05000285/LER-2013-016, Regarding Reporting of Additional High Energy Line Break Concerns

Regarding Reporting of Additional High Energy Line Break Concerns

ML14015A373
Person / Time
Site:	Fort Calhoun
Issue date:	01/06/2014
From:	Cortopassi L Omaha Public Power District
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LIC-19-0180 LER 13-016-00
Download: ML14015A373 (4)

LER-2013-016, Regarding Reporting of Additional High Energy Line Break Concerns

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(8) 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(8) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(i) 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)(iii) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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 10 CFR 50.73(a)(2)(ii)
2852013016R00 - NRC Website

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jjjjjjjj Omaha I'IIIIIIc Power IJIBIrfcI 444 South 1 (/h Street Mall Omaha, NE 68102-2247 UC-13-0180 January 6,2014 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

Reference:

Docket No. 50-285

Subject:

licensee Event Report 2013-016, Revision 0, for the Fort Calhoun Station Please find attached Licensee Event Report 2013-016, Revision O. This report is being submitted pursuant to 10 CFR 50.73(a)(2)(ii)(8), 10 CFR 50.73(a)(2)(v), 10 CFR 50.73(a)(2)(i)(8), 10 CFR 50.73(a)(2)(vii), and 10 CFR 50.73(a)(2)(ix)(A). There are no new commitments being made in this letter.

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

ouis P. Cortopassi Site Vice President and CNO LPC/epm Attachment c:

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

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 (10-2010)

Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industr~ Send comments regarding burden estinate to the FOIA/Privacy Section ( -5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to LICENSEE EVENT REPORT (LER) infocollects.resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150"()104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information (See reverse for required number of collection does not display a currently valid OMB control m.rnber, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the information collection.

13. PAGE Fort Calhoun Station 05000285 1 OF 3

4. TITLE Reporting of Additional High Energy Line Break Concerns

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 11 05 2013 2013 016 -

0 01 06 2014 05000

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Checkallthatapply) 5 D

20.2201(b)

D 20.2203(a)(3)(i)

D 50.73(a)(2)(i)(C) 181 50.73(a)(2)(vii)

D 20.2201(d)

D 20.2203(a)(3)(ii)

D 50.73(a)(2)(ii)(A) 181 50.73(a)(2)(viii)(A)

D 20.2203(a)(1)

D 20.2203(a)(4) 181 50.73(a)(2)(ii)(B)

D 5O.73(a)(2)(viii)(B)

D 20.2203(a)(2)(i)

D 5O.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 5O.73(a)(2)(v)(A)

D 73.71(a)(4) 0 D

20.2203(a)(2)(iv)

D 5O.46(a)(3)(ii) 181 50.73(a)(2)(v)(B)

D 73.71(a)(5)

D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A) 181 50.73(a)(2)(v)(C)

D OTHER D

20.2203(a)(2)(vi) 181 50.73(a)(2)(i)(B) 181 50.73(a)(2)(v)(O)

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 (If yes, complete 15. EXPECTED SUBMISSION DATE) 181 NO SUBMISSION DATE

~BSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)

On October 18, 2013, as part of an extent of condition for LERs 2012-017 and 2013-011, Fort Calhoun Station (FCS) personnel identified a potential additional high energy line break (HELB) concern with the piping associated with the letdown heat exchanger (LDHX). Subsequently on November 5, 11, 16, and 20, additional HELB impacts were also identified. These impacts involved increased loads on supports in the piping subsystem MS-4099 (main steam supply to FW-10), high energy line cracking (HELC) related to auxiliary steam in various rooms in the power block, the assumptions made regarding diesel generator operability during a HELB, and the quality of the steam to FW-10, the steam-driven auxiliary feedwater pump.

It was previously determined and reported that FCS did not fully implement anc:llor maintain the Electrical Equipment Qualification (EEQ) program to meet the requirements of 10 CFR 50.49. As a consequence, the equipment included in the EEQ program, the systems included in the High Energy Line Break (HELB) Analysis and the environmental conditions used by the EEQ program have not been maintained current or in an auditable manner. In addition to the corrective actions (CA) to resolve the EEQ/HELB program issues previously reported, additional CAs are being pursued to address the individual conditions listed above.

NRC FORM 366 (10-2010)

BACKGROUND

2. DOCKET YEAR 05000285 2013

6. LER NUMBER

3. PAGE 2

OF I SEQUENTIAL I REV NUMBER NO.

