ML020610003

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Request for Additional Information Residual Heat Removal Service Water System and Ultimate Heat Sink Technical Specifications Modifications (TAC Nos. MB2119 and MB2120)
ML020610003
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 03/19/2002
From: Colburn T
NRC/NRR/DLPM/LPD1
To: Byram R
Susquehanna
Colburn T, NRR/DLPM, 415-1402
References
TAC MB2119, TAC MB2120
Download: ML020610003 (7)


Text

March 19, 2002 Mr. Robert G. Byram Senior Vice President and Chief Nuclear Officer PPL Susquehanna, LLC 2 North Ninth Street Allentown, PA 18101

SUBJECT:

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION RE: RESIDUAL HEAT REMOVAL SERVICE WATER SYSTEM AND ULTIMATE HEAT SINK TECHNICAL SPECIFICATIONS MODIFICATIONS (TAC NOS. MB2119 AND MB2120)

Dear Mr. Byram:

By letter dated June 1, 2001, PPL Susquehanna, LLC (the licensee), proposed an amendment to modify the Susquehanna Steam Electric Station, Units 1 and 2, Technical Specifications Surveillance Requirement 3.7.1 to add operability and surveillance requirements for the ultimate heat sink spray bypass valves and large array valves. The proposed changes also reduce the allowed completion times for the conditions applicable to the residual heat removal service water system. The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensees request and has determined that additional information is required in order to complete our review. The additional information required is described in the enclosure.

This information request has been discussed with members of your staff and they have indicated that you would provide your response to the enclosed request within 45 days from the date of receipt. You also requested a meeting to discuss your response with the NRC staff prior to your formal submittal. We request you contact us to facilitate that meeting.

If you have any questions regarding this correspondence, please contact me at (301) 415-1402.

Sincerely,

/RA/

Timothy G. Colburn, Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388

Enclosure:

Request for Additional Information cc w/encl: See next page

Susquehanna Steam Electric Station, Units 1 &2 Bryan A. Snapp, Esq Herbert D. Woodeshick Assoc. General Counsel Special Office of the President PPL Services Corporation PPL Susquehanna, LLC 2 North Ninth Street GENTW3 Rural Route 1, Box 1797 Allentown, PA 18101-1179 Berwick, PA 18603-0035 Rocco R. Sgarro George T. Jones Supervisor-Nuclear Licensing Vice President-Nuclear PPL Susquehanna, LLC Engineering & Support 2 North Ninth Street GENA61 PPL Susquehanna, LLC Allentown, PA 18101-1179 2 North Ninth Street, GENA61 Allentown, PA 18101-1179 Senior Resident Inspector U.S. Nuclear Regulatory Commission Dr. Judith Johnsrud P.O. Box 35, NUCSA4 National Energy Committee Berwick, PA 18603-0035 Sierra Club 443 Orlando Avenue Director-Bureau of Radiation Protection State College, PA 16803 Pennsylvania Department of Environmental Protection Board of Supervisors P.O. Box 8469 Salem Township Harrisburg, PA 17105-8469 P.O. Box 405 Berwick, PA 18603-0035 PPL Susquehanna, LLC Nuclear Records Allen M. Male Attn: G. DallaPalu Manager - Quality Assurance 2 North Ninth Street GENA62 PPL Susquehanna, LLC Allentown, PA 18101-1179 Two North Ninth Street, GENA92 Allentown, PA 18101-1179 Richard W. Osborne Allegheny Electric Cooperative, Inc. Terry L. Harpster 212 Locust Street Manager - Nuclear Regulatory Affairs P.O. Box 1266 PPL Susquehanna, LLC Harrisburg, PA 17108-1266 Two North Ninth Street, GENA61 Allentown, PA 18101-1179 Regional Administrator, Region 1 U.S. Nuclear Regulatory Commission Richard L. Anderson 475 Allendale Road General Manager - SSES King of Prussia, PA 19406 Susquehanna Steam Electric Station PPL Susquehanna, LLC Bryce L. Shriver Box 467, NUCSB3 Vice President-Nuclear Site Operations Berwick, PA 18603-0035 Susquehanna Steam Electric Station PPL Susquehanna, LLC Ronald L. Ceravolo Box 467, NUCSA4 General Manager - Plant Support Berwick, PA 18603-0035 Susquehanna Steam Electric Station PPL Susquehanna Steam Electric Station Box 467, NUCSA4 Berwick, PA 18603-0035

