ML082340922
ML082340922 | |
Person / Time | |
---|---|
Site: | Salem ![]() |
Issue date: | 09/24/2008 |
From: | Richard Ennis Plant Licensing Branch 1 |
To: | Levis W Public Service Enterprise Group |
Ennis R, NRR/DORL, 415-1420 | |
Shared Package | |
ml082340910 | List: |
References | |
TAC MD8259, TAC MD8260 | |
Download: ML082340922 (18) | |
Text
September 24, 2008 Mr. William Levis President and Chief Nuclear Officer PSEG Nuclear LLC 80 Park Plaza, T4B Newark, NJ 07101
SUBJECT:
SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1 AND 2, ISSUANCE OF AMENDMENTS RE: REFUELING OPERATIONS - DECAY TIME (TAC NOS. MD8259 AND MD8260)
Dear Mr. Levis:
The Commission has issued the enclosed Amendment Nos. 289 and 273 to Facility Operating License Nos. DPR-70 and DPR-75 for the Salem Nuclear Generating Station (Salem), Unit Nos. 1 and 2. These amendments consist of changes to the Technical Specifications (TSs) in response to your application dated March 11, 2008, as supplemented by letters dated June 17, and July 23, 2008. The amendments revise the TS requirements for fuel decay time prior to commencing movement of irradiated fuel in the reactor pressure vessel.
A copy of our safety evaluation is also enclosed. Notice of Issuance will be included in the Commission's biweekly Federal Register notice.
Sincerely,
/ra/
Richard B. Ennis, Senior Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-272 and 50-311
Enclosures:
- 1. Amendment No. 289 to License No. DPR-70
- 2. Amendment No. 273 to License No. DPR-75
- 3. Safety Evaluation cc w/encls: See next page
September 24, 2008 Mr. William Levis President and Chief Nuclear Officer PSEG Nuclear LLC 80 Park Plaza, T4B Newark, NJ 07101
SUBJECT:
SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1 AND 2, ISSUANCE OF AMENDMENTS RE: REFUELING OPERATIONS - DECAY TIME (TAC NOS. MD8259 AND MD8260)
Dear Mr. Levis:
The Commission has issued the enclosed Amendment Nos. 289 and 273 to Facility Operating License Nos. DPR-70 and DPR-75 for the Salem Nuclear Generating Station (Salem), Unit Nos. 1 and 2. These amendments consist of changes to the Technical Specifications (TSs) in response to your application dated March 11, 2008, as supplemented by letters dated June 17, and July 23, 2008. The amendments revise the TS requirements for fuel decay time prior to commencing movement of irradiated fuel in the reactor pressure vessel.
A copy of our safety evaluation is also enclosed. Notice of Issuance will be included in the Commission's biweekly Federal Register notice.
Sincerely,
/ra/
Richard B. Ennis, Senior Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-272 and 50-311
Enclosures:
- 1. Amendment No. 289 to License No. DPR-70
- 2. Amendment No. 273 to License No. DPR-75
- 3. Safety Evaluation cc w/encls: See next page DISTRIBUTION:
PUBLIC RidsOgcRp Resource LPL1-2 R/F RidsAcrsAcnwMailCTR Resource RidsNrrDorlLpl1-2 Resource RidsNrrDirsltsb Resource RidsNrrLAABaxter Resource RidsRgn1MailCenter Resource RidsNrrPMREnnis Resource GHill (2), OIS RidsNrrDorlDPR Resource SJones, NRR/SBPB Package Accession No.: ML082340910 Amendment Accession No: ML082340922 TS Accession Nos.: ML082340975 (Unit 1); ML082340996 (Unit 2) *SE dated 9/12/08 OFFICE LPL1-2/PM LPL1-2/LA AADB/BC SBPB/BC (A)* OGC LPL1-2/BC NAME REnnis ABaxter RTaylor MRahimi DRoth HChernoff DATE 9/16/08 9/16/08 9/18/08 9/12/08 9/23/08 9/24/08 OFFICIAL RECORD COPY
Salem Nuclear Generating Station, Unit Nos. 1 and 2 cc:
