DCL-05-014, 90-Day Response to NRC Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors (Correction)
| ML051030182 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 04/01/2005 |
| From: | Jacobs D Pacific Gas & Electric Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| DCL-05-014, DCL-05-032, GL-04-002, OL-DPR-80, OL-DPR-82 | |
| Download: ML051030182 (5) | |
Text
Pacific Gas and Electric Company Donna Jacobs Diablo Canyon Power Plant Vice President P. 0. Box 56 Nuclear Services Avila Beach, CA 93424 April 1, 2005 Fax: 805.545.4234 PG&E Letter DCL-05-032 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Units 1 and 2 90-Day Response to NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergencv Recirculation During Design Basis Accidents at Pressurized-Water Reactors" (Correction)
Dear Commissioners and Staff:
Pacific Gas and Electric (PG&E) Company's Letter DCL-05-014, dated March 4, 2005, submitted PG&E's 90-day response to the Nuclear Regulatory Commission's request for information pursuant to Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors," dated September 13, 2004. During final review of DCL-05-014, PG&E struck out an Enclosure 1 sentence discussing completing head loss testing by May 31, 2005. PG&E determined the sentence was unnecessary because head loss test results will be included with recirculation sump analysis results to be submitted by September 1, 2005. The marked-up page was inadvertently not replaced with a retyped page and DCL-05-014 was submitted with the strikethrough.
The attached Enclosure I includes the retyped (corrected) page and supersedes the enclosure submitted with PG&E Letter DCL-05-014. There are no other changes to the enclosure.
If you have any questions or require additional information, please contact Stan Ketelsen at 805-545-4720.
Sincerely, Donr Jacobs A
member of the STARS (Strategic Teaming and Resource Sharing)
Alliance Callaway
- Comanche Peak
- Diablo Canyon
- Palo Verde.
South Texas Project
- Wolf Creek
,A I I S
Document Control Desk April 1, 2005 Page 2 PG&E Letter DCL-05-032 jer/3664 Enclosures cc:
cc/enc:
Edgar Bailey, DHS Bruce S. Mallett David L. Prouix Diablo Distribution Girija S. Shukla A member of the STARS (Strategic Teaming and Resource Sharing)
Alliance Callaway
- Comanche Peak.
Diablo Canyon
- Palo Verde
- South Texas Project a Wolf Creek
PG&E Letter DCL-05-032 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION
)
In the Matter of
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PACIFIC GAS AND ELECTRIC COMPANY)
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Diablo Canyon Power Plant
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Docket No. 50-275 Facility Operating License No. DPR-80 Docket No. 50-323 Facility Operating License No. DPR-82 Units 1 and 2
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I AFFIDAVIT Donna Jacobs, of lawful age, first being duly sworn upon oath says that she is Vice President - Nuclear Services of Pacific Gas and Electric Company; that she has executed this 90-day response to Generic Letter 2004-02 on behalf of said company with full power and authority to do so; that she is familiar with the content thereof; and that the facts stated therein are true and correct to the best of her knowledge, information, and belief.
Donna Ja obs Vice Presid nt - Nuclear Services Subscribed and sworn to before me this 1st day of April 2005.
Notary Pubric/
County of San Luis ObiWVN State of California I.:IIC=MC CoatrAlon # 1397547 My Luis EOb Cm*
PG&E Letter DCL-05-032 90-Day Response to NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" This enclosure provides Pacific Gas and Electric (PG&E) Company's 90-day response to the Nuclear Regulatory Commission's (NRC) request for information pursuant to Generic Letter (GL) 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors," dated September 13, 2004. GL 2004-02 requested the following information to be provided within 90 days of the date of the safety evaluation report (SER) providing guidance for performing the requested containment sump evaluation. The NRC SER was issued by letter dated December 6, 2004, and titled, "Pressurized-Water Reactor Containment Sump Evaluation Methodology."
NRC Request I and 1(a)
All addressees are requested to provide the following information:
- 1.
Within 90 days of the date of the safety evaluation report providing the guidance for performing the requested evaluation, addressees are requested to provide information regarding their planned actions and schedule to complete the requested evaluation. The information should include the following:
(a)
A description of the methodology that is used or will be used to analyze the susceptibility of the ECCS [emergency core cooling system] and CSS
[containment spray system] recirculation functions for your reactor to the adverse effects identified in this generic letter of post-accident debris blockage and operation with debris-laden fluids identified in this generic letter.
Provide the completion date of the analysis that will be performed.
PG&E Response:
PG&E will analyze the susceptibility of the ECCS and CSS recirculation functions for Diablo Canyon Power Plant (DCPP) Units 1 and 2 to the adverse effects of post-accident debris blockage and operation with debris-laden fluids identified in GL 2004-02. PG&E will use the methodology provided by the Nuclear Energy Institute (NEI) document titled, "Pressurized Water Reactor Sump Performance Methodology," dated May 28, 2004, that was approved and supplemented by the NRC SER dated December 6, 2004. The sump performance methodology and the associated NRC SER have been issued collectively as NEI 04-07, "Pressurized Water Reactor Sump Performance Methodology," Revision 0, dated December 2004. The current licensing basis for DCPP Units 1 and 2, as well as 1
PG&E Letter DCL-05-032 plant-specific features may identify exceptions and or refinements to be taken to the guidance given in NEI 04-07. Exceptions or refinements to the guidance given in NEI 04-07, should they be taken, will be identified and the basis for them documented. This analysis is scheduled to be completed by September 1, 2005.
A specific element of the NEI 04-07 methodology that will be incorporated into PG&E's analysis is the performance of plant-specific head loss testing. Based on the results of the completed containment walkdown surveillances performed on DCPP Units 1 and 2, it is evident that calcium-silicate insulation is a significant debris source. To understand the behavior of calcium-silicate insulation and to determine the debris loading capacity of the current DCPP recirculation screens, PG&E will perform head loss testing on a prototype model of the DCPP Unit 1 and 2 recirculation screens.
NRC Request 1(b)
(b)
[Provide] A statement of whether you plan to perform a containment walkdown surveillance in support of the analysis of the susceptibility of the ECCS and CSS recirculation functions to the adverse effects of debris blockage identified in this generic letter. Provide justification if no containment walkdown surveillance will be performed. If a containment walkdown surveillance will be performed, state the planned methodology to be used and the planned completion date.
PG&E Response:
Containment walkdown surveillances have been completed for DCPP Units 1 and 2 to support the analysis of debris blockage requested by GL 2004-02. The walkdowns were performed using the guidance provided by NEI 02-01, "Condition Assessment Guidelines: Debris Sources Inside PWR Containments," Revision 1, dated September 2002. The DCPP Unit 1 containment walkdown surveillance was performed during refueling outage 1 R1 1, in the spring of 2002, and the DCPP Unit 2 containment walkdown surveillance was performed during refueling outage 2R1 1, in the spring of 2003. The DCPP Unit 1 containment walkdown surveillance was performed prior the issuance of Revision 1 of NEI 02-01, using the guidance provided by Revision 0 of NEI 02-01. The results of the Unit 1 surveillance have been reviewed and additional walkdown results have been incorporated to address the changes made by Revision 1 of NEI 02-01.
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