05000336/LER-2014-005, Regarding Train a Containment Spray Inoperable Due to Gas Voids

Regarding Train a Containment Spray Inoperable Due to Gas Voids

ML14203A049
Person / Time
Site:	Millstone
Issue date:	07/16/2014
From:	Adams M Dominion, Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
14-331 LER 14-005-00
Download: ML14203A049 (6)

LER-2014-005, Regarding Train a Containment Spray Inoperable Due to Gas Voids

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 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
3362014005R00 - NRC Website

text

'Dominion Dominion Nuclear Connecticut, Inc.

Rope Ferry Rd., Warerford, CT 06385

'Mailing Address: VO. Box 128

\\Vaterford, CT 06385 dora.com JUL 1 6 2014 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.

MPS Lic/LES Docket No.

License No.14-331 RO 50-336 DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 LICENSEE EVENT REPORT 2014-005-00 TRAIN A CONTAINMENT SPRAY INOPERABLE DUE TO GAS VOIDS This letter forwards Licensee Event Report (LER) 2014-005-00 documenting a condition discovered at Millstone Power Station Unit 2 on May 17, 2014. This LER is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(B) as any operation or condition which was prohibited by the plant's technical specifications.

If you have any questions or require additional information, please contact Mr. William D. Bartron at (860) 444-4301.

Sincerely, Matt Adams Plant Manager - Millstone Attachments: 1 Commitments made in this letter: None AJ

Serial No.14-331 Docket No. 50-336 Licensee Event Report 2014-005-00 Page 2 of 2 cc:

U.S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd, Suite 100 King of Prussia, PA 19406-2713 M. C Thadani Sr. Project Manager - Millstone Power Station U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 08 B1 Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.14-331 Docket No. 50-336 Licensee Event Report 2014-005-00 ATTACHMENT LICENSEE EVENT REPORT 2014-005-00 TRAIN A CONTAINMENT SPRAY INOPERABLE DUE TO GAS VOIDS MILLSTONE POWER STATION UNIT 2 DOMINION NUCLEAR CONNECTICUT, INC.

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 01/31/2017 (02-2014)

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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.

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,Send comments regarding burden estimate to the FOIA, Privacy and Information Collections

.. IE EV NT RBranch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by LICENSEE EVENTi 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 sfor each block) 20503. It a means used to impose an information collection does not display a currently valid OMB digits/characters fcontrol number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

3. PAGE Millstone Power Station-Unit 2 05000336 1 OF 3

4. TITLE Train "A" Containment Spray Inoperable Due to Gas Voids

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MNH DY YA YER SQETA RE MOT DA YER FACILITY NAME DOCKET NUMBER YEAR NUMBER NO.

DAY YEAR 05000 FACILITY NAME DOCKET NUMBER

- 2014 005 00 07 16 2014 05000

9. OPERATING MODE

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

[1 20.2201(b)

LI 20.2203(a)(3)(i)

LI 50.73(a)(2)(i)(C)

LI 50.73(a)(2)(vii) 3 F 20.2201(d)

E] 20.2203(a)(3)(ii)

LI 50.73(a)(2)(ii)(A)

LI 50.73(a)(2)(viii)(A) 3 El 20.2203(a)(1)

LI 20.2203(a)(4)

LI 50.73(a)(2)(ii)(B)

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

[]

20.2203(a)(2)(i)

LI 50.36(c)(1)(i)(A)

[1 50.73(a)(2)(iii)

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

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

[1 50.36(c)(1)(ii)(A)

LI 50.73(a)(2)(iv)(A)

L] 50.73(a)(2)(x)

LI 20.2203(a)(2)(iii)

LI 50.36(c)(2)

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

LI 73.71(a)(4)

LI 20.2203(a)(2)(iv)

LI 50.46(a)(3)(ii)

[1 50.73(a)(2)(v)(B)

LI 73.71(a)(5) 000 00 20.2203(a)(2)(v)

L] 50.73(a)(2)(i)(A)

LI 50.73(a)(2)(v)(C)

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

[

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

[]

50.73(a)(2)(v)(D) specifyin Abstrmct heloworin

_____________________________________________________________________________NRC___FoNRCForm66A

12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT TELEPHONE NUMBER (Include Area Code)

William D. Bartron, Supervisor Nuclear Station Licensing 1 860-444-4301CSYTM CMOET MANU-REPORTABLE CAS SYTE MA EPRAL CPE FACTURER TO EPIX