Mr. Thomas Joyce Senior Resident Inspector Senior Vice President - Operations Salem Nuclear Generating Station PSEG Nuclear U.S. Nuclear Regulatory Commission P.O. Box 236, N09 Drawer 0509 Hancocks Bridge, NJ 08038 Hancocks Bridge, NJ 08038 Mr. Robert Braun Mr. Kevin Chambliss Site Vice President - Salem Director - Nuclear Oversight PSEG Nuclear PSEG Nuclear P.O. Box 236, S05 P.O. Box 236, X16 Hancocks Bridge, NJ 08038 Hancocks Bridge, NJ 08038 Mr. Carl Fricker Mr. William Mattingly Vice President - Operations Support Manager - Salem Regulatory Assurance PSEG Nuclear PSEG Nuclear P.O. Box 236, X15 P.O. Box 236, S05 Hancocks Bridge, NJ 08038 Hancocks Bridge, NJ 08038 Mr. George Gellrich Mr. William Levis Plant Manager - Salem President and Chief Nuclear Officer PSEG Nuclear 80 Park Plaza, T4B P.O. Box 236, S05 Newark, NJ 07101 Hancocks Bridge, NJ 08038 Mr. Jeff Keenan, Esquire Manager - Licensing PSEG Nuclear - N21 P.O. Box 236 Hancocks Bridge, NJ 08038 Township Clerk Lower Alloways Creek Township Municipal Building, P.O. Box 157 Hancocks Bridge, NJ 08038 Mr. Paul Bauldauf, P.E., Asst. Director Radiation Protection Programs NJ Department of Environmental Protection and Energy CN 415 Trenton, NJ 08625-0415 Mr. Brian Beam Board of Public Utilities 2 Gateway Center, Tenth Floor Newark, NJ 07102 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406
PSEG NUCLEAR LLC EXELON GENERATION COMPANY, LLC DOCKET NO. 50-272 SALEM NUCLEAR GENERATING STATION, UNIT NO. 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 289 License No. DPR-70
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment filed by PSEG Nuclear LLC, acting on behalf of itself and Exelon Generation Company, LLC (the licensees) dated March 11, 2008, as supplemented by letters dated June 17, and July 23, 2008, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in Title 10 of the Code of Federal Regulations (10 CFR), Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. DPR-70 is hereby amended to read as follows:
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 289, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.
- 3. This license amendment is effective as of its date of issuance and shall be implemented within 30 days.
FOR THE NUCLEAR REGULATORY COMMISSION
/ra/
Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Facility Operating License and the Technical Specifications Date of Issuance: September 24, 2008
ATTACHMENT TO LICENSE AMENDMENT NO. 289 FACILITY OPERATING LICENSE NO. DPR-70 DOCKET NO. 50-272 Replace the following page of Facility Operating License No. DPR-70 with the attached revised page as indicated. The revised page is identified by amendment number and contains a marginal line indicating the area of change.
Remove Insert Page 4 Page 4 Replace the following page of the Appendix A, Technical Specifications, with the attached revised page as indicated. The revised page is identified by amendment number and contains marginal lines indicating the areas of change.
Remove Insert 3/4 9-3 3/4 9-3
PSEG NUCLEAR LLC EXELON GENERATION COMPANY, LLC DOCKET NO. 50-311 SALEM NUCLEAR GENERATING STATION, UNIT NO. 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 273 License No. DPR-75
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment filed by PSEG Nuclear LLC, acting on behalf of itself and Exelon Generation Company, LLC (the licensees) dated March 11, 2008, as supplemented by letters dated June 17, and July 23, 2008, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in Title 10 of the Code of Federal Regulations (10 CFR), Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. DPR-75 is hereby amended to read as follows:
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 273, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.
- 3. This license amendment is effective as of its date of issuance and shall be implemented within 30 days.