016 o

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

EVENT DESCRIPTION

On October 18, 2013, as part of an extent of condition for LERs 2012-017 and 2013-011, Fort Calhoun Station (FCS) personnel identified a potential additional high energy line break (HELB) concern with the piping associated with the letdown heat exchanger (LDHX). Subsequently on November 5, 11, 16, and 20, additional impacts were also identified. These impacts involved increased loads on supports in the piping subsystem MS-4099 (main steam supply to FW-10, the steam-driven auxiliary feedwater pump), high energy ling cracking (HELC) related to auxiliary steam in various rooms in the power block, the assumptions made regarding diesel generator operability during a HELB, and the quality of the steam to FW-10.

At approximately 1938 Eastern Daylight Time (EST) on October 18, 2013, an 8-hour notification was made to the Headquarters Operations Office, under 10 CFR 50.72(b)(3)(ii)(A), Degraded Condition, reporting the initial HELB impact from the LDHX piping.

These events are being submitted as a separate LER due to being discovered in excess of 60 days from LER 2013-011. This report is being submitted pursuant to 10 CFR 50.73(a)(2)(ii) any event or condition that resulted in: (B) the nuclear power plant being in an unanalyzed condition that significantly degraded plant safety; 10 CFR 50.73(a)(2)(v) any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to: (B) remove residual heat; (C) control the release of radioactive material; and (D) mitigate the consequences of an accident, 10 CFR 50.73(a)(2)(i)(B) any operation or condition which was prohibited by the plant's Technical Specifications, 10 CFR 50.73(a)(2)(vii) any event where a single cause or condition caused at least one independent train or channel to become inoperable in multiple systems or two independent trains or channels to become inoperable in a single system designed to: (B) remove residual heat; (C) control the release of radioactive material; and (D) mitigate the consequences of an accident, and 10 CFR 50. 73( a)(2)(ix)(A) any event or condition that as a result of a single cause could have prevented the fulfillment of a safety function for two or more trains or channels in different systems that are needed to: (2) remove residual heat; (3) control the release of radioactive material; and (4) mitigate the consequences of an accident.

CONCLUSION It was previously determined and reported in OPPD LERs 2012-017 and 2013-011 that FCS did not fully implement and/or maintain the electrical equipment qualification (EEQ) program to meet the requirements of 10 CFR 50.49. As a consequence, the equipment included in the EEQ program, the systems included in the HELB analysis and the environmental conditions used by the EEQ program have not been maintained current or in an auditable manner.

CORRECTIVE ACTIONS

In addition to the corrective actions (CA) to resolve the EEQ/HELB program issues previously reported, additional CAs are being pursued to address the individual conditions.

OF A pipe whip restraint, CHVS-253, has been added to piping system CH-4106 to eliminate the letdown heat exchanger line break concern. (Engineering Change 62388, CH-7 Letdown Heat Exchanger Inlet Pipe Whip Restraint).

Ten existing pipe supports were modified and three additional supports were added to piping subsystem MS-4099 to address pipe loading concerns. (Engineering Change 53202, Modify Piping and Supports for FW-10 MS Supply for HELB Concerns).

Auxiliary steam has been isolated to Rooms 63, 64, 65, 69, and the intake structure to eliminate the effects of high energy line cracks associated with the auxiliary steam piping in these locations.

This includes the diesel generator operability concerns during a HELB.

Two flood barriers were installed in Room 81 to protect the steam supply to FW-10 from being quenched by possible flooding. (Engineering Change 62391, FW-10 Steam Supply Line A and B HELB Flood Barriers).

SAFETY SIGNIFICANCE

The conditions identified had the potential to impact both of the emergency diesel generators, the raw water pumps, containment outboard isolation for penetrations M-75 through M-88, component cooling water, and the steam-driven auxiliary feedwater pump FW-10.

SAFETY SYSTEM FUNCTIONAL FAILURE This'does not represent a new safety system functional failure in accordance with NEI 99-02, Revision 7, as it has previously been reported in LERs 2012-017 and 2013-011.

PREVIOUS EVENTS LER 2012-002 2012-009 2012-015 2013-011 Subject Inadequate Qualifications for Containment Penetrations Renders Containment Inoperable Inoperable Equipment due to Lack of Environmental Qualifications Electrical Equipment Impacted by High Energy Line Break Outside Containment Inadequate Design for High Energy Line Break in Rooms 13 and 19 of Auxiliary Building The condition discussed in this LER was identified during the extent of condition from the investigation in response to the HELB/EQ programic issues. The conditions identified are considered latent conditions that would not have been corrected by previous actions taken to prevent recurrence. 3