05000373/LER-2013-004
| Lasalle County Station, Unit 1 | |
| Event date: | 04-22-2013 |
|---|---|
| Report date: | 06-21-2013 |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| Initial Reporting | |
| 3732013004R00 - NRC Website | |
LaSalle County Station Units 1 is a General Electric Company Boiling Water Reactor with 3546 Megawatts Rated Core Thermal Power.
A. CONDITION PRIOR TO EVENT:
Unit(s): 1 Event Date: April 22, 2013 Event Time: 0723 CDT Reactor Mode(s): 2 Mode(s) Name: Startup Power Level: 0%
B. DESCRIPTION OF EVENT:
On April 22, 2013, Unit 1 was in Mode 2, Startup. At approximately 0723 hours0.00837 days <br />0.201 hours <br />0.0012 weeks <br />2.751015e-4 months <br /> CDT, reactor pressure was increased above 150 psig with the Reactor Core Isolation Cooling (RCIC)[BN] system isolated and inoperable.
Technical Specification (TS) LCO 3.5.3 requires RCIC to be operable in Mode 1, and in Modes 2 and 3 with reactor steam dome pressure greater than 150 psig. TS Required Actions (RA) A.1 and A.2 were entered and preparations were begun to warm RCIC and place it in service.
At approximately 0815 hours0.00943 days <br />0.226 hours <br />0.00135 weeks <br />3.101075e-4 months <br />, it was recognized that increasing reactor pressure greater than 150 psig with RCIC isolated and inoperable was a violation of TS LCO 3.0.4, which requires that entry into another Mode with an LCO not met shall only be made when the associated actions allow continued operation for an unlimited period of time. This was not the case for TS 3.5.3, and thus TS LCO 3.0.4 was not satisfied. Control rod withdrawals were stopped, and control rod insertion commenced in order to reduce reactor pressure and bring the Unit back into compliance with TS. At 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> RCIC was declared operable, and control rod insertion was stopped.
This event is reportable under 10 CFR 50.73(a)(2)(i)(B) as an event or condition prohibited by the plant's Technical Specifications.
C. CAUSE OF EVENT:
The cause of this event was a weakness in Normal Unit Startup procedure LGP-1-1 in that there was no specific procedure step to verify RCIC operability prior to exceeding 150 psig. LGP-1-1 does contain a limitation stating that RCIC operability is required prior to exceeding 150 psig but this would have been more effective if it had been a specific procedural step. In addition, there was a lack of recognition of the impact of TS LCO 3.0.4 by Operations with respect to RCIC operability.
D. SAFETY ANALYSIS:
The safety significance of this event was minimal. High Pressure Core Spray (HPCS)[HG] was verified operable when reactor pressure exceeded 150 psig at 0723 hours0.00837 days <br />0.201 hours <br />0.0012 weeks <br />2.751015e-4 months <br /> in accordance with TS 3.5.3 RA A.1. RCIC was inoperable with reactor pressure in excess of 150 psig for approximately 97 minutes, which is significantly less than the TS 3.5.3 RA A.2 Completion Time of 14 days.
E. CORRECTIVE ACTIONS:
- LGP-1-1 was revised to add sign offs to verify TS compliance prior to changing Modes or entering specified Conditions.
- This event will be reviewed with all licensed operators to reinforce the requirements of TS LCO 3.0.4 when changing Modes or entering specified conditions.
F. PREVIOUS OCCURRENCES:
A review found no previous occurrences in the past ten years of violating TS 3.0.4 by exceeding 150 psig reactor pressure with RCIC inoperable.
G. COMPONENT FAILURE DATA:
There were no component failures associated with this event.
LaSalle County Station, Unit 1 05000373