ML080920170

Revision to Reactor Pressure Vessel Surveillance Capsule Withdrawal Schedule

ML080920170
Person / Time
Site:	Calvert Cliffs
Issue date:	04/09/2008
From:	Pickett D NRC/NRR/ADRO/DORL/LPLI-1
To:	Spina J Calvert Cliffs
Pickett D, NRR/DORL, 415-1364
References
TAC MD8235
Download: ML080920170 (5)

Text

April 9, 2008 Mr. James A. Spina, Vice President Calvert Cliffs Nuclear Power Plant, Inc.

Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702

SUBJECT:

CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO. 1 - REVISION TO REACTOR PRESSURE VESSEL SURVEILLANCE CAPSULE WITHDRAWAL SCHEDULE (TAC NO. MD8235)

Dear Mr. Spina:

By letter dated March 5, 2008, Calvert Cliffs Nuclear Power Plant, Inc. submitted for Nuclear Regulatory Commission (NRC) staff review a request for revising the withdrawal schedule for the reactor pressure vessel (RPV) surveillance capsule at the 104° location for Calvert Cliffs Nuclear Power Plant (CCNPP), Unit No. 1. The purpose of the licensees submittal was to provide a surveillance capsule withdrawal schedule for CCNPP, Unit No. 1 that is consistent with the most recent projected extended end-of-license fluence at one-quarter of the RPV wall thickness.

The NRC staff has completed its review and concludes that the proposed withdrawal schedule for the CCNPP, Unit No. 1 capsule mentioned above meets the requirements of the American Society for Testing and Materials Standard E185-82, Standard Practice for Conducting Surveillance Tests for Light-Water Cooled Nuclear Power Reactor Vessels, and Appendix H to Title 10 of the Code of Federal Regulations Part 50, Reactor Vessel Material Surveillance Program Requirements. The staffs safety evaluation is enclosed.

Please contact me at 301-415-1364 if you have any questions.

Sincerely,

/RA/

Douglas V. Pickett, Senior Project Manager Plant Licensing Branch I-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-317

Enclosure:

Safety Evaluation cc w/encl: See next page

ML080920170 OFFICE LPLI-1/PM LPLI-1/LA CVIB/BC LPLI-1/BC NAME DPickett SLittle MMitchell as signed MKowal on DATE 4 /4/ 08 4 / 8/ 08 3 / 20 / 08 4 /9/ 08

Calvert Cliffs Nuclear Power Plant, Unit Nos. 1 and 2 cc:

Regional Administrator, Region I Mr. Michael J. Wallace, President U.S. Nuclear Regulatory Commission Constellation Energy Nuclear Group, LLC 475 Allendale Road 750 East Pratt Street, 18th Floor King of Prussia, PA 19406 Baltimore, MD 21202 Ms. Kristen A. Burger, Esquire Mr. John M. Heffley, Senior Vice President Maryland People's Counsel and Chief Nuclear Officer 6 St. Paul Centre Constellation Energy Nuclear Generation Suite 2102 Group Baltimore, MD 21202-1631 111 Market Place Baltimore, MD 21202 Ms. Patricia T. Birnie, Esquire Co-Director President Maryland Safe Energy Coalition Calvert County Board of P.O. Box 33111 Commissioners Baltimore, MD 21218 175 Main Street Prince Frederick, MD 20678 Mr. Roy Hickok NRC Technical Training Center Mr. Carey Fleming, Esquire 5700 Brainerd Road Sr. Counsel - Nuclear Generation Chattanooga, TN 37411-4017 Constellation Energy Nuclear Group, LLC 750 East Pratt Street, 17th floor Mr. Louis S. Larragoite Baltimore, MD 21202 Manager - Nuclear Licensing Constellation Energy Nuclear Generation Mr. Jay S. Gaines Group Director, Licensing 111 Market Place, 2nd Floor Calvert Cliffs Nuclear Power Plant Baltimore, MD 21202 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702 Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 287 St. Leonard, MD 20685 Ms. Susan T. Gray, Program Manager Power Plant Assessment Program Maryland Department of Natural Resources Tawes State Office Building B-3 580 Taylor Avenue Annapolis, MD 21401

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REACTOR VESSEL SURVEILLANCE CAPSULE WITHDRAWAL SCHEDULE REVISION CALVERT CLIFFS NUCLEAR POWER PLANT, INC.

CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50-317

1.0 INTRODUCTION

By letter dated March 5, 2008 (Agencywide Documents Access Management Systems Accession No. ML080660110), Calvert Cliffs Nuclear Power Plant, Inc. submitted for staff review a request for revising the withdrawal schedule for the reactor pressure vessel (RPV) surveillance capsule at the 104° location for Calvert Cliffs Nuclear Power Plant (CCNPP), Unit No. 1. The purpose of the licensees submittal was to provide an RPV surveillance capsule withdrawal schedule for CCNPP, Unit No. 1, that is consistent with the recently projected 60-year end-of-license (EOL) fluence at one-quarter of the RPV wall thickness (1/4T).

2.0 REGULATORY REQUIREMENTS The surveillance program for CCNPP, Unit No. 1, was implemented to monitor the radiation-induced changes in the mechanical and impact properties of the RPV materials. The surveillance program was established in accordance with Appendix H to Title 10 of the Code of Federal Regulations Part 50 (10 CFR Part 50), Reactor Vessel Material Surveillance Program Requirements. Appendix H to 10 CFR Part 50 requires licensees to monitor changes in the fracture toughness properties of ferritic materials in the RPV beltline region of light water nuclear power reactors. Appendix H to 10 CFR Part 50 states that the design of the surveillance program and the withdrawal schedule must meet the requirements of the edition of the American Society for Testing and Materials (ASTM) Standard E185, Standard Practice for Conducting Surveillance Tests for Light-Water Cooled Nuclear Power Reactor Vessels, that is current on the issue date of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) to which the reactor vessel was purchased. Later editions of ASTM E185 may be used including those editions through 1982 (ASTM E 185-82).

The RPV surveillance program for CCNPP, Unit No. 1, was initially established per ASTM E 185-70, which was the edition of the ASTM standard that was current on the issue date of the ASME Code to which the CCNPP, Unit No. 1 RPV was designed. However, its current surveillance capsule withdrawal schedule has been developed in accordance with ASTM E 185-82.

Enclosure

3.0 TECHNICAL EVALUATION

The licensees RPV surveillance program for CCNPP, Unit No. 1, is in accordance with the ASTM E185-82 standard and has a five-capsule withdrawal schedule (the sixth capsule is considered standby). This surveillance program, which was approved on November 8, 2000, was revised to satisfy the commitments stated in the NRC Safety Evaluation Report Related to the License Renewal of Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (NUREG-1705) for properly monitoring changes in the fracture toughness properties of RPV beltline materials during the extended period of operation. Currently, the first two capsules have been withdrawn and analyzed. The third capsule, the capsule at the 104° location, was scheduled to be withdrawn during the CCNPP, Unit No. 1 spring 2008 refueling outage. This schedule was based on the projected 60-year EOL 1/4T fluence of 2.96 X 1019 n/cm2 (E > 1.0 MeV) and the same projected fluence in 2008 for the third capsule. As reported in the submittal, these projected values have been revised to 3.06 X 1019 n/cm2 (E > 1.0 MeV) for the 60-year EOL 1/4T fluence and 3.12 X 1019 n/cm2 (E > 1.0 MeV) for the 2010 capsule fluence. Based on this, the licensee proposed to withdraw the third capsule during the units spring 2010 refueling outage.

ASTM E185-82 recommends that in a five capsule surveillance program the third capsule be withdrawn and tested at the time when the accumulated neutron fluence of the capsule corresponds to approximately the EOL 1/4T fluence. As discussed above, it is evident that the newly projected 2010 fluence for the third capsule is closer to the EOL 1/4T fluence than the previously projected fluence for the third capsule in 2008. Therefore, the NRC staff determined that withdrawing the third capsule during the units spring 2010 refueling outage meets the ASTM E185-82 recommendation for the third capsule.

Table 2 of the submittal showed that the withdrawal schedule for all other capsules (Capsules 4, 5, and standby) remained unchanged. This is reasonable considering the minor change in the projected 60-year EOL 1/4T fluence. Based on this, the staff determined that Capsules 4 and 5 still meet the ASTM E185-82 recommendation and the NUREG-1705 commitments. When better fluence predictions become available after the Capsule 3 data are analyzed, the licensee will perform additional evaluations to adjust, if necessary, the remaining capsule withdrawal schedules in accordance with 10 CFR Part 50, Appendix H, as stated in the submittal.

4.0 CONCLUSION

Based on the NRC staffs review of the submittal, the staff found that the revised withdrawal schedule for CCNPP, Unit No. 1, RPV satisfy the requirements of ASTM E185-82 and Appendix H to 10 CFR Part 50. In addition, the staff found that the revised withdrawal schedules for CCNPP still fulfills the commitment associated with Item 69 in Appendix E of NUREG-1705 for the renewed license period of 60 years. Therefore, the staff concludes that the licensees modified withdrawal schedule for CCNPP, Unit No. 1 is acceptable.

Principal Contributor: S. Sheng Date: April 9, 2008