ML20082A344

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Responds to NRC Ltr Re Violations Noted in Insp Rept 50-443/91-12 on 910621.Corrective Actions:Performed Addl Reviews & Analyses of Radiographic Film for Subj Welds Using Code Acceptable Techniques
ML20082A344
Person / Time
Site: Seabrook NextEra Energy icon.png
Issue date: 07/08/1991
From: Feigenbaum T
PUBLIC SERVICE CO. OF NEW HAMPSHIRE
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20082A347 List:
References
NYN-91106, NUDOCS 9107100288
Download: ML20082A344 (71)


Text

__ --_ a New Hampshire l Ted C, Feigenbaum h h Presdent and Chief Laewthe Off aer 1

NYN 91106 J uly 8,1991 United States Nuclear Regulatory Commission Washington, DC 20555 Attention: Document Contru Desk RcIe rences: (a) Facility Operating License Nt . NPF-86, Docket No. 50-443.

(b) Public Meeting fic twee n ' dew llampshire Yankee and the NRC conducted on June 21,19f *

(c) NI-lY Letter NYN 91100 dated June 26,1991,

  • Request for Inspection.

Report and Clarification of Radiograph Quality issues," T.C. Feigenbaum to T.T. Martin.

(d) NRC Letter dated June 27, 1991, T.T. Martin to T.C. Feigenbaum.

(c) NRC Notice of Violation Regarding Inspection Report 50 443/41-12, dated June 28, 1991.

Subject:

Reply to Notice of Violation Regarding Inspection Report 50 443/91 12 C Gentlemen:

In the June 21,1991 Public Meeting between New ilampshire Yankee (NilY) and the NRC [ Reference (b)), the NRC requested that within two weeks, NilY provide a proposed corrective action plan that would respond to the inspection items which remained unresolved or unacceptable at the close of the public meeting. In a letter dated June 26, 1991

[ Reference (c)], NilY requested that this response be delayed until two weeks after receipt of the inspection Report in order to more thoroughly understand the NRC's concerns regarding these issues. The NRC responded to this request in a letter dated June 27,1991

[Refuence (d)), and granted NilY until July 8, 1991, to provide the subject response.

Subsequently, on June 28, 1991, NilY received Inspection Report 50-443/91-12 l Reference (e)].

Accordingly, enclosed please find NilY's Response to the Notice of Violation Regarding inspection Report 50 443/91 12. The enclosure provides NilY's basis for disputing the violation, describes the additional short term actions NilY plans to take, and transmits a technical explanation to address the one unresolved item regarding radiographic technique.

As discussed in the Enclosure, it remains our position that the subject welds comply with ASME Section til regarding weld quality and the subject radiographs comply with ASME Section / regarding film quality.

9107100288 91070s PDR ADOCK 0D000443 0 PDR s j New Hampshire Yonkee Division of PuHic Service Company of New Hampshire g g g t') { P.O. Box 300

  • Seabrook, NH 03874
  • Telephone (603) 474 9521 ,t y

9 t United States Nuacar Regulatory Commission J uly 8,1991 Attention: Document Control Desk Page two We recognize that qualified radiograph interpreters can, and occasionally do, reach different conclusions after viewing the same radiographic film. Not wit hst anding our conclusions regarding the Code acceptability of the subject welds and radiographs, NilY has taken the additional and conservative measure of digitiring these radiographs. The digitiration results have confirmed tne existence of visible density differentials at the location of the penetrameter holes that were previously observed by the Pullman liiggins, NilY, Yankee Atomic Electric Company (YAEC), and independent radiographic film reviewers.

The digitiration results demonstrate that the penetrameter holes are present and therefore are capable of being discerned in the original films. Also, as discussed in the Enclosure, it is our opinion that the use of non film radiograph imaging techniques is recognited under the Coac of record. 11ence, the films achieve Code compliance. NilY believes that this additional information, which had not been reviewed by the NRC inspectors at the time Inspection Report 50 443/91 12 was issued, is a valid and useful means for resolving differences in technical interpretation which may exist between different reviewers.

