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Update for Response to Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors.
	ML071280478
Person / Time
Site:	Callaway
Issue date:	05/01/2007
From:	Fitzgerald D; AmerenUE
To:	; Document Control Desk, NRC/NRR/ADRO
References
	GL-04-002, ULNRC-05408
	Download: ML071280478 (9)
	v • d • e

AmerenUE PO Box 620 Callaway Plant Fulton, MO 65251 May 1, 2007 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Stop P1-137 Washington, DC 20555-0001 ULNRC-05408 Ladies and Gentlemen:

DOCKET NUMBER 50-483 WAmeren CALLAWAY PLANT UNIT 1 UE UNION ELECTRIC CO.

FACILITY OPERATING LICENSE NPF-30 UPDATE FOR RESPONSE TO GENERIC LETTER 2004-02, "POTENTIAL IMPACT OF DEBRIS BLOCKAGE ON EMERGENCY RECIRCULATION DURING DESIGN BASIS ACCIDENTS AT PRESSURIZED-WATER REACTORS"

References:

1. AmerenUE Letter ULNRC-05124, dated March 7, 2005

2. AmerenUE Letter ULNRC-05194, dated September 1, 2005.

3. NRC letter dated March 28, 2006, from Catherine Haney, NRC, to Holders of Licenses for Pressurized-Water Reactors.

4. AmerenUE Letter ULNRC-05295, dated May 30, 2006

5. NRC letter dated January 4, 2007, from Catherine Haney, NRC, to Holders of Licenses for Pressurized-Water Reactors In accordance with 10 CFR 50.54(f), this letter provides an update to the Union Electric Company (AmerenUE) response to Nuclear Regulatory Commission (NRC)

Generic Letter (GL) 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors," for Callaway Plant. Pursuant to AmerenUE's commitments for addressing the concerns of GL 2004-02 for Callaway, this update reflects recent completion of the physical modifications identified for the facility. Commitments related to remaining activities to be completed in response to GL 2004-02 are being revised as noted in this submittal. Scheduled completion of the remaining activities per these revised commitments is within a timeframe identified to be acceptable by the NRC for the industry, as further explained below.

On September 13, 2004 the NRC issued GL 2004-02 to (1) request that addressees perform an evaluation of the Emergency Core Cooling System (ECCS) and a subsidiaryofAmeren Corporation

ULNRC-05408 May 1, 2007 Page 2 Containment Spray System (CSS) recirculation functions in light of the information provided in the GL and, if necessary, take additional actions to ensure system function, and (2) require addressees to provide the NRC a written response in accordance with 10 CFR 50.54(f).

AmerenUE's initial response to Generic Letter 2004-02 was provided via its letter dated March 7, 2005 (Reference 1). It provided some of the information required to be submitted, and it provided an initial list of commitments made by AmerenULE in response to the GL. Additional information required per the GL, along with an expanded list of commitments, was subsequently provided by AmerenUE letter dated September 1, 2005 (Reference 2). One commitment was revised as described in the letter, and AmerenUE committed to provide an update on or by June 1, 2006.

In February 2006, the NRC issued a request for additional information (RAI) for plant responses to GL 2004-02. The RAI was followed by NRC letter dated March 28, 2006 (Reference 3) in which the NRC described an alternative approach for responding to the NRC's RAI regarding GL 2004-02. Per that letter, plants installing strainers during their refueling outages after 2006 (such as Callaway) were expected to provide the remaining information needed to fully address GL 2004-02 within 90 days of outage completion but not later than December 31, 2007.

On May 30, 2006, AmerenUE submitted a letter (Reference 4) providing an update for its response to GL 2004-02 in accordance with the commitment made in its June 1, 2006 letter. The letter described progress made to date, including completion of mock-up strainer head loss testing, development of the design for new sump strainers to be installed at Callaway, and finalization of the plans for installing the new strainers during the forthcoming refueling outage. i.e., Refuel 15. Additional commitments and/or changes to ongoing commitments were addressed in the letter, as expected completion dates were revised in accordance with Reference 3. Affected activities included those related to the information to be provided in response to the NRC's RAI. Completion dates for those activities were revised to "within 90 days of Refuel 15 completion." Other activities were identified for completion by December 31, 2007 (also in accordance with Reference 3).

By letter dated January 4, 2007 (Reference 5) the NRC provided additional guidance regarding the alternative approach for responding to the RAI related to GL 2004-02, as previously addressed in the NRC's March 28, 2006 letter. Per the new/updated guidance provided in the letter, the NRC noted that it expects licensees to submit a complete response for addressing GL 2004-02 as soon in 2007 as the information and analysis results are available, but no later than December 31, 2007.

