05000259/LER-2008-001, Loss of Secondary Containment When the Reactor Vent Zone Dampers Failed to Close on a Group 6 Containment Isolation Signal
| ML083120080 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 11/03/2008 |
| From: | West R Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| IR-08-001 LER 08-001-00 | |
| Download: ML083120080 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 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)(iii) 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)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 2592008001R00 - NRC Website | |
text
Tennessee Valley Authority, Post Office Box 2000, Decatur, Alabama 35609-2000 November 03, 2008 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Stop: OWFN, P1-35 Washington, D. C. 20555-0001 10 CFR 50.73 TENNESSEE VALLEY AUTHORITY - BROWNS FERRY NUCLEAR PLANT (BFN) -
UNIT 1 - DOCKET 50-259 - FACILITY OPERATING LICENSE DPR LICENSEE EVENT REPORT (LER) 50-259/2008-001 The enclosed report provides details of a loss of secondary containment when the reactor vent zone dampers failed to close on a Group 6 containment isolation signal generated during testing activities.
TVA is reporting this in accordance with 10 CFR 50.73(a)(2)(v)(C), as any event or condition that could have prevented the fulfillment of the safety function of structures that are needed to control the release of radioactive material. There are no commitments contained in this letter.
Wincesrely, R.
. Wes Site Vice President, BFN cc: See page 2 e--ý
U.S. Nuclear Regulatory Commission Page 2 November 03, 2008 Enclosure cc (Enclosure):
Ms. Eva A. Brown, Project Manager U.S. Nuclear Regulatory Commission (MS 08G9)
One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852-2739 Eugene F. Guthrie, Branch Chief U.S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303-8931 NRC Resident Inspector Browns Ferry Nuclear Plant 10833 Shaw Road Athens, Alabama 35611-6970
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 08/31/2010 (9-2007)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information digits/characters for each block) collection.
- 3. PAGE Browns Ferry Unit 1 05000259 1 of 4
- 4. TITLE: Loss Of Secondary Containment When The Reactor Vent Zone Dampers Failed To Close On A Group 6 Containment Isolation Signal.
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SEQUNTIA R
FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SUE REV MONTH DAY YEAR None N/A FACILITY NAME DOCKET NUMBER 09 03 2008 2008 001 00 11 03 2008 None N/A
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
El 20.2201(b)
El 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii)
[1 20.2201(d)
El 20.2203(a)(3)(ii)
[I 50.73(a)(2)(ii)(A)
El 50.73(a)(2)(viii)(A)
E] 20.2203(a)(1)
El 20.2203(a)(4)
[I 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
[I 20.2203(a)(2)(i)
[I 50.36(c)(1)(i)(A)
[I 50.73(a)(2)(iii)
[I 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL El 20.2203(a)(2)(ii)
El 50.36(c)(1)(ii)(A)
El 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
[I 20.2203(a)(2)(iii)
El 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4)
[3 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71(a)(5) 100 El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(C)
El OTHER El 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A) (17)
As demonstrated in this event, Operations, using control room indication, determined that the dampers did not isolate and initiated immediate corrective actions to restore secondary containment, thus, minimizing the effect of the loss of secondary containment. Therefore, TVA concludes the health and safety of the public was not affected by this event.
VI.
CORRECTIVE ACTIONS
A.
Immediate Corrective Actions
The dampers were closed and placed under administrative controls.
B.
Corrective Actions to Prevent Recurrence (1)
TVA replaced the solenoid valves for dampers 1 -DMP-64-42 and 1 -DMP-64-43. TVA also found Unit 1 Reactor Zone Isolation Damper solenoids (1 -FSV-64-13 and 1-FSV-64-14) could be susceptible to similar failure. Accordingly, these have been replaced.
VII. ADDITIONAL INFORMATION
A.
Failed Components ASCO Model NP 8320 14 inch 150 psi/1 20 volt solenoid valves.
B.
Previous LERs on Similar Events No recent LERs have been issued due to solenoid valve failures. The previous failure discussed in this report required only entry into an LCO. It did not meet the criterion for a report to the NRC.
C.
Additional Information
Corrective action document for this report is PER 151814.
D.
Safety System Functional Failure Consideration:
This event involved a safety system functional failure as referenced in NEI 99-02 and 10 CFR 50.73(a)(2)(v). This failure will be included in Performance Indicator Reporting in accordance with NEI 99-02.
E.
Scram With Complications Consideration:
This event was not a complicated scram according to NEI 99-02.
VIII. COMMITMENTS
None.
(1) TVA does not consider the corrective action the regulatory requirement. The completion of the action will be tracked in TVAs Corrective Action Program.