05000397/LER-2013-001, Regarding Secondary Containment Inoperable Due to Both Airlock Doors Being Open
| ML13079A261 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 03/08/2013 |
| From: | Hettel W Energy Northwest |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GO2-13-041 LER 13-001-00 | |
| Download: ML13079A261 (4) | |
| 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 |
| 3972013001R00 - NRC Website | |
text
J W. Grover Hettei ENERGY Columbia Generating Station P.O. Box 968, PE23 Richland, WA 99352-0968 J NORTHW EST Ph. 509.377.8311 I F. 509.377.4150 wghettel@energy-northwest.com March 8, 2013 G02-13-041 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001
Subject:
COLUMBIA GENERATING STATION, DOCKET NO. 50-397 LICENSEE EVENT REPORT NO. 2013-001-00
Dear Sir or Madam:
Transmitted herewith is Licensee Event Report No. 2013-001-00 for Columbia Generating Station. This report is submitted pursuant to 10 CFR 50.73(a)(2)(v)(C) and (D), which requires the reporting of any condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to: control the release of radioactive material and mitigate the consequences of an accident.
There are no commitments being made to the NRC by this letter. If you have any questions or require additional information, please contact Mr. ZK Dunham at (509) 377-4735.
Respectfully, WG Hettel Vice President, Operations Attachment: Licensee Event Report 2013-001-00 cc: NRC Region IV Administrator NRC NRR Project Manager NRC Senior Resident Inspector/988C AJ Rapacz - BPA/1 399 WA Horin - Winston & Strawn A t4C
- - j a NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB NO. 3150-0104 EXPIRES 10/31/2013 (10-2010)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Columbia Generating Station 05000397 1 OF 3
- 4. TITLE Secondary Containment Inoperable due to both Airlock Doors being Open
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED YSEQUENTIAL I REV MONTH DAY YEAR FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER MON.
DAY0YE0 FACILITY NAME DOCKET NUMBER 01 07 2013 2013 -001 -00 03 08 2013 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 1 El 20.2201(b)
El 20.2203(a)(3)(i)
F1 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii)
El 20.2201(d)
El 20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
[I 50.73(a)(2)(viii)(A)
[1 20.2203 (a)(1)
[I 20.2203(a)(4)
El 50.73(a)(2)(ii)(B)
[I 50.73(a)(2)(viii)(B)
El 20.2203(a)(2)(i)
El 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
El 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) 100 [E
20.2203(a)(2)(iii)
[E 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4)
[E 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71 (a)(5)
El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A) 9 50.73(a)(2)(v)(C)
El OTHER El 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B) 0 50.73(a)(2)(v)(D)
Specify in Abstract below or in First Root Cause: A legacy design weakness for the Secondary Containment airlock door interlocks allows conditions where both the inner and outer doors can be opened at the same time.
Second Root Cause: Implementation of TSTF-1 8-A, Rev 1, at Columbia changed the wording of TS Bases for SR 3.6.4.1.2 and SR 3.6.4.1.3, reducing the clarity of the description of conditions that define Secondary Containment operability.
FURTHER CORRECTIVE ACTION A design change is being evaluated that includes replacing the existing mechanical locks on all Secondary Containment airlock inner doors with a more reliable door locking device, improving the interlock logic to eliminate current design imperfections, and installing warning lights on the outside of the airlock to warn personal when the airlock is in use.
The TS Bases for SR 3.6.4.1.2 and SR 3.6.4.1.3 is being revised to ensure that the wording clearly identifies that Secondary Containment operability requires that one door in each airlock be closed at all times when Secondary Containment is required.
ASSESSMENT OF SAFETY CONSEQUENCES
There was no equipment damage, injuries or dose exposure to station personnel. There was no change in plant status or operating condition and there was no actual risk to the public at any time. There was no impact to public health and safety as the Primary Containment was intact with Primary Containment Isolation Valves operable. The Reactor Building Ventilation System maintained the designed negative pressure for Secondary Containment during the event.
There was a potential significance if there had been an event where the Primary Containment failed to isolate concurrent with a loss of coolant accident such that radioactive materials were released to the Reactor Building. Having both Reactor Building airlock doors open would potentially provide a release path for radioactive materials to enter the external environment or would inhibit the ability to draw down Secondary Containment within the time frame assumed in the dose analysis.
SIMILAR EVENTS
A similar event occurred at Columbia on December 30, 2012 (Event Notification 48639) and reported in LER 2012-007-00.
ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) INFORMATION CODES EIIS codes are bracketed [] where applicable in the narrative.
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