Safeguards Approach for Gas Centrifuge Type Enrichment Plants

For many years, safeguards experts have wrestled with the problem of how to get effective and credible safeguards at uranium enrichment plants while protecting sensitive information and minimizing the operator's burden. In an effort dedicated to solving this problem for gas centrifuge uranium enrichment plants subject to INFCIRC/153-type safeguards agreements, six technology holders and the inspectorates of the IAEA and Euratom created the Hexapartite Safeguards Project (HSP) in November 1980. After 2 1/2 years of intensive study it was concluded that, for commercial gas centrifuge uranium enrichment plants in NPT states, the safeguards approach involving limited-frequency unannounced access (LFUA) by IAEA inspectors to cascade areas offers the best solution. This report, based on the text produced by the HSP, provides (1) the essential details of the project, (2) the "LFUA" safeguards approach, and (3) the possible inspection activities inside and outside the cascade areas.