05000335/LER-2001-008
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3352001008R00 - NRC Website | |
FACILITY NAME (1) UCCAkf LER NUMBER (6)
Description of the Event
On June 11, 2001, St. Lucie Unit 1 was in Mode 1 at 100 percent reactor power. The AN channel reactor vessel level monitoring system (RVLMS) was out of service (OOS), and the 30 day special report required by TS 3.3.8 Action 4 was submitted by FPL by letter L-2001-128 on May 31, 2001. The 1B emergency diesel generator (EDG) also had a degraded radiator on the 12-cylinder engine. As part of the operability assessment-directed compensatory measures, the monthly Technical Specification (TS) EDG surveillance was being performed on a bi-weekly frequency. During the performance of the 1B EDG augmented surveillance run on June 11, 2001, the 12 cylinder 1B2 EDG developed a radiator leak. The 1B EDG was declared OOS pending replacement of the EDG radiator cores. Replacement cores were not available on site and were procured in an expedited manner. On June 15, replacement cores for the 1B2 EDG radiator were received on site, the cores were replaced, and the 1B EDG was returned to service on June 17, 2001. Although the opposite train RVLMS was 008 concurrent with the 1B EDG, St. Lucie Unit 1 did not enter TS 3.8.1.1 Action b because FPL did not consider RVLMS to be a required critical safety-related system.
This TS position was documented in St. Lucie Condition Report 01-1237.
On October 9, 2001, FPL was informed via telephone that the NRC Staff did not agree with the documented St. Lucie TS position regarding opposite train verification requirements with an inoperable EDG. The LER "discovery" clock for the June event was started at this time.
Cause of the Event
The cause of this event was that the literal wording of the subject TS did not support FPL's interpretation that "required" implied a critical safety-related system whose loss would result in the system's TS requiring a shutdown. FPL submitted a TS change to align the St. Lucie TS with the Combustion Engineering (CE) Standard Technical Specification (STS) wording. The CE STS wording clearly allows continued operation with an inoperable EDG (subject to the EDG allowed outage time) and inoperable opposite train features that do not provide critical safety functions.
Analysis of the Event
This condition is reportable under 10 CFR 50.73(a)(2)(i)(B) as operation prohibited by the facilities' TS.
Analysis of Safety Significance TS 3.8.1.1 Action b states in part that:
"With one diesel generator of 3.8.1.1.b inoperable- verify within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> that:
1. all required systems, subsystems, trains, components and devices that depend on the remaining OPERABLE diesel generator as a source of emergency power are also OPERABLE- A literal interpretation of the subject TS did not support FPL's interpretation. The CE STS wording clearly allows continued operation with concurrent EDG (subject to the EDG allowed outage time) and opposite train feature inoperability, as long as the inoperable feature does not provide a critical safety function. FPL submitted a proposed TS amendment to implement the CE STS wording for opposite train feature requirements with an inoperable EDG. Because the TS amendment will allow operation comparable to FPL's former interpretation of the current TS, this event had no impact on the health and safety of the public.
Corrective Actions
1. FPL submitted proposed St. Lucie TS amendments on October 17, 2001 via FPL letter L-2001-230.
Additional Information
Failed Components Identified None Similar Events None FACILITY NAME (1) I NUMBER (R_ St. Lucie Unit 1 05000335 NRC FORM-USA (1.2001