Post-Mining 2005, November 16-17, Nancy, France 1 MANAGING THE MINING SUBSIDENCE HAZARD IN LORRAINE DISSART Yannick 1 , VERDEL Thierry 2 1 Groupe de Recherche en Economie Financière et Gestion des Entreprises, Pôle lorrain de gestion - 13 rue Michel Ney – CO 75 – 54037 Nancy Cedex, - France.; yannick.dissart@mines.inpl-nancy.fr 2 Laboratoire Environnement, Géomécanique et Ouvrages, INPL – Ecoles des Mines de Nancy - Parc de Saurupt – CS 14234 - 54042 Nancy Cedex - France. thierry.verdel@mines.inpl-nancy.fr ABSTRACT: The concept of governance makes it possible to involve three stakeholders in the management of post-mining subsidence hazards in Lorraine (East of France): the State, mining companies and the civil society. On the basis of this partition, it is possible to describe each one of them in order to study the various players through a community of logic. The study of the relationships between players shows the complexity of post mining treatment. Using an approach that takes into account not only the present but also the past makes it possible to give starts of answers regarding the non anticipation of this problem and the difficult issue it has become. KEYWORDS: decision, governance, risk of mining subsidence, stakeholders. RESUME : La notion de gouvernance permet de situer trois parties prenantes dans la problématique des affaissements miniers en Lorraine : l’Etat, les exploitants miniers et la société civile. Partant de cette partition, il est possible de décrire chacune d’entre elles afin d’aborder les différents acteurs à travers une communauté de logique. L’étude des relations entre acteurs montre la complexité dans le traitement de l’après mines. C’est au travers d’une approche qui prend en compte non seulement le présent mais également le passé qu’il est possible de donner des pistes de réponses quant à la non anticipation de ce problème et au dossier délicat qu’il est devenu. MOTS-CLEFS : décision, gouvernance, risques d’affaissements miniers, acteurs. 1. Introduction The year 1996 remains engraved in the memory of the Lorraine population. Two subsidence events occurred within a limited time, starting a large social movement. Subsidence events are not rare. Some have been reported in Paris starting in 1776. In 1783, a mining control office is created under Louis XVI. In 1810, the mining code creates an administrative monitoring of mining exploitations in order to avoid the wasting of ore-fields and to ensure public safety and workers protection. The subsidence events induced by mining activities are thus known and regulated for over two centuries in France. Piguet (1999), DRIRE (2003) and Forbes (2004) gave information about the first after-effects of mining subsidence in Lorraine. The first sudden collapse would have occurred in 1902 in Audun Le-Tiche, the first subsidence following the removal of mining pillars happened in Moutiers in 1954, the first subsidence due to the rupture of abandoned rooms and pillars excavations happened in Jarny between 1932 and the first reported sinkhole occurred in Thil in 1957. Lorraine Iron Desposit has been exploited for more than two centuries. In the 1970s, the mining extraction intensity started to decrease but post-mining problems only started to emerge in the 1990s.