05000382/LER-2012-004, Regarding Essential Chiller Oil Leak Creates Unanalyzed Past Operability Condition
| ML12174A161 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 06/21/2012 |
| From: | Jacobs D Entergy Nuclear South, Entergy Operations |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| W3F1-2012-0047 LER 12-004-00 | |
| Download: ML12174A161 (2) | |
| 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)(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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3822012004R00 - NRC Website | |
text
10 CFR 50.73 W3F1-2012-0047 June 21, 2012 U.S. Nuclear Regulatory Commission Attn: Document Control Desk 11555 Rockville Pike Rockville, MD 20852
Subject:
Licensee Event Report 2012-004-00 Waterford Steam Electric Station, Unit 3 (Waterford 3)
Docket No. 50-382 License No. NPF-38
Dear Sir or Madam:
Entergy is hereby submitting Licensee Event Report (LER) 2012-004-00 for Waterford Steam Electric Station Unit 3 (Waterford 3). This report provides details associated with an inoperable Essential Chiller.
This report contains no new commitments. Please contact Michael E. Mason, acting Licensing Manager, at (504) 739-6673 if you have questions regarding this information.
Sincerely, DJ/WH
Attachment:
Licensee Event Report 2012-004-00 Entergy Nuclear South Entergy Operations, Inc.
17265 River Road Killona, LA 70057-3093 Tel 504-739-6660 Fax 504-739-6678 djacob2@entergy.com Donna Jacobs Vice President - Operations Waterford 3
W3F1-2012-0047 Page 2 cc:
Regional Administrator, U.S. NRC Region IV RidsRgn4MailCenter@nrc.gov U. S. NRC Project Manager, Waterford 3 Kaly.Kalyanam@nrc.gov NRC Senior Resident Inspector, Waterford 3 Marlone.Davis@nrc.gov INPO Records Center lerevents@inpo.org
Attachment to W3F1-2012-0047 Licensee Event Report 2012-004-00
NRC FORM 366 (10-2010)
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
(See reverse for required number of digits/characters for each block)
APPROVED BY OMB NO. 3150-0104 EXPIRES 10/31/2013
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Waterford 3 Steam Electric Station 05000 382 1 OF 5
- 4. TITLE Essential Chiller Oil Leak Creates Unanalyzed Past Operability Condition
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO MONTH DAY YEAR 05000 FACILITY NAME DOCKET NUMBER 04 22 2012 2012 - 004 - 00 06 21 2012 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 1 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C) 100 20.2203(a)(2)(vi) 50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)
OTHER Specify in Abstract below or in Since the Essential Chillers provide a support function, and the impact of a loss of CHW cooling would have cascaded into other safety systems, a review of Station Log entries was conducted for possible affected safety systems during the period 3/23/2012 through 4/22/2012.
There were several TS entries made during this period. On several occasions the Component Cooling Water System (CCW) [BS] Train B was declared inoperable (TS 3.7.3 entry) to fill the Spent Fuel Pool [DA] from the Condensate Storage Pool (CSP) [KA] using the CCW makeup pump. In addition, TS 3.7.3 was entered to realign CCW Pump B to replace the AB Pump on 4/20/2012 and then conduct operability testing of CCW Pump B. CCW Train B was declared inoperable for valve testing. The CCW pumps are cooled by CHW system air handling units, although the CCW Makeup pumps, which are used for the subject fill evolutions, are located in the common area on the RAB -35 ft. el. and are not cooled by CHW. The CCW Makeup system is required for CCW operability to provide makeup to the CCW system, during and following a design basis event or accident. During each of these planned TS entries, the associated evolution was conducted per established procedures with operators in attendance. The evolutions were conducted promptly and without evident delay, and the evolutions were virtually certain of successful completion.
Other observed TS entries during the period included TS 3.8.2.1 and TS 3.8.3.1, to support the realignment of the 4KV 3AB3 Bus from 3A3 to 3B3. The 3AB3 Bus swap affected the plant electrical distribution system, which includes cable routings through areas cooled by the CHW system. The 4KV Bus swap was conducted promptly, per established procedures, with operator(s) in control during the entire evolution, and the evolution was virtually certain to be completed successfully.
Other Train B or common system/area TS entries observed during the subject period were not impacted by the inoperability of CHW cooling.
Per the review of the Station Logs for the period, there were no failures or degraded conditions of any Train B or common equipment noted that, when combined with the inoperability of the Essential Chiller A, would have resulted in a complete loss of a specified safety function.
The Safety Significance of the identified condition is low, since the CHW Train B cooling function remained available during the subject period from 3/23/2012 through 4/22/2012, and since no interim actions were required during the planned evolutions to reduce the effect on Nuclear Safety.
The apparent cause evaluation found that there were no adverse personnel or radiological safety implications as a result of the identified condition.
A quantitative analysis of Safety Significance was performed by the Safety Analysis group and documented in the site corrective action program. The mission time for the site Probabalistic Risk Analysis (PRA) model, consistent with current industry practice, is set at 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> mission time inherently assumes that, given an initiating event, the plant response is a trip and a safe condition will be reached within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the trip (otherwise, core damage occurs). Based on the site PRA model, a failure of the essential chiller beyond the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> mission time is insignificant and there is no change in core damage frequency (CDF) or large early release frequency (LERF).
SIMILAR EVENTS
Corrective action program data for the past three years was searched for similar failures. None were found.
ADDITIONAL INFORMATION
Energy industry identification system (EIIS) codes are identified in the text within brackets [ ].