FOR THE NUCLEAR REGULATORY COMMISSION
/ra/
Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Facility Operating License and the Technical Specifications Date of Issuance: September 24, 2008
ATTACHMENT TO LICENSE AMENDMENT NO. 273 FACILITY OPERATING LICENSE NO. DPR-75 DOCKET NO. 50-311 Replace the following page of Facility Operating License No. DPR-75 with the attached revised page as indicated. The revised page is identified by amendment number and contains a marginal line indicating the area of change.
Remove Insert Page 4 Page 4 Replace the following page of the Appendix A, Technical Specifications, with the attached revised page as indicated. The revised page is identified by amendment number and contains marginal lines indicating the areas of change.
Remove Insert 3/4 9-3 3/4 9-3
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS. 289 AND 273 TO FACILITY OPERATING LICENSE NOS. DPR-70 AND DPR-75 PSEG NUCLEAR LLC EXELON GENERATION COMPANY, LLC SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-272 AND 50-311
1.0 INTRODUCTION
By application dated March 11, 2008, as supplemented by letters dated June 17, and July 23, 2008, (Agencywide Documents Access and Management System (ADAMS) Accession Nos.
ML080930080, ML081790153, and ML082110417, respectively ), PSEG Nuclear LLC (PSEG or the licensee) submitted an amendment request for Salem Nuclear Generating Station (Salem),
Unit Nos. 1 and 2. The proposed amendment would revise the requirements for fuel decay time prior to commencing movement of irradiated fuel in the reactor pressure vessel (RPV).
Currently, Technical Specification (TS) 3/4.9.3, Decay Time, requires that: (a) the reactor has been subcritical for at least 100 hour0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />s1 prior to movement of irradiated fuel in the RPV between October 15th through May 15th; and (b) the reactor has been subcritical for at least 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> prior to movement of irradiated fuel in the RPV between May 16th and October 14th. The calendar approach is based on average river water temperature which is cooler in the fall through spring months. The proposed amendment would allow fuel movement to commence at 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> after the reactor is subcritical between October 15th through May 15th. During the period from May 16th and October 14th, the existing decay time requirement of 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> would still apply.
The supplements dated June 17, and July 23, 2008, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the Nuclear Regulatory Commission (NRC or the Commission) staff=s original proposed 1 The current TS decay time requirement of 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> is applicable through the year 2010. Without a change to the current TSs, after 2010, the 168 hour0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> decay time requirement would be applicable for th th refueling outages occurring between October 15 and May 15 . On March 5, 2008, the NRC approved a one-time change for Salem Unit No.2 (Amendment No. 271) which revised TS 3/4.9.3 to allow fuel movement to commence at 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br /> after the reactor is subcritical for refueling outage 2R16 (spring 2008 outage). The proposed amendment would change the 100 hour0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> requirement to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> and would delete year 2010 applicability.
Enclosure
no significant hazards consideration determination as published in the Federal Register on July 15, 2008 (73 FR 40631).
2.0 REGULATORY EVALUATION
The licensee addressed the regulatory requirements applicable to the proposed amendment in Section 5.2 of Attachment 1 to the application dated March 11, 2008. The regulatory requirements, criteria, and guidance which the NRC staff applied in its review are discussed below.
As discussed in Section 3.1 of the Salem Updated Final Safety Analysis Report (UFSAR), the general design criteria (GDC) followed in the design of Salem Units 1 and 2 are the Atomic Industrial Forum version, as published in a letter to the Atomic Energy Commission from E. A. Wiggin, Atomic Industrial Forum, dated October 2, 1967. Section 3.1.3 of the UFSAR also states that the Salem Unit 1 and 2 design also conforms with the intent of Appendix A to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, General Design Criteria for Nuclear Power Plants, dated July 7, 1971, except for several specific exceptions as noted in that UFSAR section. The following GDCs in Appendix A to 10 CFR Part 50 are applicable to the proposed amendment:
! GDC 19, Control room, insofar as it specifies that adequate radiation protection is provided to permit access and occupancy of the control room under accident conditions.
