05000529/LER-2005-004, Re Technical Specification Required Shutdown Due to Core Protection Calculators Inoperable

Re Technical Specification Required Shutdown Due to Core Protection Calculators Inoperable

ML053040068
Person / Time
Site:	Palo Verde
Issue date:	10/18/2005
From:	Eubanks C Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05360-CE/CKS/REB LER 05-004-00
Download: ML053040068 (7)

LER-2005-004, Re Technical Specification Required Shutdown Due to Core Protection Calculators Inoperable

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2) 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
5292005004R00 - NRC Website

text

10 CFR 50.73 LjAMS A subsidiary of Pinnacle vJest Capital Corporation Palo Verde Nuclear Generating Station Cliff Eubanks Vice President Nuclear Operations Tel (623) 393-6116 Fax (623) 393-6077 Mail Station 7602 PO Box 52034 Phoenix, Arizona 85072-2034 102-05360-CE/CKS/REB October 18, 2005 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 2005-004-00 Attached please find Licensee Event Report (LER) 50-529/2005-004-00 prepared and submitted pursuant to 10 CFR 50.73. This LER reports a shutdown required by Technical Specifications based on the inoperability of all four channels of the Core Protection Calculators.

In accordance with 10 CFR 50.73(d), copies of this LER are being forwarded to the NRC Regional Office, NRC Region IV 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.

Arizona Public Service Company makes no commitments in this letter.

Sincerely, CE/CKSIREB/ca Attachment cc:

B. S. Mallett M. B. Fields G. G. Wamick NRC Region IV Regional Administrator NRC NRR Project Manager - (send electronic and paper)

NRC Senior Resident Inspector for PVNGS 0

C--1.-1c;) C;

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0613012007 (6-2004)

, the NRC may foar each block) not conduct or sponsor, and a person Is not required to respond to. the digits/characters for each bloc)Information collection.

3. PAGE Palo Verde Nuclear Generating Station Unit 2 05000529 1 OF 6

4. TITLE Technical Specification Required Shutdown Due to Core Protection Calculators Inoperable

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED S

UT RVFACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER REV MONTH DAY YEAR None 05000 FACILITY NAME DOCKET NUMBER 08 22 2005 2005 - 004 -

00 10 18 2005 None 05000

9. OPERATING MODE 11.THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check allthatapply) o 20.2201(b) a 20.2203(a)(3)(i)

El 50.73(a)(2XiXC)

O 50.73(aX2)(vii) 1 0 20.2201(d) 0 20.2203(aX3)(ii) 0 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viiiXA)

O 20.2203(a)(1)

[0 20.2203(a)(4) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(2)(viii)(B)

Eo 20.2203(a)(2Xi) 0 50.36(cX1)(i)(A) 0 50.73(a)(2)(iii) 0l 50.73(a)(2)(ix)(A)

10. POWER LEVEL 0 20.2203(a)(2Xii)

El 50.36(cX1)(iiXA) 0 50.73(a)(2)(iv)(A)

E 50.73(a)(2)(x) o 20.2203(a)(2)(iii) 0 50.36(c)(2) 0 50.73(a)(2)(v)(A) 0 73.71(a)(4) 0 20.2203(a)(2)(iv) 0 50.46(aX3)(ii) 0 50.73(a)(2)(v)(B)

El 73.71(a)(5) 99 0 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(C) 0 OTHER o 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B) 0 50.73(aX2)(v)(D)

Specify In Abstract below or In (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)

The condition would not have prevented the fulfillment of any safety function and did not result in a safety system functional failure as defined by 10 CFR 50.73(a)(2)(v).

6.

CAUSE OF THE EVENT

The investigation into the cause of this event is ongoing. Preliminary results indicate the direct cause is that a CPC system requirement specification was not properly translated into the CPC software by the vendor. If the completed investigation report includes information which would substantively change the reader's perception of the event, an LER supplement will be submitted.

7.

CORRECTIVE ACTIONS

On August 25, 2005 activities were completed to install CPC software version 6.3 in all four channels of Unit 2 CPCs.

After the root cause investigation is completed any identified corrective actions, including actions to prevent recurrence, will be entered into the corrective action process.

8.

ADDITIONAL INFORMATION

The CPCs in Unit 2 were upgraded in November 2003. Units 1 is scheduled to receive the upgraded CPC system in the refueling outage currently in progress and Unit 3 is scheduled to receive the upgraded CPC system in a future refueling outage. The problem identified in this LER is therefore limited to Unit 2. Changes will be made to Units 1 and 3 upgraded CPCs, prior to their installation, to correct the problem.

9.

PREVIOUS SIMILAR EVENTS

In the past three years, Palo Verde reported reactor shutdowns required by Technical Specifications but none associated with the same root cause.