Furthermore, in an effort to be fully responsive to the NRC's concerns, and to eliminate any doubt regarding the quality of the subject welJs, NilY will: 1) perform raother rauiographic cxamination of the six welds for which the NRC has deemed the radiographic film to be unacceptable. It should be noted that NilY has previously committed to reradiograph weld 1 CS-318-02 F0202 in NilY letter NYN 91092, dated June 10, 1991; 2) review the film in accordance with our present program requirements; and 3) include the new radiographs and radiographic inspection reports in the N11Y records management system as a supplement to the existing Code acceptable radogral, hic records for these welds. NilY will complete these actions during the refueling outage currently scheduled to begin on July 27, 1991. It is expected that these results will be available by the end of August 1991.

NilY is fully committed to being comp!ctely responsive to any potential quality or safety concern identified during the review of weld radiographs and weld records. NilY will continue to strive to fully analyre all available and relevant information and to perform whatever actions are necessary to respond to quality or safety concerns to ensure there is no reduction in the level of protection provided fer the health and safety of the public. In this regard, New Hampshire Yankee has committed to a number of short term actions including: 1) rcradiographing the six welds addressed in the notice of violation,2) completion of the comprehensive Weld Record Reverification Program (WRRP) and reradiographing of any other welds identified as requiring rcradiography to resolve WRRp issues, 3) making radiographic digitization and evaluation results availabic to NRC inspectors. NilY believes that completion of these short term actions is necessary and important in oider to identify if any generic weld program issues remain to be addressed. Only after all the relevant facts are available and analyzed can generic implications be fully understood and any longer term actions be comprehensively developed and implemented. The results of all short term actions together with a detailed evaluation of generic issues will be submitted to the NRC in a written report by September 15, 1991.

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D 1 United States Nuclear Regulatory Commission July 8,1991 Attention: Document Control Desk Page thace Should you have any questions regarding this mattet, please contact me at (603) 474 9521, extension 4400.

Very truly yours, n

Enclosure i

ec: Mr. Gordon E. Edison, Sr. Project Manager i Project Directorate 1-3 I Division of Reactor Projects U.S. Nuclear Regulatory Commission Washington, DC 20555 Mr. Ebe C. McCabe, Chief j Reactor Projects Section ,

U.S. Nuclear Regulatory Commission j Region 1 ,

475 Allendale Road King of Prussia, PA 19406 Mr. Thomas T. Martin, Regional Administrator Region 1 475 Allendale Road King of Prussia, PA 19406 Mr. Kenneth E. Prockman Office of the Executive Director for Operations U.S. Nuclear Regulatory Commission 11555 Rockville Pike Rockville, MD 20852 Noel Dudley NRC Senior Resident inspector P.O.130x 1149 Scabrook, Nil 03874 Mr. Phil Joukoff United States Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596 Mr. Frank Forgione, Special Agent Office of the Inspector General United States Nuclear Regulatory Commission MNBB 6715 Washington, DC 20555 1

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t 1 New linmpshire Yankee July 8,1991 ENCLOSURE TO NYN 91106 RESI'ONSE TO NOTICE OF VIOI,ATION HEGARDING INSI'l:CTION REPORT 50 443/91 12 l

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, e HI:S PONSI: TO NOTICI: Ol' YlOI ATION IO:G AHlilNG INSPI:CTION Hl: PORT 50 44h9112 A. Introduction Thc following provides New flampshire Yankee's N!a .-sponse to the Notice of Violation for the six items considered unacceptable by the NF tc ding radiograph code compliance and the one item considered unresolved regarding radio,,. ,- technique, raised in Inspection Report 50 443/91 12 dated June 28, 1991. These issues we. ide<9ent by an NRC Level 111 Inspector in the May 29, through 31, 1991 Inspection, and ws ~ . .. .; 4 t o NilY in the June 21,1991 Public Mee*.;ng. The following provides NilY', be.: .< obut r s' the violation, and transmits a technical explanation to address the ote un eco%d m negarding radiographic technique.

B. llackcround NRC Inspection Report 50 443/91 12 describes six items as 'unaccepta51," and one item as ' unresolved.' Specifically, this report states that, based on the failure to obtain the proper image sensitivity in the penetrameters, the radiographs for the following weld 6 are considered to be of unacceptable quali*y: 1 CS 318 02 F0202; 1 CS 355 05-F0501; 1.CS 355-01 F0109; 1 CS 355 08-F0801; 1 CS 355 01 F0102 and 1 CS 302 04 F0404. The unresolved item pertains to weld 1 CS-360 02-F0206, where the radiographic technique utilized for the repair radiographs appeared to be different from the technique stated on the radiographic k inspection report.

