05000528/LER-2003-002, Manual Reactor Trip Due to Degraded Main Condenser Tube Plug
| ML031400058 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 05/15/2003 |
| From: | Overbeck G Arizona Public Service Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 192-01120-GRO/SAB/REB LER 03-002-00 | |
| Download: ML031400058 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(B) |
| 5282003002R00 - NRC Website | |
text
1 OCFR50.73 Palo Verde Nuclear Generating Station Gregg R. Overbeck Senior Vice President Nuclear Mail Station 7602 TEL (623) 393-5148 P.O. Box 52034 FAX (623) 393-6077 Phoenix, AZ 85072-2034 192-01120-GRO/SAB/REB May 15, 2003 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station P1-37 Washington, DC 20555-0001
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Unit 1 Docket No. STN 50-528 License No. NPF-41 Licensee Event Report 2003-002-00 Attached please find Licensee Event Report (LER) 50-528/2003-002-00 that has been prepared and submitted pursuant to 10 CFR50.73 (a) (2) (iv) (A). This LER reports a condition in which Unit 1 licensed control room personnel initiated a manual reactor trip in response to a degraded main condenser tube plug.
In accordance with 10 CFR 50.4, a copy of this LER is being forwarded to the NRC Regional Office, NRC Region IV and the Resident Inspector. If you have questions regarding this submittal, please contact Daniel G. Marks, Section Leader, Regulatory Affairs, at (623) 393-6492.
Arizona Public Service Company makes no commitments in this letter.
Sincerely, GRO/SAB/REB/kg Xf Attachment cc:
Regional Administrator, NRC Region IV N. L. Salgado J. N. Donohew (all with attachment) 5- -- )
APPROVED BY OMB NO. 3150-0104 EXPIRES 6-30-2001 NRC FORM 366 U.S. NUCLEAR REGULATORY
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
FACILITY NAME (1)
DOCKET NUMBER (2)
PAGE (3)
Palo Verde Nuclear Generating Station Unit 1 l 05000528 l
1 OF 4
TITLE (4)
Manual Reactor Trip Due to Degraded Main Condenser Tube Plug EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
SEQUENTIAL_FACILITY_NAME_DOCKET NUMBER MONTH DAY YEAR YEAR SEUENTIAL REv NO MONTH DAY YEAR 05000 INUMBER REV0 03 27 2003 2003 -
002 00
??
??
2003 FACILITY NAME 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) (11)
MODE (9) 1
=
20.2201 (b)
=
20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
POWER LEVEL 098 20.2201 (d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x)
(10) 20.2203(a)(1) 50.36(c)(1)(i)(A)
X 50.73(a)(2)(iv)(A) 73.71 (a)(4) 3
- ?i=S 20.2203(a)(2)(i) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(ii) 50.36(c)(2) 50.73(a)(2)(v)(B)
OTHER 20.2203(a)(2)(iii) 50.46(a)(3)(ii)
_ 50.73(a)(2)(v)(C)
Specify in Abstract below or in NRC Form 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73Ca)(2)(v)(D) 36 ggW'- g20.2203(a)(2)(v) 50.73(a)(2)(i)(B) 50.73(a)(2)(vii) 20.2203(a)(2)(vi)
=
50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B)
LICENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER (Include Area Code)
Daniel G. Marks, Section Leader, Reaulatory Affairs 623-393-6492 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE
CAUSE
SYSTEM COMPONENT MANU REPORTABLE
CAUSE
SYSTEM COMPONENT FACTURER TO EPIX FACTURER TO EPIX B
SG TBG Y
SUPPLEMENTAL REPORT EXPECTED (14)
EXPECTED MONTH DAY YEAR YES (If yes, complete EXPECTED SUBMISSION DATE)
X INO l DATE (15)
ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)
On March 27, 2003 with Unit I operating in Mode 1, Power Operation, at approximately 97 per cent power, a HOTWELL A HIGH SODIUM alarm was received in the chemistry laboratory at approximately 09:27 MST.
Chemistry personnel responded to the alarm and determined that hotwell A sodium was trending up. The condensate system was operating in the demineralizer by-pass mode at the time of the event. Control room
- - personnel were notified and the abnormal operating (AO) procedure, Condenser Tube Rupture, 40AO-9ZZ10, was entered. Steam generator sodium levels continued to increase and at approximately 09:43 MST, in accordance with the procedure, the Control Room Supervisor (CRS) directed a manual reactor trip be initiated.
All control rods fully inserted and the plant was stabilized in Mode 3, Hot Standby. No other safety systems actuated and none were required. Problems were encountered with maintaining letdown flow but the control room operators were able to control pressurizer level within acceptable limits. The plant was cooled down to Mode 5, Cold Shutdown, to cleanup SG chemistry and to repair the cause of the intrusion to the hotwell.
The cause of the sodium intrusion into the hotwell was determined to be a degraded tube plug that had been installed previously to isolate a leaking condenser tube.
No other similar events have been reported by Palo Verde in the past three years.
NRC FORM 366 (1-2001)
(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 Forn 366A) (17)
7. PREVIOUS SIMILAR EVENTS
There has been no similar event reported to the NRC by the Palo Verde Nuclear Generating Station in the past three years.