ML20065P463

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Comment Supporting Proposed Rule 10CFR50 Re Codes & Stds for Npps;Subsections IWE & Iwl
ML20065P463
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 04/25/1994
From: Dennis Morey
SOUTHERN NUCLEAR OPERATING CO.
To: Chilk S
NRC OFFICE OF THE SECRETARY (SECY)
References
FRN-59FR979, FRN-61FR41303, RULE-PR-50 59FR979-00013, 59FR979-13, AC93-2-017, AC93-2-15, AC93-2-16, AC93-2-17, NUDOCS 9404290100
Download: ML20065P463 (9)


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Docket Nos. 50-348 00CXE ANiiffiki,'k

50-364 hriANCH Mr. Samuel J. Chilk Secretary of the Comminion U.S. NuclearRegulatory Commission Washington, DC 20555 ATTENTION: Docketing and Service Branch Comments on Proposed Rule

" Codes and Standards for Nuclear Power Plants; Subsections IWE and IWL" (59 Federal Renister 979 of January 7.1994)

Dear Mr. Chilk:

Southern Nuclear Operating Company has reviewed the proposed rule " Codes and Standards for Nuclear Power Plants; Subsections IWE and IWL," published in the Federal Register on January 7,1994. In accordance with the request for comments, Southern Nuclear Operating Company is in total agreement with the NEI comments which are to be provided to the NRC.

In addition, Southern Nuclear Operating Company (SNC) is enclosing comments which are speciSc to the SNC plant.

Should you have any questions, please advise.

Respectfully submitted, b s Dave Mercy '

DNM/jdk g42gtoo940425 50 59FR979 PDR

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APR 25 '94 02:57PM SOUTHERN NUCLEAR 205 870 6103 P.3/19 1.

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U. S. Nuclear Regulatory Commission Page Two cc: Southern Nuclear Operating Company l R. D. Hill, Plant Manager U. S. Nuclear Reoulatory Commission. Washington. D. C.

B. L. Siegel, Licensing Project Manager, NRR U. S. Nuelaar Renulatory Commission Reaion 11 S. D. Ebneter, Regional Administrator T. M. Ross, Senior Resident inspector i

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APR 25 '94 02:58PM SOUTHERN NUCLEAR 205 STO 6508 P,4/19

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Enclosure Comments on the Proposed Rule

" Codes and Standards for Nuclear Power Plants; Subsections IWE and IWL" Ihese conunents are based on the review of thisproposed rule as it applies to our SNC Plant.

(01) Choosing the 1992 Edition with 1992 Addenda presents a problem to those plants which will be upgrading in the near fbture. We anticipate our three plants to be using the 1992 Edition with 1993 Addenda and it would be much easier if the IWE/IWL scope of work was to the same Edition and Addenda of the ASME Code as the remaining Section XI examinations.

(02) We are not convinced that the problems listed in the NRC SECY-93-328 are adequate to justify the implementation of these stringent requirements. There were only two cases of corrosion / degradation where thickness measurements revealed areas where the we thickness was at or below the minimum design thickness.

(03) The requirement of an expedited examination schedule is unnecessary. It puts an undue l burden on those plants that are updating to new Editions within the next couple of years. If a requirement is instituted to complete these examinations within a specific time-frame, we would propose seven and one-half years as a minimum to complete this scope of work. We feel that we would need a minimum of four outages at each of our units to develop the plan

! and complete the examinations called out in IWE and IWL.

l (04) The special allowance by the NRC of giving an extra two years for those plants which will

be upgrading in the near future is of no real beneSt since we will still have to complete the examinations within the same five year time-frame. As noted in (04), we would propose seven and one-half years as a more adequate time to complete his scope ofwork.

(05) Since the Proposed Rule doesn't require the submittal of an ISI Program to the NRC, we will need to submit Relief Requests to cover those cases where we are unable to meet these requirements.

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) Page Two Enclosure j!

i I hfollowing comments are related to Subsection JWE as apphcable to our SNC Plant:

i l (1)IWE has been developed for application to a new plant and thus should not be applied to existing plants. IfIWE is warranted to monitor containment integrity, then the requirements l should only be applicable to future plants so that IWE could be considered and mea +ad for l j during original plant design and construction. Existing plants already have programs in place ,

j to maintain the integrity of the containments and these programs should be allowed to l j contmue. 1 l

I (2) If the accessibility requirements ofIWE-1231 cannot be met, relief requests will be j j required. (i.e. access for visual examination from at least one side is required for; penetrations I

j and openings, structural discontinuities, single welded butt joints from the welded side, 80% of i

the contamment surface area, all surface areas subject to accelerated degradation).

j (3) NRC endorsement ofIWE will result in a flood of additional relief requests during plant l ISI Program updates with the resultant NRC review, rebuttal, approval process and extended l l periods of time before approved examination programs are in place. Containment integrity for ,

l j existing plants can be more efficiently maintained with existing industry initiatives and '

examination / testing programs.

