05000285/LER-2013-005-01, Regarding Control Room HVAC Modification Not Properly Evaluated

Regarding Control Room HVAC Modification Not Properly Evaluated

ML13213A069
Person / Time
Site:	Fort Calhoun
Issue date:	07/31/2013
From:	Cortopassi L Omaha Public Power District
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
LIC-13-0101 LER 13-005-01
Download: ML13213A069 (6)

LER-2013-005, Regarding Control Room HVAC Modification Not Properly Evaluated

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 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)(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
2852013005R01 - NRC Website

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Omaha Public Power Oislricl 444 South 16 lil Street Mall Omaha, NE 68102-2247 LlC-13-0101 July 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 (L. P. Cortopassi) to NRC (Document Control Desk),

dated April 29, 2013 (LlC-13-0051)

Subject:

Licensee Event Report 2013-005, Revision 1, for the Fort Calhoun Station Please find attached Licensee Event Report 2013-005, Revision 1. This report is being submitted pursuant to 10 CFR 50.73(a)(2)(v)(D) and 10 CFR 50.73(a)(2)(vii)(D). 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.

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

A. T. Howell, NRC Regional Administrator, Region IV J. M. Sebrosky, NRC Senior Project Manager L. E. Wi,lkins, NRC Project Manager J. C. Kirkland, NRC Senior Resident Inspector Employment with Equal Opportunity

NRC FORM 366 (10-2010)

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (10-2010)

LICENSEE EVENT REPORT (LER)

(See reverse for required number of digits/characters for each block)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013

, the NRC may not conduct or sp onsor, and a person is not required to respond to, th e

information collection.

1. FACILITY NAME Fort Calhoun Station

2. DOCKET NUMBER 05000285

3. PAGE 1 OF 5

4. TITLE Control Room HVAC Modification Not Properly Evaluated

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO.

MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 2

27 2013 2013 005 -

1 07 31 2013 FACILITY NAME DOCKET NUMBER 05000

9. OPERATING MODE 5

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)

OTHER 20.2203(a)(2)(vi) 50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)

Specify in Abstract below or in LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET CONCLUSION As previously indicated Condition Report (CR) 2013-04266 questioned the license basis use of probabilistic criteria without prior NRC approval as it relates to the Fort Calhoun Station (FCS) Control Room Air Conditioning System (CRACS) tornado missile protection. To determine the cause of this fault a root cause analysis was conducted. The cause analysis determined that:

In 1995, organizational work practices lacked technical rigor, resulting in FCS personnel incorrectly concluding that a probability methodology for tornado missile protection could be applied to an FCS plant modification via the 50.59 process without obtaining a license amendment.

CORRECTIVE ACTIONS

The control room air conditioners will be provided with missile protection to comply with the stations license, as recently amended, prior to plant heatup. Modifications are in progress to comply with the Amendment No. 272 to the stations license. Additional corrective actions will be administered by the corrective action process.

SAFETY SIGNIFICANCE

A tornado could result in a failure of the CRACS condenser units located on the Auxiliary Building roof.

If this occurs, the control room could become uninhabitable due to excessive temperature. Excessive Control Room Temperatures affect both personnel and equipment. If airborne contamination is present operators would be required to don respiratory equipment, or relocate to the Remote Shutdown Panel.

If the temperature in the control room exceeds 105 degrees (correlating to 120 degrees in internal cabinets) safety related instruments are challenged, affecting the ability to safely shutdown the plant.

Abnormal Operating Procedure (AOP) 13, Loss of Control Room Air Conditioning, provides guidance on mitigating the loss of cooling. In addition, should conditions deteriorate to the point where control room evacuation is required AOP-7, Evacuation of Control Room, will allow the operators to safety shutdown the plant as required.

SAFETY SYSTEM FUNCTIONAL FAILURE This event does result in a safety system functional failure in accordance with NEI-99-02.

PREVIOUS EVENTS There have not been any previous LERs on the potential impact of tornado generated missiles.