ML061880306
| ML061880306 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 06/29/2006 |
| From: | Mauldin D Arizona Public Service Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 102-05523/CDM/TNW/GAM, GL-04-002 | |
| Download: ML061880306 (4) | |
Text
Generic Letter 2004-02 LAM David Mauldin Mail Station 7605 Palo Verde Nuclear Vice President Tel: 623-393-5553 PO Box 52034 Generating Station Nuclear Engineering Fax: 623-393-6077 Phoenix, Arizona 85072-2034 102-05523-CDM/TNW/GAM June 29, 2006 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 Revision to Commitment Dates Associated with NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" By letter no. 102-05336, dated September 1, 2005, Arizona Public Service Company (APS) submitted to the NRC a response to Generic Letter (GL) 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors." In that submittal, APS made a number of regulatory commitments associated with containment sump improvements. By letter no.
102-05449, dated March 20, 2006, APS revised the completion dates of several of those commitments.
As described in SECY-06-0078, dated March 31, 2006, the industry has been developing an understanding of certain aspects of chemical and coating behavior in a post-LOCA environment and establishing an acceptable methodology for evaluating downstream effects. Those industry activities are ongoing.
As a result of the ongoing activities associated with containment sumps, APS must further revise the completion dates for several commitments described in the September 1, 2005 and March 20, 2006 submittals. Provided below is a table containing the complete listing of the regulatory commitments associated with APS' response to GL 2004-02 showing the original commitment due dates and the revised due dates or current status.
A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway 9 Comanche Peak 9 Diablo Canyon
- Palo Verde
- South Texas Project
- Wolf Creek
U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Revision to Commitment Dates Associated with NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" Page 2 REGULATORY COMMITMENT ORIGINAL REVISED (from APS letter no. 102-05336 DUE DATE DUE DATE or dated September 1, 2005)
STATUS
- 1. Evaluate the recommendations contained in the December 31, Completed Westinghouse downstream effects evaluation for 2005 PVNGS and establish an implementation schedule for appropriate recommendations.
- 2. Perform confirmatory head-loss testing of new March 31, March 31, strainer with plant specific debris to ensure an 2006 2007 adequate design.
- 3. Verify that a capture ratio of 97% or higher can be March 31, March 31, achieved in the final design of the new sump screen 2006 2007 to ensure that the fuel evaluation contained in the Westinghouse downstream effects evaluation is bounding.
- 4. Perform sump strainer structural evaluation to March 31, August 31, ensure seismic and operational integrity.
2006 2006
- 5. Validate allocated margins for Chemical Effects in May 31, 2006 March 31, strainer head-loss to ensure an adequate design.
2007
- 6. Perform a confirmatory containment latent debris June 30, 2006 Completed walkdown of PVNGS Units 1 and 3.
- 7. Perform a confirmatory containment unqualified June 30, 2006 Completed coating walkdown of PVNGS Units 1 and 3.
- 8. Review the existing programmatic controls for November 30, No Change containment coatings identified in the response to 2006 GL 98-04, "Potential for Degradation of the Emergency Core Cooling System and the Containment Spray System after a Loss-of-Coolant Accident Because of Construction and Protective Coating Deficiencies and Foreign Material in Containment," for their adequacy.
U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Revision to Commitment Dates Associated with NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" Page 3 REGULATORY COMMITMENT ORIGINAL REVISED (from APS letter no. 102-05336 DUE DATE DUE DATE or dated September 1, 2005)
STATUS
- 9. Review the existing programmatic and procedural November 30, No Change controls in place to prevent potentially transportable 2006 debris (insulation, signs and foreign material) in the containment building to ensure that the bounding assumptions in the design of the new strainers will be maintained.
- 10. Implement in Unit I changes to programs and 1R13 refueling No Change procedures to ensure and/or enhance the control of outage transportable debris in containment.
(approx.
May 31, 2007)
- 11. Implement in Unit 2 changes to programs and 2R1 3 refueling No Change procedures to ensure and/or enhance the control of outage transportable debris in containment.
(approx.
Nov. 30, 2006)
- 12. Implement in Unit 3 changes to programs and 3R13 refueling No Change procedures to ensure and/or enhance the control of outage transportable debris in containment.
(approx.
Dec. 31, 2007)
1R13 refueling No Change outage (approx.
May 31, 2007)
2R13 refueling No Change outage (approx.
Nov. 30, 2006)
3R1 3 refueling No Change outage (approx.
Dec. 31, 2007)
U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Revision to Commitment Dates Associated with NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" Page 4 REGULATORY COMMITMENT ORIGINAL REVISED (from APS letter no. 102-05336 DUE DATE DUE DATE or dated September 1, 2005)
STATUS
- 16. Remove installed Fiberfrax insulation in PVNGS 1R13 refueling No Change Unit 1.
outage (approx.
May 31, 2007)
- 17. Remove installed Fiberfrax insulation in PVNGS 2R13 refueling No Change Unit 2.
outage (approx.
Nov. 30, 2006)
- 18. Remove installed Fiberfrax insulation in PVNGS 3R13 refueling No Change Unit 3.
outage (approx.
Dec. 31, 2007)
- 19. By June 30, 2006, after plant specific strainer June 30, 2006 March 31, testing has been completed and the Westinghouse 2007 downstream effects evaluation for PVNGS has been evaluated, APS will submit an update to the NRC to report the validation of the allocated margins for chemical effects and identify any recommendations from the Westinghouse evaluation to be implemented.
If you have any questions, please contact Thomas N. Weber at (623) 393-5764.
Sincerely, CDM/TNW/GAM/gt cc:
B. S. Mallett M. B. Fields G. G. Warnick NRC Region IV Regional Administrator NRC NRR Project Manager NRC Senior Resident Inspector for PVNGS