Diablo Canyon Facility Operating License
DPR 80/DPR 82, License Condition 2.C(5), Fire Protection, required Pacific Gas and Electric to implement and maintain all provisions of the approved fire protection plan as described by the FSARU. FSARU, Appendix 9.5a, Fire Hazards Analysis, and Equipment Control Guideline 18.7, Fire Rated Assemblies, required that all fire
penetration seals necessary to protect
safe shutdown equipment be
operable. Contrary to the above, on January 13, 2011, the licensee identified that the
penetration seal for Conduit K2026, providing a 4-kV power cable between Fire Area 20, Unit 2 12-kV Cable Spreading Room, and Fire Area 19A, Unit 2 Turbine Building, was missing the internal seal. The licensee subsequently identified that several additional
penetrations were not installed per the design specification. In both Unit 1 and Unit 2 12-kV cable spreading rooms, several conduits were installed with nonconforming materials that did not meet the 3-hour
fire barrier rating. The licensee implemented appropriate compensatory measures following discovery of the condition and entered the problem into the corrective action program as Notifications 50370048, 50371018, 50371019, 50370858 and 50370859. The inspectors determined that the finding was of very low safety significance (Green) because the degraded barriers would provide a minimum of 20 minutes fire endurance protection and in situ fire ignition sources and combustible or flammable materials were positioned such that the degraded barrier would not be subject to direct flame impingement.
