ML20217P548

Comment Supporting Proposed Rule 10CFR50 Re Proposed Changes to Industry Codes & Stds

ML20217P548
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	04/06/1998
From:	Sen G VERMONT YANKEE NUCLEAR POWER CORP.
To:	NRC OFFICE OF THE SECRETARY (SECY)
References
FRN-62FR63892, RULE-PR-50 62FR63892-00055, 62FR63892-55, BVY-98-54, NUDOCS 9804100121
Download: ML20217P548 (6)

Text

VERMONT YANKEE

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NUCLEAR POWER CORPORATION DgJED

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C 185 Old Ferry Road, Brattleboro, VT 05301-7002 (802) 257-5271 g g,,g g April 6,1998 BVY 98-54 U

Secretary, U. S. Nuclear Regulatory Commission ATTN: Rulemaking and Adjudication's Staff Washington, DC 20555-0001 DOCKET NUMBER PROPOSED RULE N SO

Subject:

Vermont Yankee Nuclear Power Station I icense No. DPH-28 (Docket 50-271) b M 6 3 6'E,l1)

Comments on NRC Proposed Changes to 10CFR Part 50, 55 Industry Codes and Standards (Volume 62 Federal Register, Number 232, page 63892, dated December 3,1997)

Enclosed are Vermont Yankee Nuclear Power Corporation's (VY) comments on the proposed changes to 10 CFR 50.55a, Industry Codes and Standards. The comments are focused on changes related to the proposed required implementation of ASME Section XI, Appendix Vill, and the potentialimpact to the Inservice inspection Program.

VY's participation in the Performance Demonstration Initiative (PDl) provides first hand knowledge that modifications to ASME Section XI Appendix Vill incorporated in the PDI approach are necessary to make the program workable. PDI participation also supports the concem that information used by the NRC to prepare the 10CFR50.55a amendment is inaccurate in ceitain cases, and as such, does not truly reprosent the industry's capability to comply with the proposed rule. Furthermore, the ASME Section XI Appendix Vill modifications in thi proposed rule willimpose an unreasonable implementation and monetary burden without technical justification.

VY continues to be involved in industry initiatives developing or enhancing technology related to increased confidence in inspection data. As an example, VY is providing representation on the ASME Task Team preparing an Appendix Vill Rewrite Code Case. The subject Code Case is intended to replace Appendix Vill and resolve remaining discrepancies between the Code and the PDI. NRC personnel also serve on the Task Team.

In addition to the objection of expedited implementation, the enclosed comments document objection and provide altematives for the three NRC modifications to the ASME Code. The proposed modifications are, in brief,1) increase in annual training hours,2) allowing only cracks in test samples,3) representative

/f microstructure for samples used to qualify single-sided examinations.

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Considering the significant negative impact of the proposed rule as described in the enclosed comments, it is recommended that the 6-month expedited implementation requirement be removed and the three proposed modifications to the ASME Code be removed. It is extremely important for NRC Staff and senior management to work with PDI to resolve the above issues prior to publication of the final rule.

9804100121 980406 I

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50 62FR63892 PDR

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VERMONT YANKEE NUCLEAR POWER CORPORATION U. S. Nuclear Regulatory Commission BW 98-54 Page 2 Should you have any questions, please contact this office.

Sincerely, VpMONT YANKEE NUCLEAR POWER CORPORATION i

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Gautam Sen Licensing Manager Attachment oc:

USNRC Project Manager, WNPS

~ USNRC RegonI, Administrator USNRC Resident inspector, WNPS VT Department of Public Service

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/4 VERMONT YANKEE NUCLEAR POWER CORPORATION L 3

l U. S. Nuclear Regulatory Commission BVY 96-54/ Attachment Page 1 of 4 COMMENTS ON PROPOSED RULE

The nuclear industry has long recognized the need for a program like that in Appendix Vill of ASME Secten XI. The positen of the industry in that regard has not changed. We still believe that a program to ariarpately demonstrale ultrasonic procedures and personnelis sppicp,M However,in its present state, Appendix Vill is not workable. ASME recognizes that it has made a mistake in not producmg a Code Case rather than a -

Code change for this requirement scope prior to a trial implementation.