! GDC 61, Fuel storage and handling radioactivity control, insofar as it specifies that fuel storage systems shall be designed with: (1) a residual heat removal system capability having reliability and testability that reflects the importance to safety of decay heat and other residual heat removal; and (2) the capability to prevent a significant reduction in fuel storage coolant inventory under accident conditions.
UFSAR Section 15.4.6 describes the current Salem licensing basis analysis for a fuel handling accident (FHA). The current analysis uses a fuel decay time of 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> which bounds the current minimum decay time of 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> required by TS 3.9.3. The licensees current analysis for an FHA is based on selective use of an alternative source term (AST) in accordance with 10 CFR 50.67, Accident source term, and the guidance in Regulatory Guide (RG) 1.183, Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors. The selective implementation of the AST methodology for an FHA was approved by the NRC for Salem Units 1 and 2 in Amendment Nos. 251 and 232 on October 10, 2002 (ADAMS Accession No. ML022770181). Full scope implementation of the AST methodology for Salem Units 1 and 2 was approved by the NRC in Amendment Nos. 271 and 252 on February 17, 2006 (ADAMS Accession No. ML060040322).
Salem has two separate and independent spent fuel pools (SFPs), with one pool associated with each operating reactor. The proposed amendment involves a change in the minimum decay time from 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> for fuel removed from the reactor during the period from October 15th to May 15th, which increases the maximum decay heat generation that could be placed within the SFPs for refueling during that period. Under otherwise identical conditions, a larger decay heat generation rate leads to a higher peak SFP temperature with the cooling systems in operation and a greater rate of temperature increase if the cooling system fails.
Decay heat is removed from each SFP by the spent fuel cooling system. Each spent fuel cooling system consists of one seismically qualified cooling train, which includes two full-capacity pumps and one heat exchanger. The pumps are supplied power from the vital electrical distribution system, which is backed by an emergency diesel generator. In the event one cooling system fails, the remaining system can be periodically swapped between the two SFPs to provide intermittent cooling to both pools. Heat is removed from the spent fuel cooling system heat exchangers by the safety-related component cooling water (CCW) system, which is cooled by the safety-related service water (SW) system.
Section 9.1.3 of the UFSAR describes that the spent fuel cooling system provides cooling to remove residual heat from the fuel stored in the SFP, specifies temperature limits for the SFP under certain conditions, and specifies measures to ensure those temperature limits would not be exceeded. The system is designed with reliability and redundancy to assure continued heat removal under normal, abnormal, and accident conditions. The SFP temperature limits are:
149 °F when both heat exchangers are available and 180 °F when only one spent fuel cooling system heat exchanger is available to cool both pools. The SFP structure, including the liner, has been evaluated by the licensee for performance of its design function at a temperature of 180 °F. As described in UFSAR Section 9.1.3, Salems Integrated Decay Heat Management (IDHM) Program specifies that a pre-outage assessment of the SFP pool heat loads and heatup rates be performed to assure availability of adequate SFP cooling capability prior to offloading fuel. The procedural controls included in the IDHM Program require that, prior to each refueling, the following steps are taken:
(1) Calculate that the SFP water temperature will not exceed 149 °F following full core offload, using one heat exchanger for each SFP, and provide the required CCW temperature to achieve such results to the Salem Operations staff.
(2) Calculate that the SFP water temperature will not exceed 180 °F following full core offload, using one heat exchanger for both SFPs, and provide the required CCW temperature to achieve such results to the Salem Operations staff.
(3) Prior to initiating core offload activities, validate the assumptions used in the IDHM Program calculations. The validation includes ensuring the availability of both SFP heat exchangers and verifying that the actual CCW temperatures are consistent with the IDHM calculation input values.
3.0 TECHNICAL EVALUATION
Before movement of any irradiated fuel from the RPV to the SFP, a period of in-vessel decay is required. This is because of post design-basis accident radiation dose consequence limitations and fuel pool cooling capacity requirements. With regard to pool cooling, decay heat from irradiated fuel assemblies decreases as the fission products that dominate heat generation decay. Also, due to radioactive decay, the amount of radioactivity available for release from the fuel is reduced over time. Therefore, the longer the fuel elements are allowed to decay within the RPV before being moved, the less heat is transferred to the SFP, and the lower the dose consequence of a radioactive release resulting from an FHA.
