ML20206E781

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Proposes Alternatives to Requirements of ASME B&PV Code Section XI,1992 Edition,1992 Addenda,As Listed.Approval of Alternative Request on or Before 990915,requested
ML20206E781
Person / Time
Site: Grand Gulf, Arkansas Nuclear, River Bend, Waterford  Entergy icon.png
Issue date: 04/29/1999
From: Kansler M
ENTERGY OPERATIONS, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CNRO-99-00004, CNRO-99-4, NUDOCS 9905050244
Download: ML20206E781 (18)
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'==Enteruv - Of

== w"' '"c-Jackson, MS 39286-1995 Tel 601368 5760

~ " Michael R. Kansler

%ce Presdent OperatensSupport -

j April 29,1999

. U. S. Nuclear Regulatory Commission Attn.: Document Control Desk Mail Stop OP1-17 Washington,'DC 20555-0001

Subject:

Entergy Operations, Inc.

Altematives to ASME Code Requirements Arkansas Nuclear One - Units 1 & 2 Grand Gulf Nuclear Station Docket Nos. 50-313 & 50-368 Docket No. 50-416 License Nos. DPR-51 & NPF 6 License No. NPF-29 River Bend Station Waterford Steam Electric Station - Unit 3 Docket No. 50-458 Docket No. 50-382 i License No. NPF-47 License No. NPF-38 CNRO-99/00004 Ladies and Gentlemen:

In the Federal Register dated August 8,1996 (61 FR 41303), the NRC amended its  !

regulations to incorporate by reference the 1992 Edition and Addenda of Subsections IWE and lWL of Section XI of the American Society of Mechanical Engineers (ASME) Code.

Subsections IWE and IWL give the requirements for inservice inspection (ISI) of Class MC (metallic containment) and Class CC (concrete containment).

Pursuant to 10CFR50.55a(a)(3), Entergy Operations, Inc. (Entergy) proposes alternatives to the requirements of ASME Boiler and Pressure Vessel Code Section XI,1992 Edition,1992 Addenda as denoted below.

j

  • Paragraph IWE-2420(b) as presented in Alternative Request IWE-01 (Attachment 1)

. Article IWE-2500, Table IWE-2500-1, " Examination Category E-G, Pressure Retaining Bolting", Item 8.20 as presented in Alternative Request IWE-02 (Attachment 2). This h&

Code item pertains to bolt torque or tension testing of Class MC pressure retaining bolting, e Article IWE-2500, Table IWE-2500-1, " Examination Category E-D," items 8E5.10 and E5.20 as presented in Alternative Request IWE-03 (Attachment 3). These Code ite'ms pertain to visual examination of seals and gaskets on airlocks, hatches, and other

' devices.

99050502h E990 M "3 DR ADOCK 0

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  • : Alt:rnativas to ASME Cods R:quirements 4 CNRO-99/00004 ' l April 29,1999 Page 2 of 3 These requests apply to Entergy's nucleat unitt: Arkansas Nuclear One - Units 1 and 2; Grand Gulf Nuclear Station; River Bend Station; and Waterford Steam Electric

- Station - Unit 3.

I Entergy is a participant in the Electric Power Research Institute (EPRI) project for the preparation of a generic IWE/lWL Program and Guide. The attached request is part of the development of that project.-

The NRC has approved similar alternative requests for Davis-Besse Nuclear Power Station',

Calvert Cliffs Nuclear Station 2, and Cooper Nuclear Station .

To support an upcoming refueling outage at Grand Gulf Nuclear Station, Entergy requests approval of the attached alternative request on or before September 15,1999. I Should you have any questions regarding this submittal, please contact Guy Davant at .4 (601) 368-5756.  !

Very truly yours, f

/GHD/baa  :

Att ents cc: . (next page) l l

l

' Letter dated June 30,1998," Relief from Certain ASME Code Requirernents for Inservice Inspection for Facility Operating License No. NPF Davis-Besse Nuclear Power Station, Unit 1 (TAC No.

.. MA0414)" '

8 Letter dated November 16,1998, " Evaluation of First Containment Inspection interval IWE/lWL Program Requests for Relief at Calvert Cliffs Nuclear Power Plant, Unit Nos.1 and 2 (TAC Nos.

