ML081420363
| ML081420363 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 05/09/2008 |
| From: | Mims D C Arizona Public Service Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 102-05857-DCM-GAM, GL-08-001 | |
| Download: ML081420363 (4) | |
Text
10 CFR 50.54(f)Z-AAW A subsidiar' of Pinnacle West Capital Corporation Dwight C. Mims Mail Station 7605 Palo Verde Nuclear Vice President Tel. 623-393-5403 P.O. Box 52034 Generating Station Regulatory Affairs and Plant Improvement Fax 623-393-6077 Phoenix, Arizona 85072-2034 102-05857-DCM/GAM May 09, 2008 Attn: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)Units 1, 2, and 3 Docket Nos. STN 50-528, 50-529, and 50-530 Three-Month Response to NRC Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems" The Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2008-01 on January 11, 2008, to request that each licensee evaluate its emergency core cooling system (ECCS), decay heat removal (DHR) system (the shutdown cooling system[SCS] at PVNGS), and containment spray system (CSS) licensing basis, design, testing, and corrective actions to ensure that gas accumulation is maintained less than the amount that challenges operability of these systems, and that appropriate action is taken when conditions adverse to quality are identified.
The NRC, in GL 2008-01, requested each licensee to submit a written response in accordance with 10 CFR 50.54(f) within 9 months of the date of the GL to provide the following information: (a) A description of the results of evaluations that were performed pursuant to the requested actions of the GL. This description should provide sufficient information to demonstrate that you are or will be in compliance with the quality assurance criteria in Sections III, V, XI, XVI, and XVII of Appendix B to 10 CFR Part 50 and the licensing basis and operating license as those requirements apply to the subject systems of the GL;A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway 0 Comanche Peak
- Diablo Canyon
- Palo Verde
- South Texas Project 0 Wolf Creek NRC Document Control Desk Three-Month Response to NRC Generic Letter 2008-01 Page 2 (b) A description of all corrective actions, including plant, programmatic, procedure, and licensing basis modifications that you determined were necessary to assure compliance with these regulations; and, (c) A statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.Additionally, the NRC requested that if a licensee cannot meet the requested response date, the licensee "shall provide a response within 3 months of the date of the GL." In the 3-month response, the licensee was requested to describe the alternative course of action that it proposes to take, including the basis for the acceptability of the proposed alternative course of action. By email dated April 3, 2008, from Mike Markley, NRC, to Glenn Michael, Arizona Public Service Company (APS), the NRC approved a request by APS to extend the response date for the 3-month letter by an additional month (to May 9, 2008).The enclosure to this letter contains the APS extended 3-month response to the requested information in GL 2008-01.This letter contains the commitments delineated in the enclosure.
If there are any questions or if additional information is needed, please contact Glenn A. Michael at (623) 393-5750.I declare under penalty of perjury that the foregoing is true and correct.Executed on -5 //0 g-(Date)Sincerely, DCM/SAB/GAM
Enclosure:
Extended Three-Month Response to NRC Generic Letter 2008-01 cc: E. E. Collins Jr. NRC Region IV Regional Administrator M. T. Markley NRC NRR Project Manager R. I. Treadway NRC Senior Resident Inspector for PVNGS Enclosure Palo Verde Nuclear Generating Station Extended Three-Month Response to NRC Generic Letter 2008-01 NRC Generic Letter (GL) 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems," dated January 11, 2008, was issued to request information from licensees regarding compliance with current licensing and design basis requirements, applicable regulatory requirements, and control measures in place for maintaining compliance for the following systems:* Emergency Core Cooling System (ECCS),* Shutdown Cooling System (SCS), and* Containment Spray System (CSS).GL 2008-01 requests a complete and thorough evaluation of the design of the ECCS, SCS and CSS. To validate the as-built conditions of these systems, additional physical design verification walkdowns may be required.
These walkdowns cannot be completed in the three Palo Verde units prior to the GL 2008-01 9-month response due date of October 14, 2008, because portions of these walkdowns cannot be performed at power for the following reasons: " Restrictions on removal of insulation from piping while the systems are required to be operable (in both the containment and auxiliary buildings).
- Restrictions on the erection of scaffolding and providing shielding within the containment around operating systems." -Prolonged containment entries and high radiation exposure rates during plant operation.
Alternative Course of Action 1. APS commits to perform physical design verification walkdowns of the ECCS, SCS and CSS to validate the as-built conditions for Unit 1 for GL 2008-01 prior to startup from the Unit 1 R14 refueling outage expected by 11/30/08.2. APS commits to perform physical design verification walkdowns of the ECCS, SCS and CSS to validate the as-built conditions for Unit 3 for GL 2008-01 prior to startup from the Unit 3 R14 refueling outage expected by 05/31/09.3. APS commits to perform physical design verification walkdowns of the ECCS, SCS and CSS to validate the as-built conditions for Unit 2 for GL 2008-01 prior to startup from the Unit 2 R1 5 refueling outage expected by 11/30/09.4. APS commits to submit to the NRC any required additional corrective actions resulting from performing the design validation walkdowns for Unit 1, 90 days after completion of the Unit 1 R14 refueling outage. (Est. 2/28/09)1 GL 2008-01 Extended 3 Month Response 5. APS commits to submit to the NRC any required additional corrective actions resulting from performing the design validation walkdowns for Unit 3, 90 days after completion of the Unit 3 R14 refueling outage. (Est. 8/29/09)6. APS commits to submit to the NRC a final evaluation summarizing the findings and corrective actions resulting from the design validation walkdowns performed in all three PVNGS Units, 90 days after completion of the Unit 2 R15 refueling outage. (Est. 2/28/10)Basis for the Acceptability of the Proposed Alternative Course of Action Per GL 2008-01, APS will complete and submit a design evaluation of the ECCS, SCS, and CSS by October 14, 2008, which will be based on the available information for those systems. This evaluation will review available licensing and design documentation, design modifications, and any previous design level walkdowns performed on the three Palo Verde Units. Several walkdowns have been performed in each of the three Units as a result of internal and industry operating experience issues.In addition, modifications have been implemented to add venting locations.
These walkdowns and modifications were performed well before the issuance of GL 2008-01 and therefore, did not consider all the technical aspects discussed in the GL and its attached Technical Considerations document.
The additional walkdowns planned after the GL 2008-01 9-month submittal due date of October 14, 2008, are considered confirmatory.
Even without these confirmatory walkdowns complete in support of the GL 2008-01 response, the evaluation of the available design documentation and the previous walkdowns performed will result in a very thorough and accurate design evaluation of the subject systems.2