ML20198K496
| ML20198K496 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 01/09/1998 |
| From: | Graham P NEBRASKA PUBLIC POWER DISTRICT |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NLS980003, NUDOCS 9801150015 | |
| Download: ML20198K496 (4) | |
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NLS980003 January 9,1998 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
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Gentlemen:
Subject:
Third 10-Year interval inservice Inspection Program; Relief Request PR-10 Cooper Nuclear Station, NRC Docket 50-298, DPR-46
Reference:
Letter (No. NLS960234) to U.S. NRC Document Control Desk from Phillip D.
Graham (NPPD) dated December 31,1996," Response to Request for Additional Information Regarding the Third 10-Year Interval inservice Inspection Program" The pinose of this letter is to submit Relief Request PR-10 for Nuclear Regulatory Commission (NRC) review and approval. Relief Request PR-10 is a new request and supplements information previously provided to the NRC concerning the Third 10-Year Interval inservice inspection Program for Cooper Nuclear Station (CNS) (the most recent submittal is referenced above). The District requests approval of the subject relief request by January 31,1998, in order to support the mid-cycle outage that is planned for March 1998, but could occur sooner.
Should you have any questions conceming this matter, please contact me.
Sincerely, Dh Philip D. Graham Vice President - Nuclear
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USNRC - Region IV USNRC Senior Project Manager NPG Distribution USNRC - NRR Project Directorate 4 ~ rn eg usooi
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Attachment to
.NI'S930003 Page 1 of 2 Cocper Station 3rd Interval Inservice Inspection Rogram RELIEF REQUEST NUMBER: PR-10, REVISION 0 COMPONENT IDENTIFICATION h
Code Classes:
1
References:
IWB-5211(a)
- 9. amination Categories:
B-P Item Numbers:
C7.40
==
Description:==
System leakage 1:st pressur:
[
Component Numbers:
MS-RV-71 ARV, MS-RV-71BRV, MS-RV-71CRV, MS-RV-
[
71DRV, MS-RV-71ERV, MS-RV-71FRV, MS-RV-71GRV, MS-RV-71HRV CODE REOUIREMENT e
IWB-5221(a) requires the system leakage test to be conducted at a pressure not less than the nominal operating pressure associatt..i with 100% rated reactor power.
HASIS FOR RELIEF During the 1995 mid-cycle outage, CNS will be replacing the pilot cartridge assemblies on the eight Main Steam safety relief valves. The pilot cartridge assemblies will have been set point tested and certified to OM-1 requirements prior to installetion. ASME XI requires an inservice leak test and a t'T-2 visual examination for these replacements. Because the pilot cartridge assemblies will have been set point tested, this pressure test focuses on the mechanical connection between the valve body and the pilot cartridge assembly. Since the safety relief valves are not isola'.ie f om the reactor vessel, the entire primary system will have to be pressurized in order to perform this test. A leakage test at a pressure not less than the nominal operating pressure associated with 100% rated reactor power (1005 psig) cannot be performed during a nonnal startup. This pressure is not reached until the reactor is into the power operatmg range. Radiation levels and temperatures would subject the examiners to adverse conditions. An alternate test method would require extensive une line ups and procedural controls in order to heat up and pressurize the entire primary system fcr an inservice leak test. This test usually takes two days of outage time and is normally perforr ed after a refueling outage. A nonnal st;.rtup occurs aner recovery from the inservice leak int procedure. During e normal start tp, VT-2 qualified Operators perform a walkdown of the containment at r.pproximately 500 and 900 psig.
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Attachment to
.NLS980003 Page 2 of 2 -
Cooper Station 3rd Interval Inservice Inspection Program Research by the ASME in support of Code Cases N-416-1 and N-498-1 has demonstrated that the leakage rates are proportional to the test pressure. Thus, a pressure test at 900 psig will identify leakage through the mechanical connection. Conducting n pressure test of the entire reacter coolant system boundary would be an economic burden (one to two days of critical path time) and subject the plant to increased risk from an infrequently performed test. Therefore, reliefis requested in accordance with 10 CFR 50.55a(a)(3)(ii). Compliance with the specified 6
requirements of tnis section would result in hardship or unusual ditriculty without a coinpensating increase in the level of quality and safety.
Pl;OPOSED ALTERNATE PROVISIONS in lieu of performing a Class 1 inservic' system pressure test on the Main Steam safety relief valve pilot cartridge assemblies at 1005 psig, CNS will perform a pressure test on these comp (ments at a minimum of 900 psig during the normal startup following their replacement.
Disposition of observed leakage will consider the marginal increase in leakage rates that would occur at the nominal operating pressure associated with 100% rated reactor powcr.
APPLICAHLE TIME PERIOD Reliefis reouested for the 1998 mid-cycle outage at CNS.
f. ATT5:'HMENT 3 LIST OF NRC COC4ITMENTS l
4 Correspondence Not NLS980003 The following table identifies those actions committed to by the District in this document. Any other actions discLJsed in the sGbf8ttal represent intended or planned actions by the District.
They are described to the NRC for the NRC's information and are not regulatory commitments.
Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITTED DATE COMMITMENT OR OUTAGE CNS will perform a pressure test on MS-RV-71ARV, MS-RV-71BRV, F.3-RV-71CRV, MS-RV-71DRV, MS-RV-71ERV, MS-RV-71FRV, MS-RV-71GRV, MS-RV-71HRV at a minimum of 900 psig 1998 Mid-Cycle Outage during the normal startup following their replacement.
Contingent upon NRC Disposition of observed leakage vill consider the y y marginal increase in leakage rates that would occur at the nominal operating nressure associated with 100% rated power.
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PROCEDURE NUMBER 0.42 l
REVISION NUMBER 5 l
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