MA2084 and MA2085)"

8 Lctter dated November 18,1998," Relief Authorization for Alternative to the Requirements ol ASME Section XI, as Endorsed by 10 CFR 50.55a for Containment inspection for Cooper Nuclear Station (TAC No. MA1163)"

p ,

  • Alt:rn;tiv s to ASME Cods Requir:ments CNRO-99/00004 April 29,1999

. Page 3 of 3 cc: Mr. C. M. Dugger (W-3)

Mr. R. K. Edington (RBS)

Mr. W. A. Eaton (GGNS) -

Mr. C. R. Hutchinson (ANO)

Mr. J. R. McGaha (ECH) j Mr. G. F. Dick, NRC Project Manager (Entergy)

' Ms. J. L. Dixon-Herrity, NRC Senior Resident inspector (GGNS)

Mr. T. R. Farnholtz, NRC Senior Resident inspector (W-3)

Mr. R. J. Fretz, NRC Project Manager (RBS)

Mr. N. D. Hilton, NRC Project Manager (ANO-1)

Mr. K. M. Kennedy, NRC Senior Resident inspector (ANO) j Mr. E. W. Merschoff, NRC Region IV Regional Administrator Mr. M. C. Nolan, NRC Project Manager (ANO-2)

Mr. C. P. Patel, NRC Project Manager (W-3) l Mr. G. D. Replogle, NRC Senior Resident inspector (RBS)

Mr. S. P. Sekerak, NRC Project Manager (GGNS) l

)

{

l l

l 3

I l

Alt:rnativ:s to ASME Cods Requiram:nts CNRO-99/00004 April 29,1999 bec:

  • Mr. W. B. Abraham (G-SSB1-NSR)

Mr. W. B. Brice (G-SSB2-NSA)

Mr. S. G. Brown (W-GSB-355)

Mr. M. M. Coombs (N-GSB)

Mr. R. M. Cooper (N-GSB)

Ms. K. A. Courtney (R-GSB-43)

Mr. J. R. Dunkelberg (R-GSB-36)

Mr. E. C. Ewing (W-GSB-310)

Mr. C. E. Forpahl (R-GSB-21)

Mr. W. K. Hughey (G-SSB1-NSR)

Mr. W. L. Justice (M-ECH-36)

Mr. R. J. King (R-GSB-42)

Ms. A. L. Lacey (R-GSB-43)

Ms. J. M. Manzella (W GSB-318)

Ms. N. A. Mosher (N-GSB)

Mr. A. J. Nguyen (R GSB-21)

Ms. M. B. Padgett (R-GSB-46)

Mr. M. J. Paterak (N-GSB)

Mr. E. P. Perkins (W-GSB-318)

Mr. R. D. Rispoli (N-GSB) 2 Mr. L. A. Shay (N-GSB)

Mr. C. W. Taylor (W-GSB-318)

Mr. J. D. Vandergrift (N-GSB)

Mr. D. S. Waldron (N-TSB)

Mr. E. C. Williamson (G-M&E2-NPE)

Central File (GGNS)

Corporate File (18]

DCC (ANO)

SDC (RBS)

Records Center (W3) l 4

CNRO-99/00004 Att chm:nt 1 Page 1 of 2 ARKANSAS NUCLEAR ONE- UNITS 1 & 2 GRAND GULF NUCLEAR STATION RIVER BEND STATION WATERFORD STEAM ELECTRIC STATION - UNIT 3 EXAMINATION OF CONTAINMENT REPAIRS ALTERNATIVE REQUEST # JWE-01, Rev. O SYSTEMS / COMPONENTS FOR WHICH AN ALTERNATIVE IS PROPOSED Class MC containments and metallic liners of Class CC containments, ASME Section XI, 1992 Edition,1992 Addenda, Paragraph IWE-2420(b).

CODE REQUIREMENTS Under the ASME inservice Inspection (ISI) program, component examination results may require evaluation of flaws, areas of degradation, or repairs in accordance with Article IWE-3000," Acceptance Standards." ASME Section XI,1992 Edition,1992 Addenda, Paragraph IWE-2420(b) states that if a component is examined and found acceptable for continued service, the areas containing flaws, degradation, or repairs shall be reexamined during the next inspection period listed in the schedule of the inspection program of Paragraph IWE-2411. " Inspection Program A," or Paragraph IWE-2412, " Inspection Program B,"in accordance with Table IWE-2500-1, " Examination Category E-C."

