ML071020423
| ML071020423 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 04/29/2007 |
| From: | Catherine Haney Plant Licensing Branch III-2 |
| To: | Stall J Florida Power & Light Co |
| Mozafari B, NRR/ADRO/DORL, 415-2020 | |
| References | |
| TAC MD4192, TAC MD4193 | |
| Download: ML071020423 (4) | |
Text
April 29, 2007 Mr. J. A. Stall Senior Vice President Nuclear and Chief Nuclear Officer Florida Power and Light Company P.O. Box 14000 Juno Beach, FL 33408-0420
SUBJECT:
TURKEY POINT NUCLEAR PLANT, UNITS 3 AND 4 - PRESSURIZER SURGE, SPRAY, SAFETY, AND RELIEF NOZZLE WELD SUSCEPTIBILITY TO PRIMARY WATER STRESS CORROSION CRACKING (TAC NOS. MD4192 AND MD4193)
Dear Mr. Stall:
This letter acknowledges the receipt of information from Florida Power and Light Company (FPL or the licensee) pertaining to the pressurizer surge, spray, safety, and relief nozzle and safe end welds at Turkey Point Nuclear Plant, Units 3 and 4.
The discovery in October 2006 of five circumferential indications in three Alloy 82/182 dissimilar metal (DM) welds on the pressurizer at the Wolf Creek Generating Station (Wolf Creek) raised safety concerns based on the size and location of the indications. At Wolf Creek three indications were in the pressurizer surge nozzle-to-safe end weld and two separate indications were in the safety and relief nozzle-to-safe end welds. In addition, these findings indicated that significant concerns might exist with the inspection schedules for addressing the pressurizer weld concerns issued by the industry-sponsored Materials Reliability Program (MRP) contained in Primary System Piping Butt Weld Inspection and Evaluation Guideline (MRP-139).
The Nuclear Regulatory Commission (NRC) is concerned about the pressurizer surge nozzle-to-safe end weld indications, as this is the first time that multiple circumferential primary water stress-corrosion cracking (PWSCC) indications have been identified in a weld. This condition calls into question the degree of safety margin present in past structural integrity evaluations for flawed DM welds susceptible to PWSCC, since multiple stress-corrosion cracking flaws may grow independently and ultimately grow together, significantly reducing the time from flaw initiation to leakage or rupture.
Based on discussions with the NRC staff, licensees of plants susceptible to this condition have committed to an enhanced inspection frequency and reactor coolant system leakage monitoring until actions to mitigate the potential of PWSCC in the affected welds have been completed.
J. Stall In your letter dated January 31, 2007, you stated that the pressurizers at Turkey Point Nuclear Plant, Units 3 and 4, do not incorporate Alloy 82/182 butt welds. As a result, your response adequately addresses the NRC concerns at this time regarding PWSCC susceptibility of these welds.
This completes the NRC staffs efforts on TAC Nos. MD4192 and MD4193. If you have any questions, please contact Brenda Mozafari at (301) 415-2020.
Sincerely,
/RA/
Catherine Haney, Director Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-250 and 50-251 License Nos. DPR-31 and DPR-41 cc: See next page
ML071020423 OFFICE LPL2-2/PM LPL2-2/LA CPNB NAME BMozafari BClayton TLupold DATE 04/20/07 04/19/07 04/25/07 OFFICE LPL2-2/BC CPNB/BC DORL/D NAME TBoyce TChan CHaney DATE 4/24/07 4/25/07 4/29/07
Florida Power and Light Company TURKEY POINT PLANT cc:
Mr. William E. Webster Vice President, Nuclear Operations Florida Power & Light Company P.O. Box 14000 Juno Beach, FL 33408-0420 M. S. Ross, Managing Attorney Florida Power & Light Company P.O. Box 14000 Juno Beach, FL 33408-0420 Marjan Mashhadi, Senior Attorney Florida Power & Light Company 801 Pennsylvania Avenue, NW.
Suite 220 Washington, DC 20004 Terry O. Jones Site Vice President Turkey Point Nuclear Plant Florida Power and Light Company 9760 SW. 344th Street Florida City, FL 33035 County Manager Miami-Dade County 111 Northwest 1 Street, 29th Floor Miami, Florida 33128 Senior Resident Inspector Turkey Point Nuclear Plant U.S. Nuclear Regulatory Commission 9762 SW. 344th Street Florida City, Florida 33035 Mr. William A. Passetti, Chief Department of Health Bureau of Radiation Control 2020 Capital Circle, SE, Bin #C21 Tallahassee, Florida 32399-1741 Mr. Craig Fugate, Director Division of Emergency Preparedness Department of Community Affairs 2740 Centerview Drive Tallahassee, Florida 32399-2100 Attorney General Department of Legal Affairs The Capitol Tallahassee, Florida 32304 Michael O. Pearce Plant General Manager Turkey Point Nuclear Plant Florida Power and Light Company 9760 SW. 344th Street Florida City, FL 33035 James Connolly, Licensing Manager Florida Power and Light Company Turkey Point Nuclear Plant 9760 SW. 344th Street Florida City, FL 33035 Becky Ferrare Licensing Department Administrator Florida Power and Light Company Turkey Point Nuclear Plant 9760 SW. 344th Street Florida City, FL 33035 Mark Warner, Vice President Nuclear Operations Support Florida Power and Light Company P.O. Box 14000 Juno Beach, FL 33408-0420 Mr. Rajiv S. Kundalkar Vice President - Nuclear Engineering Florida Power & Light Company P.O. Box 14000 Juno Beach, FL 33408-0420