ML20116M301

Provides Supplemental Info to Relief Requests Submitted in Ltr Dtd 960318,in Response to Matter Discussed W/Staff During Recent Telcon

ML20116M301
Person / Time
Site:	Nine Mile Point
Issue date:	08/08/1996
From:	Terry C NIAGARA MOHAWK POWER CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NMP2L-1650, NUDOCS 9608200107
Download: ML20116M301 (9)

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NIAGARA MOHAWK NINE MILE POINT NUCLEAR STATION 1AKE ROAD. P.O. BOX 63, LYCOMING, NEW YORK 13093/ TELEPHONE (315) 349-7263 G E N E R ATIO N BUSINESS GROUP August 8,1996 CARL D. TERRY NMP2L 1650 Vice President

, Nuclear Engineenng U. S. Nuclear Regulatory Commission Atta: Document Control Desk Washington, DC 20555 RE: Nine Mile Point Unit 2 Docket No. 50-410 NPF-69

Subject:

ReliefRequests Gentlemen:

This letter provides supplemental information to the six relief requests submitted in a letter dated March 18,1996 (NMP2L 1618). The supplemental information provided by this letter is in response to matters discussed with the Staff during recent telephone conferences.

Relief Request GVRR-1, Rev.1 is modified to reference subsection IWV-2200(a) in the

! discw.lon of the basis for relief. Also, with regards to this relief request, primary cor&hment isolation valves will be leak tested in accordance with Option B of Appendix J of 10 CFR 50 and Part 10 of ASME/ ANSI OMa-1988 Sections 4.2.2.2,4.2.2.3(e) and 4.2.2.3(f).

Relief Requests CPS-VRR-1, Rev.1; RCS-VRR-1, Rev.1; and GSN-VRR-1, Rev.1 are modified to state that reverse flow closure will be verified at least once per fuel cycle (i.e.,

every refueling outage). These three relief requests are also modified to eliminate references to 30 months.

l Relief Request CMS-PTRR-1, Rev. O for the Containment Monitoring System (CMS) is withdrawn since Niagara Mohawk has concluded that a previously approved relief request (i.e., RR-IWC-7, Rev.1) continues to remain valid. This conclusion is based on Niagara Mohawk's review of the Staff's Safety Evaluation dated October 16,1991, regarding Relief Request RR-IWC-7, Rev.1. Specifically, the technical basis of the Staff's Safety Evaluation and its conclusions which were arrived at when Nine Mile Point Unit 2 (NMP2) was in compliance with Option A of Appendix J continue to remain valid upon implementation of Option B of Appendix J.

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9608200107 960008 PDR P

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l Relief Request HCS-PTRR-1, Rev. O for the Hydrogen Recombiner System (HCS) has been  :

modified and is now consistent with Relief Request RR-IWC-7, Rev.1 for the CMS.

Specifically, both relief requests provide relief from IWA-5240. The basis for these relief ,

requests is also similar in that significant amounts of piping insulation are required to be l removed to perform visual examinations. Furthermore, a significant radwaste impact is realized with the disposal of leak detection fluid and wipes as well as the disposal ofinsulation ,

which becomes damaged during its removal and re-installation for the HCS and the CMS. In addition, the handling of piping insulation and the performance of visual examinations I constitute a hardship in maintaining radiological doses as low as reasonably achievable (ALARA) for both systems. The alternate examination requirements are also similar for these i relief requests in that the application of an Appendix J test method assures that the detection of leakage is maintained with the appropriate level of safety and quality. Accordingly, Relief-Request HCS-PTRR-1, Rev. O is very similar to Relief Request RR-IWC-7, Rev.1 (which was approved by the Staff). l Finally, with regards to the modified relief request for HCS and the approved relief request for l CMS, all American Society of Mechanical Engineers (ASME) Class 2 pressure retaining i boundary components are subject to periodic pressure tests at approximately every 40 months in accordance with Section XI of the ASME Code.

