05000424/LER-2012-003, Regarding Failure to Comply with Technical Specifications LCOs 3.7.14 and 3.0.3
| ML122910935 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/16/2012 |
| From: | Tynan T Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-12-2089 LER 12-003-00 | |
| Download: ML122910935 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2) |
| 4242012003R00 - NRC Website | |
text
Tom Tynan Southern Nuclear Vco Prt',dlmt V09tl, Operating Company. Inc.
7)11 ANp.r Road Wayn SIJOIO, Georg a 0830 Tel 106 82G 315' f'l~ IQ., HZ6 3::11 SOUTHERNA October 16, 2012 COMPANY Docket No.:
50-424 NL-12-2089 U. S. Nuclear Regulatory Commission ATIN: Document Control Desk Washington, D. C. 20555-0001 Vogtle Electric Generating Plant-Unit 1 Licensee Event Report 2012-003-00 Failure to Comply with Technical Specification LCOs 3.7.14 and 3.0.3 Ladies and Gentlemen:
In accordance with the requirements of 10 CFR 50.73 (a)(2)(i)(B), Southern Nuclear Operating Company (SNC) is submitting the enclosed Licensee Event Report. This letter contains no NRC commitments. If you have any questions, please contact Doug McKinney at (205) 992-5982.
Respectfully submitted, T. E. Tynan Vice President - Vogtle TET/GWG Enclosure: Unit 1 Licensee Event Report 2012-003-00 cc:
Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Mr. B. L. Ivey, Vice President - Regulatory Affairs Mr. B. J. Adams, Vice President - Fleet Operations Mr. M. J. Ajluni, Nuclear Licensing Director RType: CVC7000 U. S. Nuclear Regulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager - Vogtle Mr. L. M. Cain, Senior Resident Inspector - Vogtle
Vogtle Electric Generating Plant - Unit 1 Licensee Event Report 2012-003-00 Failure to Comply with Technical Specification LCOs 3.7.14 and 3.0.3 Enclosure Unit 1 Licensee Event Report 2012-003-00
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 10/3112013 (10-2010)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection
- 1. FACILITY NAME
- 3. PAGE VogUe Generating Plant - Unit 1 1 OF 4
- 4. TITLE Failure Comply with Technical Specification LCOs
- 5. EVENT DATE
- 6. LER NUMBER ER FACILITIES INVOLVED DOCKET NUMBER SEQUENTIAL REV MONTH DAY MONTH DAY YEAR YEAR NUMBER NO.
FACIUlY NAME i DOCKET NUMBER 08 19 2012 2012 - 003 - 00 10 17 2012
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)
- 9. OPERATING MODE o 20.2201 (b) 0 20.2203(a)(3)(i) 0 50.73(a)(2)(i)(C)
D 50.73(a)(2)(vii) o 20.2201 (d)
D 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A) 1 o 20.2203(a)(1)
D 20.2203(a)(4) 0 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) o 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 0 50.73(a){2)(iii) o 50.73(a)(2)(ix)(A) 1---------1 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(iv)(A) o 50.73(a)(2)(x)
- 10. POWER LEVEL 20.2203(a)(2)(iii)
D 50.36(c)(2) 0 50,73(a)(2)(v)(A)
D 73.71(a)(4) 20,2203(a)(2)(iv)
D 50,46(a)(3){ii) 50.73(a)(2)(v)(B)
D 73.71{a)(5) o 20.2203(a)(2)(v)
D 50 73(a)(2)(i)(A)
[] 50.73(a)(2)(v)(C)
OTHER 100 D 20.2203(a)(2)(vi)
~ 50.73(a)(2)(I)(B)
[J 50.73(a)(2)(v)(D)
Specify in Abstract below or in =
A. REQUIREMENT FOR This report is required per 10 CFR50.73(a)(2)(i)(B) based, in part, upon the 1A Engineered Safety Feature Chiller inoperable for a duration of greater than the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed by Technical Specification LCO 3.7.14 Condition A due to a failure to identify and respond to an out of specification operating parameter. Further, during the extended during which the 1 A ESF Chiller was inoperable (albeit unrecognized as inoperable), opposite train supported components as well as redundant room coolers on the Train B ESF Chiller and Room Cooler train were removed from service for un associated activities which resulted in a number of occasions during which Technical Specification LCO 3.0,3 should have been There were, therefore, periods of operation of plant during which the of two LCOs were inadvertently unrecognized thereby this report made pursuant to the of 10 CFR50.73(a)(2)(i)(B).
