Seismic equipment qualification at Rocky Flats Plant: Lessons learned

Seismic equipment qualification is being evaluated as a part of the Systematic Evaluation Program (SEP) at the Rocky Flats Plant (RFP). The experience database developed by the Seismic Qualification Utility Group (SQUG) as outlined in their Generic Implementation Procedure (GIP) was initially studied for the qualification of equipment at RFP. However, detailed review of the simplified guidelines contained in the GIP revealed substantial differences between components and structures at RFP and those at commercial nuclear power plants. The RFP structures are significantly less massive, and more flexible than the large reinforced concrete shear wall and steel moment resisting frame structures typically found at commercial nuclear power plants. Much greater amplifications of ground motion result from the response of the RFP structures that substantially limit the applicability of the simplified Bounding Spectrum evaluation approach contained in the GIP. Therefore, more rigorous evaluations are required for substantially greater numbers of components that are included in the GIP equipment classes. In addition, there are a substantial number of component classes at RFP that are not present in typical nuclear power plants (e.g., glove boxes, welded tubular HVAC ducts, and process piping) that are not included in the GIP. This paper presents the details of the differences between the RFP structures and components and those represented in the GIP, the challenges that were presented for their evaluation at RFP, and EG ampersand G's approaches to develop seismic qualification data