CODE REQUIREMENT FOR WHICH AN ALTERNATIVE IS PROPOSED Pursuant to 10CFR50.55a(a)(3)(ii), Entergy proposes an alternative to performing examinations on repaired areas as required by Paragraph IWE-2420(b). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

BASIS FOR ALTERNATIVE 10 CFR 50.55a was amended, as cited in the Federa/ Register (61 FR 41303), to require the use of the 1992 edition,1992 Addenda, of Section XI, when performing containment examinations. The purpose of a repair is to restore the component to an acceptable condition of continued service in accordance with the acceptance standards of Article IWE-3000.

Paragraph IWA-4150, " Verification of Acceptability," requires the owner to evaluate the suitability of the repair, considering the cause of the failure. If the repair has restored the component to an acceptable condition, successive examinations are not warranted. If the repair was not suitable, then the repair does not meet Code requirements and the component would not be acceptable for continued service without an additional engineering evaluation. Neither Paragraphs IWB-2420(b), IWC-2420(b), nor IWD-2420(b) require a

CNRO-99/00004 Attachment 1 Page 2 of 2

' repa?r to be subject to successive examination requirements. Furthermore,if the repair area I is subject to accelerated degradation, it would still require augmented examination in accordance with Table IWE-2500-1, " Examination Category E-C." Therefore, successive  !

examination of repairs in accordance with Paragraph IWE-2420(b) constitutes a burden without a compensating increase in quality or safety.

In SECY 96-080," Issuance of Final Amendment to 10 CFR Section 50.55a to incorporate by Reference the ASME Boiler and Pressure Vessel Code (ASME Code),Section XI, Division 1, Subsection IWE and Subsection IWL," dated April 17,1996, response to Comment #3.3 states: l i

"The purpose of IWE-2420(b)is to manage components found to be acceptable for continued service (meaning no repair or replacement at this time) as an Examination Category E-C component... If the component had been repaired or replaced, then the more frequent examination would not be needed." l The requirement to perform successive examinations following repairs has been removed in the rewrite of Subsection IWE of ASME Section XI. This rewrite has been approved by ASME and has been published in the 1998 Edition. This alternative only applies when the flaws or degradations are corrected by repairs and not when accepted by " engineering 1 analysis." l In addition, the NRC has approved similar relief requests for Davis-Besse Nuclear Power Station (#RR-E6)' and Cooper Nuclear Station (#RC-04)5 ALTERNATIVE TESTING Successive examinations in accordance with Paragraph IWE-2420(b) are not required for repairs made in accordance with Article IWA-4000.

  • Letter dated June 30,1998, " Relief from Certain ASME Code Requirements for Inservice inspection for Facility Operating License No. NPF Davis-Besse Nuclear Power Station, Unit 1 (TAC No.

MA0414)"

5 Letter dated November 18,1998," Relief Authorization for Alternative to the Requirements of ASME Section XI, as Endorsed by 10 CFR 50.55a for Containment inspection for Cooper Nuclear Station (TAC No. MA1163)"

]

CNRO-99/00004 l

Attachm:nt 2 l Page 1 of 4 '

l ARKANSAS NUCLEAR ONE - UNITS 1 & 2 GRAND GULF NUCLEAR STATION ,

RIVER BEND STATION I WATERFORD STEAM ELECTRIC STATION - UNIT 3 CONTAINMENT INSPECTION BOLTING TORQUE / TENSION TEST ,

ALTERNATIVE REQUEST # IWE-02, Rev. O SYSTEMS / COMPONENTS FOR WHICH AN ALTERNATIVE IS PROPOSED Class MC pressure retaining bolting, Examination Category E-G, item 8.20 of IWE-2500,

" Examination and Pressure Test Requirements" Table IWE-2500-1, ASME Section XI,1992 Edition with the 1992 Addenda.

CODE REQUIREMENT ASME Section XI,1992 Edition with 1992 Addenda, Table IWE-2500-1 requires a bolt torque or tension test once each interval.

CODE REQUIREMENT FOR WHICH AN ALTERNATIVE IS PROPOSED Pursuant to 10CFR50.55a(a)(3)(ii), Entergy proposes an alternative to performing the Code-required bolt torque or tension test on the bolt connections that are not disassembled and reassembled during the inspection interval. The torque or tension testing will result in hardship without commensurate increase in the level of safety or quality.

BASIS FOR ALTERNATIVE 10CFR50.55a was amended, as cited in the Federal Register (61 FR 41303), to require the use of the 1992 Edition,1992 Addenda, of ASME Section XI when performing containment examinations. Bolt torque or tension testing is required on bolted connections that have not been disassembled and reassembled during the inspection interval. Determining the torque or tension value would require the bolting to be loosened and then re-torqued or re-tensioned. Discussions of bolted connections are presented below for each Entergy site.

