Ahn, JS, Cheong, Y-W & Yim, G-J 2009, 'Water quality within mine waste impoundments at an incompletely remediated Cu-Pb-Zn mine site in Korea', in AB Fourie & M Tibbett (eds), Mine Closure 2009: Proceedings of the Fourth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 263-271, https://doi.org/10.36487/ACG_repo/908_19
(https://papers.acg.uwa.edu.au/p/908_19_Ahn/)
Abstract: Many of the closed mines in Korea have been abandoned without proper environmental protection measures. 
Some failures in preventing contamination from mine wastes have been reported even where remediation 
works were conducted. In this study, water quality variation in borehole groundwater and surface runoff was 
investigated on a seasonal basis within the waste impoundments at a mine site where previous rehabilitation 
measures were unsuccessful. The groundwater was typical acid mine drainage with pH 3.5–4.6 and high 
total dissolved solids (TDS) (390–3330 mg/L) during the dry season, and decreases of pH to 2.7–3.6 and 
increases in metal contents during the rainy season. Surface runoff showed a similar pattern of water quality 
variation. Good correlations were found between the concentrations of major and trace elements measured. 
It is suggested that dissolution of soluble secondary salts caused by flushing of weathered waste rocks and 
tailings directly influenced the water quality within the waste impoundments. Increases in acid and metal 
concentrations and their loadings from mine wastes are anticipated in the rainy season. It is necessary to 
apply more appropriate cover systems on waste rocks and tailings with the consideration of more extreme 
conditions in the study mine.