05000410/LER-2014-005, Regarding Secondary Containment Inoperable Due to Sustained High Winds

Regarding Secondary Containment Inoperable Due to Sustained High Winds

ML14141A537
Person / Time
Site:	Nine Mile Point
Issue date:	05/09/2014
From:	John Stanley Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 14-005-00
Download: ML14141A537 (7)

LER-2014-005, Regarding Secondary Containment Inoperable Due to Sustained High Winds

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
4102014005R00 - NRC Website

text

A Exelon Generation, Jim Stanley Plant Manager - Nine Mile Point P.O. Box 63 Lycoming, NY 13093 315 349 5205 Office www.exeloncorp.com James.stanley@exeloncorp.com May 9, 2014 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTENTION: Document Control Desk

SUBJECT:

Nine Mile Point Nuclear Station, Unit 2 Renewed Facility Operating License No. NPF-69 Docket No. 50-410 Licensee Event Report 2014-005, Secondary Containment Inoperable Due to Sustained High Winds In accordance with 10 CFR 50.73(a)(2)(v)(C), please find attached Licensee Event Report 2014-005, Secondary Containment Inoperable Due to Sustained High Winds.

There are no regulatory commitments in this submittal.

Should you have questions regarding the information in this submittal, please contact Everett (Chip)

Perkins, Director Licensing, at (315) 349-5219.

Sincerely, JJS/KP

Attachment:

Licensee Event Report 2014-005, Secondary Containment Inoperable Due to Sustained High Winds cc:

NRC Project Manager NRC Resident Inspector NRC Regional Administrator td&(L

ATTACHMENT LICENSEE EVENT REPORT 2014-005 SECONDARY CONTAINMENT INOPERABLE DUE TO SUSTAINED HIGH WINDS Nine Mile Point Nuclear Station, LLC May 9, 2014

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0113112017 (02-2014)

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 industry.

Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by S LICENSEE EVENT REPORT (LER) internet e-mail to Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and (See Page 2 for required number of Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB digits/characters for each block) control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

3. PAGE Nine Mile Point Unit 2 05000410 1 OF 5

4. TITLE Secondary Containment Inoperable Due to Sustained High Winds

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MNH DY YA YER SEQUENTIAL REV MOT A

ER FACILITY NAME DOCKET NUMBER YEAR NUMBER NO.

MONTH DAY YEAR N/A N/A FACILITY NAME DOCKET NUMBER 3

12 2014 2014 005

- 00 5

9 2014 N/A N/A

9. OPERATING MODE

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

LI 20.2201(b)

LI 20.2203(a)(3)(i)

EL 50.73(a)(2)(i)(C)

LI 50.73(a)(2)(vii)

[1 20.2201(d)

L] 20.2203(a)(3)(ii) 0I 50.73(a)(2)(ii)(A)

El 50.73(a)(2)(viii)(A)

LI 20.2203(a)(1)

El 20.2203(a)(4)

[:1 50.73(a)(2)(ii)(B)

LI 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i)

El 50.36(c)(1)(i)(A)

[LI 50.73(a)(2)(iii)

LI 50.73(a)(2)(ix)(A)

10. POWER LEVEL

[] 20.2203(a)(2)(ii)

El 50.36(c)(1)(ii)(A)

[L 50.73(a)(2)(iv)(A)

El 50.73(a)(2)(x)

LI 20.2203(a)(2)(iii)

[1 50.36(c)(2)

[]

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

[] 73.71(a)(4)

L] 20.2203(a)(2)(iv)

El 50.46(a)(3)(ii)

[] 50.73(a)(2)(v)(B)

[] 73.71(a)(5) 15 El 20.2203(a)(2)(v)

El 50.73(a)(2)(i)(A)

E 50.73(a)(2)(v)(C)

LI OTHER LI 20.2203(a)(2)(vi)

Eli 50.73(a)(2)(i)(B)

LI 50.73(a)(2)(v)(D)

Specify in Abstract below or in E_______

2.23a()v)5.3a2()B

D. DATES AND APPROXIMATE TIMES OF MAJOR OCCURRENCES

The dates, times and major occurrences for this event are as follows:

March 12 1410:

Declared Division 2 GTS inoperable for dP control, placed 2GTS*PV5B in manual.

1422:

Entered TS 3.6.4.1, Condition A to restore secondary containment.

Entered N2-EOP-SC due to secondary containment pressure being positive.

Station announcement made on EOP entry including direction to ensure all air locked doors are shut.

1526:

Declared Division 2 GTS operable. PER USAR 6.5.1.5 with 2GTS*PV5B isolated Division 2 GTS is operable.

1630:

Isolated the secondary containment to support maintaining negative dP.