At present, Refuel 15 is nearing completion at Callaway Plant. This letter provides an update for AmerenUE's response to GL 2004-02 in light of recently completing the physical modifications to the facility per AmerenUE's commitments, i.e., installation

ULNRC-05408 May 1, 2007 Page 3 of the new sump strainers, and in light of the guidance provided in the NRC's January 4, 2007 letter. The status of remaining activities is included in the attached list of commitments, i.e. Attachment I of this letter. Some of the commitments are being revised since they involve activities that will not be completed prior to restart from the current outage (Refuel 15) or within 90 days after completion of the outage, as applicable and previously anticipated. For some of these activities, AmerenUE is awaiting the completion of ongoing industry efforts and vendor work in order to complete the final evaluations. The commitment changes are being submitted pursuant to the guidance of NEI 99-04, "Guidelines for Managing NRC Commitment Changes," as endorsed in Regulatory Issue Summary (RIS) 2000-017, "Managing Regulatory Commitments Made by Power Reactor Licensees to the NRC Staff."

As noted above, an updated list of AmerenUE's commitments regarding GL 2004-02 is provided as Attachment 1. The list is based on the list provided in AmerenUE's May 30, 2006 letter (Reference 4). This list of commitments supersedes the list provided per Reference 4, as it provides the current status of each commitment.

Although some commitments are being revised in order to extend the completion times for certain activities, the schedule for completion of the remaining activities identified as commitments in Attachment 1 remains in accordance with the schedule established per Reference 5. Accordingly, the remaining activities are due to be completed by December 31, 2007.

For any questions concerning this matter, please contact Dave Shafer at (314) 554-3104 or 573-676-4722.

I declare under penalty of perjury that the foregoing is true and correct.

Sincerely, Executed on: 'ZO)7 e7 4

avid T. Fitzgerald Manager - Regulatory Affairs BFH/TBE/slk : Updated List of Commitments

ULNRC-05408 May 1, 2007 Page 4 cc: Mr. Bruce S. Mallett Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-4005 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Jack N. Donohew (2 copies)

Licensing Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop O-7D1 Washington, DC 20555-2738 Missouri Public Service Commission Governor Office Building 200 Madison Street PO Box 360 Jefferson City, MO 65102-0360 Mr. Ron Reynolds Director Missouri State Emergency Management Agency PO Box 116 Jefferson City, MO 65102

ULNRC-05408 May 1, 2007 Page 5 bcc: C. D. Naslund A. C. Heflin D. T. Fitzgerald G. A. Hughes D. E. Shafer S. L. Gallagher (100)

L. M. Belsky (NSRB)

K. A. Mills S. L. Abel M. D. Brandes B. F. Holdemess A160.0761 Certrec Corporation 4200 South Hulen, Suite 422 Fort Worth, TX 76109 (Certrecreceives ALL attachments as long as they are non-safeguards and public disclosed).

Send the following without attachments:

Ms. Diane M. Hooper Mr. Dennis Buschbaum Supervisor, Licensing TXU Power WCNOC Comanche Peak SES P.O. Box 411 P.O. Box 1002 Burlington, KS 66839 Glen Rose, TX 76043 Mr. Scott Bauer Mr. Stan Ketelsen Regulatory Affairs Manager, Regulatory Services Palo Verde NGS Pacific Gas & Electric P.O. Box 52034, Mail Stop 104/5/536 Mail Station 7636 P.O. Box 56 Phoenix, AZ 85072-2034 Avila Beach, CA 93424 Mr. Scott Head Mr. John O'Neill Supervisor, Licensing Pillsbury Winthrop Shaw Pittman LLP South Texas Project NOC 2300 N. Street N.W.

Mail Code N5014 Washington, DC 20037 P.O. Box 289 Wadsworth, TX 77483

ULNRC-05408 Page 1 of 4 UPDATED LIST OF COMMITMENTS The following table identifies those actions originally committed to by AmerenUE in its May 30, 2006 letter to the NRC. The table provides a status update and revised commitment due dates. Please direct questions regarding these commitments to Mr. David E. Shafer at 314-554-3104 or 573-676-4722.

COMMITMENT CURRENT STATUS DUE DATE / EVENT

1. Containment walkdown to provide current assessment Completed during Refuel Outage 14 (Fall 2005). Complete of Callaway's containment coatings and latent debris.

