05000461/LER-2013-004, Regarding Loss of Emergency Diesel Room Ventilation Due to Damper Hydramotor Failure

Regarding Loss of Emergency Diesel Room Ventilation Due to Damper Hydramotor Failure

ML13304A502
Person / Time
Site:	Clinton  (NPF-062)
Issue date:	10/11/2013
From:	Taber B Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
SRRS 5A.108, U-604140 LER 13-004-00
Download: ML13304A502 (5)

LER-2013-004, Regarding Loss of Emergency Diesel Room Ventilation Due to Damper Hydramotor Failure

Event date:
Report date:
Reporting criterion:	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)(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 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
4612013004R00 - NRC Website

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,E Exelon Generation, Clinton Power Station 8401 Power Road Clinton, IL 61727 U-604140 October 11, -2013 10 CFR 50.73 SRRS 5A.108 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRC Docket No. 50-461

Subject:

Licensee Event Report 2013-004-00 Enclosed is Licensee Event Report (LER) No. 2013-004-00: Loss of Emergency Diesel Room Ventilation Due to Damper Hydramotor Failure. This report is being submitted in accordance with the requirements of 10 CFR 50.73.

There are no regulatory commitments contained in this report.

Should you have any questions concerning this report, please contact Ms. Kathy Ann Baker, Regulatory Assurance Manager, at (217)-937-2800.

Respectfully, B. Keith Taber Site Vice President Clinton Power Station RSF/blf

Enclosure:

Licensee Event Report 2013-004-00 cc:

Regional Administrator - NRC Region III NRC Senior Resident Inspector - Clinton Power Station Office of Nuclear Facility Safety - IEMA Division of Nuclear Safety

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 (10-2010)

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

3. PAGE Clinton Power Station, Unit 1 05000461 1 OF 4

4. TITLE Loss of Emergency Diesel Room Ventilation Due to Damper Hydramotor Failure

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED T

FACILITY NAME DOCKET NUMBER MONTH DAY Y

YEAR SEQUENTIAL REV MONTH DAY YEAR 05000 FACILITY NAME DOCKET NUMBER 08 15 2013 2013 004 00 10 11 2013 05000

9. OPERATING MODE

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

[1 20.2201(b)

[l 20.2203(a)(3)(i)

El 50.73(a)(2)(i)(C)

[I 50.73(a)(2)(vii) 10 20.2201(d)

El 20.2203(a)(3)(ii)

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

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

El 20.2203(a)(1)

El 20.2203(a)(4)

[I 50.73(a)(2)(ii)(B)

[E 50.73(a)(2)(viii)(B)

[] 20.2203(a)(2)(i)

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

[I 50.73(a)(2)(iii)

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

10. POWER LEVEL 0 20.2203(a)(2)(ii) 0l 50.36(c)(1)(ii)(A)

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

El 50.73(a)(2)(x)

El 20.2203(a)(2)(iii)

El 50.36(c)(2)

[I 50,73(a)(2)(v)(A)

El 73.71(a)(4) 092 El 20.2203(a)(2)(iv)

El 50.46(a)(3)(ii)

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

El 73.71(a)(5)

El 20.2203(a)(2)(v)

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

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

[E OTHER El 20.2203(a)(2)(vi) 0l 50.73(a)(2)(i)(B)

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

Specify in Abstract below or in

C. CAUSE OF EVENT

Based on review of the hydramotor maintenance history and failure analysis from the vendor, the apparent cause of the supply air damper failure to open was that the damper hydramotor experienced an end-of-life failure due to being installed beyond its recommended service life. The hydramotor failed as result of normal age-related degradation of the internal hydraulic pump [P]. The hydramotor had been installed for about 26 years and the recommended service life is 10 years.

The hydramotor was never replaced due to a significant change in hydramotor preventive maintenance (PM) scope in 2005 which should have treated the change as a first-time PM and revised the due date accordingly.

However, the change to the PM retained the original scheduling date and allowed the hydramotor to remain in the system beyond the recommended service life.

D. SAFETY CONSEQUENCES

This event had no actual consequences. The Division 3 EDG was in its normal standby lineup at the time of this event. A failure of the supply air damper to open limits the amount of outside air that can be introduced into the EDG engine and fuel storage rooms to maintain room temperature and remove heat loading from the EDG operation. If an event occurred requiring the Division 3 EDG to run at full load, the EDG could have exceeded the analyzed heat load for the Division 3 EDG room prior to completion of the system's mission time. During this event, the recirculation damper was open and allowing recirculation air flow; therefore, some cooling and heat removal was occurring. Additionally, there is some inlet airflow due to seal leakage around the damper blades and door seals in the fan room, but the amount of cooling this may provide is unknown.

Prior to the event, on 8/14/13, the Division 3 EDG was satisfactorily started for Technical Specification surveillance testing at 0924 hours0.0107 days <br />0.257 hours <br />0.00153 weeks <br />3.51582e-4 months <br /> and run for approximately two hours without any evidence of damper failures and no unexpected room temperature or pressure conditions noted.

At the time of this event the Reactor Core Isolation Cooling System [BN] was operable and all Emergency Core Cooling Systems (with the exception of HPCS) were operable as well as AC power, including Divisions 1 and 2 EDGs. Although HPCS was declared inoperable, HPCS was available with offsite power.

E. CORRECTIVE ACTIONS

The failed hydramotor was replaced, post maintenance testing was completed and functionality/operability was restored on. 8/17/13.

An evaluation determined that critical, non-EQ hydramotors have the correct 10-year frequency PM established. (EQ hydramotors have established PM strategies based on their EQ analyses and are not affected by the cause of this event.)

Ten additional hydramotors have been identified as being installed beyond the 10-year recommended life and will be replaced.

Applicable Engineering and Work Management staff will receive a tailgate on the failure to treat the significant change in PM scope as a new PM task.

F.

PREVIOUS OCCURRENCES

A review for previous occurrences did not identify similar events at Clinton Power Station.

G. COMPONENT FAILURE DATA

Component Description: Modulating Air Damper Hydramotor/Actuator Manufacturer: ITT General Controls Model: NH91