UNIT AT TIME EVENT During the period of the event the unit was in Mode 1, than described herein, there was no other equipment that contributed to the event.
DESCRIPTION
EVENT On August 17, 2012, a systems operator (SO) notified the Control Room the 1A ESF Chiller condenser pressure gauge indicated a vacuum of 12 inches of mercury with a vacuum of 15 inches of mercury specified on operating logs as the low vacuum limit. At the time, no procedural basis for this limit existed other than to document the reading in a condition report, The shift supervisor erroneously informed the SO that condenser pressure was one of the parameters which engineering personnel (Engineering) were monitoring and that a previous CR on this component existed, This misunderstanding was carried forward through subsequent shifts via the SO's log entry, During the next five calendar days, the condenser vacuum continued to decrease to 4 inches of mercury and subsequently stabilized at this value for an additional four calendar days, On August 26, 2012, an crew member the off-normal and initiated a CR. Engineering personnel, after consultation with the vendor, the Control Room the 1A ESF Chiller would not be able to peliorm its safety function under current conditions and the 1A ESF Chiller was promptly declared inoperable at 1437 on August 26, 2012, The 1A ESF Chiller was restored to operable and the LCO exited at 1930 on August 28,2012, causal analYSis of the event determined that the 1A ESF Chiller would be with r"'c::n",,~t to condenser vacuum provided condenser vacuum remained than or equal to 10 inches of mercury. Based on a review of operator rounds, the 1A ESF Chiller condenser vacuum decreased to less than 10 inches of mercury on August 19, 2012. An opportunity to this operability limit was missed by not evaluating the out of specification on 17,2012, The cause of the loss of condenser pressure was due to in conjunction with failure of the condenser purge compressor control circuit.
D. CAUSE OF EVENT
The underlying cause of the failure to comply with Technical Specification LCOs 3.7.14 and 3.0.3 event was a weakness in sensitivity to out of specification parameters by the shift supervisor, along with the associated failure to initiate a condition report documenting the out of specification parameter, as required by procedure. As a result of this error, the Operability Determination process was not conducted upon discovery of the condition, and the applicability of LCOs 3.7.14 and 3.0.3 was not recognized.
E. SAFETY ASSESSMENT
During the period of time the 1A ESF Chiller was inoperable but prior to the time of discovery, scheduled maintenance activities were performed on redundant train B equipment. As a result, on two occasions both trains of ESF Chillers and ESF Room Coolers were rendered concurrently inoperable placing the plant in a condition for which the applicable LCOs were not met and LCO 3.0.3 applied. These periods were longer than allowed by LCO 3.0.3 for plant operation in Mode 1. In addition, scheduled maintenance activities were performed on equipment supported by the redundant ESF Chiller and ESF Room Cooler Train that would have resulted in a determination of a Loss of Safety Function (LOSF) had the actual status of the 1A ESF Chiller been recognized and a LOSF evaluation been performed.
The Essential Chilled Water System (ECWS) and ESF Room Coolers are not included in the Vogtle Probabilistic Risk Assessment (PRA) model due to their negligible impact on the reliability of PRA credited functions as determined by room heat-up studies and the availability of alternate methods of room cooling. Based on a detailed review of Vogtle-specific room heat-up calculations and industry reference documents, it has been concluded that the ECWS-supported systems will be able to perform their safety function within the PRA credited mission time. In addition, a risk analysis of modeled components that were out of service during the period of inoperability of the 1A ESF Chiller was performed. The annualized increases in CDF and LERF were determined to be not significant.
F. CORRECTIVE ACTION
All Operations personnel were briefed on this event and reviewed the expectations for the performance of rounds. The event was entered into the plant's corrective action program and a causal analysis was completed. Procedures have been revised to strengthen the rigor and formality of supervisory review and oversight of operator rounds.
G. ADDITIONAL INFORMATION
- 1) Failed Components:
Unit 1 Train A ESF Chiller condenser purge compressor manufactured by Trane Company.
- 2) Previous Similar Events:
Although similar events related to monitoring of technical specification component parameters have been documented at Plant Vogtle, no similar occurrences of failure to initiate a condition report upon discovery were identified.
- 3) Energy Industry Identification System Code: Environmental Control Systems are coded by the area serviced. The 1A ESF Chiller served components in both the Auxiliary and Control Buildings.
The respective codes are: VF and VI.