05000395/LER-2016-004, Steam Propagation Barrier Degraded Due to Missing Orifices

Steam Propagation Barrier Degraded Due to Missing Orifices

ML16319A401
Person / Time
Site:	Summer
Issue date:	11/14/2016
From:	Lippard G South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 16-004-00
Download: ML16319A401 (5)

LER-2016-004, Steam Propagation Barrier Degraded Due to Missing Orifices

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 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)(A), Seriously Degraded 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)(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)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(x)
3952016004R00 - NRC Website

text

A SCANA COMPANY George A. Lippard Vice President, Nuclear Operations 803.345.4810 November 14, 2016 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555

Dear Sir I Madam:

Subject:

VIRGIL C. SUMMER NUCLEAR STATION (VCSNS), UNIT 1 DOCKET NO. 50-395.

OPERATING LICENSE NO. NPF-12 LICENSEE EVENT REPORT (LER 2016-004-00)

STEAM PROPAGATION BARRIER DEGRADED DUE TO MISSING ORIFICES Attached is Licensee Event Report (LER) 2016-004-00, for the Virgil C. Summer Nuclear Station. This report describes an event that was identified based on an Extent of Condition Review for LER 2016-003-00 Steam Propagation Door (DRIB/1 07)

Discovered Propped Open. The station identified orifices that were not installed in the correct drain lines as specified in a design change package. The station has conducted a preliminary evaluation of the rooms if a High Energy Line Break (HELB) event occurred. This report is submitted in accordance with 1 OCFR50. 73(a)(2)(v)(D) and will be supplemented when results are finalized.

Should you have any questions, please call Mr. Bruce Thompson at (803) 931-5042.

WHKIGAL/rp Attachment c:

K. B. Marsh S. A. Byrne J. B. Archie N.S.Carns J. H. Hamilton S.M. Shealy W. M. Cherry C. Haney Very truly yours,

• ~*

George A. Lippard S. A. Williams NRC Resident Inspector L. W. Harris Paulette Ledbetter J. C. Mellette ICES Coordinator K. M. Sutton INPO Records Center Marsh USA, Inc.

Maintenance Rule Engineer NSRC RTS (CR-16-04716 & CR-16-04801)

File (818. 07)

PRSF (RC-16-0158)

V. C. Summer Nuclear Station

• P. 0. Box 88 *Jenkinsville, SC

• 29065

• F (803) 941-9776

LICENSEE EVENT REPORT (LER)

NRC FORM 366 (06-2016)

U.S. NUCLEAR REGULATORY COMMISSION 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 e-mail to Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and 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 control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (See Page 2 for required number of digits/characters for each block) 1 OF

3. PAGE 05000

4. TITLE

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

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

FACILITY NAME 05000 DOCKET NUMBER FACILITY NAME 05000 DOCKET NUMBER

9. OPERATING MODE

10. POWER LEVEL

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

12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT TELEPHONE NUMBER (Include Area Code) CAUSE SYSTEM COMPONENT MANU-FACTURER REPORTABLE TO EPIX

CAUSE

SYSTEM COMPONENT MANU-FACTURER REPORTABLE TO EPIX

14. SUPPLEMENTAL REPORT EXPECTED YES (If yes, complete 15. EXPECTED SUBMISSION DATE)

NO

15. EXPECTED SUBMISSION DATE YEAR DAY MONTH ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)

NRC FORM 366 (06-2016)

YEAR YEAR DAY MONTH 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(vii) 20.2203(a)(2)(ii) 20.2203(a)(2)(i) 20.2203(a)(1) 20.2201(d) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(2)(v) 20.2203(a)(2)(vi) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1)(i)(A) 50.36(c)(1)(ii)(A) 50.36(c)(2) 50.46(a)(3)(ii) 50.73(a)(2)(i)(A) 50.73(a)(2)(i)(B) 50.73(a)(2)(ii)(A) 50.73(a)(2)(ii)(B) 50.73(a)(2)(iii) 50.73(a)(2)(iv)(A) 50.73(a)(2)(v)(A) 50.73(a)(2)(v)(B) 50.73(a)(2)(v)(C) 50.73(a)(2)(v)(D) 50.73(a)(2)(viii)(A) 50.73(a)(2)(viii)(B) 50.73(a)(2)(ix)(A) 50.73(a)(2)(x) 73.71(a)(4) 73.71(a)(5)

OTHER Specify in Abstract below or in Page of 05000-

3. LER NUMBER YEAR SEQUENTIAL NUMBER REV NO.

TS 3/4.7.9, Area Temperature Monitoring, and associated Table 3.7-7 describe the area temperature limits during normal operation due to cooling provided by the VU System. If the chiller cooling a Chilled Water loop is not running, room temperatures will rise over time. If the temperature in a given area exceeds the limit shown in TS Table 3.7-7 for eight hours, a Special Report detailing the basis for continued operability must be submitted to the NRC within three days. In addition, if the Technical Specifications limit for a given area is exceeded by thirty degrees for four hours, the equipment in the associated area must be declared inoperable.

TS 3/4.7.6, Control Room Emergency Filtration Systems (CREFS), states that two CREFS trains shall be operable. The surveillance requirements under TS 3/4.7.6 require each CREFS train to be demonstrated operable through verification that the control room air temperature is less than or equal to 85 degrees Fahrenheit.

A thermal hydraulic model was developed using the GOTHIC computer code (version 8.1) to calculate the environmental conditions that could have existed at IB 412 foot elevation during a postulated HELB event. The GOTHIC computer program is a general purpose analysis tool that solves the conservation equations for mass, energy, and momentum for multi-component, multi-phase flow, and it has been used extensively for compartment transient analysis in nuclear power plants. The preliminary analysis demonstrates that the event and the postulated effect on the rooms are not expected to experience a significant temperature rise or be at a significant risk of condensation. As a result, for the spectrum of HELB events, which are consistent with the design basis evaluation of steam line breaks outside of containment, there is reasonable assurance that the risk significant equipment in the Mild Area (i.e., Chiller, Chiller Pump, Battery and Battery Charger rooms) would have been able to perform their required functions had such an event occurred.

The station is currently evaluating breaks smaller than the design basis break sizes. This LER will be supplemented when results are finalized.

3.0 SAFETY SIGNIFICANCE

The safety significance of this event will be provided in a supplemental report to this LER.

4.0 PREVIOUS OCCURRENCE No previous occurrence within the last three years.

5.0 CORRECTIVE ACTIONS

Immediate action taken: On September 14, 2016, stopped all associated VU chiller work and ensured all steam propagation doors were closed. Station Order 16-05 was issued that directs that no work can be performed in the chiller rooms that would require the door(s) to be propped open. The Station Order was in place until the orifice installations in the sumps was corrected.

4 4

VC SUMMER - UNIT 1 395 2016 004 00