It is recognized that the NRC could perceive that it has been receivmg mixed signals from the industry in this regard. The industry has stated that without a rule making, the industry will have a hard time convincing the utilities to fund more progress on Appendix Vill and further qualificatens. Yet, when the NRC proposes just such a rule, it will receive many negative comments.. It is important, however, to recognize that the industry is wilhng to implement an ultrasonic qualificaten program and that the rule making must be within the framework of a workable program.

' The industry must do its part to make the qualification program workable. One d the main problems with j

Appendix Vill and the Performance Demonstration initiative is that the rules that the PDI have been using to qualify ultrasonic procedures and personnel do not meet ASME Secten XI, Appendix Vill as it was written.~

The PDI had to do this in order for the program to be workable. Numerous Code Cases have been

. introduced and passed to rectify these discrepances, although, many discrepancies remain. ASME is now in the process of developing an " Appendix Vlli Rewrite" Code Case that would take the place of Appendix Vill and which would remedy the remainmg discrepancies.

O The NRC states in the proposed rule (2.4.2) their strong disagreement that Appendix Vill as implemented by L

the PDI should be an altamative to the present Code rules, if an " Appendix Vill Rewrite" Code Case were.

developed and passed by ASME, this problem would be alleviated. However, this Code Case does not yet exist. It is estimated that the earbost such a Code Case would be available would be in the fall of 1996.

However,this is very optimistic.

Another problem with the Appendix Vill rule making is that the industry is not yet ready to implement many of the Appendix Vill Supplements. The proposed rule-making states that there are 300 personnel with piping i

and/or bolting qualifications and five vendor teams with vessel qualifications.~ This is true, but those piping qualifcatons are limited to wolds of similar metals, and the vessel qualifications are limited to automated i

exammation d vessel shell welds. There is only a handful of people qualified to perform manual examinst one of vessel shell welds. There are many welds that must be done manually. No personnel L (vendor or othenuse) have been qualified for nozzle inner radius or nozzle-to-shell weld examinations. No personnel have been qualified for dissimilar metal welds. All of these types of examinations are within the scope of Appendix Vill and would require implementaten.

The following is an example of the industry assessment needed to determine potential " actual" available qualified personnel should an expedited implementation be mandated:

The PDA has not issued nor has funding been provided to issue and maintain a qualif' ation c

matrix of PDI qualified personnel. If the number of " qualified" technicians is actually 300, this number must be broken down to identify the number of technicians that are available for use 6t multiple facilities (i.e. transient, vendor-employed technicians) and the specific PDI qualifications they possess. Conservatively assuming that 25% of these qualified technicians are currently employed by nuclear utilities would eliminate them from the pool of technicians available for transient owiAyirent. This would leave 225 examiners in the pool. Without a qualification matrix L

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' VERMONT YANKEE NUCLEAR POWER CORPORATION U. S. Nuclear Regulatory Commission

- BVY 98-54/ Attachment Page 2 of 4

.it is difficult to determine how many of these individuals would posses a full complement, or the I

applicable complement, of PDI qualifications. The fact is a significant number of candidates do not posses a full compliment of these qualifications. In today's industry environment it is important to acquire technicians who individually possess a broad range of qualifications in order to limit the administrative burden and labor costs by limiting the number of personnel required to perform a given scope of examinations. Conservatively subtracting even 25% of the remaining 225 techneians for this reason would leave only 169 available technicians for an outage season.

Adding IGSCC qualification and the 3-year limit on this qualification only diminishes the pool further.

The rulemaking must be limited to those Appendix Vill Supplements for whch procedures and an adequate number of personnel have been qualified. If these limitations were addressed, the industry would be ready to implement a qualification program within a reasonable time frame. The industry and the PDI are working on a plan for implementation of the other Appendix Vill Supplements, whch would be ready at a later date.

