05000388/LER-2011-004, Regarding Unit 2 HPCI Inoperability

Regarding Unit 2 HPCI Inoperability

ML113390128
Person / Time
Site:	Susquehanna
Issue date:	12/05/2011
From:	Kearney F Susquehanna
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
PLA-6790 LER 11-004-00
Download: ML113390128 (4)

LER-2011-004, Regarding Unit 2 HPCI Inoperability

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 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)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3882011004R00 - NRC Website

text

Faber A. Kearney Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Stop OP1-17 Washington, DC 20555 PPL Susquehanna, LLC 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 fakearney@pplweb.com SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-388/2011-004-00 LICENSE NO. NPF -22 PLA-6790 Docket No. 50-388 Attached is Licensee Event Report (LER) 50-388/2011-004-00. The event involved fluctuations in the Unit 2 High Pressure Coolant Injection System (HPCI) electronic governor that resulted in Unit 2 HPCI being declared inoperable. This event was determined to be reportable under 10CFR50.73(a)(2)(v)(D) as a condition that could have prevented the fulfillment of a safety function.

There were no actual consequences to the health and safety of the public as a result of this event.

No regulatory commitments are associated with this LER.

Sincerely, Attachment Copy:

NRC Region I Mr. P. W. Finney, NRC Sr. Resident Inspector Mr. R. R. Janati, DEP/BRP Mr. B. K. Vaidya, NRC Project Manager

NRCFORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:10/31/2013 (10-2010)

, the NRC digits/characters for each block) may not conduct or sponsor, and a person is not required to respond to, the information collection.

13. PAGE Susquehanna Steam Electric Station Unit 2 05000388 1 OF 3

4. TITLE Unit 2 HPCI lnoperability

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

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

MONTH DAY YEAR 05000

//)..

0~

FACILITY NAME DOCKET NUMBER 10 06 2011 2011 - 004 -

00

~D/1 05000

9. OPERATING MODE

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

D 20.2201 (b)

D 20.2203(a)(3)(i) 0 50. 73(a)(2)(i)(C)

D 50.73(a)(2)(vii) 1 D 20.2201 (d)

D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A)

D 20.2203(a)(1)

D 20.2203(a)(4)

D 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B)

D 20.2203(a)(2)(i)

D 50.36(c)(1)(i)(A)

D 50.73(a)(2)(iii)

D 50.73(a)(2)(ix)(A)

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

D 50.36(c)(1)(ii)(A)

D 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x)

D 20.2203(a)(2)(iii)

D 50.36(c)(2)

D 50. 73(a)(2)(v)(A)

D 73.71(a)(4) 98.6%

D 20.2203(a)(2)(iv)

D 50.46(a)(3)(ii)

D 50.73(a)(2)(v)(B)

D 73.71(a)(5)

D 20.2203(a)(2)(v)

D 50. 73(a)(2)(i)(A)

D 50.73(a)(2)(v)(C) 0 OTHER D 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B) 181 50. 73(a)(2)(v)(D)

Specify in Abstract below or in

CORRECTIVE ACTIONS

The following corrective actions have been completed:

I REVISION NUMBER 00

3. PAGE 30F3 The Overspeed Test Controller was replaced and the HPCI governor control system calibration was completed.

Shiftly monitoring of the Unit 1 and Unit 2 HPCI and Reactor Core Isolation Cooling system (RCIC)

Electronic Governor Module (EG-M) and ramp generator and signal converter (RGSC) output trend graphs was instituted.

Independent failure analysis of the suspect overspeed test controller was conducted.

The following corrective actions are planned:

Validate and correct as necessary component criticality codes for all Unit 1, Unit 2, and common criticality 5 and 6 components in safety related systems.

Perform a 25% sampling of Unit 1, Unit 2, and common criticality 3 and 4 components in safety related systems to validate and correct as necessary the component criticality codes. If more than 10 components in the initial sample are identified as being coded improperly, 100% of the population will be reviewed.

Periodic exercise of the Unit 1 and Unit 2 overspeed test controller test switches. [Note: the Unit 1 and Unit 2 RCIC systems do not have an overspeed test controller subcomponent.

Evaluate the feasibility of removing the overspeed test controller from the Unit 1 and Unit 2 HPCI governor control circuits.

Revise department procedures to consider the failure mode (electrical contacts in a low voltage circuit experienced a resistance increase over time} when classifying the criticality of new components added to the plant.

No regulatory commitments are associated with this report.

ADDITIONAL INFORMATION

Failed Component Information:

Component:

SY-25681 Toggle Switch Model:

7674K5 Manufacturer: Cutler Hammer.

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None NRC Form 366 (10-2010)