05000285/LER-2012-009-01, Inoperable Equipment Due to Lack of Environmental Qualifications

Inoperable Equipment Due to Lack of Environmental Qualifications

ML13308C235
Person / Time
Site:	Fort Calhoun
Issue date:	10/31/2013
From:	Cortopassi L Omaha Public Power District
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LIC-13-0097 LER 12-009-01
Download: ML13308C235 (3)

LER-2012-009, Inoperable Equipment Due to Lack of Environmental Qualifications

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)(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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2852012009R01 - NRC Website

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ujjjju Omaha Public Power District 444 South 16th Street Mall Omaha, NE 68102-2247 LlC-13-0097 October 31,2013 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

Reference:

1. Docket No. 50-285

2. Letter from OPPD (D. J. Bannister) to NRC (Document Control Desk) dated July 23, 2012 (LlC-12-0105)

Subject:

Licensee Event Report 2012-009, Revision 1, for the Fort Calhoun Station Please find attached Licensee Event Report 2012-009, Revision 1. The original condition no longer represents a safety system functional failure and is being recharacterized as not reportable and submitted as a voluntary report. No commitments are being made in this letter.

If you should have any questions, please contact Terrence W. Simpkin, Manager, Site Regulatory Assurance, at (402) 533-6263.

Sincerely, Lows P. Cortopassi Site Vice President and CNO LPC/rjr/epm Attachment c:

M. L. Dapas, NRC Regional Administrator, Region IV J. M. Sebrosky, NRC Sr. Project Manager L. E. Wilkins, NRC Project Manager J. C. Kirkland, NRC Sr. Resident Inspector Employment with Equal Opportunity

NRC FORM 366 u.s. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: 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

13. PAGE Fort Calhoun Station 05000285 1 OF 2

4. TITLE Inoperable Equipment due to Lack of Environmental Qualifications

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NUMBER NO.

MONTH DAY YEAR 05000 FACILITY NAME DOCKET NUMBER 12 13 2011 2012 - 009 -

1 10 31 2013 05000

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 5 D 20.2201(b)

D 20.2203(a)(3)(i)

D 50.73(a)(2)(i)(C)

D 50.73(a)(2)(vii)

D 20.2201(d)

D 20.2203(a)(3)(ii)

D 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A)

D 20.2203(a)(1)

D 20.2203(a)(4)

D 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B)

D 20.2203(a)(2)(i)

D 50.36(c)(1 )(i)(A)

D 50.73(a)(2)(iii)

D 50.73(a)(2)(ix)(A)

10. POWER LEVEL D 20.2203(a)(2)(ii)

D 50.36(c)(1 )(ii)(A)

D 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x)

D 20.2203(a)(2)(iii)

D 50.36(c)(2)

D 50.73(a)(2)(v)(A)

D 73.71(a)(4) 0 D 20.2203(a)(2)(iv)

D 50.46(a)(3)(ii)

D 50.73(a)(2)(v)(B)

D 73.71 (a)(5)

D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A)

D 50.73(a)(2)(v)(C) 181 OTHER D 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B)

D

50. 73(a)(2)(v)(D)

Voluntary Report

12. LICENSEE CONTACT FOR THIS LER FACILITY NAME ITELEPHONE NUMBER (Include Area Code)

Erick Matzke 402-533-6855 CAUSE SYSTEM COMPONENT MANU-REPORTABLE

CAUSE

SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TO EPIX

14. SUPPLEMENTAL REPORT EXPECTED

15. EXPECTED MONTH DAY YEAR DYES (/fyes, complete 15. EXPECTED SUBMISSION DATE) 181 NO SUBMISSION DATE IABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)

On December 13, 2011, it was identified that the current analysis of record for the Main Steam Line Break (MSLB) inside containment identified a peak temperature of 358.6 degrees Fahrenheit (F) and the Electrical Environmental Equipment Qualification (EEQ) evaluation assumed a maximum temperature of 401 degrees F. It was also identified that the MSLB temperature has a longer exposure time than the EEQ temperature of approximately 160 seconds. However, no evaluation or analysis could be found to address why the original EEQ assumptions remained valid as the longer exposure time of the MSLB analysis could result in an adverse impact on environmentally qualified equipment. This condition was identified when Fort Calhoun Station was shutdown and defueled.

FCS performed a thermal lag analysis to determine the impact of the longer exposure time. The results show that the additional exposure time of the lower MSLB temperature did not adversely affect the EEQ analysis as originally assumed in Event Notification 47900 (10 CFR 50.72(b)(3)(ii)(B)). The results of the thermal lag analysis are being documented in the updated program basis documentation.

The EEQ Harsh Files for the affected equipment have been revised.

The original condition no longer represents a safety system functional failure and this condition is being submitted as a voluntary report.

NRC FORM 366 (10-2010)

BACKGROUND

2. DOCKET YEAR 05000285 2012

6. LER NUMBER

3. PAGE 2

OF I

SEQUENTIAL I REV NUMBER NO.

009 1

Fort Calhoun Station (FCS) is a two-loop reactor coolant system of Combustion Engineering (CE) design.

EVENT DESCRIPTION

On December 13, 2011, it was identified that the current analysis of record for the Main Steam Line Break (MSLB) inside containment identified a peak temperature of 358.6 degrees Fahrenheit (F) and the Electrical Environmental Equipment Qualification (EEQ) evaluation assumed maximum temperature of 401 degrees F. It was also identified that the MSLB temperature has a longer exposure time than the EEQ temperature of approximately 160 seconds. However, no evaluation or analysis could be found to address why the original EEQ assumptions remained valid as the longer exposure time of the MSLB analysis could result in an adverse impact on environmentally qualified equipment. This condition was identified when Fort Calhoun Station was shutdown and defueled and entered into the station's corrective action program as Condition Report 2011-10129.

The condition identified on December 13, 2011, was initially reported via Event Notification 47900 as an unanalyzed condition (10 CFR 50.72(b)(3)(ii)(B>> on May 04,2012. The initial LER submittal was made on July 23, 2012. These notifications were determined to have been made late.

However, FCS subsequently performed a thermal lag analysis to determine the impact of the longer exposure time. The results show that the additional exposure time of the lower MSLB temperature does not adversely affect the EEQ analysis as originally assumed. Therefore, the original condition no longer represents a safety system functional failure and is being recharacterized as not reportable.

For completeness, this event report has been updated and is being submitted as a voluntary LER.

CONCLUSION The thermal lag analysis shows that the additional exposure time of the lower MSLB temperature did not adversely affect the EEQ analysis as originally assumed. Therefore, the condition is being recharacterized as not reportable.

CORRECTIVE ACTIONS

The results of the thermal lag analysis are being documented in the updated program basis documentation. The EEQ Harsh Files for the affected equipment have been revised.

SAFETY SIGNIFICANCE

The thermal lag analysis showed that the additional exposure time of the lower MSLB temperature did not adversely affect the EEQ analysis as originally assumed. Therefore, no reportable condition existed.

SAFETY SYSTEM FUNCTIONAL FAILURE This event does not result in a safety system functional failure in accordance with NEI-99-02.

PREVIOUS EVENTS None 2