These discussions address pressure-seating and pressure-unseating bolted connections.

Pressure-seating bolted connections are considered to be those connections that have additional seating loads due to accident pressures on the inboard (containment) side of the penetration. Thus pressure-seating connections have a low potential for leakage under accident loads. In contrast, pressure-unseating bolted connections see unseating loads due to accident pressures on the inboard (containment) side of the penetration. Therefore, the potential for leakage through a pressure-unseating connection is greater than for a pressure-seating connection. As a result, the integrity of the connection is more dependent on proper tensioning of the treaded fasteners, possibly increasing the potential for leakage.

CNRO-99/00004 Attachm:nt 2 Page 2 of 4 Arkansas Nuclear One 1.

Penetration bolted connections are pressure-seating, except in four cases as discussed below. Specifically, the equipment hatch bolted connections seat against the interior surface of containment during containment pressurization and are therefore pressure-seating. The bolted connections associated with the fuel transfer tube blind flange are also pressure-seating. The exceptions are:

a. The personnel hatches for both units are pressure-unseating if the pressure-seating connections on the containment side fail or if the containment side of the hatch assembly fails,
b. The emergency personnel hatches for both units are pressure-unseating if the pressure-seating connections on the containment side fail.
c. The Emergency Personnel Hatch Telephone Penetration Assembly bolting for ANO-2 is pressure-ur. seating if the containment side of the hatch assembly fails.
d. The ANO-2 electrical penetration assemblies have a penetration header plate with redundant 0-rings that is attached to the weld flange with bolting on the Auxiliary Building side. These connections are pressure-unseating.
2. Grand Gulf Nuclear Station Penetration bolted connections are pressure-seating, except for the following two cases:
a. Both bulkheads on both containment personnel airlocks are f;tted with an electrical penetration assembly. Each of the four electrical penetration assemblies has a pressure-seating connection on the inboard side and a pressure-unseating connection on the outboard side. Thus, pressure loading on the unseating connection would only occur upon failure of the pressure-seating connection,
b. Both containment airlocks have a bolted handwheel shaft seal retainer and a bolted blind flange used for testing on the outboard bulkhead. (The flange is local leak-rate tested.) Thus, pressure loading on these unseating connections would occur only if the inboard door is open, or if the inboard bulkhead is breached.
3. River Bend Station

]

Penetration bolted connections are pressure-seating, except for the following two cases:

l l a. The equipment hatch seats against the exterior surface of the containment and is

! therefore pressure-unseating. The equipment hatch is removed during -

i maintenance outages, when necessary, and during each refueling outage. Prior to plant startup, the hatch and flange are Type B leak-tested in accordance with 10CFR50 Appendix J. ]

1 L ..

e- y CNRO-99/00004 Attachment 2 Page 3 of 4

b. The fuel transfer tube blind flange bolting connection is pressure-unseating. The blind flange is removed during each refueling outage. Prior to plant startup, the flange is Type B leak-tested in accordance with 10CFR50 Appendix J.
4. 'Waterford-3 Penetration bolted connections are pressure-seating except for bolted connections

- located within the exterior personnel airlock doors. These connections are Type B pressure-tested in a pressure-unseating fashion during leak tests of the airlocks in accordance with 10CFR50 Appendix J.

Each containment penetration is Type B leak-te.sted in accordance with 10CFR50 Appendix J. Successfully performing the Type B test itself proves the bolt torque or tension remains adequate to provide a leak rate within acceptable limits. The torque or tension value of bolting becomes an issue only if the leak rate is excessive. Once a bolt is torqued or tensioned, it is not subject to dynamic loading that could cause it to experience significant change. Appendix J testing and visual inspection are adequate to demonstrate the design function is met. Torque or tension testing is not required for any other ASME Section XI, Class 1,2, or 3 bolted connection or its supports as part of the Inservice Inspection program.

The requirement to perform bolt torque or tension tests has been removed from the 1998 Edition of Subsect!on IWE of ASME Section XI. Entergy believes 10CFR50, Appendix J

. Type B testing provides an equivalent level of quality and safety to the bolt torque testing required by Table IWE-2500-1. Therefore, loosening and subsequent re torquing bolted connections that are verified leak-tight per Appendix J testing results in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

The NRC has approved a similar request for Davis-Besse Nuclear Power Station (#RR-E7)*.