If additional information is needed with regards to these six relief requests, please contact 1 Kenneth Korcz (315-349-7222) of our Licensing staff. l Very truly yours, Y '

V"7 C. D. Terry Vice President - Nuclear Engineering Page 2 CDT/KWK/Imc Attachments  ;

xc: Regional Administrator, Region 1 Mr. B. S. Norris, Senior Resident Inspector j Mr. D. S. Hood, Senior Project Manager, NRR l Records Management

RELIEF REQUEST NO. GVRR-1, REVISION 1 Valves  : Containment Isolation Valves Category  : A Class  : 1,2 Testing Requirements  : I.eak rate test in accordance with Subsection IWV-3420 1 Basis for l Relief  : IWV-2200(a) defines " Category A" valves as " valves for which l seat leakage is limited to a specified maximum amount in the closed position for fulfillment of their function." Containment isolation valves have been identified as " Category A" valves for 4

ASME XI testing purposes since they are required to be leak rate tested. Leak rate requirements for these valves are based on valve specific allowable leakage rates.

The Technical Specifications also contain leakage / operability criteria for containment isolation valves. Specifically, those containment isolation valves with potential for bypass leakage paths outside containment have individual maximum allowable leak rates as defined in Table 3.6.1.2-1 of the Technical Specifications. In addition, excess flow check valves, per }

Surveillance Requirement 4.6.3.4, receive an operability test.  ;

I Since containment isolation valves are " Category A" valves, leakage rate testing requirements ofIWV-3420 must be ,

satisfied. The leakage rate testing performed per Option B of

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Appendix J of 10 CFR 50, satisfies the requirements ofIWV- l 3423 through 3426. However, it does not satisfy the corrective j actions required by IWV-3427. Therefore, the requirements of l IWV-3427(a) will be applied to individual leakage rate testing results obtained during (Option B of Appendix J of 10 CFR 50)

Technical Specification required surveillance testing. Consistent with NRC Generic Letter No. 89-04, the requirements of IWV-3427(b) will not be applied for Category "A" valves.

Alternate Testing  : Containment isolation valves which are categorized as " Category A or AC" valves shall be leak rate tested in accordance with Option B of Appendix J of 10 CFR 50. Individual valve leakage rates will be obtained by test or analysis and the i

. RELIEF REQUEST NO. GVRR-1, Revision 1 (Cont'd.)

requirements of IWV-3427(a) will be applied to these containment isolation valves. The test frequency will be in accordance with the performance-based requirements of Option B of Appendix J. Containment isolation valves that are exempted from Option B of Appendix J of 10 CFR 50 shall meet the test requirements as stated in the Inservice Testing Program.

i RELIEF REQUEST NO. CPS-VRR-1, Revision 1 l

l System  : Containment Purge System Valve (s)  : 2 CPS *V50,2 CPS *V51 Category  : A. C Class  : 2 l

Function  : Air supply to CPS *AOV107 and 2 CPS *AOV109 Inside Containment Isolation Valves Quarterly Test Requirement  : Verify reverse flow closure in accordance with IWV-3520 1 Basis for Relief  : These valves are located inside the suppression chamber. The only practical means to verify reverse flow closure of these valves is to apply pressure on the down stream side of the valve

! via a test connection located inside the suppression chamber. ,

j During normal operation and at cold shutdowns when access to l primary containment is not required, the suppression chamber is -

inerted with nitrogen, limiting access to emergency situations only. In addition, high radiation levels during power operations prohibit suppression chamber entry.

l The only safety function for these valves in the closed position is l containment isolation. Testing of containment isolation valves is governed by Option B of Appendix J of 10 CFR 50 which will verify closure and leak tightness on a test interval betwan 30 and l

60 months depending upon the as-found performance history of

the valve.

Alternate 1 Testing  : Reverse flow closure will be verified by performing Option B of Appendix J Type C testing on a nonperformance based test i- interval. Accordingly, reverse flow closure will be verified at least once per fuel cycle (i.e., every refueling outage).

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RELIEF REQUEST NO. RCS-VRR-1, Revision 1 System  : Reactor Coolant (recirculation)

Valve (s)  : 2RCS*V59A, B 2RCS*V60A, B 2RCS*V90A, B Category  : AC I I

Class  : 2 l

Function  : Reactor coolant recirculation pump seal water, primary containment isolation valves '

Quarter Test Requirement  : Verify reverse flow closure in accordance with IWV-3520  ;

I Basis for j Relief  : Verifying reverse flow closure would require stopping seal water flow to the pumps. The interruption of seal water flow, even for a short time, is an undesirable operational configuration. Due to system design, the only practical method available to verify reverse flow closure is by valve leak testing during Option B of Appendix J of 10 CFR 50 testing.