The current Salem licensing basis includes an 100-hour decay time requirement for outage periods falling between October 15th and May 15th and an 168-hour decay time requirement for outage periods falling between May 16th and October 14th. The 100-hour decay time requirement was included in TS 3.9.3 via Amendment Nos. 251 and 232 which were issued by the NRC on October 10, 2002. These amendments represented a change from the previous year-round decay time requirement of 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />.
In a previous, and now withdrawn, amendment request dated August 4, 2006, the licensee proposed a change that would have allowed the movement of irradiated fuel in the RPV to commence at 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after shutdown or at a decay time calculated using the licensees IDHM program, whichever is later.
In an application dated October 17, 2007, the licensee proposed a one-time revision to the decay time requirements in TS 3.9.3 (from 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> to 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br />) applicable only for the Salem Unit No. 2 spring 2008 refueling outage. The NRC staff approved this request in Salem Unit No. 2 Amendment No. 271 dated March 5, 2008. To support the one-time TS 3.9.3 change to use a fuel decay time of 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br />, the licensee re-analyzed the radiological consequences of a design-basis FHA using a bounding minimum decay time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
For this current amendment request, the licensee proposes to change the decay time requirements in TS 3.9.3, for outage periods falling between October 15th and May 15th, from 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> for both Salem Unit Nos. 1 and 2.
The NRC staffs technical evaluation of the proposed amendment is organized as follows:
3.1 FHA Radiological Consequences 3.2 SFP Cooling 3.3 Technical Evaluation Conclusion 3.1 FHA Radiological Consequences As discussed in Section 3.0 of this safety evaluation (SE), to support the one-time TS 3.9.3 change to use a fuel decay time of 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br /> for the Salem Unit No. 2 spring 2008 refueling outage, the licensee re-analyzed the radiological consequences of a design-basis FHA using a bounding minimum decay time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The licensees detailed FHA radiological consequences analysis using the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> decay time (Calculation S-C-ZZ-MDC-1920, revision 4IR0) was provided in Attachment 5 to its application dated October 17, 2007 (ADAMS Accession No. ML073470363).
As discussed in its SE for Salem Unit No. 2 Amendment No. 271 dated March 5, 2008 (ADAMS Accession No. ML080320421), the NRC staff evaluated the impact of the 24-hour decay time, assumed in calculation S-C-ZZ-MDC-1920, on the previously analyzed radiological consequences for an FHA, discussed in UFSAR Section 15.4.6, and the acceptability of the revised analysis results. Consistent with 10 CFR 50.67, GDC 19, and Regulatory Position C.4.4 in RG 1.183, the applicable acceptance criteria for an FHA are 5 roentgen equivalent man (rem) total effective dose equivalent (TEDE) in the control room, 6.3 rem TEDE at the exclusion area boundary (EAB), and 6.3 rem TEDE at the outer boundary of the low population zone (LPZ).
Section 3.1.2 of the NRC staffs SE for Salem Unit No. 2 Amendment No. 271 concluded the following:
As described above, the NRC staff reviewed the assumptions, inputs, and methods used by the licensee to assess the radiological impact of implementing the proposed changes to the Salem Unit 2 TSs. The NRC staff finds that the licensee used analysis methods and assumptions consistent with the conservative regulatory requirements and guidance identified in Section 2.0 above. The NRC staff compared the doses estimated by the licensee to the applicable acceptance criteria identified in SE Section 2.0. In all cases, the calculated doses were below the applicable acceptance criteria. Based on the above findings, the NRC staff concludes that there is reasonable assurance that, in the event of a design-basis FHA following implementation of the proposed amendment, the EAB, LPZ, and control room doses would be below the applicable acceptance criteria. Therefore, the NRC staff concludes that the proposed amendment is acceptable with respect to radiological consequences.