REQUEST FOR ADDITIONAL INFORMATION RELATED TO REQUEST FOR RESIDUAL HEAT REMOVAL SERVICE WATER SYSTEM AND ULTIMATE HEAT SINK TECHNICAL SPECIFICATION MODIFICATIONS PPL SUSQUEHANNA, LLC ALLEGHENY ELECTRIC COOPERATIVE, INC.

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 DOCKET NOS. 50-387 AND 50-388

1. The description of the residual heat removal service water (RHRSW) subsystems provided on page 2 of Attachment 1 to your application does not match the simplified schematic provided in Figure 1 of Attachment 1, nor the apparent arrangement in P&ID M-112 for the RHRSW system. The description states that each subsystem contains a return header along with other components. However, the drawings and schematic indicate that there is only one return header per loop. Please clarify.
2. On P&ID M-112 for the RHRSW system, what water is being returned at coordinates E-9 and G-9?
3. The Nuclear Regulatory Commission (NRC) staff Safety Evaluation Report (SER),

NUREG-0776, Supplement 4, noted that the design of the emergency service water (ESW) system was modified to prevent water hammer in the event of an automatic pump start by changing the normal position of the spray bypass valves to closed. How has the water hammer issue been addressed considering that the current design has returned the normal position of this valve to open?

4. Please provide additional information regarding why the current application is explicitly removing the small spray bypass arrays from the Technical Specifications (TSs). As you note, each small array is subject to the same single failure (of a spray array bypass valve) that can make the same divisions large spray array inoperable. Appendix A to your application indicates that you considered adding a 30-day limiting condition for operation (LCO) for the small spray array valves, and determined that such an LCO posed an undue risk of a dual-unit shutdown with no increase in overall safety.
a. As described in your application, it appears that PPL Susquehanna, LLC, has reanalyzed the ultimate heat sink (UHS) for Susquehanna Steam Electric Station (SSES), Units 1 and 2, such that there are three 100-percent spray arrays for design-basis accident conditions; two large arrays and the combination of the two small arrays. The NRC staff SER, NUREG-0776, dated April 1981, indicates that the original analysis of the spray pond, and independent NRC staff analysis of the UHS Enclosure

design were performed assuming a single failure such that one spray pond cooling loop (one division/spray network, including both the large and the small arrays in the division) was available. Please provide further details of the analysis (or provide the analysis) which demonstrate the adequacy of the spray pond using only one large spray array. Also, please provide the details of the design-basis calculations which address the statement that the RHRSW/UHS requirements bound the ESW return path and UHS spray capacity requirement as discussed in the proposed Bases, Insert I to your application.

b. Address whether the current analysis considered both thermal efficiency (maintain temperature of pond below design) and maximum water loss due to drift, etc., for the 30-day duration. These two aspects were discussed as based on a separate analysis in NUREG-0776. Specifically, address the effect of using only a single large spray; which will increase spray nozzle differential pressure that was analyzed and confirmed by spray pond testing during initial licensing.
c. If the small arrays were credited in some scenarios with other degraded or inoperable components, then it would appear that less severe allowed outage times would be more appropriate than those in certain LCOs proposed in the TSs. For example, in Table 1 of Attachment 1 to the application, the condition with two large spray arrays out of service indicates that this condition represents an inoperable UHS and would require entry into TS 3.0.3 for both units. If both small arrays were operable under these conditions, then the plant would have full UHS capacity for design-basis conditions (as stated in your application), yet be required to follow a TS action requiring simultaneous shutdown of both units. Other proposed LCOs (e.g. 3.7.1.A) with 8-hour completion times based on insufficient RHRSW capacity remaining with a large spray array valve inoperable would appear to be justified for a 72-hour completion time with the availability of both small spray arrays.
5. The application states that the UHS analysis did not specifically address valve leakage; however, the flow values used for the RHRSW and ESW systems contain considerable margin from the actual flow values obtained from flow balances. Please provide the flow values used in the analysis and those typically obtained from flow balances.
6. In your application, you propose adding TS Surveillance Requirement (SR) 3.7.1.4 to verify that the spray loop bypass valves close upon receipt of a closing signal. Why is the automatic opening of these valves not similarly being added to the TSs? As stated in your application, these valves receive such a signal to ensure an adequate path exists for avoiding dead-headed conditions upon automatic starting of an associated RHRSW or ESW pump. Also, in this context, provide additional information explaining the proposed SR 3.7.1.4 Bases statement that The failure of the spray bypass valve to open on demand is not limiting and, therefore, would not cause the loop to be inoperable.
7. As proposed in your application for the condition of one inoperable Unit 1 RHRSW subsystem, TS 3.7.1.B appears to be missing a completion time requirement of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> from the discovery of both Unit 2 RHRSW systems inoperable (similar omission for Unit 2 TSs). Please address omission of this completion time which is discussed in your application and as one of the matrix completion times provided in Table 1 of Attachment 1

to the application (the similar Unit 2 requirement would be expected in proposed TS 3.7.1.C and subject to an 8-hour completion time).

8. Clarify the 8-hour completion time associated with proposed TS 3.7.1.A. For example, if one of the loop B valves in TS Table 3.7.1-1 is inoperable, thereby placing both Units in LCO 3.7.1, and the Unit 1 loop A RHRSW subsystem is subsequently discovered to be inoperable, are both Units 1 and 2 actions required to be complete within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />?
9. The proposed Unit 2 Bases, Insert G of the application, appears to be improperly formulated (not appropriately revised from the Unit 1 Bases, Insert G). Please provide the appropriate change.
10. Actions Note 2 proposed in your application for separate condition entry is unclear. The NRC staff recommends individual notes, as needed, in Actions A and B. Notes are not needed for Actions C and D. Action A is on a valve or loop basis and Action B is on an RHRSW subsystem basis.

March 19, 2002 Mr. Robert G. Byram Senior Vice President and Chief Nuclear Officer PPL Susquehanna, LLC 2 North Ninth Street Allentown, PA 18101

SUBJECT:

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION RE: RESIDUAL HEAT REMOVAL SERVICE WATER SYSTEM AND ULTIMATE HEAT SINK TECHNICAL SPECIFICATIONS MODIFICATIONS (TAC NOS. MB2119 AND MB2120)

Dear Mr. Byram:

By letter dated June 1, 2001, PPL Susquehanna, LLC (the licensee), proposed an amendment to modify the Susquehanna Steam Electric Station, Units 1 and 2, Technical Specifications Surveillance Requirement 3.7.1 to add operability and surveillance requirements for the ultimate heat sink spray bypass valves and large array valves. The proposed changes also reduce the allowed completion times for the conditions applicable to the residual heat removal service water system. The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensees request and has determined that additional information is required in order to complete our review. The additional information required is described in the enclosure.

This information request has been discussed with members of your staff and they have indicated that you would provide your response to the enclosed request within 45 days from the date of receipt. You also requested a meeting to discuss your response with the NRC staff prior to your formal submittal. We request you contact us to facilitate that meeting.

If you have any questions regarding this correspondence, please contact me at (301) 415-1402.

Sincerely,

/RA/

Timothy G. Colburn, Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388

Enclosure:

Request for Additional Information cc w/encl: See next page DISTRIBUTION PUBLIC MO'Brien OGC BPlatchek, RI PDI-1 Reading TTate ACRS BThomas EAdensam TColburn RArchizel JMunday MShanbaky, RI RDennig ACCESSION NO. ML020610003 NRR-088 OFFICE PDI-1/PM PDI-2/LA RORP/TSS SPLB(A)SC PDI-1/(A)SC NAME TColburn MO'Brien RDennig BThomas JMunday DATE 03/12/02 03/12/02 03/13/02 03/12/02 03/13/02 OFFICIAL RECORD COPY