Entered ODCM D.3.3.2, Conditions D and F (Reactor Building Vent Radiation Monitor) 1700:

Exited TS 3.6.4.1, Condition A. Secondary containment dP maintained greater than 0.25 inches vacuum water gauge.

E. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED

No other systems or secondary functions were affected beyond the systems discussed in Section I.B.

F. METHOD OF DISCOVERY

This condition was recognized by Operations as they monitored secondary containment dP during the wind storm.

G. MAJOR OPERATOR ACTION:

Operations placed the GTS in manual to maximize negative differential pressure. TS 3.6.4.1, Condition A was entered due to the inability to maintain the required dP. The reactor building was isolated to support maintaining the dP as negative. Service water valves were throttled to control secondary containment temperature due to its isolation. The dP subsequently returned to greater than 0.25 inches vacuum water gauge.

H. SAFETY SYSTEM RESPONSES:

This event was caused by high winds from Winter Storm Vulcan. The Secondary Containment ventilation and the GTS equipment performed as expected.

II. CAUSE OF EVENT

The positive dP was related to sustained high winds from the northeast associated with Winter Storm Vulcan.

III. ANALYSIS OF THE EVENT

The event described in this LER is reportable under 10 CFR 50.72 (b)(3)(v)(C) and 10 CFR 50.73(a)(2)(v)(C) as any event or 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. In addition, isolation of the reactor building vent radiation monitor which occurred during the event is reportable under 10 CFR 50.72 (b)(3)(xiii) and represented a loss of emergency assessment capability.

The event of the secondary containment dP dropping below the required TS minimum value is attributed to outdoor environmental conditions, specifically high winds associated with a winter storm. Operator actions taken on March 12, 2014 to address the high wind conditions and increasing secondary containment pressure were based on monitoring available meteorological data and were consistent with plant procedures. Procedure N2-OP-52 provides operators with direction to place the GTS in service and/or isolate the Reactor Building to maintain a negative pressure in the secondary containment. The causal evaluation of this event identified that N2-OP-52 does not provide this direction prior to exceeding the TS limit for secondary containment dP. This lack of procedural direction was identified as the apparent cause of this event.

The required TS Limiting Condition for Operation (LCO) action statement during this event was entered and subsequently exited once the secondary containment dP was restored to above the required TS minimum value. In all cases, the TS required completion time was not exceeded. The secondary containment structural integrity, the ability to automatically isolate the non-safety related Reactor Building Ventilation System, and the GTS availability were not impacted. Secondary containment would have continued to perform its intended safety function.

Based on the above discussion, it is concluded that the safety significance of this event is low and the event did not pose a threat to the health and safety of the public or plant personnel.

This event does not affect the NRC Regulatory Oversight Process Indicators.

IV. CORRECTIVE ACTIONS

A. ACTION TAKEN TO RETURN AFFECTED SYSTEMS TO PRE-EVENT NORMAL STATUS:

Operations entered the action statement for TS 3.6.4.1, Condition A and associated plant procedures to return the affected systems to pre-event status. These steps combined with placing the GTS in operation returned the secondary containment to pre-event status.

B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE:

The corrective action planned involves revising N2-OP-52 to provide direction to initiate GTS and isolate the reactor building during high wind conditions prior to exceeding TS limit for secondary containment dP.

V. ADDITIONAL INFORMATION

A. FAILED COMPONENTS:

There were no failed components that contributed to this event.

B. PREVIOUS LERs ON SIMILAR EVENTS:

LER 2013-005 identified that NMP2 did not report past reportable conditions in which the secondary containment dP drop below the TS minimum value. The LER noted this plant condition has occurred numerous times in the past when the secondary containment has been declared inoperable as a result of the secondary containment dP dropping below the required TS minimum of negative 0.25 inches water gauge. The direct causes of the secondary containment dP dropping below the required TS minimum value have been attributed to changes in outdoor environmental conditions (changing wind direction and velocity), changing of lineups or equipment failures associated with the normal non-safety related Reactor Building Ventilation System. In each case, the required TS Limiting Condition for Operation (LCO) action statement was entered and subsequently exited once the secondary containment dP was restored to above the required TS minimum value. In all cases the TS required completion time was not exceeded.

C. THE ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) COMPONENT FUNCTION IDENTIFIER AND SYSTEM NAME OF EACH COMPONENT OR SYSTEM REFERRED TO IN THIS LER:

IEEE 803 FUNCTION IEEE 805 SYSTEM COMPONENT IDENTIFIER IDENTIFICATION Reactor Building (BWR)

N/A NG Reactor Building Ventilation System PDIC VA Standby Gas Treatment System N/A BH Reactor Building Vent Radiation Monitoring System MON IL D. SPECIAL COMMENTS:

None