05000498/LER-2006-002, Regarding Simultaneous Inoperability of Two Essential Chilled Water Trains
| ML061570380 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 05/30/2006 |
| From: | Halpin E South Texas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NOC-AE-06002025 LER 06-002-00 | |
| Download: ML061570380 (10) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 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 |
| 4982006002R00 - NRC Website | |
text
Nuclear Operating Company South Texs Projet Ekc Generting Stion PO. Bar 289 Hf*or, Texas 77483 May 30, 2006 NOC-AE-06002025 10CFR50.73 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 South Texas Project Unit 1 Docket No. STN 50-498 Licensee Event Report 2006-02, Simultaneous Inoperability of Two Essential Chilled Water Trains Pursuant to 10 CFR 50.73(a)(2)(i)(B), STP Nuclear Operating Company submits the attached Unit 1 Licensee Event Report 2006-02 regarding two essential chillers being inoperable simultaneously.
This event did not have an adverse effect on the health and safety of the public.
There are no commitments contained in this event report. Resulting corrective actions will be implemented in accordance with the Corrective Action Program.
If there are any questions regarding this submittal, please contact S. M. Head at (361) 972-7136 or me at (361) 972-7849.
ktoo E. D. Halpin Site Vice President/
Plant General Manager jtc/
Attachment: South Texas Unit 1 LER 2006-02 STI: 32014586
NOC-AE-06002025 Page 2 of 2 cc:
(paper copy)
(electronic copy)
Regional Administrator, Region IV U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 Richard A. Ratliff Bureau of Radiation Control Texas Department of State Health Services 1100 West 49th Street Austin, TX 78756-3189 Senior Resident Inspector U. S. Nuclear Regulatory Commission P. 0. Box 289, Mail Code: MN116 Wadsworth, TX 77483 C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704 A. H. Gutterman, Esquire Morgan, Lewis & Bockius LLP Mohan C. Thadani U. S. Nuclear Regulatory Commission Steve Winn Christine Jacobs Eddy Daniels NRG South Texas LP C. Kirksey City of Austin Jon C. Wood Cox Smith Matthews J. J. Nesrsta R. K. Temple E. Alarcon City Public Service
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6-2004)
, 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 South Texas, Unit 1 05000498 1 OF 8
- 4. TITLE Simultaneous Inoperability of Two Essential Chilled Water Trains
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE 1
- 8. OTHER FACILmES INVOLVED iFACILIEYNAMETDOCET NUMBE MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR I
05000
___INUMBER NO.05 0
IFACILITY NAME DOCKET NUMBER 03 31 2006 2006 - 002 -
00 05 30 2006 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITnED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply) o 20.2201(b)
[3 20.2203(a)(3)(i) 0 50.73(a)(2)(i)(C)
[I 50.73(a)(2)(vii) 10 20.2201(d)
El 20.2203(a)(3)(ii)
[I 50.73(a)(2)(ii)(A)
[I 50.73(a)(2)(viii)(A) o 20.2203(a)(1)
El 20.2203(a)(4)
[I 50.73(a)(2)(ii)(B) 0l 50.73(a)(2)(viii)(B)
[o 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 [I 20.2203(a)(2)(Ii)
[I 50.36(c)(1)(ii)(A)
[I 50.73(a)(2)(iv)(A) 0l 50.73(a)(2)(x) 0l 20.2203(a)(2)(iii) 0l 50.36(c)(2)
El 50.73(a)(2)(v)(A) 0 73.71 (a)(4) 10 20.2203(a)(2)(iv)
[j 50.46(a)(3)(ii)
[I 50.73(a)(2)(v)(B)
El 73.71 (a)(5) 100 13 20.2203(a)(2)(v)
[I 50.73(a)(2)(i)(A)
E3 50.73(a)(2)(v)(C)
[] OTHER El 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B)
[I 50.73(a)(2)(v)(D)
Specify in Abstract below or in =
(If more space is required, use additional copies of SUMMARY OF THE EVENT, INCLUDING DATES AND APPROXIMATE TIMES Unit 1 was operating at 100% power on March 31, 2006. Essential Chilled Water Trains A and C were in service. At 10:31, Essential Chilled Water Pump 11 B, Essential Chiller 12B, and Electrical Auxiliary Building (EAB) HVAC Train B were started, and EAB HVAC Train C was secured to support a scheduled equipment rotation from Train C to Train B. At 10:51, Essential Chilled Water Train C was declared inoperable because the Essential Chiller 12C breaker failed to open when the
b (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) identify and prevent the noted manufacturing errors.
- 3. Changed the scope and intent of essential chiller 78-week PMs to require the check of the terminations be performed last after all other maintenance has been completed and that the PM specify that all terminations on the chiller be checked.
- 4. Changed the maintenance procedure so that when replacing the hot gas bypass and prerotational vane motors, the motors are inspected/tested in the shop prior to installation. Inspections/tests include checking contact resistance values and verifying they change state, checking for proper rotation, and removing the back cover to verify there is no oil seepage.
- 5. Evaluate the availability and costs associated with new fault-tolerant digital chiller controllers and present a modification request to the Project Review Team.
- 6. Establish a Pre-installation Testing/Inspection Program similar to our current Post Maintenance Testing process so that more manufacturing defects can be found prior to the installation of parts in the plant.
VI.
PREVIOUS SIMILAR EVENTS
There have been no other violations of TS 3.0.3 in the past three years.
There were fifteen chiller events (not LERs) in 2004, nine in 2005, and three in 2006.