ALTERNATE EXAMINATIONS The following examinations and tests required by Subsection IWE ensure the structural integrity and the leak-tightness of Class MC pressure retaining bolting; therefore, no additional altemative examinations are proposed:

1. Exposed surfaces of bolted connections shall be visually examined in accordance with

. requirements of Table IWE-2500-1, Examination Category E-G, Pressure Retaining Bolting, item No. E8.10.

a. l l

l

  • Letter dated June 30,1998," Relief from Certain ASME Code Requirements for Inservice inspection for Facility Operating License No. NPF Davis-Besse Nuclear Power Station, Unit 1 (TAC No.

MA0414)" -

t

CNRO-99/00004 Attachment 2 Page 4 of 4

2. Bolted connections shall meet the pressure test requirements of Table IWE-2500-1, Examination Category E-P, All Pressure Retaining Components, item E9.40.

In addition,10CFR50 Appendix J Type B testing is currently performed on each containment penetration at least once each inspection interval.

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F l CNRO-99/00004 l Attachm:nt 3 l l

Page 1 of 8 I l ARKANSAS NUCLEAR ONE- UNITS 1 & 2 GRAND GULF NUCLEAR STATION RIVER BEND STATION WATERFORD STEAM ELECTRIC STATION - UNIT 3 CONTAINMENT INSPECTION SEALS AND GASKETS ALTERNATIVE REQUEST # IWE-03, Rev. 0 l

I SYSTEMS / COMPONENTS FOR WHICH AN ALTERNATIVE IS REQUESTED l l

Seals and gaskets of Class MC pressure retaining components, Examination Category E-D, i items E5.10 and E5.20 of IWE-2500," Examination and Pressure Test Requirements," Table IWE-2500-1, ASME Section XI,1992 Edition,1992 Addenda.

CODE REQUIREMENT ASME Section XI,1992 Edition,1992 Addenda, IWE-2500, Table IWE-2500-1 requires seals and gaskets on airlocks, hatches, and other devices to be visually examined (VT-3) once each interval to assure containment leak-tight integrity.

CODE REQUIREMENT FOR WHICH AN ALTERNATIVE IS PROPOSED Pursuant to 10CFR50.55a(a)(3)(i), Entergy proposes an alternative to the Code-required visual examination (VT-3) on containment seals and gaskets as discussed below. Entergy believes the alternative examination presented below provides an acceptable level of quality and safety by ensuring the integrity of containment penetration seals and gaskets.

BASIS FOR ALTERNATIVE 10CFR50.55a was amended, as cited in the Federa/ Register (61 FR 41303), to require the use of the 1992 Edition,1992 Addenda of Section XI when performing containment examinations. As stated above, ASME Section XI,1992 Edition,1992 Addenda, IWE-2500, Table IWE-2500-1 requires seals and gaskets on airlocks, hatches, and other devices to be visually examined (VT-3) once each interval to assure containment leak-tight integrity. A discussion of penetrations containing seals and gaskets is presented below for each Entergy

- site.

1. Arkansas Nuclear One
a. Electrical Penetrations i

ANO-1 uses electrical penetration assemblies manufactured by Conax. The penetration assembly flange face is welded tc the penetration nozzle both inside and outside the Reactor Building. Modules through which electrical conductors pass are L

e v CNRO-99/00004

_ Attrchment 3

Page 2 of 8 i

' installed in the header plate. The Conax assembly uses a set of compression fittings to assure leak-tight integrity with the exception of modules for medium voltage

- penetrations that use a double O-ring configuration to assure leak-tight integrity. A j representative sample group is Type B leak-tested in accordance with 10CFR50, Appendix J every refueling outage in accordance.

ANO-2 uses electrical penetration assemblies manufactured by Amphenol and Conax. The penetration assembly flange face is welded to the penetration nozzle on the exterior face of the Reactor Building. A penetration hea_ der plate with redundant 0-rings is attached to the weld flange with bolting. Modules through which electrical

- conductors pass are installed in the header plate. The Amphenol assembly uses L

seals and gaskets to assure leak-tight integrity. The Conax assembly, which is used as replacement modules on several ANO-2 electrical penetrations, uses a set of compression fittings and redundant 0-rings to assure leak-tight integrity. Penetration assemblies are currently Type B leak-tested in accordance with 10CFR50 Appendix J.-

Both ANO-1 and ANO-2 seats and gaskets cannot be inspected without disassembly l of the penetration to gain access to the seals and gaskets,

b. Containment Equipment Hatch i

The containment equipment hatches at both ANO units have double O-ring seals on

- the hatch head assembly which when bolted tight to the hatch shell assembly forms a leak-tight seal. The equipment hatch is removed during maintenance outages, when necessary, and during each refueling outage. Prior to final closure, the hatch gaskets and door sealing face are inspected for damage that could prevent sealing.