The current amendment request proposes to change the decay time requirements in TS 3.9.3, for outage periods falling between October 15th and May 15th, from 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> for both Salem Unit Nos. 1 and 2. With respect to radiological consequences, and as noted in PSEGs application dated March 11, 2008, the proposed amendment is based on the identical calculation that supported Salem Unit 2 Amendment No. 271 (i.e., calculation S-C-ZZ-MDC-1920, revision 4IR0). The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> decay time assumed in the calculation conservatively bounds the proposed TS decay time of 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. As such, the NRCs staffs previous evaluation of the radiological consequences for an FHA for Salem Unit No. 2 Amendment No. 271 is applicable to the proposed amendment for Salem Unit Nos. 1 and 2. Therefore, the proposed amendment is acceptable with respect to radiological consequences.
3.2 SFP Cooling The proposed change to TS 3.9.3, which reduces the minimum decay time from 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> during the period from October 15th through May 15th, will result in the potential for increased decay heat loads within the SFP. In its license amendment request, PSEG described an evaluation of SFP cooling capability and administrative controls implemented through Salems IDHM Program to assure spent fuel temperature limits are maintained. This program specifies that a pre-outage assessment of the SFP heat loads and heatup rates be performed to assure availability of adequate SFP cooling capability prior to offloading fuel. As an attachment to its letter dated March 11, 2008, PSEG provided Calculation S-C-SF-MDC-1810, Revision 8, Decay Heat-up Rates and Curves," for Salem Unit 1 Refueling Outage 1R19. This calculation included an appendix providing an analysis of heat loads and peak SFP temperatures based on an inventory of fuel that fills each of the SFPs to its licensed capacity. This inventory consists of actual refueling discharges prior to the date of the amendment request, estimated discharges from future refueling outages, and a future full core offload that results in each of the SFPs being filled to its licensed capacity.
Calculation S-C-SF-MDC-1810 evaluated the SFP peak temperature by analysis using the licensees computer program, CROSSTIE. In the NRC SE for Amendments 251 and 232 for Salem Units 1 and 2, respectively, the NRC staff accepted the use of CROSSTIE in the IDHM
Program to provide an accurate representation of peak SFP temperature. The analyses used the following assumptions:
(1) A full core offload begins at the proposed minimum decay time of 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> and is completed 41 hours4.74537e-4 days <br />0.0114 hours <br />6.779101e-5 weeks <br />1.56005e-5 months <br /> later.
(2) Decay heat (background heat in SFP plus offloaded core) is calculated based on the methodology given in NRC Branch Technical Position ASB 9-2. The calculated decay heat is based on actual fuel assembly inventory and burnup. For the full SFP heat load condition, the analysis assumes the pools are filled to the current licensed storage capacity by a future full core offload and future projected refueling batches occurring at 18-month intervals, with refueling beginning either October 15th or April 15th.
(3) Credit is taken for heat loss to the Fuel Handling Building (FHB) atmosphere. The FHB ambient temperature is conservatively assumed to be 110 °F. The design value is 105 °F, which bounds the maximum calculated temperature based on the design SFP temperature of 180 °F. The FHB relative humidity is conservatively assumed to be 100%.
(4) The net SFP water volume is based on the minimum TS SFP level of 23 feet above the fuel assemblies (TS 3.9.11) and a fully offloaded core.
Using the above methods and assumptions, the licensee evaluated the following conditions:
(1) Normal cooling where each units SFP is aligned to its spent fuel cooling heat exchanger (SFCHX). This case determines the peak SFP temperature as a function of CCW temperature and the CCW temperature that results in a peak SFP temperature of 149 °F. The licensee determined a corresponding maximum SW temperature and compared it to the historical maximum for the associated time of year. For this case, the licensee assumed that the outage SFP is aligned to a single SFCHX. It also assumes that only one CCW heat exchanger is aligned, which lowers the maximum allowable SW temperature.
