The inspectors identified a Green
NCV of Unit 2
Technical Specification (TS) 5.4, Procedures, for Exelons failure to properly perform procedure N2-OSP-GTS-R001,
Secondary Containment Integrity Test, Revision 01100. Specifically, Exelon staff failed to ensure spectacle
flanges associated with alternate decay heat (ADH)
secondary containment isolation were properly installed. As a result, surveillance testing associated with ADH
check valves 2ADH*V21A/B and 2ADH*V22A/B was not performed to ensure
secondary containment integrity as required by N2-OSP-GTS-R001. Exelon immediately entered this issue into their
CAP as
issue report (IR) 2403311. Exelon entered TS
Surveillance Requirement (SR) 3.0.3, Limiting Condition for Operability Applicability, which is used when a licensee discovers that a surveillance test requirement has not been performed. As required by the TS, Exelon completed a risk evaluation of the
missed surveillance and determined
large early release frequency remained low without ADH
secondary containment isolation. Exelon also performed extent-of-condition inspections for other systems which may not have proper alignment to ensure they are meeting TS requirements. On December 4, Exelon rotated the spectacle
flanges to the no flow isolation position to ensure
secondary containment integrity was maintained
The finding is more than minor because it is associated with the configuration control attribute of the Barrier Integrity cornerstone objective to provide reasonable assurance tha
physical design barriers protect the public from radionuclide releases caused by accident
or events. Specifically, by performing N2-OSP-GTS-R001 in 2012 and 2014 without first ensuring the spectacle flanges were properly installed, Exelon did not verify the secondar
containment requirements of TS SR 3.4.6.1 were maintained. Additionally, this issue wa
similar to Example 3.d in IMC 0612, Appendix E, Examples of Minor Issues, in that th
failure to implement the TS SR as required was not minor if the surveillance had not bee
conducted. By not correctly testing the secondary containment in 2012 and 2014, the SR o
TS 3.4.6.1 was not met. In accordance with IMC 0609.04, Initial Characterization o
Findings, and Exhibit 3 of IMC 0609, Appendix A, The Significance Determination Proces
for Findings At-Power, the inspectors determined this finding is of very low safet
significance (Green) because the finding only represents a degradation of the radiologica
barrier function provided for the control room, or auxiliary, spent fuel pool (SFP), or standb
gas treatment system (boiling water reactor). This finding has a cross-cutting aspect in th
area of Human Performance, Avoid Complacency, because Exelon staff did not implemen
appropriate error reduction tools. Specifically, operators did not use error reduction tools t
ensure the spectacle flanges were installed in the no flow position and as a result, the
failed to leak test the ADH check valves in the secondary containment drawdown test a
required by N2-OSP-GTS-R001 [H.12].
