05000424/LER-2009-001, Ultimate Heat Sink Inoperable Longer than Allowed by Technical Specifications
| ML093140292 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 11/09/2009 |
| From: | Tynan T Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-09-1653 LER 09-001-00 | |
| Download: ML093140292 (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) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 4242009001R00 - NRC Website | |
text
Tom Tynan Suuthern Nuclear Vice President -Vogtle Operating Company, Inc.
7821 R'ver Road Waynesboro, Georgia 30830 Te 7fJ3 826.3151 Fax 7]58263321 SOUTHERN COMPANY November 9, 2009 Erl.l:rgy to Serve Your WOrld" Docket No.:
50-424 NL-09-1653 U. S. Nuclear Regulatory Commission ATIl\\!: Document Control Desk Washington, D. C, 20555-0001 Vogtle Electric Genera1ing Plant-Unit 1 Licensee Event Report 1-2009-001 Ultimate Heat Sink Inoperable Longer Than Allowed By Technical Specifications Ladies and Gentlemen:
In accordance with the reqUirements of 10CFR50.73(a)(2)(i)(B), Southern Nuclear Operating Company (SNC) is submitting the enclosed Ucensee Event Report.
Tl1is letter contains no NRC commitments. If you have any questions, please advise.
Sincerely, T. E.Tynan Vice President Vogtle TETITMH/sdc Enclosure: LER 1-2009-001 cc: Southern Nuclear Operating Company Mr. J. T. Gasser, Executive Vice President Mr. T. E. Tynan. Vice President Vogtle Ms. P. M. Marino, Vice President Engineering RType: CVC7000
U. S. Nuclear Regulatory Commission Log:
Page 2 U. S. Nuclear Regulatory Commission Mr. L. A Reyes, Regional Administrator Ms. D. N. Wright, NRR Project Manager - Vogtle Mr. M. Cain, Senior Resident Inspector - Vagtle
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION.&.PPROVED BY OMS: NO. 3150-0104 EXPIRES: 061311:2Q10
- "~"'(I7)
Estlmale<! burden per response to complV w~1l this mafldlliaty co"ec~{ln request tiC hours. Reponed lessons !earned are incorporated into the licensing process and fed back 10 Induslry. Send oomrNmts refrdio9 burden estimate 10 the Records and FOiAIPrivacy SeN1ce Brar)ch ( *5 F52l. U.S.
LICENSEE EVENT REPORT (LER)
Nuclear R:;/1ulatOry CommisskJo. Washington. DC :;>0555-0001, or br, internet e*maillo ill OColl9Cts@nrc80v. and to the Desk Officer. Office of In ocmatk>n and Regula10ry Allairs. NE B*l0202. (3150*0104). Office of Managem!!nl and Budg!!t. Washington. DC 20503. It e mealls used to impose an inlcrmation collection does not display a GurrerTlly valid OMB conlr<ll numbs*. Ihe NRC may nut. COnd,Yr~,?:'"sponsor. and a person i$ not fequirad 10 respond to. tllll
- 13. PAGE Vogtle Electric Generating Plant - Unit 1 OSOOO 424 1 OF 4
- 4. TITLE Ultimate Heat Sink Inoperable Longer than Allowed by Technical Specifications
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED
"'ACIU"Y NAME DOCKET NUMBER I
SEQUENTIALIREV MONTH DAY YEAR YEA~
MONTH DAY YEAR NUMBER NO.
05000 FACILITY NIIM!'
IDOC~ET 'lUMBER 09 16 2009 2009 001 0
11 09 2009 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMmED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all thai apply) o 20.2201(b) o 20.2203(a){S){i) o 50.73(a)(2)(i)(C) o 50.73(a)(2)(vn}
1 o 20 220 1(d) o 20.2203(a){3)(ii) o 50.73{a)(2)(ii){A) o 50.73(a)(2)(viiil(A) o 20.2203(a}(l) o :20.2:203(a)(4) o 50.73(a)(2)(1I)(8) o 50.73(a}(2)(viilJ(B) o 20.2203(a}(2)(i) o 50.36(c)(1 )(i):A) o 50.73{a)(2)(iii) o 50.73(a)(2)(ix}(A)
- 10. POWER LEVEL o 20. 2203(a}(2)(jil o 50.36{c)(1 )(iI)(A) o 50.73(a)(2)(iv)(A) o 50.73(a){2)1x) o 20.2203(a}(2)(1U) o 50.36(c)(2) o 50.73(a)(2){v)(A) o 73.71(a){4) o 20.2203(a}(2)(jv) o 50.46(a)(3){ii) o 50.73(a)(2)(v)(S) o 73.71 (a}(5) 094 o 2O.2203(a}(2)(v) o 50.73(a)(2){I)(A) o 50.73{a)(2)(v)(C) o OTHER o 2O.2203{a}(2)(vi) 181 50.73(a)(2){i)(B) o 50.73{a)(2)(v)(D)
Specity in Abslmct below or in N'Fl(: Form ~A
- 12. LlCENSEE CONTACT FOR THIS LER FAC'UTVf\\"AME.