The NRC in the proposed rule (2.4.1.1.1,2.4.1.1.2, and 2.4.1.1.3) takes exception to three specific areas of the qualification process as implemented by the PDI and Appendix Vill.

2.4.1.1.1 Appendix Vill Personnel Qualifications One is the requirement that personnel must receive ten hours of annual training. The NRC states that an acceptable altemative would be to require 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> of annual training, whch would include practee on actual cracked specimens. We agree that practee on actual cracked specimens is valuable to maintain proficiency in ultrasonic testing The example that the NRC cites in 2.4.2 is a good one. Many personnel, after initially

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failing the PDI demonstration, pass on the second try wth no further trairwng However, we disagree that 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> of training or such practee is necessary. The proposed rule would also require that the training be split i

up throughout the year. There are very few utilities or vendors that have an adequate library of specimens for '

practme. This requirement would require travel to and from locations that possess such a specimen set several times a year, or the purchase or rental of such a speewnen set, eithar of which would be very expensive. Even though the examiner possessing it maintains the PDI qualification, the annual training performed will have to be documented and administered by the vendor and/or the licensee who employs the technician. Questions arise such as: Does a technician arriving on site having 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> of training for I

the current year (say 5 months into the year) satisfy the intent of the 40 hour4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> requirement or would an j

. additional 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> of training have to be performed prior to performance of examinations? This would -

i mean identifymg any provous training. verifying that this training is in compliance with the rulemaking j

(especially if it were performed by anvther vendor or licensee), and training each examiner if required. On the basis of the referenced studies supporting the proposed rule, showing a diminished capability within

' approximately 6 months, it can be extrapolated that a minimum of two (2) 20-hour training sessions -

annually would be needed to satisfy this requirement. An acceptable attemative is found in Code Case f.

N-583 that was passed by the ASME. This Code Case requires eight hours of practce on actual cracked i

specimens. This would still require either travel or purchase or rental of a specimen set. Requiring 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> of annual training is identified, as a significant additional burden with no recognized commensurate increase

- in quality.

2.4.1.1.2 Appendix Vill Specimen Set Cracks

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i The second exception that the NRC takes to the Appendix Vill rules involves the type of manufactured flaws in the qualification sample sets. The NRC would not allow the use of notches. The proposed rulemaking would require the PDI vessel and nozzle specimens to contain all cracks instead of a combination of cracks and notches. This could result in major logistical and financial impact to licensees who have j

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V'ERMONT YANKEE NUCLE /.R POWER CORPORATION -

U. S. Nuclear Regulatory Commiss'on -

i BW 98-54/ Attachment -

Page 3 of 4 reactor vessel weki examinations scheduled in the fall of 1998. The currently qualified vendors that could be utilized would not be qualified in accordance with the requirements of the rulemaking. It is also doubtful if specimens, let alone the funding, could be acquired in time to accommodate these examinations.

ASME is now wortung on a wi,yiviiiise to this' modification. There were many fewer notches used in actual -

qualificabons than are allowed by Appendix VHl. The new " Appendix Vlli Rewrite" Code Case would restrict the use of notches much further than in the onginal version.

However, there are a few instances where the use of notches is appropriate.~ When scanning from the clad surface of a vessel qualification specimen, notches were necessary to control the height of smaN flaws. The use of a notch in this circumstance would not enhance the reflectivity for detecton or sizmg because there would be no comer trap or specular reflection. AdditionaNy, it may be necessary to use notches in small

. diameter nozzles for inner radius samples, simply because there are no crack implantation techniques that are possible in such nozzles. Actually, the use of notches would not generaNy improve the delectability of '

these test flaws because the mqlor essential variable that is being qualified in Supplement 5 for nozzle inner radius examinahons is misorientation angle. As the misonentation angle increases, the reflectivity from a smooth notch would ':ecome worse than from a many faceted crack. Hence, cualific.".?sth a notch in this circumstance would be conservative.