CAUSE

SY COMPONENT FACTURER TO EPIX

14. SUPPLEMENTAL REPORT EXPECTED

15. EXPECTED MONTH DAY I

YEAR SUBMISSION LI YES (If yes, complete 15. EXPECTED SUBMISSION DATE)

Z NO DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)

At 1933 on May 16, 2014 while in MODE 3, Millstone Power Station Unit 2 (MPS2) exceeded the Limiting Condition for Operation (LCO) of plant Technical Specification (TS) 3.6.2.1 'Containment Spray System' Action a.1 for an inoperable containment spray pump. The 'A' containment spray (CS) pump was declared inoperable at 0018 on May 17, 2014, the date of discovery, following completion of surveillance testing to determine the presence of gas voids.

However, the gas was introduced earlier during the refueling outage and the TS LCO went into effect upon first entry into MODE 3 greater than 1750 psia on May 13, 2014, at 1933. TS 3.6.2.1 Action a.1 requires that the pump be restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduce pressurizer pressure to less than 1750 psia within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. MPS2 had been in a MODE where the CS system was required to be OPERABLE for 70.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> prior to completion of the testing. The gases were successfully removed by venting and the system was restored to OPERABLE status at 1221 on May 17, 2014.

This condition is being reported as any operation or condition which was prohibited by the plant's technical specifications in accordance with 10 CFR 50.73 (a)(2)(i)(B). The condition was caused by not adequately venting the CS system and delays in communicating the surveillance results, combined with a need to schedule performance of the surveillance testing earlier in a refueling outage. Corrective actions planned will improve scheduling of the testing and will result in more timely communications of the results from completed testing.

NRC FORM 366 (02-2014)

1. EVENT DESCRIPTION

At 1933 on May 16, 2014 while in MODE 3, Millstone Power Station Unit 2 (MPS2) exceeded the Limiting Condition for Operation (LCO) of plant Technical Specification (TS) 3.6.2.1 "Containment Spray System" Action a.1 for an inoperable containment spray pump. The 'A' containment spray (CS) pump was declared inoperable at 0018 on May 17, 2014, the date of discovery, following completion of surveillance testing to determine the presence of gas voids. However, the gas found was introduced earlier during the refueling outage. The TS LCO went into effect upon entry into MODE 3 greater than 1750 psia on May 13, 2014, at 1933. TS 3.6.2.1 Action a.1 requires that the pump be restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduce pressurizer pressure to less than 1750 psia within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

MPS2 had been in a MODE where the CS system was required to be OPERABLE for approximately 70.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> prior to completion of the testing. The gases were successfully removed by venting and the system was restored to OPERABLE status at 1221 on May 17, 2014, 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> after entering an applicable MODE for TS 3.6.2.1.

This condition is being reported as any operation or condition which was prohibited by the plant's technical specifications in accordance with 10 CFR 50.73 (a)(2)(i)(B).

2.

CAUSE

Exceeding the LCO time limit while removing gases was due to not adequately venting the CS system following maintenance performed during the outage and delays in communicating the surveillance results to Operations, combined with a need to schedule performance of the surveillance testing earlier in a refueling outage.

3.

ASSESSMENT OF SAFETY CONSEQUENCES

The containment spray (CS) system is composed of two redundant independent trains. The CS system in conjunction with the containment air recirculation and cooling system provides sufficient heat removal capability to limit the post-accident containment pressure and structural temperature below the design values.

The safety consequences of this condition was determined to be low. The "A" Train of the CS system was considered to be unavailable because the amount of gas found during the ultrasonic testing exceeded engineering guidance for system operability. The "B" Train of the CS system was confirmed to be free of voids, and remained available to perform the safety function, if needed. In addition, both trains of containment air recirculation and cooling systems were available during the period to perform the safety function, if necessary. The period of unavailability of the "A" Train of the containment spray system was of short duration, approximately 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br />, and occurred during MODE 3, while the plant was shutdown.

4.

CORRECTIVE ACTION

Corrective actions planned will improve scheduling of system testing for gas voids after outages, and will result in more timely communications of the results from completed testing to Operations.

4.

CORRECTIVE ACTION (Continued)

Additional corrective actions are being taken in accordance with the station's corrective action program.

5.

PREVIOUS OCCURRENCES

There have been no previous occurrences.

6. Energy Industry Identification System (EIIS) codes Containment Spray System - BE Pump-P