1(;;;);;~~:E1R~~IUd& AlQa COOQ.I Vogtle Electric Generating PlanVMark Hickox, Principal Licensing Engineer,
MANU*
REPORTABLE MANiJ*
REPORTABLE
CAUSE
SYSTEM COMPONENT
CAUSE
SYSTEM COMPONENT FACTURER TO EPIX FACTURER TO EPIX E
81 ISV A391 N
I
- 14. SUPPLEMENTAl. REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR SUBMISSION o YES (II y~s. complete 15. EXPECTED SUBMISSION DATE) 181 NO DATE IABSTRACT (Limit to 1400 spaces, i./I.* approximately 15 single-spaced typewritt&n lines)
In preparation for Vogtle Electric Genemting Plant (VEGP) refueling outage (IR 15), on Wednesday.
September 16 at approximately 1357 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.163385e-4 months <br /> Eastern Daylight Time (EDT), Nuclear Service Cooling Water (NSCW) flow to the B train auxiliary containment and reactor cavity cooler was isolated. The isolation valves were closed to install expansion joints between the safety related NSCW piping and the non safety related normal chilled water piping. During installation of the expansIOn joints it was noted thai there was significant leakage past the manual valves that had been closed to isolate the NSCW
~ystem. AI the time of inslallation of the expansion joints, the potential consequences the leakage could ha\\'e on the Operability of the Ultimate Heat Sink (UHS), was not recognized. Subsequcnlly, on Saturday. September 19, at 0306 hours0.00354 days <br />0.085 hours <br />5.059524e-4 weeks <br />1.16433e-4 months <br /> EDT, it was determined that leakage pas.t the NSCW manual isolation valves was in excess of analyzed limits and Technical Specification Required Action Statement 3.7.9.A was entered. Unit 1 was subsequently shutdown for the :;cheduled refueling outage on Sunday, September 20, 2009. However. since there was firm evidence that there was excessive leakage past the manuul isolation valves at the time the expansion joints were installed, Unit 1 operated in a condition longer than allowed by Ihe Technical Specifications.
NRC FORM 366 (9*2007)
PRINTED ON RECYCLED PAPER (Jf mors space is (squired. USB additionaf COpiBS of (If more space is required, use additional copi8S of NRC Form 36BA) down. During the time the B train NSCW manual isolation valves were leaking, all components serviced by the A train NSCW system were operable. In addition. the NSCW system has an inter-tie line that prO\\*ides makeup water from the operating train to the idle train of NSCW. This design feature prevents waler hammer by ensuring the idle train remains full of water which could result from minor leakage losses within the system. Once B train of NSCW was shutdown, leakage paSot the closed manual isolation valves would have resulted in the annunciation of the inter-tie high flow alarm. The control room operafors would have responded to the high flow alann and followed the guidance in the annunciator response procedure and isolate<! the inter-lie line. Thb action would have terminated the inventory loss. Therefore, during a design ba!'.is LOCA coincident with a LOSP, and assuming the expansion joints failed as u result of a seismic event, there would stil1 have been sufficient inventory in the NSCW basins to meet the 30 day mission time. Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the accident, B train NSCW would have been secured and
~hortly thereafter the inter-tie line would have been isolated. These actions would have terminated the loss of UHS inventory. The A train NSCW system would ha ve continued to operate. There was. sufficient margin available to account for the loss of basin inventory as a result of the leaking manual isolation valves for rhe 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period without challenging the 30 day mission rime. Therefore. this event did not result in a loss of safety function.
F. CORRECTIVE ACTIONS
The corrective actions to preclude re.currence of this event include:
I. The NSCW manual isolation valves were reworked during IR 15 to minimize seat leakage.
- 2. The system operating procedure will be revised to include requirements to mea<;ure leakage past the NSCW manual isolation valves prior to removing the blind flanges to ensure the leakage past the manual isolation valves is within acceptable limits. The estimated completion date for this corrective action is December 15, 2009.
G. ADDITIONAL INFORMATION
I. Failed Components:
Anchor/Darling 8" Wafer Style Butterfly valves
- 2. Previous Similar Event:
None
- 3. Energy Industry Identification System Codes:
Ultimate Heat Sink-BS Knclear Service Cooling Water System-BI NRC FORM 3!l6A(9-20011 PRIr-.TED ON RECYCLED PAPrRI