05000341/LER-2012-004
| Docket Number Sequential Revmonth Day Year Year Month Day Yearnumber Nd. 05000 | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3412012004R00 - NRC Website | |
Initial Plant Conditions:
Mode�1 Reactor Power�68 percent
Description of the Event
During an engineering review of Environmental Qualification & Surveillance, it was discovered that the cable connector assemblies associated with the Primary Containment Isolation Valve (PCIV) position indication limit switches for the inboard Reactor Water Sample System valve, B3100-F019, had exceeded their Environmentally Qualified (EQ) life.
On August 27, 2012 at 11:45 hours the inboard PCIV position indication was declared inoperable.
Position indication of the B3100-F019 is required by TS 3.3.3.1, "Post Accident Monitoring (PAM) Instrumentation," in order to verify primary containment integrity during accident situations. TS 3.3.3.1 requires two channels of PCIV position indication per primary containment penetration. This inoperability resulted in entering Condition A of TS 3.3.3.1 for one PCIV position indication out of two required channels per penetration flow path inoperable, which requires restoration of the inoperable PAM instrumentation channel to operable status within 30 days; otherwise, Condition B is entered.
Action B requires a PAM Report be submitted in accordance with TS 5.6.7 within 14 days. A PAM Report has been issued to outline the action taken, the cause of the inoperability, and the plans and schedule for restoring the instrumentation channel.
After the condition was identified and evaluated, EQ subject matter experts could not assure the limit switch cable connector assemblies could have endured the design basis accident, had it occurred prior to discovery. It was determined that this condition existed for greater than the allowed completion time for TS 3.3.3.1 and was therefore an operation or condition prohibited by the TS.
Significant Safety Consequences and Implications This event posed no significant risk to the health and safety of the public because position indication for B3100-F020, the outboard PCIV for this penetration, remains operable and continues to provide Environmentally Qualified (EQ) position indication and isolation capability. Additionally, both the B3100-F019 and B3100-F020 are 3/4 inch normally closed valves receiving accident related isolation signals on low reactor water level, high drywell pressure and high main steam line radiation.
This event is being reported under 10 CFR 50.73(a)(2)(i)(B), any operation or condition prohibited by TS.
Cause of the Event
The requirements of an EQ Maintenance and Surveillance (M&S) program were not correctly incorporated into the technical requirements of a Preventive Maintenance (PM) Event in 1994. The PM Event basis did not address the entire boundary of the limit switch EQ in the scope of the PM event.
The direct cause of the event was a failure to provide the necessary requirements for maintaining the EQ life for the cable connector assemblies limit switches for valve B3100-F019 in a PM event. The apparent cause was a failure to require a subject matter expert review for translating EQ requirements into the PM requirements.
Corrective Actions
This event has been entered into the Fermi 2 Corrective Action Program. The cable connector assemblies will be replaced during Refueling Outage 16 when plant conditions allow access to the primary containment, currently scheduled for the first quarter of 2014. Procedures are to be revised to include requiring a Subject Matter Expert (EQ Engineer) PM Technical Requirements and Frequency review.
A review of the full scope of the current EQ for this type of cable connector assemblies on limit switches was performed. The condition is limited to the cable connector assemblies for valve B3100- F019.
Additional corrective actions may be identified as a result of this effort.
Additional Information
A. Failed Component: None
B. Previous Similar Events:
There are no similar previous events within the past five years.