Seals are typically replaced each outage on the ANO-1 and -2 hatches. Additionally, the containment equipment hatch procedures for both units require seals to be coated with an approved silicone lubricant to preserve their integrity. After final '

closure, the hatches are subjected to a 10CFR50 Appendix J, Type B teak test.

c. Containment Personnel Airlocks The containment' personnel airlocks at both ANO units use inner and outer doors with double gaskets without inflatable seals. These airlocks also contain other seals including handwheel shaft seals, eleWical penetration seals, double O-ring seals for blank flanges, viewing port O-ring seals, and seals for the equalizing pressure connections. Each affected component requires disassembly of the joint or subassembly to gain accessc The disassembly of these subcomponents, with the exception of the electrical and telephone penetration seals and the door gaskets,

' involves unbolting, visual examination of the seat or gasket for damage, reassembly and retightening the bolted connections.

A VT-3 examination of the airlock door gasket cannot ensure leak tightness because the backside of the airlock door gasket assemblies is inaccessible, in order for the l-E

7 CNRO-99/00004 l Attachment 3 I Page 3 of 8 l 1

1

' VT-3 examination to be successfully completed the gasket or seat must be removed )

which could result in mechanical damage necessitating replacement. These seals i and gaskets are replaced on a specified replacement interval based on vendor I recommendations and engineering evaluations. The personnel airlocks and the subcomponents noted above are currently Type B leak tested in accordance with 10CFR50 Appendix J

d. FuelTransferTube The fuel transfer tube penetrations on both ANO units usa a bolted blind flange with two gaskets to provide a leak-tight seal on this penetration. For ANO-1, these I gaskets are replaced each time the penetration is opened due to plant preference.

On ANO-2, these seals are inspected for damage prior to closure of the fuel transfer tube and replaced if damaged. Removal of these seals for inspection could result in  !

damage, necessitating their replacement. The fuel transfer tube penetrations are {

currently Type B leak-tested in accordance with 10CFR50 Appendix J. l

2. Grand Gulf Nuclear Station l
a. Electrical Penetrations l l

The electrical penetrations at Grand Gulf associated with this relief request have  !

either ceramic bushings or 0-rings serving as the containment boundary. The seals and gaskets of the electrical penetrations cannot be inspected without disassembly of the penetration to gain access to the seals and gaskets. Currently, there is no a scheduled maintenance task for periodic disassembly of the electrical penetrations that would allow inspection of the seals and gaskets. Penetration assemblies are currently Type B leak-tested in accordance with 10CFR50 Appendix J.

b. Containment Equipment Hatch The containment equipment hatch at Grand Gulf has double O-ring seals on the hatch head assembly which, when bolted tight to the hatch shell assembly, form a leak-tight seal. The equipment hatch is removed during maintenance outages, when necessary, and during each refueling outage. Prior to final closure, the hatch gaskets and door sealing face are inspected for damage that could prevent sealing.

Seals are replaced if found damaged. In addition, seats are typically replaced in accordance with the manufacturer's recommendations. The Preventive Maintenance program also requires the seals to be coated with an approved silicone lubricant to '

preserve their integrity. The equipment hatch is currently Type B leak-tested in accordance with 10CFR50 Appendix J. '

c. Containment Personnel Airlocks The containment personnel airlocks use inner and outer doors with double inflatable seats on each door to ensure leak-tight integrity. These inflatable seats are

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CNRO-99/00004 Attachm:nt 3 Page 4 of 8 i

accessible for VT-3 inspection without disassembly. However, the VT-3 inspection is l redundant to the 10CFR50 Appendix J, Type B test performed in accordance with the Primary Containment Leakrate Testing Program. These airlocks also contain

'other seals including handwheel shaft seals, electrical penetration seals, double O-ring seals for blank flanges, viewing port 0-ring seals, and seals for the equalizing

pressure connections. Each affected component requires disassembly to gain E

access. The Preventive Maintenance program typically requires replacement of the inflatable seals in accordance with the manufacturer's recommendations. The personnel airlocks are currently Type B leak-tested in accordance with 10CFR50 Appendix J.

d. Horizontal Fuel Transfer Tube The horizontal fuel transfer tube has double O-ring seals on the hatch head which, i when clamped in place on the inside surface of the containment, provides a  !

pressure-seating leak-tight seal. The seals are currently Type C water tested in j

. accordance with 10CFR50 Appendix J. J

3. River Bend Station
a. Electrical Penetrations -

River Bend uses electrical penetration assemblies manufactured by Conax. The assembly includes a canister subassembly, which is inserted in a penetration nozzle L

of suitable diameter. The header plate of the canister subassembly is attached by bolts to the penetration flange. Modules through which electrical conductors pass are installed in the header plate. These modules use ferruled compression fittings to

. ensure leak tightness at the header plate. A double O-ring seal is used between the header plate and flange face to assure leak-tight integrity.

