ML032300333
| ML032300333 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 08/25/2003 |
| From: | Milano P NRC/NRR/DLPM/LPD1 |
| To: | Kansler M Entergy Nuclear Operations |
| Milano P, NRR/DLPM 415-1457 | |
| References | |
| GL-96-006, TAC M96822, TAC M96823 | |
| Download: ML032300333 (7) | |
Text
August 25, 2003 Mr. Michael R. Kansler, President Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601
SUBJECT:
CLOSEOUT OF RESPONSES TO GENERIC LETTER 96-06, INDIAN POINT NUCLEAR GENERATING UNIT NOS. 2 AND 3 (TAC NOS. M96822 AND M96823)
Dear Mr. Kansler:
On September 30, 1996, the U.S. Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 96-06, Assurance of Equipment Operability and Containment Integrity During Design-Basis Accident Conditions. In the GL, the NRC staff requested licensees to determine: (1) if containment air cooler cooling water systems are susceptible to either water-hammer or two-phase flow conditions during postulated accident conditions, and (2) if piping systems that penetrate the containment are susceptible to thermal expansion of fluid so that over-pressurization of piping could occur.
In letters dated October 30, 1996, January 28, April 30, August 29, and November 21, 1997, September 15, 1998, and September 12, 2000, Consolidated Edison Company of New York, Inc. (Con Edison, the former licensee), provided its response to GL 96-06 for Indian Point Nuclear Generating Unit No. 2 (IP2). In letters dated October 30, 1996, January 28, March 3, and October 14, 1997, and October 23, 1998, the New York Power Authority (NYPA, the former licensee) provided its response for Indian Point Nuclear Generating Unit No. 3 (IP3). Entergy Nuclear Operations, Inc. (Entergy, the current licensee for IP2 and 3), provided additional information in a letter dated July 30, 2002, as supplemented on January 31, 2003.
Water-hammer or Two-Phase Flow Cooling water systems serving the containment air coolers may be exposed to the hydrodynamic effects of water-hammer during either a loss-of-coolant accident (LOCA) or a main steamline break. In addition, cooling water systems serving the containment air coolers may experience two-phase flow conditions during design-basis accident scenarios whereas the heat removal assumptions were based on single-phase flow conditions. Therefore, cooling water systems may need corrective actions to satisfy system design and operability requirements. In GL 96-06, the NRC requested licensees to evaluate cooling water systems that serve containment air coolers to assure that they are not vulnerable to water-hammer and two-phase flow conditions.
Subsequent to issuance of GL 96-06, the Electric Power Research Institute (EPRI) developed an analytical methodology for evaluating the GL 96-06 water-hammer issue that was documented in EPRI Technical Reports 1003098 and 1006456 (previously known as EPRI Report TR-113594), and approved by the NRC in an evaluation dated April 3, 2002 (included as Appendix A to EPRI Technical Report 1003098). Section 3.3 of the staffs evaluation requested that licensees who chose to use the EPRI methodology provide additional information to
M. Kansler confirm that the methodology was applicable for their specific application and that it was being applied properly, and to justify any proposed exceptions. Entergy provided the additional information that was requested in the staffs evaluation of the EPRI methodology in a letter dated July 30, 2002, as supplemented by letter dated January 31, 2003.
In the case of IP2, the licensees analysis demonstrated that the affected plant piping, components, and supports were acceptable and satisfied the applicable stress criteria. In the case of IP3, the licensee determined that modifications were required for ten supports in order to assure that design-basis margins are maintained during water-hammer events. The necessary support modifications have been completed and no additional actions are required.
As a point of clarification, in a telephone conversation on May 8, 2003, the licensee indicated that the licensing basis load combinations (water-hammer loads together with other loads) were used for evaluating the structural integrity of the service water piping. Based on its review of the information that was submitted along with the clarification that was provided, the NRC staff considers Entergys evaluation of the GL 96-06 water-hammer issue to be consistent with the EPRI methodology as approved by the staff and finds the licensees response and corrective actions to address the GL 96-06 water-hammer issue to be acceptable. With regard to the two-phase flow issue, the staff is satisfied with the licensees responses dated January 28, 1997, and September 15, 1998, (for IP2); and January 28, 1997, and October 23, 1998 (for IP3).
Although satisfied with the licensees response for the water-hammer and two-phase flow elements of GL 96-06, the NRC staff has not performed a detailed review of the licensees water-hammer analysis or of the modifications that were made to the supports on IP3.
