05000529/LER-2004-002, On 07/14/2004 Reactor Tripped on Low Departure from Nucleate Boiling Ratio (DNBR)
| ML042600333 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 09/10/2004 |
| From: | Danni Smith Arizona Public Service Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 192-01152-DMS/SAB/DLK LER 04-002-00 | |
| Download: ML042600333 (6) | |
| 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)(ii) 10 CFR 50.73(a)(2)(vi)(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 |
| 5292004002R00 - NRC Website | |
text
-A FS A suhsidiary of Pinnacle 11est Capital Corporalion 10 CFR 50.73 Palo Verde Nuclear Generating Station David M. Smith Tel.
623-393-6116 Mail Station 7602 Plant Manager Fax.
623-393-6077 P.O. Box 52034 Nuclear Production e-mail: DSMITH10@apsc.com Phoenix, AZ 85072-2034 192-01152-DMS/SAB/DLK September 10, 2004 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Unit 2 Docket No. STN 50-529 License No. NPF-51 Licensee Event Report 2004-002-00 Attached please find Licensee Event Report (LER) 50-529/2004-002-00 prepared and submitted pursuant to 10 CFR 50.73. This LER reports an automatic reactor trip on low DNBR following a large load reject reactor power cutback.
In accordance with 10 CFR 50.4, a copy of this LER is being forwarded to the NRC Region IV Office and the Senior Resident Inspector. If you have questions regarding this submittal, please contact Daniel G. Marks, Section Leader, Regulatory Affairs, at (623) 393-6492.
The corrective actions described in this LER are not necessary to maintain compliance with regulations. Arizona Public Service Company makes no commitments in this letter.
Sincerely, DMS/SAB/DLK Attachment cc:
B. S. Mallett NRC Region IV Regional Administrator M. B. Fields NRC NRR Project Manager N. L. Salgado NRC Senior Resident Inspector for PVNGS
4RC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/3012007 6-2004)
Estimated burden per response to comply with this mandatory collection request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Reported lessons learned are Incorporated Into the licensing process and fed back to Industry. Send comments regarding burden estimate to the Records and IFOIA/Privacy Service Branch (T-5 F52), U.S.
LICENSEE EVENT REPORT (LER)
Nuclear Regulatory Commission, Washington, DC 20555 0001, or by Inernet e-mail to lnfocollects~nrc.gov, and to the Desk Officer, Office of Information and RegulatoryAffairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to Impose an information (See reverse for required number of collection does notdisplaya currentlyvalid OMBcontrol nurnber, the NRC may sfor each block) not conduct or sponsor, and a person Is not required to respond to, the digits/characters frecblk)Information collection.
- 3. PAGE Palo Verde Nuclear Generating Station Unit 2 05000529 1 OF 5
- 4.
TITLE Reactor Trip on Low DNBR
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED S FACIUTY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBEN REV MONTH DAY YEAR None 05000 FACILITY NAME DOCKET NUMBER 07 14 2004 2004 - 002 -
00 09 10 2004 None 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check al that apply)
- 1 20.2201 (b) 171 20.2203(a)(3)(i) n 50.73(a)(2)(i)(C) n 50.73(a)(2)(vii) 1 20.2201(d) 17 20.2203(a)(3)(i)
E 50.73(a)(2)(ii)(A)
En 50.73(a)(2)(viii)(A) 1l 20.2203(a)(1)
E 20.2203(a)(4)
El 50.73(a)(2)(ii)(B) a 50.73(a)(2)(viii)(B)
El 20.2203(a)(2)(;)
l 20.36(c(1)(i)(A) n 50.73(a)(2)(ii))
El 50.73(a)(2)(vi)(A)
- 10. POWER LEVEL E 20.2203(a)(2)(ii)
El 50.36(c)(1)(ii)(A)
JR 50.73(a)(2)(iv)(A) 17 50.73(a)(2)(x) 1 20.2203(a)(2)(ii)
E 50.36(c)(2) n 50.73(a)(2)(v)(A)
E 73.71(a)(4)
C 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
E 73.71 (a)(s) 100 r
20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A) n 50.73(a)(2)(v)(C)
E OTHER C 20.2203(a)(2)(vi)
E 50.73(a)(2)(i)(B)
E 50.73(a)(2)(v)(D)
Specify In Abstract below or In (If more space is required, use additional copies of (it 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)
Calculation TA-1 3-C00-2004-004, "Determination of a new ARM5 value for Units 1 and 2 Cycle 12 & Unit 3 Cycle 11," was revised to establish ARM5 values that would minimize the possibility of an automatic reactor trip following a reactor power cutback while at the same time not inhibit the required trip protection should the integrated system response following a reactor power cutback fall outside the design basis. (ARM5 is one of the CPC addressable constants for planar radial peaking factor.) The new ARM5 values have been incorporated into all three Unit's CPCs.
8. PREVIOUS SIMILAR EVENTS
On June 7, 2004 Unit 3 experienced a main turbine control system malfunction that resulted in a reactor power cutback followed by an automatic reactor trip on low DNBR (LER 50-530/2004-002-00). The investigation and corrective actions associated with the June 7 event had not been completed at the time the event discussed in this LER occurred.