Inspection Report 50-443/91 12 taises an additional issue not originally presented in the "NRC Synopsis of Radiographic Review at Seabrook Station 5/29 to 5/30.* The inspection report stated that "when a rereview of the radiottaphs lfor weld 1 CS 355 05 F0501] was performed on June 20, 1991 it was determined that the radiographs did not have sufficient 4T sensitivity

  • NiiY's position regarding the above mentioned issues is presented below.

C. Dois for Discutine the Violation for the Six Items Considered To lic Unacceotable By The NRC Recardinn Radior,rpoh OualitY

1. Radiographic Reviews c inducted During Construction Each of the six radiographs in question was reviewed ay a number of persons during tbc construction process. Each of these reviewers accepted the subject radiographs and therefore, each of them were able to discern the required 4T sensitivity. These persons included the original radiographer, the Pullman liiggins Level 11 reviewer, in some caser, an additional Pullman liiggins Lesel 11 or Level til icviewer, the Authorized Nuclear Inspector, the Yankee Atomic Electric Company (YAEC) Level !! reviewe r, and in some cases, additional Y AEC Level II or Level 111 reviewers. The number of reviews performed during the construction process was very consenative and exceeded the nu..iber required by the Code.

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2. Rereviews of Radiography NilY has condu,:ted a rereview of the =ix items considered to be unacceptable by the NRC. One Level 11 RT reviewer and three Level 111 RT reviewers evaluated these radiograph issues and determined that the subject welds comply with AShiE Section 111 for weld quality, sud the subject radiographs comply with ASME Section V for film quality.

This position was reffir.ned by N11Y at the Public hiceting of June 21, 1991. During the June 21,1991 Public hiceting, NilY provided the NRC with N11Y hiemoiandum (NOG

  1. 91358), dated June 17, 1991, " Response to NRC Synopsis of Radiographic Review at Seabrook Station 5/29 to 5/30," (aitached and marked "A*) The six radiograph quality issues, and one radiograph technique item presented in inspection Report 91-12 were discussed in this memorandum. At the same meeting, Mr. IIelmut Thielsch stated that he and his associate Mr. William Weseman, independent Level 111 RT reviewers, had each also reviewed the subject radiographs and that they had independently arrived at conclusions consistent with the overall NHY position. (See Thielsch Engineering Associates Inc. Report No. 4762, attached and marked *B').

Collectively, each of these reviewers involved with this rereview effort have multiple years of experience reviewing radiographic film. Each is a certified Level 11 or Level 111 reviewer. Two are Fellcws of the American Society of Nondestructive Testing (ASNT) and one of these individuals is on the ASNT Board of Directors. Two have no prior connection with NHY, Seabrook Station, or the radiographs in question. All six have certified that they discern the required 4T sensitivity in each of the subject racecgraphs.

As described above, inspection Report 50 443/91-12 raised an additional issue not presented in the NRC Synopsis of Radiographic Review at Seabrook Station 5/29 to 5/30.

NHY has evaluated this new issue and determined that it does not change the canctusion that the subject weld complies with ASME Section 111 for weld quality, and the subject radiographs comply with ASME Section V for ICm quality. The NHY evaluation of this new issue is contained in NHY Memorandum (NOG #91385), dated July 3,1991 (attached and marked "C").

3. Code Provisions ASME Section V, Paragraph T-261 provides the Code requirements for penetrameter sensitivity. Specifically, it states:

" Radiography shall be performed with a technique ci suf ficient sensitivity to display the penetrameter image and the specified hole, which are essential indications of the image quality of the radiograph. The radiographs shall also display the identifying numbers and letters "

The Code only requires that the 4T penetrameter hole be discernible to the qualified, certified reviewers assigned to review the radiographs.

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4. Digitization of Radiographs Notwithstanding NilY's conclusion that the subject radiographs are Code acceptable because they have been accepted by qualified, certified reviewers, NilY recognites that legitimate differences in technical interpretation can exist among qualified radiographic interpreters. These differences can be caused, among other things, by the natural variations in the capacities of different human beings to discern small differences in radiographic film densities. These different perceptions do not prove that one perception is " correct" and the other is " erroneous," but rather only that they differ. In an effort to be responsive to the apparent interpretation differences which exist between NHY and the NRC regarding the radiographs for the six subject welds, NilY has digitized the radiographic film for the six welds.

