ABSTRACT
The use of open standpipe piezometers, in monitoring of the piezometric levels in tailings dams, is common practice in South Africa. These piezometers are often installed as single piezometers, in a line, to monitor the piezometric level at various cross sections through the tailings dam. Case studies in South Africa have indicated that the true phreatic surface is not always well presented by single open standpipe piezometers. Furthermore open standpipes suffer from a time lag in detecting fluctuations in the piezometric level. This paper discusses the shortcomings of monitoring of the phreatic surface in tailings dams with single standpipe piezometers and concludes with a case study of incorrect ‘phreatic levels’ at platinum tailings dams in South Africa. It is recommended that multiple piezometers be installed at critical sections.
