05000296/LER-2009-002, Regarding Inoperable High Pressure Coolant Injection System Due to Excessive Water in the Steam Line Drain

Regarding Inoperable High Pressure Coolant Injection System Due to Excessive Water in the Steam Line Drain

ML100141419
Person / Time
Site:	Browns Ferry
Issue date:	01/11/2010
From:	Polson K Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 09-002-00
Download: ML100141419 (13)

LER-2009-002, Regarding Inoperable High Pressure Coolant Injection System Due to Excessive Water in the Steam Line Drain

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
2962009002R00 - NRC Website

text

Tennessee Valley Authority, Post Office Box 2000, Decatur, Alabama 35609-2000 January 11, 2010 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Browns Ferry Nuclear Plant, Unit 3 Facility Operating License No. DPR-68 NRC Docket No. 50-296

Subject:

Licensee Event Report 50-296/2009-002 The enclosed Licensee Event Report (LER) provides details of inoperable High Pressure Coolant Injection System due to excessive water in the steam line drain. The Tennessee Valley Authority is submitting this report in accordance with 10 CFR 50.73(a)(2)(v)(D), as any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident.

There are no new regulatory commitments contained in this letter. Should you have any questions concerning this submittal, please contact F. R. Godwin, Site Licensing and Industry Affairs Manager, at (256) 729-2636.

Respectfully, K. J. Poison Vice President cc: See page 2

U.S. Nuclear Regulatory Commission Page 2 January 11, 2010 Enclosure cc (w/ Enclosure):

NRC Regional Administrator - Region II NRC Senior Resident Inspector - Browns Ferry Nuclear Plant

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 08/31/2010 (9-2007)

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information (See reverse for required number of collection.

AGE Browns Ferry Nuclear Plant Unit 3 05000296 1

of 4

4. TITLE: Inoperable High Pressure Coolant Injection System Due To Excessive Water In The Steam Line Drain

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED I

FACILITY NAME DOCKET NUMBER MONHEAY YERENT-7 IA RE MONTH DAY YEAR N/NA NUMBER NO.

FACILITY NAME DOCKET NUMBER 11 12 2009 2009 -

002 00 01 11 2010 N/A N/A

9. OPERATING MODE

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

[] 20.2201(b)

E] 20.2203(a)(3)(i)

E0 50.73(a)(2)(i)(C)

El 50.73(a)(2)(vii)

El 20.2201(d)

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

El 50.73(a)(2)(ii)(A)

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

E] 20.2203(a)(1)

El 20.2203(a)(4)

El 50.73(a)(2)(ii)(B)

El 50.73(a)(2)(viii)(B)

E] 20.2203(a)(2)(i)

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

El 50.73(a)(2)(iii)

El 50.73(a)(2)(ix)(A)

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

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

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

El 50.73(a)(2)(x)

E] 20.2203(a)(2)(iii)

El 50.36(c)(2)

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

El 73.71(a)(4)

El 20.2203(a)(2)(iv)

[] 50.46(a)(3)(ii)

El 50.73(a)(2)(v)(B)

[1 73.71(a)(5) 100 E] 20.2203(a)(2)(v)

[E 50.73(a)(2)(i)(A)

El 50.73(a)(2)(v)(C)

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

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

ED 50.73(a)(2)(v)(D)

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NRC

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

Steve Austin, Licensing Engineer 256-729-2070MANU-REPORTABLE MANU-REPORTABLE

CAUSE

SYSTEM COMPONENT

CAUSE

SYSTEM COMPONENT FACTURER TO EPIX FACTURER TO EPIX FCUE OEI

14. SUPPLEMENTAL REPORT EXPECTED

15. EXPECTED MONTH DAY YEAR SUBMISSION

[] YES (If yes, complete 15. EXPECTED SUBMISSION DATE)

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

On November 12, 2009, at approximately 1235 hours0.0143 days <br />0.343 hours <br />0.00204 weeks <br />4.699175e-4 months <br /> Central Standard Time (CST), while securing the High Pressure Coolant Injection (HPCI) turbine following the performance of Surveillance Procedure, Unit 3 HPCI Main and Booster Pump Set Developed Head and Flow Rate Test at Rated Reactor Pressure, Browns Ferry Nuclear Plant (BFN) Operations personnel received an alarm indicating high water level in the HPCI turbine exhaust steam drain pot. In accordance with the applicable Alarm Response Procedure, Operations personnel opened the HPCI condensate level control valve, and subsequently dispatched personnel to the HPCI pump to drain the condensate from the drain pot through the drain pot level switch instrument test drain. Operations personnel removed in excess of 80 gallons of condensate from the HPCI turbine exhaust drain pot to clear the alarm. BFN Chemistry personnel analyzed the condensate and determined it was from the suppression pool. At 1711 hours0.0198 days <br />0.475 hours <br />0.00283 weeks <br />6.510355e-4 months <br /> CDT, because Operations personnel could not verify the HPCI system exhaust line was fully drained they declared the HPCI system inoperable. The immediate cause of HPCI inoperability was high water level in the HPCI turbine exhaust drain pot. The root cause for the HPCI system inoperability was siphoning of water from the suppression pool. The siphoning resulted in water flowing back from the suppression pool to the HPCI system drain pot via the HPCI drain pot drain line. TVA is planning to permanently remove the HPCI turbine exhaust drain line from service. Immediate corrective actions included closing and administratively controlling two series valves in the turbine exhaust drain line between the turbine exhaust drain pot and the suppression pool.

NRC FORM 366 (9-2007)

(If more space is required, use additional copies of (If more space is required, use additional copies of (if more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A) (17) pot level switches. In this event, suppression pool water flowed back to the HPCI turbine exhaust drain pot following HPCI system operation.

V. ASSESSMENT OF SAFETY CONSEQUENCES

The safety consequences of this event were not significant. BFN TS 3.5.1, Required Action C.2, allows continued power operation for up to 14 days with the HPCI system inoperable as long as the RCIC system is operable. In this condition, the other required Emergency Core Cooling Systems were operable and remained capable of mitigating design basis accidents and transients assumed in the UFSAR. In addition, the RCIC system was verified operable during this time and would have automatically provided makeup water to the reactor if required, at most reactor operating pressures. Therefore, TVA concludes that there was no significant reduction in the protection of the public by this event.

VI. CORRECTIVE ACTIONS

A.

Immediate Corrective Actions

Immediate corrective actions included closing and administratively controlling two series valves in the turbine exhaust drain line between the turbine exhaust drain pot and the suppression pool. This isolates the suppression pool from the turbine exhaust drain pot. The HPCI turbine was placed in service as a post maintenance test for isolating the suppression pool from the turbine exhaust drain pot. No issues were found with the HPCI system performance during and following the post maintenance testing.

B.

Corrective Actions to Prevent Recurrence - The corrective actions to prevent recurrence are being managed by BFN's corrective action program.

TVA is planning to permanently remove the HPCI turbine exhaust drain line from service.

VII. ADDITIONAL INFORMATION

A.

Failed Components None.

B.

PREVIOUS LERS ON SIMILAR EVENTS None.

C.

Additional Information

Corrective action document for this report is Problem Evaluation Report 207915.

D.

Safety System Functional Failure Consideration:

This event is classified as a safety system functional failure according to NEI 99-02.

E.

Scram With Complications Consideration:

This event was not a complicated scram according to NEI 99-02.

VIII. COMMITMENTS

None.