(2) Cross-connect operation where the SFPs for each unit are swapped between a single SFCHX, with the other Units SFCHX unavailable (in the unlikely event that an SFCHX becomes unavailable post core off-load). This case determines the time available to swap cooling between the SFPs prior to the uncooled SFP reaching the design limit of 180 °F. For this case, the licensee conservatively assumed that a loss of cooling to one SFP occurs 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> after core offload is complete, with maximum decay heat load in the outage (Unit 2) SFP.
For the normal cooling conditions, the licensee determined that a CCW temperature of 80 °F results in a peak Unit 1 SFP temperature for 1R19 of 142.7 °F. Similarly, under normal refueling conditions for representative fuel inventories (including a full core offload) that fill the refueling units SFP, the licensee determined that a CCW temperature of 80 °F results in a peak Unit 1 SFP temperature of 143.4 °F and a peak Unit 2 SFP temperature of 143.7 °F. Under typical refueling conditions, the licensee stated that this CCW temperature correlates to a maximum SW temperature of 71 °F.
The licensee determined that the historical maximum SW temperature for mid-October is approximately 70 °F, and that temperature is the highest historical maximum temperature for the entire period from October 15th through May 15th. Consequently the SW temperature for future refueling outages during the period from October 15th through May 15th will likely be bounded by the 71 °F SW temperature used in the above analyses. Thus, for decay times of 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />, the expected available cooling capacity is adequate to maintain a substantial margin between actual SFP temperature and the SFP temperature limit of 149 °F.
For cross-connect operations during the Unit 1 outage 1R19, the licensee determined that both SFPs can be maintained below the licensing basis limit of 180 °F with a single available SFCHX.
With the outage unit (Unit 1) SFP aligned to be cooled by the available SFCHX, the licensee determined that the isolated Unit 2 peak SFP temperature would reach the licensing basis limit of 180 °F. Thus, swapping of SFPs between the available SFCHX would be necessary to maintain both SFPs below 180 °F. For loss of forced cooling to the outage (Unit 1) SFP, the licensee determined that the minimum time to reach the licensing basis SFP temperature limit of 180 °F would be 2.6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> from SFP conditions expected 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> after the end of the offload with a CCW temperature of 80 °F. For loss of forced cooling to the non-outage (Unit 2) SFP at a CCW temperature of 80 °F, the licensee determined that, once the non-outage (Unit 2) SFP reaches the licensing basis SFP temperature limit of 180 °F, at least 5.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> would be available to align the available SFCHX to cool the Unit 2 SFP and then realign the available SFCHX to the outage (Unit 1) SFP.
The licensee validated through walkdowns that realignment of a spent fuel cooling system loop to the alternate pool requires less than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The licensee stated that procedures direct resetting of the SFP high temperature alarm for SFP temperatures above the normal set point of 125 °F to maintain effective indication of a loss of cooling. Therefore, in the unlikely event of a loss of cooling to the Unit 2 SFP near the completion of the offload, adequate time would be available to identify the loss of cooling and realign cooling from the Unit 1 SFP to the Unit 2 SFP before the Unit 2 SFP temperature exceeds the licensing basis temperature limit of 180 °F. The licensee also evaluated the potential repeated swapping of spent fuel cooling between pools to maintain both SFPs below 170 °F and determined that adequate time to realign cooling would be available for this more restrictive control of peak SFP temperature.
The licensee presented validation data from previous refueling outages at SFP temperatures ranging from 66 °F to approximately 120 °F. This information confirmed the accuracy of the CROSSTIE program at temperatures where evaporative cooling from the SFP is unimportant.
However, the NRC staff questioned the accuracy of the program in modeling heat transfer to the fuel handling building when evaporative cooling is important, such as scenarios involving loss of forced cooling. To address this issue, the licensee presented sensitivity analyses demonstrating that the SFP heat-up projections from the CROSSTIE model were relatively insensitive to FHB temperatures between 105 °F and 120 °F.
After reviewing these projections, the NRC staff requested that the licensee address uncertainties in the CROSSTIE model. Specifically, the staff requested that the licensee discuss the quality of the modeling used to predict SFP temperature response, the reliability of the fuel building ventilation system at high SFP temperatures, and the reliability of the operators completing repeated transfers of a single cooling train between SFPs following the design-basis loss of a single heat exchanger. In the supplement dated July 23, 2008, the licensee identified
conservatisms in the model and other factors that provide margin to overcome uncertainties.