The' seals and gaskets of the electrical penetrations cannot be inspected without disassembly of the penetration to gain access to the seals and gaskets. There is no task for periodic disassembly of the electrical penetrations to inspect or replace the seals and gaskets. Penetration assemblies are currently Type B leak-tested in accordance with 10CFR50 Appendix J.
b. Containment Equipment Hatch
The containment equipment hatch has double O-ring seals on the hatch head assembly which, when bolted tight to the hatch shell assembly, form a leak-tight seal.

The equipment hatch is removed during maintenance outages, when necessary, and L

during each refueling outage. Prior to final closure, the hatch gaskets and door sealing face are inspected for damage that could prevent sealing. Seals are replaced if found damaged. The equipment hatch is currently Type B leak-tested in accordance with 10CFR50 Appendix J.

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U

  • CNRO-99/00004 Att:chment 3 Page 5 of 8 c'. Containment Personnel Airlocks The containment personnel airlocks use inner and outer doors with double inflatable seals on each door to ensure leak-tight integrity. These inflatable seals are '

accessible for VT-3 inspection without disassembly. However, the VT-3 inspection is redundant to the 10CFR50 Appendix J Type B test performed in accordance with the Primary Containment Leakrate Testing Program. These airlocks also contain other seals including handwheel shaft seals, electrical penetration seals, double O-ring seals for blank flanges, and viewing port 0-ring seals. Each affected component requires disassembly to gain access. The personnel airlocks are currently Type B leak-tested in accordance with 10CFR50 Appendix J.

d. Inclined Fuel Transfer Tube The inclined fuel transfer tube has triple O-ring seals on the blind flange which when in the closed position isolates the containment. The blind flange is removed during refueling outages for fuel transfer. The three O-rings are replaced every refueling outage with a leak test performed on the flange prior to plant startup. The inclined fuel transfer tube is currently Type B leak-tested in accordance with 10CFR50 Appendix J.
e. Containment Control Rod Drive (CRD) Removal Tube The CRD removal tube hatch uses double O-ring seals between the head cover and the flange at the bolted connection. The hatch cover is open during outages, as necessary, to support CRD removal. The containment CRD removal tube is Type B leak-tested in accordance with 10CFR50 Appendix J.
4. Waterford-3
a. Electrical Penetrations Waterford uses electrical penetration assemblies manufactured by Conax. The penetration assembly flange face is welded to the penetration nozzle inside the containment vessel. Modules through which electrical conductors pass are installed in the header plate. These modules use ferruled compression fittings to ensure leak tightness at the header plate. Resin seals ensure leak tightness within the ferruled modules.

The seals and gaskets of the electrical penetrations cannot be inspected without disassembly of the penetration to gain access to the seals and gaskets. There is no task for periodic disassembly of the electrical penetrations to inspect or replace the ,

seals and gaskets. Penetration assemblies are currently Type B leak-tested in accordance with 10CFR50 Appendix J.

CNRO-99/00004 l- Attrchm:nt 3 l Page 6 of 8 l

b'. Containment Equipment Hatch The containment equipment hatch has double O-ring seals on the hatch head assembly which, when bolted tight to the hatch shell assembly, form a leak-tight seal.

l The equipment hatch is removed during maintenance outages, when necessary, and during each refueling outage. Prior to final closure, the hatch gaskets and door sealing face cro inspected for damage that could prevent sealing. Seals are replaced if found damaged, in addition, the seals are periodically replaced in accordance with the manufacturer's recommendations. The equipment hatch is currently Type B leak-tested in accordance with 10CFR50 Appendix J.

