Benefits of design-basis reconstitution in preparing 10CFR50.59 reviews

The paper discusses the situation at Omaha Public Power District's (OPPD's) Fort Calhoun station. One of the goals of the OPPD Design-Basis Reconstitution Project now in progress at the Ft. Calhoun nuclear station is to document the basis required to perform adequate 10CFR50.59 safety evaluations in an easily accessible and updated design-basis document (DBD). The DBD will reduced the research time and costs required to establish the design basis each time a safety evaluation is required. The end result is a completed DBD that resolves the difficulties described earlier. The DBD is a compilation, by text and reference, of the sources and documents that formulate the design basis for the plant. The design-basis reconstitution process also resolves conflicts between controlled documents such as drawings, specifications, Updated Safety Analysis Report, and licensing letters. System interactions and imposed requirements on the system or plant level issue are clearly identified in the DBD. Assumptions that were made in system and component design calculations are referenced and accessible along with the means for determining design and safety margins. Design-basis documents are updated on a regular basis rather than annually and therefore reflect the current design basis