2 The following corrective action activities will be completed:

a. Replacement sump strainer structural analysis. The structural analysis of the replacement strainers is Complete complete and was issued prior to restart from Refuel 15 (Spring 2007).

b. Downstream effects evaluation. Initial downstream evaluations have been performed; December 31, 2007 however, refinements are being pursued using test data and input from PWROG/NRC discussions concerning nuclear fuel.

c. Upstream effects evaluation. Upstream evaluations have been performed and will be December 31, 2007 included in the Westinghouse team analysis summary report, item 4.f. of this table.

d. Resolution of debris generation calculation Zone of influence testing has been performed and is Complete unverified assumption of 5D ZOI for qualified documented in Westinghouse WCAP-16568-P.

coatings (via coatings testing).

e Replacement sump screen head loss testing. Strainer performance testing was performed during the December 31, 2007 week of March 13, 2006. Additional testing and evaluations may be necessary as a result of industry efforts related to chemical effects.

ULNRC-05408 Page 2 of 4 COMMITMENT CURRENT STATUS DUE DATE / EVENT

3. Provide an update of the information contained in section The analyses are proceeding and refinements are being December 31, 2007 2(c) regarding analysis methodology, pursued. The update of information contained in section 2(c) of Reference 1 will be provided after completion of Item 4.f.

of this table.

4. The following evaluations and testing will be completed:

a. Industry chemical effects testing. Industry chemical effects tests have been completed. Complete

b. NEI 04-07 debris generation calculation. The debris generation calculation has been performed and will December 31, 2007 be included in the Westinghouse team analysis summary report, item 4.f. of this table. A revision to the current debris generation calculation is being conducted to utilize refinements based on testing or additional analysis.

c. NEI 04-07 debris transport calculation. The debris transport calculation has been performed and will December 31, 2007 be included in the Westinghouse team analysis summary report, item 4.f. of this table. A revision to the current debris transport calculation is being conducted to utilize several refinements based on testing or additional analysis.

d. Evaluation of chemical effects impact on sump- WCAP 16530-NP guidance was used as part of the strainer December 31, 2007 strainer head loss. performance testing performed during the week of March 13, 2006. Additional evaluations or testing may be necessary as a result of the NRC Safety Evaluation currently being performed for WCAP 16530-NP.

e. Confirmation that the replacement sump strainer The strainer performance test report based on the March 13, December 31, 2007 design provides for available NPSH to be in excess of 2006 strainer testing has been completed and has been used in required NPSH. the determination of adequate NPSH. Additional testing and evaluations may be necessary as a result of industry efforts related to chemical effects.

f. Completion of the final site acceptance review of the Several of the items contained in the final report have been December 31, 2007 Westinghouse team analysis summary report. completed but the final report will not be issued until all items are completed.

ULNRC-05408 Page 3 of 4 COMMITMENT CURRENT STATUS DUE DATE / EVENT

5. Callaway will complete the following items during Refuel 15:

a. Replacement of containment recirculation sump Installation of the new strainers was complete during Complete strainers. Refuel 15 (Spring 2007).

b. Modification of containment debris barriers and Installation of debris barriers was completed during Complete interceptors as required. Refueling Outage 15. Use of debris interceptors was determined to not be necessary and is not being pursued any further at this time.

c Evaluation and implementation of potential Implementation of potential modification to the safety December 31, 2007 modification to the safety injection system to injection system is dependant on the refinements address downstream effects. mentioned in Item 2.b. of this table. Based on the evaluations completed to date, the downstream effects evaluations have been performed and conclude that there are no modifications necessary for the Safety Injection system. However, as GSI-191 evaluations are finalized, this conclusion will be re-evaluated to determine if additional efforts are required.

6. Callaway will complete removal of containment spray Removal of containment spray system (CSS) pump December 31, 2007 system (CSS) pump cyclone separators, if required cyclone separators is dependent on the results of the based on the results of the downstream effects downstream effects evaluation, Item 2.b. of this table.

evaluation.

7. The following programs and controls will be Evaluations of changes required to programs and controls December 31, 2007 implemented at Callaway to control debris sources. have not been completed.

a. Changes to design change process procedures to ensure that necessary engineering evaluations will be performed for plant design that either directly or indirectly affects containment, ECCS, or CSS.

b. Changes to containment entry and material control procedure requirements for control of materials during work activities conducted in the containment.

ULNRC-05408 Page 4 of 4 COMMITMENT CURRENT STATUS DUE DATE / EVENT

7. (continued)

c. Changes to programs and procedures that have the potential to add tags and labels inside containment.

d. Implementation of a containment coatings assessment program

e. Implementation of a containment latent debris assessment program f Implementation of changes to the inspection processes for the installed sump strainers

8. A final response will be submitted to the NRC to December 31, 2007 provide a final status of actions requested by Generic Letter 2004-02.