In 2005, Prof. Nielen Van der Merwe, at that time President of the ISRM, initiated a commission to facilitate the constitution of an international network of experts involved in mine closure and post-mining management. Eight experts coming from different countries have been deeply involved in this ISRM "mine closure commission", for four years.
Closure of mining operations does not lead to the complete elimination of risks likely to affect the surface above old mine workings. Therefore, disorders potentially harmful for people and goods may develop, sometimes just after the closure but also, in some cases, long time after.
The first mandate of the commission has been dedicated to the elaboration of a state-of-the- art report presenting, at an international scale, the mine closure problem (context, main risks of disorders, major hazard assessment methods and treatment techniques). The present paper presents an outline of this ISRM report that members may download on the ISRM website.
The mine closure Commission has been appointed with two main objectives. The first one was to facilitate contacts between experts in rock mechanics from different countries concerned with post mining management in order to create opportunities to exchange experiences, case studies and scientific data.
The second objective of the commission was to elaborate a reference document, presenting the international "state-of-the-art" for existing techniques and methods enabling identification, characterisation and management of geotechnical hazards related to mine closure processes (Didier et al., 2008).
An expert panel has thus been constituted to elaborate the document. All the members that joined the commission got involved on a strictly voluntary basis and gave considerably of their time and their expertise to the benefit of the commission work. They are listed below:
Christophe DIDIER, INERIS, Verneuil-en-Halatte, France. President of the Commission.
Nielen Van der MERWE, Bon-Terra Mining Ltd, South-Africa. Past President of the ISRM.
Ömer AYDAN, Tokaï University, Shizuoka, Japan.
Marc BÉTOURNAY, CANMET, Mining and Mineral Sciences Laboratories, Ottawa, Canada.
Jean-Pierre JOSIEN, GEODERIS, Metz, France.
Andrej KOTYRBA, Central Mining Institute, Katowice, Poland.
Mark MAINZ, IHS (Ingenieurbuero Heitfeld- Schetelig), Aachen, Germany.
Won-Kyong SONG, Korea Instit. of Geoscience and Min. Resources, Daejeon, Korea.
The mine closure state-of-the-art report contains 7 sections and 3 appendices. After a brief presentation of the mine closure context, at an international scale, the document describes precisely the most frequent geomechanical hazards that may develop above an abandoned mine. In addition to the description of consequences and potential effects on people and surface structures, the basic mechanisms that may initiate the failure are discussed.
The commonly used hazard assessment methods are then described, with a particular attention to the key factors that have to be taken into account in the assessment process. Classical post-mining risk management methods are then discussed: voids treatment, monitoring methods, land use management. Specific references are included at the end of each section and recommended additional literature is also given.
