Tailings storage facilities (TSFs) will, after closure of the mine, have to be stable in a long-term perspective (e.g. 1,000 years or more). In many cases, due to the characteristics of the tailings, a high phreatic surface is required to keep the tailings saturated in order to prevent, or minimise, the process of oxidation. Due to this the slope stability of the embankment, or the land form slope, is critical as any material exposed to a hydraulic gradient is exposed to a load. So, the question is: Is the embankment, or landfill slope, that is exposed to a hydraulic gradient safe in the long term with respect to the actual design and material properties? In order to answer that question, an understanding of the structure, its stability and level of actual safety during operation is necessary. This paper will therefore discuss slope stability for embankments during operation and the long-term perspective and how the factor of safety (FS) can be verified. Practice today for dam stability is that a certain FS is required, i.e. a safety margin (in Sweden FS>1.5), and for that condition we design the embankment. The design includes the geometry of the structure, material properties, water management/water levels and requirements for compatibility between different materials, as well as for construction and operation. The FS can, however, not be physically measured on, or in, the actual embankment. What can be measured is seepage, pore pressure and movement (vertical and horizontal displacements). But how can the readings be used to verify the actual FS? In order to illustrate this, an example from a TSF in northern Sweden is presented where readings have been taken through numerical modelling (PLAXIS), comprehensive geotechnical investigations, lab testing and inclinometers. In order to predict how an embankment, or landform slope, will behave in the long-term phase and what the actual FS will be, the authors believe it is necessary to understand the behaviour of the structure during operation. The method used for the example illustrated in this paper shows a method to gain an understanding for a structure, which is absolutely crucial for understanding the actual FS and for the possibility to predict the level of safety in the long term.

The International Commission on Large Dams (ICOLD) is a non-governmental international organisation that was established in 1928 as a forum for the exchange of knowledge and experience in dam engineering. This organisation is made up of various subcommittees, one of which is the Committee on Tailings Dams and Waste Lagoons. Formed in 1928, this subcommittee has produced a number of bulletins related to tailings dam design. The next bulletin, "Sustainable Design and Post-Closure Performance of Tailings Dams", will be published in 2011/12 for tailings dam designers intending to achieve sustainable development. Sustainable development in this paper is defined according to the Bruntland Report (UNWCED, 1987): "development that meets the needs of the present without compromising the ability of future generations to meet their own needs". This means that mining projects, including tailings management facilities (TMFs), should be financially viable, technically appropriate, environmentally sound and socially responsible (ICMM, 2008). In order to fulfil that brief, closure of TMFs need to be managed carefully. This new ICOLD Bulletin is intended to be a guide in this process. The Bulletin is compiled into three major sections, with in-depth discussion on the following:  Sustainable closure principles, covering closure objectives, closure design life, the influence of deposition methods, financial principles, regulations and risk management principles.  Sustainable design considerations, covering consequence classification at closure, long term physical stability, ecological and social stability.  Long-term monitoring: covering instrumentation and control after remediation has taken place. This paper sets out some of the guiding principles and details that will be contained in the new ICOLD bulletin.

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Fäboliden is a planned new Swedish goldmine, owned by Lappland Goldminers AB. A permit granting commencement of operations was issued in December 2007, but was subsequently appealed by the Swedish

Mining operations have a big environmental impact wherever they are located. Unsuccessful operation and/ or inadequate planning for closure has in several cases increased the impact, causing costly environmental liabilities without finance. The consequence is, generalized, difficulties to get permits, in some countries more or less impossible. Metals and minerals are, however, necessary for our society and even more so with the "green transformation", i.e. the change from fossil fuels to sustainable sources of energy (windmills, solar power, electrical cars etc. etc.).Mining has developed over centuries. With time, extraction processes have been refined resulting in a (still) increasing amount of waste materials, such as waste rock and tailings. The mining industry is the industry, globally, moving the largest volumes of materials. These materials are generalized a problem, a waste.Traditionally, mining operations are run by engineers using logic, "straight lines", effective processes in order to produce good quality products. The waste materials produced have been, and still are, seen as a waste product, i.e. a problem to be solved as efficiently as possible at the lowest cost. Sometimes at a too low cost, which in the worst case may result in incidents or failures of tailings management facilities or inappropriate closure, none of them acceptable. This paper will discuss, from the authors point of view, possible ways of how mining operations may change into a positive element within our society. This require a new mindset and a different strategy within the industry. The authors believe this change could be to "use" mining, i.e. the materials produced, to create a value. By this many things can probably be achieved like; improved reputation, society/ community engagement, long term commitment and safer long-term solutions. The authors believe that these are key ingredients to obtain acceptance for the industry and more constructive permitting processes.