LANL is dedicating substantial and effective internal resources to support this design upgrade. LANL had the concrete strength and reinforcing steel placement surveyed to verify the construction quality of the original facility without complete construction records.
Results indicate that the concrete strength meets construction specifications in the areas surveyed.
LANL representatives are aware of these issues and are developing a plan for resolution. Thermal analyses for the proposed vault passive cooling system indicate that the design margin in meeting temperature limits is not large. As a result, the final design of the holding fixture for the SNM container will need to be sufficiently robust to satisfy maximum SNM temperature limits. Relatedly, consideration should be given to monitoring air and drywell temperatures and vault air effluents. The preliminary design of the existing NMSF commenced in 1984, and construction was completed in 1987 under supervision of the U.S. Army Corps of Engineers.