By Steven H. Emerman, Ph.D.
The probability of failure by static liquefaction of the tailings dams at the Riotinto Mine is very high. The sequence of events thus far is very similar to the sequence of events that led to the failure of the tailings dam at the Samarco Mine in Brazil, including the use of upstream construction. Excavations at the edge of the dam show that the water table within the tailings is only 1-2 meters below the surface. Furthermore, uncontrolled seepage near the top of the dam indicates that nearly the entire dam and tailings are saturated with water. My recommendations were that addition of water and tailings to the dam must cease and that plans for draining the tailings must be developed immediately. In fact, the Supreme Court of Andalucía annulled the environmental license for the mine on June 27. I am writing a full report on these tailings dams, which will be released by London Mining Network.
The proposal for the tailings dams at the Touro Mine disregards the most basic concepts of dam safety. The proposed 81-meter-high dam would be placed on a steep slope 200 meters above the village of Arinteiro and 1000 meters above the village of Loxo. By contrast, according to the new Brazilian legislation, it is illegal to build or increase the height of a tailings dam when there is a population residing within 10 kilometers downslope of the dam (referred to as the “self-rescue zone”). Even so, any dam for which the failure would result in the loss of human life should be designed to resist the Probable Maximum Flood and the Maximum Credible Earthquake. These concepts have not been considered anywhere in any of the plans for the tailings dams. My report on the proposed Touro Mine was Tramadol Online Yahoo Answers.
The tailings dams for the abandoned San Finx Mine were constructed in the 1920s and 1930s and are in serious need of repair. The plans for re-opening the mine deny that these are tailings dams and even deny the need for tailings dams, based upon a claim that the natural background levels of contamination are far higher than the contamination limits set by Spanish law. This claim is based upon incorrect procedures and miscalculations. My report on the existence of natural background contamination will be released shortly by ContraMINAcción.
I would be very happy to assist other organizations with concerns about existing or proposed mining projects. I can be contacted at SHEmerman@gmail.com
Watch an interview with Prof. Steven Emerman during his stay at Santiago de Compostela by journalist Pilar Aymara