Upon review of industry operating experience regarding unfused remote direct current ammeter circuits, the licensee discovered a similar configuration existed at Palisades. The wires supplying a current signal from the output of each station battery to their respective ammeters in the adjacent room were unfused. As a result, a fire in either battery room could create multiple grounds which could cause the wire to heat up and cause a secondary fire in the adjacent space (Cable Spreading Room). This condition represented a degraded
fire barrier and was contrary to the requirements in
10 CFR 50, Appendix R, Fire Protection Program for Nuclear Power Facilities Operating Prior to January 1, 1979, specifically,
Section III G.1. Because the licensee committed to adopt National Fire Protection Association (
NFPA) 805 and revise their fire protection licensing bases to comply with
10 CFR 50.48(c), and this commitment was documented prior to December 31, 2005, the NRC is exercising enforcement and
ROP discretion for this issue in accordance with the
NRC Enforcement Policy, Section 9.1,
Enforcement Discretion for Certain Fire Protection Issues (
10 CFR 50.48) and
IMC 0305. This issue was identified and addressed during the licensees transition to
NFPA 805, it was entered into the licensees
CAP as
CR-PLP-2013-04817, immediate corrective action and compensatory measures were taken, it was not likely to have been previously identified by routine licensee efforts, it was not willful, and it was not associated with a finding of high safety significance (Red). Specifically, utilizing
IMC 0609 Appendix F, Attachment 1, Fire Protection
SDP Phase 1 Worksheet, the issue screened as having very low safety significance per Question 1.4.3.C based on the presence of an automatic fire suppression system.