Therefore, this could be the subject of a future NRC audit or inspection activity.
Based on the above, the staff concludes that the licensees response adequately addresses the water-hammer and two-phase flow concerns identified in GL 96-06 for IP2 and 3.
Thermally-Induced Over-Pressurization Thermally-induced over-pressurization of isolated water-filled piping sections in containment could jeopardize the ability of accident-mitigating systems to perform their safety functions and could also lead to a breach of containment integrity via bypass leakage. Corrective actions may be needed to satisfy system operability requirements.
- a.
IP2 In its January 28, 1997, letter, Con Edison identified nine penetrations potentially vulnerable to a water-solid volume that may be subjected to an increase in pressure due to heating of the trapped fluid. The affected lines are: (1) two primary water lines, (2) two boric acid water lines, (3) four segments of sampling system, and (4) one instrument line. Con Edison determined that six lines were operable based on the criteria in Appendix F of Section III of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) and that three lines were operable based on valve lift and capacity for relieving system pressure. Con Edison determined that the relief of system pressure will occur below the pressure at which pipe stresses would exceed the allowable stresses described in the Updated Final Safety Analysis Report (UFSAR). In its April 30, 1997, letter, Con Edison reviewed the effects of a postulated single failure of the relief valve (stuck-open relief valve) on lines that are susceptible to thermal
M. Kansler over-pressurization and identified no failure modes which would adversely affect the ability of safety-systems to perform their intended functions during design-basis accident conditions.
In the November 21, 1997, letter, Con Edison responded to an NRC request for additional information dated September 22, 1997, by stating that for long-term corrective action, it had cut, drained, and capped the instrument line, installed relief valves on two boric acid water lines and two sampling lines, and installed new pipe insulation on one of the primary water lines during the 1997 refueling outage. Con Edison also stated that it had re-evaluated two of the sampling lines and determined that the lines would remain within the UFSAR design-basis stress limits.
For the remaining line which relies on an air-operated diaphragm valve to open to provide system pressure relief, Con Edison provided valve drawings, the calculations to determine the valve lift pressure, and the uncertainty associated with the calculated lift pressure.
The NRC staff finds Con Edisons evaluation to be acceptable. Therefore, the staff concludes that the response adequately addresses the thermally induced over-pressurization concern identified in GL 96-06 for IP2.
- b.
IP3 In its January 28, 1997, letter, NYPA identified 16 penetrations that were potentially vulnerable to a water-solid volume. NYPA determined that ten of the lines were operable based on the criteria in Appendix F of Section III of the ASME Code and that five of the lines were operable based on valve lift for relieving system pressure. NYPA also determined that the system pressure relief would occur below the pressure at which pipe stresses would exceed the allowable stresses in the IP3 FSAR. For the remaining lines, NYPA revised its administrative procedure to ensure that the fluid is drained during normal plant operation to preclude potential over-pressurization during design-basis accident conditions.
In its October 14, 1997, letter, NYPA responded to an NRC request for additional information dated September 16, 1997, by stating that based upon its further review, only 13 penetrations were potentially susceptible to over-pressurization resulting from either, or both, the LOCA conditions in containment and high-energy line break conditions in the primary auxiliary building (PAB). In its evaluation, NYPA determined that six of the lines meet the design-basis stress limits and that the lines contain air-operated diaphragm valves that would open to self-relieve pressure prior to exceeding ASME Code design limits or FSAR faulted-condition stress limits.
NYPA provided a summary description of the analytical methodology, assumptions, and acceptance criteria utilized for the evaluation of piping segments and valves. In its evaluation, NYPA stated that isolation of the steam generator blowdown line break would occur before Phase A containment isolation in the piping penetration area. Also, by limiting the mass and energy release to the PAB, early isolation of the ruptured steam generator blowdown line would limit the temperature in the piping penetration area.
The NRC staff finds NYPAs evaluation to be acceptable. Thus, the staff concludes that the response adequately addresses the thermally-induced over-pressurization concern identified in GL 96-06 for IP3.
M. Kansler If you should have any questions, please contact me. This completes the NRC staffs actions regarding GL 96-06 for IP2 and 3, under TAC Nos. M96822 and M96823.
Sincerely,
/RA/
Patrick D. Milano, Sr. Project Manager,Section I Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-247 and 50-286 cc: See next page
M. Kansler If you should have any questions, please contact me. This completes the NRC staffs actions regarding GL 96-06 for IP2 and 3, under TAC Nos. M96822 and M96823.