2.4.1.1.3 Appendix Vill n+?c-Set Microstructure The third exception that 11 e NRC takes to Appendix Vlli is in specimen set microstructure. The NRC would -

require that au specimens for single-sided tests contain microstructure like the components to be inspected and flaws with non-ophmum charactenstics consistent with field experience that provide realetic d:"y -

. to the UT technique.

We agree with this modification. For piping and austenitic materials it has been shown that flaws that are -

. titled are more easily detected from one side than another, it is also true that austenshe wolds may inhibit sound travel throitgh the wold. However, we belove that the PDI is adequately aNowing for these differences, that the flaws' microstructure represents flaws actuaNy found in-service, and that the tests provide adequate dz"rges for ei,$ : died qualihcaton on peng samples.

We further belove that the flaws that have been used for the PDI vessel samples represent the '

microstructure of postulated inservice flaws in vessel welds. _ Flaws in carbon steel vessel welds are always postulated to grow perpendicular to the surface. Even if a flaw follows the fusion line of a weld prop surface (which it is not postulated to do) these fusion 'ines are almost always six degrees or less from the perpendcular. In that case, a flaw would not be approcebly more detectable from one side than another.

. The PDl specimens have flaws that are very close to perpendcular, the same as would be postulated from actua' inservice flaws.~ To manufacture addit' nal flaw specimens for vessel shou weld qualifications would o

be both unnecessary and an extreme financial burden.

Therefore, we beleve that, although this Appendix VH1 modificaton is necessary to control single-sided exammahon qualifications, the current PDI spacemens that have been used for vendor performance demonstratons most the intent of the modification and that the single-sided qualificatons that have been performed to date are valid.

A supplementary concem that is raised by these last two of the three proposed modifications is that some or aN of the five vendor vessel shell wold performance demonstrations that have been completed may become voided if PDl's implementation is not deemed acceptable. This would render the argument that the industry is ready to implement performance demonstration impotent.

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VERMONT YANKEE NUCLEAR POWER CORPORATION

. U. S. Nuclear Regulatory Commission BVY 96-54/ Attachment Page 4 of 4 ASME a'xt the PDI, with the support of the NRC, have developed an excellent program for qualification of ultrasonic examination personnel. The program does require further work, however it will be a major step forward in raising probability of detection and confidence in flaw sizing. The caveats that the NRC now wishes to append to the program will further delay this improvement, add significant cost burden, and add '

questionable value.

- We believe that a successful ultrasonic examination performance demonstration program can be implemented within a rossonable time frame. For this to happen, several key items must be resolved.

ASME must complete its rewrite of Appendix Vill which would satisfy the NRC's concem that the rule must be based on the Code.

The implementation must be phased Only the Appendix Vill Supplements that are ready at each

. juncture must be mandated.

The industry must convince the NRC that the reservations regarding maintenance of proficiency are unfounded and that the PDI specimens that have been in use now for five years are acceptable.

Otherwise, a more extensive backfit analysis relative to implementation of Appendix Vill may be necessary.

Closing The industry and the NRC must not lose focus on the intent of ASME Section XI and Appendix Vill and Appendix Vll. The purpose of pursuing a performance based demonstration approach to performing inspections at nucisar power facilities was to improve the quality and confidence of NDE activities. To this purpose we sought to identify the best equipme% 'ne best procedures, and inspection techniques, and the best personnel to perform the inspection was our objective to then raise the bar to a higher level of expected performance. This objective was accompished. However, the Code, as modified by the NRC proposed rule, could be observed to be raising the bar considerably higher without careful consideration of the cost benefit for this additional difference from the version of the program presented by the industry.

The shift in' requirements for personnel training and qualification, design requirements for test specimens, and the general conclusion that the industry is ready today to implement an Appendix Vill program as a result of PDI, places a huge additional burden on the industry without identifying a commensurate increase in quality in detecting flaws in our plant systems, it would appear that this issue needs to be considered, and if appropnate, a backfit analysis performed.

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