SREL Reprint #2430

Treatment of acid mine drainage using anaerobic constructed treatment wetlands: predicting longevity with substrate neutralization potential

Robert C. Thomas1,2, Christopher S. Romanek1,2, Daniel P. Coughlin2, and Douglas E. Crowe1

1Department of Geology, University of Georgia, 210 Field Street, Athens, GA, 30602 USA
2Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802 USA

Abstract: Anaerobic constructed treatment wetlands (CTW) have been shown to be an effective means of neutralizing acid mine drainage. The integrity of anaerobic CTWs is inherently rooted in the health of resident anaerobic microbial communities and it is the contaminant load delivered to the CTW that dictates the dominant community. Sizing recommendations have been developed based on contaminant loading from both a biotic and abiotic perspective; however these have failed to allow prediction of the CTW longevity. Since ultimately it is the buffering capacity of the substrate that sustains the healthy anaerobic microbial community, the total neutralization potential of a given volume of organic substrate may be used to predict the longevity of an anaerobic CTW. This method of prediction was tested in a column study and the results are evaluated in this presentation. Neutralization potential as a predictive tool is thought to be ineffective at high loading rates and low residence time where preferential flow may develop and at low loading rates and high residence time as the biologic oxidation of organic matter becomes increasingly significant. Over estimates may be made in the case of the former and under estimates in the case of the latter.

Keywords: Anaerobic wetland, Neutralization Potential, Predicting Longevity

SREL Reprint #2430

Thomas, R. C., C. S. Romanek, D. P. Coughlin, and D. E. Crowe. 2000. Treatment of acid mine drainage using anaerobic constructed treatment wetlands: predicting longevity with substrate neutralization potential. pp. 449-458 In: D. Goldsack, N. Belzile, P. Yearwood, and G. Hall (Eds.). Mining and the Environment II. Laurentian University, Sudbury, Ontario, Canada.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).