Sincerely,
/RA/
Patrick D. Milano, Sr. Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-247 and 50-286 cc: See next page DISTRIBUTION:
PUBLIC PD I-1 R/F C. Holden W. Bateman E. Imbro R. Laufer D. Solorio K. Manoly P. Milano L. Raghavan S. Little J. Tatum C. Hammer B. Platchek, R-I P. Eselgroth, R-I OGC ACRS
- See previous concurrence ACCESSION NO. ML032300333
- Concur with corrections as noted OFFICE PDI-1/PM PDI-1/LA SPLB/SC*
EMEB/SC PDI-1/SC NAME PMilano SLittle DSolorio KManoly **
RLaufer DATE 08/22/03 08/22/03 08/07/03 08/18/03 08/25/03 OFFICIAL RECORD COPY
Indian Point Nuclear Generating Unit Nos. 2 & 3 cc:
Mr. Gary Taylor Chief Executive Officer Entergy Operations, Inc.
1340 Echelon Parkway Jackson, MS 39213 Mr. John Herron Senior Vice President and Chief Operating Officer Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Mr. Fred Dacimo Vice President, Operations Entergy Nuclear Operations, Inc.
Indian Point Energy Center 295 Broadway, Suite 2 P.O. Box 249 Buchanan, NY 10511-0249 Mr. Christopher Schwarz General Manager, Plant Operations Entergy Nuclear Operations, Inc.
Indian Point Energy Center 295 Broadway, Suite 2 P.O. Box 249 Buchanan, NY 10511-0249 Mr. Dan Pace Vice President Engineering Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Mr. Randall Edington Vice President Operations Support Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Mr. John Kelly Director, Nuclear Safety Assurance Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Ms. Charlene Faison Manager, Licensing Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Director of Oversight Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Mr. James Comiotes Director, Nuclear Safety Assurance Entergy Nuclear Operations, Inc.
Indian Point Energy Center 295 Broadway, Suite 2 P.O. Box 249 Buchanan, NY 10511-0249 Mr. John McCann Manager, Licensing Entergy Nuclear Operations, Inc.
Indian Point Energy Center 295 Broadway, Suite 2 P. O. Box 249 Buchanan, NY 10511-0249 Mr. John M. Fulton Assistant General Counsel Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Senior Resident Inspector, Indian Point 2 U. S. Nuclear Regulatory Commission 295 Broadway, Suite 1 P.O. Box 38 Buchanan, NY 10511-0038
Indian Point Nuclear Generating Unit Nos. 2 & 3 cc:
Senior Resident Inspector, Indian Point 3 U. S. Nuclear Regulatory Commission 295 Broadway, Suite 1 P.O. Box 337 Buchanan, NY 10511-0337 Mr. Peter R. Smith, Acting President New York State Energy, Research, and Development Authority Corporate Plaza West 286 Washington Avenue Extension Albany, NY 12203-6399 Mr. J. Spath, Program Director New York State Energy, Research, and Development Authority 17 Columbia Circle Albany, NY 12203-6399 Mr. Paul Eddy Electric Division New York State Department of Public Service 3 Empire State Plaza, 10th Floor Albany, NY 12223 Mr. Charles Donaldson, Esquire Assistant Attorney General New York Department of Law 120 Broadway New York, NY 10271 Mayor, Village of Buchanan 236 Tate Avenue Buchanan, NY 10511 Mr. Ray Albanese Executive Chair Four County Nuclear Safety Committee Westchester County Fire Training Center 4 Dana Road Valhalla, NY 10592 Ms. Stacey Lousteau Treasury Department Entergy Services, Inc.
639 Loyola Avenue Mail Stop: L-ENT-15E New Orleans, LA 70113 Mr. William DiProfio PWR SRC ConsultaNT 139 Depot Road East Kingston, NH 03827 Mr. Dan C. Poole PWR SRC Consultant 20 Captains Cove Road Inglis, FL 34449 Mr. William T. Russell PWR SRC Consultant 400 Plantation Lane Stevensville, MD 21666-3232 Alex Matthiessen Executive Director Riverkeeper, Inc.
25 Wing & Wing Garrison, NY 10524 Paul Leventhal The Nuclear Control Institute 1000 Connecticut Avenue NW Suite 410 Washington, DC, 20036 Karl Copeland Pace Environmental Litigation Clinic 78 No. Broadway White Plains, NY 10603 Jim Riccio Greenpeace 702 H Street, NW Suite 300 Washington, DC 20001