two systems evaluated differed in that one system is a channel system, while the other is a series of ponds. The channel system has a large excess of alkalinity while the pond system has net mineral acidity. The study of the systems was conducted over a one-year period starting in January 1998 and ended in January 1999. The evaluation of each system included monitoring the chemistry and using MINTEQA2, a chemical equilibrium computer program to assist in the analysis. Of all the major cations in solution, ferrous is the only one that is removed in the system.