At 8 a.m., an uncontrolled release of ethane occurred ; the leak developed in a horizontal pipe linking the two wellheads of cavern 103, an ethane storage cavity equipped with a product well and a brine well. The ethane caught fire at 9:40 a.m. Fire-control experts sprayed water to cool down the two well-heads. Cavern pressure dropped as the cavity slowly emptied. On September 1, the small remaining fire on the brine well was outfitted with a new master valve. On September 4, a plug was set down hole in the second well, and the emergency was declared over. The large ethane volume that filled the underground salt cavern (76 000 m3 – half full) made the situation difficult to handle. Crisis management was effective and included an information centre, a 24-hour emergency line, daily media briefings and individualized meetings with the residents. Updated information was made available on a web site.