c. Containment Personnel Airlocks The containment personnel airlocks use inner and outer doors with double inflatable seals on each door to ensure leak-tight integrity. These inflatable seals are accessible for VT-3 inspection without disassembly. However, the VT-3 inspection is redundant to the 10CFR50 Appendix J Type B test in accordance with the Primary Containment Leakrate Testing Program. These airlocks also contain other seals including handwheel shaft seals, electrical penetration seals, seals for blank flanges, and seals for the equalizing pressure connections. Many of these components 3 require disassembly of a complex door operating mechanism to gain access for inspection. Disassembly of the door mechanism would require disabling the door pair interlocks and would significantly increase the likelihood of damaging the door mechanism. The personnel airlocks are currently Type B leak-tested in accordance with 10CFR50 Appendix J.
d. FuelTransferTube The fuel transfer tube uses double O-ring seals on a bolted flange. .These seals are Type B leak-tested in accordance with 10CFR50 Appendix J prior to plant startup following each refueling outage.

As discussed above, seals and gaskets receive a 10CFR50 Appendix J Type B test.. As noted in 10CFR50 Appendix J, the purpose of Type B tests is to measure leakage of containment penetrations whose design incorporates resilient seals, gaskets, sealant compounds, and electrical penetrations fitted with flexible metal seal assemblies.

Examination of seals and gaskets requires the joints that are proven adequate through

. Appendix J testing to be disassembled. For typical electrical penetrations, this would involve:

1. Pre-maintenance Appendix J testing
2. De-termination of cables at electrical penetrations if enough cable slack is not available l t:

L 3. Disassembly of the joint

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CNRO-99/00004 1

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Attachment 3 '

L Page 7 of 8 l

4. Removal and examination of the seals and gaskets
5. Reassembly of thejoint I
6. Re-termiriation of the cables if necessary.

.7. Post-maintenance testing of the cables 1

8.' Post-maintenance Appendix J testing of the penetration The work required for the containment hatches would be similar except for the de-termination, re-termination, and testing of cables; This imposes the risk that equipment could be damaged. The 1992 Edition,1993 Addenda of ASME Section XI recognize that disassembly of joints to perform these examinations is not warranted. Note 1 in Examination Category E-D of ASME Section XI states that sealed or Oasket connections need not be disassembled solely for performance of examinations. However, without disassembly, the seals and gaskets are inaccessible.

Seals and gaskets are not part of the containment pressure boundary under current Code rules [ASME Section lil, Subarticle NE-2121(b)]. When the airlocks and hatches containing these materials are tested in accordance with 10CFR50 Appendix J, degradation of the seal or gasket material would be revealed by an increase in the leakage rate if the leakage rate increases, corrective measures would be applied and the component retested. Repair or -

- replacement of seals and gaskets is not subject to Code rules (1992 Edition,1992 Addenda) in accordance with Paragraph IWA-4111(b)(5) of ASME Section XI.

. As discussed in the plant-specific sections above, penetrations that are routinely j disassembled are Type B leak-tested upon final assembly prior to startup. Since the Type B -

test assures the leak-tight integrity of primary containment, performing a visual examination would not provide an increase in the level of safety or quality.

l The requirement to examine seals and gaskets has been removed in the rewrite of ' l Subsection IWE of ASME Section XI. This rewrite has been approved by ASME and was

~

I published in the .1998 edition. ' In addition, the NRC has approved similar altemative.  !

requests for Davis-Besse Nuclear Power Station (#RR-E1)7, Calvert Cliffs Nuclear Station

[(#E1)', and Cooper Nuclear Station (#RC-02)'.

' Letter dated June 30,1998," Relief from Certain ASME Code Requirements for Inservice inspection for Facility Operating License No. NPF Davis Besse Nuclear Power Station, Unit 1 (TAC No.

MA0414)*

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  • Letter dated November 16,1998, " Evaluation of First Containment inspection Interval IWEllWL
Program Requests for Relief at Calvert Cliffs Nuclear Power Plant, Unit Nos.1 and 2 (TAC Nos.

! MA2084 and MA2085)"

' Letter dated November 18,1998," Relief Authorization for Alternative to the Requirements of ASME

'Section XI, as Endorsed by 10 CFR 50.55a for Containment inspection for Cooper Nuclear Station (TAC No. MA1163)"

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. q CNRO-99/00004 Att chment 3 l Page 8 of 8 i

ALTkRNATIVE EXAMINATION l

The leak-tightness of seals and gaskets is verified by local leak-rate testing in accordance with 10CFR50 Appendix J. This testing is performed at least once each inspection interval.

Testing the seals and gaskets in accordance with 10CFR50 Appendix J provides adequate I

assurance of the leak-tight integrity of the seals and gaskets.

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