05000336/LER-2014-001, Regarding Completion of Plant Shutdown Required by Technical Specifications

Regarding Completion of Plant Shutdown Required by Technical Specifications

ML14097A016
Person / Time
Site:	Millstone
Issue date:	03/31/2014
From:	Scace S Dominion, Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
14-143 LER 14-001-00
Download: ML14097A016 (6)

LER-2014-001, Regarding Completion of Plant Shutdown Required by Technical Specifications

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 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) 10 CFR 50.73(a)(2)(viii) 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3362014001R00 - NRC Website

text

4Domi nioni Dominion Nuclear Connecticut, Inc.

Rope Ferry Rd., Waterford, CT 06385 Mailing Address: P.O. Box 128 Waterford, CT 06385 dora.corn MAR 3 12014 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.

MPS Lic/GJC Docket No.

License No.14-143 RO 50-336 DPR-65 DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2 LICENSEE EVENT REPORT 2014-001-00 COMPLETION OF PLANT SHUTDOWN REQUIRED BY TECHNICAL SPECIFICATIONS This letter forwards Licensee Event Report (LER) 2014-001-00 documenting an event at Millstone Power Station Unit 2 on January 31, 2014. This LER is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(A).

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

Sincerely,

/Steph 4 E. Scac~e Site Vice President - Millstone Attachments: 1 Commitments made in this letter: None

Serial No.14-143 Docket No. 50-336 Licensee Event Report 2014-001 -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 NRC Project Manager Millstone Units 2 and 3 U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 B-1 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.14-143 Docket No. 50-336 Licensee Event Report 2014-001 -00 ATTACHMENT LICENSEE EVENT REPORT 2014-001-00 COMPLETION OF PLANT SHUTDOWN REQUIRED BY TECHNICAL SPECIFICATIONS 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 102-20141

,,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 intemet 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 Millstone Power Station Unit 2 05000336 1 OF 3

4. TITLE Completion of Plant Shutdown Required By Technical Specifications

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR 05000 NUMBER NO.

FACILITY NAME DOCKET NUMBER 01 31 2014 2014-001 00 03 31 2014 05000

9. OPERATING MODE

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

E 20.2201(b)

El 20.2203(a)(3)(i)

Z 50.73(a)(2)(i)(C)

E 50.73(a)(2)(vii) 3 20.2201(d)

E 20.2203(a)(3)(ii)

L 50.73(a)(2)(ii)(A)

E 50.73(a)(2)(viii)(A)

[] 20.2203(a)(1)

[]

20.2203(a)(4)

[]

50.73(a)(2)(ii)(g)

[]

50.73(a)(2)(viii)(a)

D 20.2203(a)(2)(i)

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

LI 50.73(a)(2)(iii)

E 50.73(a)(2)(ix)(A)

10. POWER LEVEL

[

20.2203(a)(2)(ii)

LI 50.36(c)(1)(ii)(A)

El 50.73(a)(2)(iv)(A)

LI 50.73(a)(2)(x)

LI 20.2203(a)(2)(iii)

LI 50.36(c)(2)

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

El 73.71(a)(4) 00 20.2203(a)(2)(iv)

LI 50.46(a)(3)(ii)

E 50.73(a)(2)(v)(B)

LI 73.71(a)(5) 0L 20.2203(a)(2)(v)

[

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

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

OTHER El 20.2203(a)(2)(vi)

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

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

Specify in Abstract below or in

1. EVENT DESCRIPTION

On January 30, 2014 at 2313, with Millstone Power Station Unit 2 (MPS2) in MODE 1 and at 100%

reactor power, the circuit breaker for the group 1 pressurizer proportional heaters tripped. With the

'B' emergency diesel generator (EDG) out of service for its maintenance outage and therefore inoperable, Technical Specification Action Statement (TSAS) 3.4.4 action b was entered. TSAS 3.4.4 action b requires MPS2 be in at least HOT STANDBY (MODE 3) with the reactor trip breakers open within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN (MODE 4) within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, unless one group of proportional heaters is restored to operable status. MPS2 completed the shutdown to MODE 3 at 0457 and restored the group 1 proportional heaters to operable status at 0747 on January 31, 2014. The initiation of the shutdown was reported to the NRC (event number 49779) pursuant to 10 CFR 50.72(b)(2)(i) - The initiation of any nuclear plant shutdown required by the plant's technical specifications.

This condition is being reported pursuant to 10 CFR 50.73(a)(2)(i)(A) - The completion of any nuclear plant shutdown required by the plant's technical specifications.

Background Information

The pressurizer heaters are single unit, direct immersion heaters which protrude vertically into the pressurizer through sleeves welded in the lower head. Each heater is internally restrained from high amplitude vibrations and can be individually removed for maintenance during plant shutdown.

Approximately 20 percent of the heaters are connected to proportional controllers which adjust the heat input as required to account for steady state losses and to maintain the desired steam pressure in the pressurizer. These heaters are separated into two banks (approximately 160 kW each) and are provided with diverse vital power.

The pressurizer TS limiting condition for operation 3.4.4 states:

The pressurizer shall be OPERABLE with:

a. Pressurizer water level < 70%, and b. At least two groups of pressurizer heaters each having a capacity of at least 130 kW, APPLICABILITY: MODES 1, 2 and 3.

ACTION:

a. With only one group of pressurizer heaters OPERABLE, restore at least two groups 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 in HOT SHUTDOWN within the following 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

b. With the pressurizer otherwise inoperable, be in at least HOT STANDBY with the reactor trip breakers open within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

2. CAUSE

The direct cause of the need to shutdown the unit was the failure of the group 1 proportional pressurizer heaters concurrent with the 'B' EDG being out of service for planned maintenance.

3. ASSESSMENT OF SAFETY CONSEQUENCES

Reactor Coolant system (RCS) pressure control is maintained by pressurizer heaters and the pressurizer spray system. Although the 'B' EDG was out service for planned maintenance, MPS2 was in a normal electrical configuration, therefore one bank of proportional pressurizer heaters was functional (i.e., powered from the offsite power system). Additionally, the pressurizer spray system was not affected, therefore RCS pressure control was always functional. There was no indication of any primary to secondary leakage. There was no release of radioactive material. All safety related systems performed as designed.

4. CORRECTIVE ACTION

Troubleshooting activities determined one of the group 1 proportional heaters (P1-B1) had failed.

The P1 -B1 heater leads were subsequently lifted to remove the failed heater from service.

Following this maintenance activity, a pressurizer heater capacity test was performed and verified the group 1 proportional heaters had a capacity of at least 130KW as required by TS 3.4.4 b. The group 1 proportional heaters and the pressurizer were declared operable and MPS2 was subsequently returned to service. Additional corrective actions are being taken in accordance with the station's corrective action program.

5. PREVIOUS OCCURRENCES

None

6. Energy Industry Identification System (EIIS) codes Electric Resistance Heater - EHTR Pressurizer - PZR Reactor Coolant System - AB Emergency Diesel Generator - DG Door-DR