05000338/LER-2009-001, Re Missile Shield Door Design Function Not Met Due to Improper Configuration
| ML093520394 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 12/14/2009 |
| From: | Stoddard D Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 09-664 LER 09-001-00 | |
| Download: ML093520394 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3382009001R00 - NRC Website | |
text
1 OCFR50.73 Virginia Electric and Power Company North Anna Power Station P. 0. Box 402 Mineral, Virginia 23117 December 14, 2009 Attention: Document Control Desk Serial No.:
09-664 U. S. Nuclear Regulatory Commission NAPS:
MPW Washington, DC 20555-0001 Docket No.: 50-338 50-339 License No.: NPF-4 NPF-7
Dear Sirs:
Pursuant to 10CFR50.73, Virginia Electric and Power Company hereby submits the following Licensee Event Report applicable to North Anna Power Station Units 1 and 2.
Report No. 50-338/2009-001-00 This report has been reviewed by the Facility Safety Review Committee and will be forwarded to the Management Safety Review Committee for its review.
Sincerely, Daniel G. Stoddard, P.E.
Site Vice President North Anna Power Station Enclosure Commitments contained in this letter: None cc:
United States Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303-8931 NRC Senior Resident Inspector North Anna Power Station
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSIO If tiVD BY OMB NO. 3150-0104 EXPIRES:
(9-2007)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE NORTH ANNA'POWER STATION, UNITS 1 AND 2 05000338 1 OF 3
- 4. TITLE Missile Shield Door Design Function Not Met Due To Improper Configuration
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY
' YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR FACILITY NAME DOCUMENTNUMBER NUMBER NO.
North Anna Unit 2 05000339 10 13 2009 2009
-- 001 --
00 12 14 2009 FACILITY NAME DOCUMENT NUMBER 12 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
E] 20.2201(b)
E]
20.2203(a)(3)(i)
[]
50.73(a)(2)(i)(C) 0]
50.73(a)(2)(vii)
[]
20.2201(d)
E] 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A)
E] 50.73(a)(2)(viii)(A) 1
[] 20.2203(a)(1)
[]
20.2203(a)(4)
H 50.73(a)(2)(ii)(B)
U] 50.73(a)(2)(viii)(B)
LI 20.2203(a)(2)(i)
[] 50.36(c)(1)(i)(A)
U] 50.73(a)(2)(iii)
[
50.73(a)(2)(ix)(A)
- 10. POWER LEVEL [I
'20.2203(a)(2)(ii)
LI 50.36(c)(1)(ii)(A)
[F] 50.73(a)(2)(iv)(A)
[F]
50.73(a)(2)(x)
LI 20.2203(a)(2)(iii)
[I]
50.36(c)(2)
U]
50.73(a)(2)(v)(A)
[]
73.71(a)(4)
U] 20.2203(a)(2)(iv)
E] 50.46(a)(3)(ii)
U]
50 73(a)(2)(v)(B)
[]
73.71(a)(5)
E] 20.2203(a)(2)(v)
U] 50.73(a)(2)(i)(A)
U]
50.73(a)(2)(v)(C)
[]
OTHER 100%
U] 20.2203(a)(2)(vi)
U] 50.73(a)(2)(i)(B)
[]
50.73(a)(2)(v)(D)
VOLUNTARY LER
- 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME TELEPHONE NUMBER (Include Area Code)
E. S. Hendrixson, Director Station Safety and Licensing (540) 894-2108I
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX I
FACTURER TO EPIX B
BI DR M506 Y
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR
[]
SUBMISSION El YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
IZ NO DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
On October 13, 2009, with Units 1 and 2 operating at 100 percent power (Mode 1), an engineering evaluation confirmed the east missile shield door for the Service Water Valve House (SWVH) would not have performed its design function during a design basis tornado event. The east missile shield door locking pins were not engaged and the security hasp and lock would not be capable of meeting the design loading. Station procedure 0-AP-41, Severe Weather Conditions, did not ensure the SWVH missile shield doors were properly secured in the event of a tornado or hurricane event. This could result in the east missile shield door swinging outward in a tornado missile event and a tornado missile could have entered the SWVH and disabled the electric power supply to the Service Water (SW) motor operated valves (MOV). This could have prevented the SW System from being able to mitigate the consequences of an accident and is reportable pursuant to 10 CFR 50.73 (a)(2)(v)(D). This event posed no significant safety implications since the SW spray arrays were verified to be in operation during each entry into the severe weather condition and capable of mitigating the consequences of an accident. Therefore, the health and safety of the public were not affected by this event.
NRC FORM 366 (9-2007)
PRINTED ON RECYCLED PAPER (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A) (17) included in the AP. Had a condition occurred which required the missile shield doors to be closed and locked the SWVH missile shield doors would not have been verified in the required configuration.
The SWVH missile shield doors are the only missile shield barriers onsite with a swing door. All other missile shield doors are a rolling/sliding design. It was.not understood that while the SWVH missile shield doors were fully closed and locked with the security hasp that they would not perform their tornado design function when the locking pins were not engaged. None of the other rolling/sliding missile barrier doors have this unique locking pin design. This knowledge deficiency along with the absence of SWVH missile shield door verification in the abnormal procedure was determined to be the cause.
4.0 IMMEDIATE CORRECTIVE ACTION(S)
Upon identification of the deviating condition the SWVH missile shield door locking pins were engaged and the door was posted to prevent its use for routine access.
Subsequently, repairs to the SWVH missile shield door locking pins were completed and the door was returned to service.
5.0 ADDITIONAL CORRECTIVE ACTIONS
The abnormal procedure was revised to include verification of the SWVH missile shield doors and require all equipment in the areas affected by an inoperable missile shield door be declared inoperable and associated actions entered.
Training is being provided regarding the knowledge deficiency for safety functions the missile shield barriers are required to maintain. A table is being developed for inclusion in the Technical Requirements Manual that will list missile shield doors and the required compensatory actions.
6.0 ACTIONS TO PREVENT RECURRENCE The actions taken regarding abnormal procedure revision, personnel training and inclusion of a missile shield door list in the TRM will prevent recurrence.
7.0
SIMILAR EVENTS
None.
8.0 ADDITIONAL INFORMATION
Component information:
Mark Number 1-BLD-MBAR-WV26-2 Manufacturer Mosler, Inc.
Model Number B-960000 1/2
Description
Service Water Valve House Steel Swing Door (Missile Barrier)PRINTED ON RECYCLED PAPER