The only safety function for these valves in the closed position is containment isolation. Testing of containment isolation valves is governed by Option B of Appendix J of 10 CFR 50 which will verify closure and leak tightness on a test interval between 30 and 60 months depending upon the as-found performance history of the valve.

4 Alternate Testing  : Reverse flow closure will be verified by performing Option B of Appendix J Type C testing on a nonperformance based test interval. Accordingly, reverse flow closure will be verified at least once per fuel cycle (i.e., every refueling outage).

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RELIEF REQUEST NO. GSN-VRR-1, Revision 1 l

l System  : Nitrogen l

Valve (s)  : 2GSN*V170 l Category  : AC 1

l Class  : 2 l

Function  : TIP mechanism nitrogen purge primary containment isolation valves l

Quarterly Test Requirement  : Verify reverse flow closure in accordance with IWV-3520 Basis for Relief  : This valve and associated test connections are located in a very l highly contaminated region of the primary containment which  !

makes testing at cold shutdown impractical. The only practical method available to verify reverse flow closure is by valve leak rate testing during Option B of Appendix J of 10 CFR 50 Type C testing after the area has been decontaminated.

The only safety function for these valves in the closed position is containment isolation. Testing of containment isolation valves is j governed by Option B of Appendix J of 10 CFR 50 which will verify closure and leak tightness on a test interval between 30 and 60 months depending upon the as-found performance history of the valve.

Alternate Testing  : Reverse flow closure will be verified by performing Option B of Appendix J Type C testing on a nonperformance based test interval. Accordingly, reverse flow closure will be verified at ,

least once per fuel cycle (i.e., every refueling outage).

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RELIEF REQUEST NO. HCS-PTRR-1, Revision 0 Components  : A. Class 2 components of the Hydrogen Recombiner System (HCS) outside containment; B. Class 2 primary containment penetrations for HCS System, Ref. Nos. Z55 A and B, Z56 A and B, Z57 A and B Code Class  : 2 i

Examination Requirements  : IWA-5240, Performance of VT-2 visual examination during inservice pressure tests for components "A" and "B" above Basis for <

Relief  : A. Reliefis requested from ASME Section XI, IWA-5240, as l allowed by 10 CFR 50.55a (a)(3)(i). The HCS includes several hundred feet of uninsulated piping in potentially i contaminated overhead areas and approximately 250' of  !

insulated piping for personnel protection. Performance of the required visual examinations entails the removal of i insulation for each functional test and the application /

removal ofleak detection fluid. Disposal of the fluid, the l wipes used in fluid removal, and damaged insulation is a l significant radwaste impact. The activities associated with .

these examinations would result in plant life exposure to

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personnel of approximately 6.5 Man Rem. This  ;

constitutes a hardship in terms of radwaste disposal, resource commitment, and in maintaining ALARA.

B. Relief is requested from ASME Section XI IWA-5240 as allowed by 10 CFR 50.55a (a)(3)(i). Performance of the required visual examination does not provide an increase in the level of safety or quality because containment penetration integrity will be determined by performance of leakage rate testing to Appendix J (Type C) test method in lieu of ASME Section XI examinations. The subject containment penetrations were built to ASME Code Class 2 rules as required by ASME III Sub NE-1110(c).

The primary containment structure was also designed, fabricated, and examined to these rules, and is tested to Option B of Appendix J (Type A) requirements.

RELIEF REQUEST NO. IICS-PTRR-1, Revision 0 (cont'd.)

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l Testing the subject penetrations consistent with the testing requirements of the containment structure assures that the overall containment integrity is maintained commensurate with the appropriate level of safety and quality.

Alternate Examination (s)  : A. The structural integrity of HCS components outside i containment will be determined and monitored in accordance with Appendix "J" test method. Leakage which exceeds the Appendix "J" acceptance criteria and cannot be reduced to acceptable levels will be assumed to be pressure boundary leakage and a visual examination per IWA-5240 will be performed to identify the source of leakage.

B. The structural integrity of the subject penetrations will be determined by performing leakage rate testing in accordance with Appendix J requirements.

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