NUCLEAR CRITICALITY SAFETY CONSIDERATIONS FOR CASTOR CASKS WITH SPENTFUEL OF THE ROSSENDORF NUCLEAR DEVICES

The spent fuel of the shut down Rossendorf nuclear devices is to be lo aded into storage and transport casks of the type CASTOR-MTR-2. Accord ing to the variety of different nuclear devices at the Rossendorf site , the Rossendorf fuel is characterized by a great variety with regard to geometry, material, enrichment, and burn-up. According to the speci al loading conception, the fuel is embedded in aluminium bodies that f ill the CASTOR. The void fraction within the CASTOR is very small resu lting in a small water fraction if water flooding is assumed. The crit icality safety is proved by MCNP and OMEGA calculations. These are ind ependent codes that use a completely different data base. The results of both codes agree very well demonstrating the reliability of the cal culations. Apart from the proof of criticality safety, some interestin g features were found mainly as a result of the very small water fract ion. (C) 1997 Elsevier Science S.A.