Risk analyses for former ammunition depot Mitholz

In December 1947, part of the approximately 7000 tons of ammunition stored in the underground ammunition depot in Mitholz, Switzerland, exploded, killing nine people. Approximately 3500 tons of remaining ammunition containing several hundred tons of explosives are suspected in the collapsed facility and the rubble cone in front of the installation. Contrary to previous assumptions, a current risk analysis by the Swiss Department of Defence (DDPS) concludes that the risks of further possible explosions are significantly above the accepted limit values according to the Swiss Major Accident Ordinance. The Swiss Federal Office for the Environment (FOEN) as the responsible specialist agency has commissioned Fraunhofer EMI to evaluate the current risk analysis of the DDPS and its planned measures for risk mitigation. The second opinion by EMI has confirmed the assessment of the DDPS. Ongoing project work is dealing with complex questions about aging ammunition, the exact distribution of which is unknown under collapsed rock in the extensive area. Partial finds have shown that ammunition items are equipped with functioning fuses, the explosives are preserved in their original state, and explosive densities are present that make sympathetic detonation transmission possible.

More information on the pages of the DDPS.