Assuming a CCW temperature of 80 °F, the CROSSTIE predicts a margin of over 5 °F to the 149 °F SFP temperature limit under normal cooling conditions and a margin of over 2.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> to the minimum 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> time to realign an SFCHX to the alternate SFP. The licensee also provided results of a sensitivity study where the effects of evaporative cooling were effectively removed from the model. These results indicated that substantial margin to the acceptance limits would be maintained in the event evaporative cooling was ineffective.
Based on a search of correlations and data for evaporative cooling described in Attachment 2 to the supplement dated July 23, 2008, the licensee concluded that the CROSSTIE model slightly over-predicts evaporative cooling, and the licensee entered the issue in its corrective action program. Nevertheless, the NRC staff agreed that the model results provide sufficient margin to assure that the SFP temperature can be maintained within specified limits. Therefore, although the CROSSTIE model of evaporative cooling is not validated at high SFP temperatures, the methodology and assumptions are adequate to provide reasonable estimates of the time for pool temperature to increase to specific values. The available margin in time to reestablish cooling following loss of forced cooling and the additional margin provided by the expected low SW temperatures provide reasonable assurance that the licensing basis SFP temperature limits will be maintained in the unlikely event of a loss of forced cooling to either SFP.
The NRC staff also questioned the lack of a bounding calculation of SFP temperatures for future offloads. The licensee explained that implementation of the IDHM program provides assurance that the SFP temperatures for future refueling outages would remain within limits. The results of the CROSSTIE model for future projected SFP inventories indicates that substantial margin would be maintained for future refueling outages with decay times of 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. This margin results from the expected low SW temperatures during the period from October 15th through May 15th and the insignificant increase in decay heat resulting from additional operating cycles.
The provisions of the IDHM program described in Section 9.1.3 of the Salem UFSAR ensure that the required cooling capability would be available for future refueling outages, regardless of changes to the inventory of the SFPs.
Based on its review, the NRC staff concludes that the proposed change to TS 3.9.3, in conjunction with the operational controls on CCW temperature specified by the IDHM program; provide reasonable assurance that the decay heat removal capability will be maintained consistent with its importance to safety. Also, the SFP cooling system provides the capability to prevent a significant reduction in coolant inventory under accident conditions. The proposed change in minimum decay time to 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> for future refueling outages is acceptable because:
(1) the SFP cooling system will be capable of maintaining an appropriate pool temperature consistent with the current design basis during planned refueling evolutions; and, (2) with the failure of a single cooling train, the cooling system will maintain SFP temperature within analyzed limits for SFP structural integrity with the remaining cooling system in operation to cool both SFPs.
3.3 Technical Evaluation Conclusion The NRC staff concludes that the proposed changes to TS 3.9.3 to allow fuel movement to commence at 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br /> after the reactor is subcritical between October 15th through May 15th is acceptable based on the discussion in SE Sections 3.1 and 3.2.
The proposed amendment would also delete the following note in Salem Unit No. 2 TS 3.9.3:
- For Salem Unit 2 refueling outage 2R16 only, the required subcritical time is 86 hours9.953704e-4 days <br />0.0239 hours <br />1.421958e-4 weeks <br />3.2723e-5 months <br /> The above note was added as a one-time revision to the requirements for fuel decay time in Salem Unit No. 2 Amendment No. 271. The note was applicable only for the Salem Unit No. 2 spring 2008 refueling outage. Since this note is no longer applicable, the proposed deletion is administrative in nature, and therefore, is acceptable.
Based on the above, the NRC staff concludes that the proposed amendment is acceptable.
6.0 STATE CONSULTATION
In accordance with the Commission's regulations, the New Jersey State official was notified of the proposed issuance of the amendments. The State official had no comments.
7.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (73 FR 40631). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
8.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors: S. Jones R. Ennis Date: September 24, 2008