CASTOR AND TERROR

A recently published German report by Dr. Helmut Hirsch and Wolfgang Neumann discusses the safety of CASTOR transport and storage casks in case of terrorist attacks. The report Verwundbarkeit von CASTOR-Behälter bei Transport und Lagerung gegenüber terroristischen und kriegerischen Einwerkungen sowie zivilisatorischen Katastrophen (Vulnerability of CASTOR casks in transport and storage to terrorist and military impacts as well as conventional catastrophes; November 2001) mainly focuses on two scenarios: the attack with an armor-piercing weapon and the crash of a commercial aircraft on a storage building.

If a cask were shot at with a modern armor-piercing weapon during transport, the cask wall would be penetrated. The report mentions five modern weapons that can penetrate armor plate 400 to more than 1000 mm, whereas CASTORs have only 440mm walls of cast steel, which is weaker. A percentage of 0.5% of the highly radioactive spent fuel or vitrified waste would be pulverized after the impact along the path of the projectile. In case of vitrified waste, 900 Tera Becquerel of cesium-137 would be released and with spent fuel 430 Tera Becquerel (1 Tera Becquerel is 10¹² Becquerel). The release would lead to a radioactive contaminated zone around the place of attack. The contamination would be so severe that entering this zone would be virtually impossible. A cloud of radioactive aerosols would be released, possibly necessitating countermeasures at distances as far as several kilometers.

If a large commercial aircraft crashes on an intermediate storage facility, a fire lasting several hours could result. Large aircraft can contain some tens of thousands liters of kerosene fuel and temperatures in such fires can reach 1000^oC for several hours. A CASTOR cask is designed to withstand a fire of 800^oC for only 30 minutes. The crash of an airplane on a storage hall would result in the failure of a considerable number of casks. An amount of more than 1000 Tera Becquerel of cesium-137 would leak from the casks and become airborne. Due to the fire, the radioactive substances could spread over a large area. Thousands of square kilometers of land would become contaminated to a degree that renders agricultural use impossible.

A special section in the report deals with the problems arising from the public availability and discussions of sensitive information. The fact that all the technical data used in the report can be accessed by terrorists does not imply that a more restrictive policy towards information is required. According to the authors, "Rather, it should be regarded as an argument against the use of a technology which is, at the same time, hazardous and complex to a large degree, creating a conflict between the necessary societal discussion on the one hand and the protection of society from terrorist attacks on the other."—WISE Amsterdam

The report (in German) can be downloaded from: