ML20133B719

Forwards Response to RAI Re Third ten-yr Interval Inservice Insp Program.Revised ISI Rept Encl

ML20133B719
Person / Time
Site:	Cooper
Issue date:	12/31/1996
From:	Graham P NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20133B722	List: ML20133B719 ML20133B728
References
NLS960234, TAC-M94000, NUDOCS 9701060111
Download: ML20133B719 (6)

Text

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-W NLS960234 December 31,1996 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001

Subject:

Response to Request for Additional Information Regarding the Third 10-Year Interval Inservice Inspection Program (TAC No. M94000)

Cooper Nuclear Station, NRC Docket 50-298, DPR-46

References:

1. Letter to NRC Document Control Desk from J. H. Mueller dated October 18,1995, " Submittal of Third 10-year Interval Inservice Inspection Program"

2. Letter to NRC Document Control Desk from J. H. Mueller dated April 11, 1996," Submittal of Revision 1 to the Third 10-year Interval Inservice  ;

Inspection Program"

3. Letter to G. R. Horn (NPPD) from J. R. IIall (USNRC) dated October 24, 1996," Request for Additional Information Regarding Third 10-year Interval Inservice Inspection (ISI) Program" Gentlemen:

The purpose of this letter is to provide the additional information regarding the Third 10-year Interval Inservice Inspection (ISI) Program (submitted per References 1 and 2) for Cooper Nuclear Station, that was requested in your letter of October 24,1996 (Reference 3). The response to your questions is provided as Attachment I to this letter. Revised pages for the ISI Program are provided as Attachment 2.

If you have any questions or require any additional infonnation, please contact me.

Sincerely, pza,, u x Philip D. Graham l

Vice President - Nuclear Ah$7;,

/dnm Attachment 030044 9701060111 961231 PDR ADOCK 05000298 G PDR ~

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l NLS960234 December 31,1996

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cc: Regional Administrator USNRC - Region IV l

l Senior Project Manager USNRC - NRR Project Directorate IV-1 Senior Resident Inspector

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Michael T. Anderson l- INEL Research Center 1

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Attachment I to NLS960234 Page 1 of 3 ATTACHMENT 1 REQUEST FOR ADDITIONAL INFORMATION NRC Request A.a.

in Request for Relief RI-14, Nebraska Public Power District has requested to implement the alternative to Code requirements contained in Code Case N-509, Alternative Rulesfor the Selection and Examination ofClass 1, 2, and 3 Integrally Welded Attachments. The NRC staff's position is that this alternative to the Code requirements is acceptable for use with the following condition: that the licensee perform a minimum 10% sample examination of all integrally welded attachments for each Examination Category item in each Code class per interval.

NPPD Response NPPD will comply with the staff's position on Code Case N-509. Request for Relief RI-14 has been revised to reflect this additional condition. ,

i NRC Request A.h.

In Request for Relief PR-05, Nebraska public Power District has requested to implement the alternative to Code requirements contained in Code Case N-522, Pressure Testing of Containment Penetration Piping. The NRC staff's position is that the use of Code Case N-522 is acceptable with the following conditions: the test is conducted at the peak l calculated containment pressure, and the test procedure permits the detection and location of through-wall leakage in containment isolation valves and pipe segments between the '

CIVs.

NPPD Response The leakage test will be conducted at the peak calculated containment pressure. If the i leakage rate exceeds the Appendix J acceptance criteria, NPPD will apply additional measures in order to verify that the test failure is not due to a through-wall leak. These additional measures would be outside the scope of the leak rate test procedure. Request for Relief PR-05 has been revised to reflect these additional conditions.

NRC Request A.c.

In Request for Relief RI-02, Nebraska Public Power District requested authorization to continue using existing calibration blocks. For ti e existing calibration blocks, the licensee has committed to perform a comparison between the attenuation of the calibration block material and the material being examined when the block lacks appropriate documentation. The staff's position is that the proposed alternative must also include the performance of material velocity checks of the calibration blocks in conjunction with the attenuation checks. This will ensure that the ultrasonic scanning angle in the materials is essentially the same.

4 Attachment I to NLS960234 Page 2 of 3 NPPD Response NPPD will comply with the staff's position on performing velocity checks in conjunction with attenuation checks. Request for Relief RI-02 has been revised to reflect this additional condition.

NRC Request B.

a.) In the licensee's response to the staff's questions regarding Request for Relief PR-4 02, the licensee stated the pressure test boundaries are essentially equivalent to the Code required pressure boundaries. Provide a list of the portions of all Class 1 pressure test boundaries excluded from the system leakage and hydrostatic tests.

Describe how the pressure test requirements will be satisfied for those remaining sections of piping beyond the proposed boundaries.

b.) Describe how the proposed alternative will provide the same level of quality and safety for the pressure test boundaries defined by the Code.

c.) Describe how a test pressure associated with 100% reactor pressure will be achieved.

NPPD Response Section XI states that the boundary for the system leakage test shall be the reactor coolant pressure boundary with all valves in the position required during reactor startup. In a PWR the primary loop is a closed system. This is not the case in a BWR. The purpose of Request for Relief PR-02 is to clarify that certain Class 1 boundary valves which are normally open for reactor startup, will be closed for the pressure test.

a.) Three of the four Feedwater Check valves will be closed for the system pressure test following a refueling outage. The inboard check on one Feedwater line is kept open by Reactor Water Cleanup (RWCU) flow. The RWCU system is kept in service during the pressure tests. During the ten-year hydrostatic pressure test, a mechanical jumper will be installed around the other inboard check valve to pressurize the syctem to the outboard check valve. The outboard check valves are the class 1 boundary valves.

The four outboard Main Steam Isolation Valves (MSIV) will be closed for the system pressure test and the ten-year hydrostatic pressure test. The inboard MSIV's are opened to pressurize the system to the outboard valves. The outboard MSIV's are the class 1 boundary valves.

6 Both liigh Pressure Coolant Injection (IIPCI) and both Reactor Core Isolation Cooling (RCIC) steam supply valves will be closed for the system pressure test following a refueling outage. These valves close automatically on low steam

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i Attachment 1 to NLS960234 I Page 3 of 3 supply pressure. During the ten-year hydrostatic pressure test, the system will be pressurized to the outboard valves. The outboard valves are the class 1 boundary valves.

b.) The position of the valves for the system leakage test and the hydrostatic pressure j test as described above is consistent with the intent of footnote 1 to Table IWB- 1 2500-1, Category B-P. Abnormal lineups and installation ofjumpers is not required for the system leakage test. For example, both the inboard and outboard class 1 isolation valves in the Core Spray system are in their nomial closed position for the system leakage test. The inboard check valves arejumpered during the ten-year hydrostatic pressure test. Although the inboard check valves are closed for the system leakage test, the VT-2 inspection includes the outboard 4

valves. The valves described in (a) above are normally open during a reactor startup. In order to pressurize the reactor coolant pressure boundary for testing, these valves must be closed. ,

Since the portions of the piping between the valves described in (a) above are operated at or above reactor pressure during normal operation, any through wall i

leakage would be detected by the drywell leakage collection system, or by operations perronnel on normal rounds.

c.) Except as described in (a) above, the Class 1 boundary is pressurized as required by the Code. The VT-2 inspection includes the entire reactor coolant pressure boundary.

4 We regret any confusion this Request for Relief may have caused.

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ATTACHMENT 3 LIST OF 24RC COMMITMENTS l

l Correspondence No: NLS960234 i

The following table identifies those actions committed to by the District in this  !

document. Any other actions discussed in the submittal represent intended or planned actions by the District. They are described to the NRC for the NRC's informat. ion and are not regulatory commitments. Please notify the Licensing Manager l at Cooper Nuclear Station of any questions regarding this document or any associated  ;

regulatorf commitments.

COMMITTED DATE l COMMITMENT OR OUTAGE I None N/A i

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l PROCEDURE NUMBER 0.42 l REVISION NUMBER 1.2 l PAGE 8 OF 10 l-

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