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(4) We will be required that whenever paint or coatings are to be either removed or re-applied, l a visual examination is to be performed.

j l (5) It is our understanding that Paragraph (b) ofIWE-2420 applies only to the schedule of examinations required in Category E-C and not the examination methods. We would perform j i ~

i the examinations to the examination method called out under the specific Examination Category.

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! (6) Paragraph (b) ofIWE-2430, Additional Examinations, requires that if additional flaws or j areas of degradation are found in the first expanded scope, "all of the remaining examinations

) within the same category shall be performed to the extent specified in Table IWE 2500-1 for j the inspection interval". This is not a reasonable requirement in that it is much more restrictive

than even Class 1 component examinations in this situation.

] (7) TABLE IWE-2500 - EXAMINATION CATEGORIES i

j (A) EXAMINATION CATEGORY E-A, CONTAINMENT SURFACES l (1) This category requires visual examination (VT-3) of 100% of the accessibic surface j areas of containment at Farley. This is a very large scope of work considering the PWR i containment surfaces. Some of these examinations will have to be done remotely and

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! , .- 1 i APR 25 '94 02:59Pr1 SOUTHERN NUCLEPR 205 870 6108 P.6/19 l ,

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. Table IWA-2210-1 requires that the VT-3 examination be demonstrated such that a lower  !

! case character (0.105-in. tall) be seen remotely with proper illumination. This may not be possible and we would take exception to this requirement. In addition, there are concerns about outage impact and personnel safety since we would pinbably have to perform these j examinations from the polar crane.

Subsection IWE has included containment surface examination requirements which should be ofno concem for containment integrity. 10 CFR 50 Appendix J, paragraph V.A.,

presently includes requirements for a general visual examination of the interior and exterior containment surfaces prior to each ILRT which is sufficient to monitor general containment integrity.

Examinations should be limited to known problem areas or areas which are most susceptible to degradation based on engineering evaluation of the applicable designs, construction practices, materials, coatings and environments (e.g. non-coated wetted surfaces, drywell air gaps where forming material was not removed). Potential problem areas will probably not be suitable for muni@l visual examination and other examinacion methods would be required. Therefore a requirement for 100% visual examination of the accessible surface areas of the containment structure is unwarranted.

(2) Item number E1.20 requires VT-3 of 100% of the accessible surfaces of the -

containment vent system. nere needs to be a clear definition of the scope of this requirement. Item E1.12 requires VT-3 examination of100% of the accessible surfaces of the containment stmeture and the vent system would be part of the area included in this item.

(3) Item No. E1.11 requires a " General Visual" and Paragraph 1%T-3510.1 is referenced This paragraph requires the examinations performed by, or under the direction of a Registered Professional Engineer or another individual with equivalent experience and knowledge. There is no requirement in 10 CFR 50 Appendix J or other areas including the fracture mechanics analysis ofReactor Pressure Vessels which requires a Registered P.E..

This requirement is unnecessary as long as the personnel performing this work have the appropriate knowledge.

(B) EXAMINATION CATEGORY E-B, PRESSURE RETAINING WELDS (1) Item E3 10 Containment Penetration Welds and item E3.30 Nozzle-to Shell Welds (Category D), appear to be the same thing. Dere is no difference in these two items.

They both encompass welds of pipes which penetrate the containment shell. Item E3.30 scope includes 25% of the total number of welds, but item E3.10 includes only 25% of

APR 25 '94 03tOOPM SOUTHERN NUCLEAR 205 870 6108 P.7/19 Page Four Enclosure those welds subject to cyclic loads and thermal stresses. The entire containment structure is subject to cyclic loads and thermal stresses due to startup and shutdown of the reactor.-

The examination scope is unclear and additional explanation is required.

(2) Items listed in category E-B require VT-1 examination which requires the examiner access within 24" of the surface. Performance of VT-1 examinations ofwelds at our plants, e.g., dry-well, torus shells, and containment domes, will require extensive scaffolding and due to personnel safety concerns, may be considered to be inaccessible. In such cases, remote visual examinations should be allowed.

(C) EXAMINATION CATEGORY E-C, CONTAINMENT SURFACES REQUIRING AUGMENTED EXAMINATIONS (1) This category seems to have been developed to catch any areas of the containment which are subjected to questionable environmental conditions. Category E-C should be the only category included in the scope ofIWE. The existing visual examination requirements of 10 CFR 50 Appendix J prior to each ILRT should be sufficient for all but these areas which are subject to potentially accelerated degradation.

(2) Paragraph IWE-1240 defines those surface areas which require augmented examinations per Category E-C. The areas included tend to be consistent with those already identified by the industry due to operating experience and which utilities have already established examination requirements and contingency plans in response to regulatory documentation. Efforts by ASME XI to replace regulatory documents seems 1

prudent, but advantage should be taken for the years of operating experience and problems I

discovered. Category E-C addresses these problems, but an all encompassing examination program does not seemjusti6ed.

(D) EXAMINATION CATEGORY E-D, SEALS, GASKETS AND MOISTURE BARRIERS (1) Item E5.10 - Seals and E5.20 - Gaskets should not be included in the scope of examination. All openings containing seals or gaskets are subjected to leakrate testing on a frequency detennined by the Plant Technical Specifications and/or 10 CFR 50, Appendix J which is much more subjective and capable of detecting degradation than a general VT-3 examination. These items should be deleted from IWE since this is a redundant requirement.

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Page Five Enclosure (2) Item E5.30 identifies visual examination requirements for accessible moisture barrier seals. If the degradation of such seals could lead to degradation of the adjacent containment surfaces, then these areas should be included with Category E-C. However, engineering evaluation should be allowed to assess the requirements for exammation.

(E) EXAMINATION CATEGORY E-F, PRESSURE RETAINING DISSIMILAR hETAL WELDS I

(1) Item E7.10 requires the surface examination (liquid penetrant) of 50% of the total dissimilar metal welds included in the containment structure. These welds would be primarily associated with containment penetrations and would consist of flued head to  ;

penetration pipe welds and possible expansion bellows to pipe welds. When paint or coatings are removed, IWE would require that the surface be visually exammed prior to the paint or coatings being removed as well as after the examination and reapplication of the paint or coatings. Visual examination should be adequate to detect any corrosion activity or degradation of the subject welds. If degradation is detected visually, IWE would require that either a supplemental surface or volumetric exanimations would be performed.

(F) EXAMINATION CATEGORY E-G, PRESSURE RETAINING BOLTING

. (1) Visual exammation, VT-1, of bolted connections when they are disassembled seems prudent and justifiable and is probably already included in the plant's Appendix B program.

(2) Bo!t torque or tension tests each interval does not seem warranted. Pressure boundary bolted connections normally require specific procedures for installation and torquing.

These procedural requirements are applicable each time the connection is made. 10 CFR 50, Appendix J requires three ILRTs each 10-year interval which would identify any bolted connections with leakage above the acceptance criteria. Therefore an arbitrary bolt torque / tension test each inspection interval would not increase the level of contamment 4

integrity.

(G) EXAMINATION CATEGORY F P, ALL PRESSURE RETAINING COMPONENTS (1) Examination Category E-P seems to be a restatement of the 10 CFR 50, Appendix J leakrate testing requirements. At the present time, Appendix I requirements are separate from ASME XI and should remain that way until the NRC tasks some other organization development of with replacement requirements. The AShE O&M Code may eventually

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t i be tasked with development of an Appendix J replacement. If so, it will be included in the O&M Code. Referencing 10 CFR 50, Appendix J in IWE is repetitious and unnecessary.

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{ (8) ARTICLEIWE-5000 - SYSTEMPRESSURE TESTS i

! (A) This article addresses leakrate testing of the containment and seems unnecessary since leakrate tesdng is required by 10 CFR 50, Appendix J. IWE-5222 allows deferral of

! leakage tests until the next scheduled leakage test for certain repaira/ modifications. IWE

should not allow the deferral of a test which might be required by 10 CFR 50. Leakrate

{ testing requirements should be contained in only one document. Including any i requirements for leakrate testing in IWE will only confhse the issue more than it already is.

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j (B)IWE-5240 references requirements for visual examination per IWA-5246 which has i been deleted in the latest addenda to the 1992 Edition of ASME Section XI. Therefore the

} referenceis nonexistent.

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! Thefollowing comments are related to Subsection IWL as applicable to our SNC Plant i (applicable only to the Farley Nuclear Plant):

i (1) IWL has been developed for application to a new plant and thus should not be applied to i existing plants. IfIWL is warranted to monitor containment integrity, then the requirements

! should only be applicable to future plants so that IWL could be considered and accounted for j during original plant design and construction. Existing plants already have programs in place i to maintain the integrity of the contamments and these programs should be allowed to i continue.

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(2)IWL-2310 requires VT-1C and VT-3C examinations and the corresponding requirement j for the Owner's written practice to define the qualification, etc., for these certifications. It j does permit limited certification for examiners. IWL references IWA-2210; it would be our Intent to perform these examinations using a telescope and we would be required to i demonstrate that we could satisfy Table IWA-2210-1 in that a lower case character (0.105-
inches tall) be seen in the telescope.

i i (3) IWL-2320 requires " Responsible Engineer who shall be a Registered Professional Engineer experienced in evaluating the inservice condition of structural concrete. He shall have l

knowledge of the design and construction Codes and other criteria used in design :md construction of concrete containments in nuclear power plants."

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j This requirement does not correspond with other portions of Section XIin that there are no '

' such d*M instructions or requirements for similar fhnetions such as fracture whanics i analysis, etc. Many utilities will be forced to hire contractors to satisfy this requirement. In

addition,10 CFR 50 Appendix I has no such requirement and it appears to provide no real
benefit. At least IWE-3510.1 permitted the Owner to use another individual as long as the i individual had the appropriate knowledge. ,

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