Digitization is a non film imaging technique which translates an analog radiographic film image into digital form, while maintaining the resolution and the dynamic ranges found on the analog film. Digitization only records the information contained on the original film; it does not add nor create any additional information that is not on the original film. The actual process of digitization is no 4nore complicated than reading consecutive, but very small, sections of radiographic film for density (i.e , darkness) by laser optical means, recording the analog results in digital form (i.e., assigning each reading the digital value associated with the range of densities capturing the laser optically determined density of the pixel in question), and then displaying the digitally recorded information on a monitor. The digitized image demonstrates that the image of the penarameter hole is in fact present on the original film, and digitization is capable of confirmin3 the original determinations of the Licensee interpreters who saw the 4T hole unaided.

NHY has digitized the radiographic film for the six subject welds and the results have substantiated the Code acceptability of the NHY and YAEC determinations. These determinations were exclusively based on the original radiographic film.

Although NHY is not utilizing the digitized images as the Code radiographs of record, the ASME Code of record (1977 Edition, Winter of 1977 Addenda) does not prohibit the use of imaging techniques in the radiographic interpretation process. Specifically, ASME Section V, Subsection B, Article 22, " Standard Method for Controlling Ouality of Radiographic Testing, SE-142," recognizes alternate non-film imaging techniques as follows:

"The use of non film imaging techniques will be permitted provided that the applicable penetrameter hole is demonstrated in the resultant image."

In addition, the ASME Code of record,Section XI, Paragraph I W A- 2231, also recognizes the use of non film imaging techniques as follows:

" Radiographic techniques, employing penetrating radiation such as X-rays, garnma rays, or thermalized neutrons, may be utilized with appropriate image-recording devices such as photographic film or papers, electrostatic systems, direct image orthicons, or image converters."

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- Moreover, the use of digitization has also been approved by the NRC_ for the storage

. of quality assurance records, Specifically, NRC Generic Letter 8818, " Plant Record Storage on Optical Disks," was issued by the NRC to " inform addressees that the staff approves the-use of this method of record keeping [ optical disk document imaging systems for the storage and retrieval of record copics of- quality assurance records] when appropriate quality-assurance controls are applied.' The requisite quality assurance measures' pertain to the ability to digitally preserve the information contained on the original film.

flased on tlye foregoing a.nalyses of the issues considered unacceptable by the NRC, analysis of the Code requirements, and the results of the digitization process, NHY reaffirms its conclusion that the subject welds comply with ASME Section III for weld quality, and the subject radiographs' comply with ASME Section V for film quality.

D. Resolution of Unresolved item Recardine Radiocraohic Techniaue

'NHY har rereviewed the NRC's concerns regarding the apparent discrepancy between the radiographic technique utilized for the repair radiographs for -weld 1 CS 360 02 F0206, and the technique stated on the radiographic inroection report. This rereview has reaffirmed NHY's original position, that all radiographs for this weld were in fact produced utilizing the technique stated on' the radiographic inspection report. The results of this rereview, and a more detailed explanation to support our position regarding this unresolved item, is provided in the NHY Memorandum (NOG #91386), dated July 3,1991 (attached and marked *D*).

~ NHY believes that- this explanation will close out the unresolved item concerning this weld.

E. Corrective Steos that Have Been Taken and tne Results Achieved 1

As provided above, NHY has performed additional reviews and analyses of the l radiographic film for the subject we:ds and has concluded that it is not necessary to perform additional corrective steps at this time. These additional analyses have confirmed the results of the original radiographic reviews, in that the subject welds comply with ASME Section 111 for weld quality, and the subject radiographs comply with ASME Section V for film quality, F. Corrective Steos that Will be Taken to Avoid Further Violations

, As' provided above, NHY has performed additional reviews and analyses of the _

radiographic film for the subject welds using code acceptable techniques. These additional analyses have cv. firmed the results of the original radiographic reviews, in that the subject

- welds comply with ASME Section 111 for weld quality, and the subject radiographs comply with ASME Section V for film quality NHY will take the actions necessary to make the digitization lab available to NRC ins. .ctors to facilitate final resolution of the issues of concern upon NRC request.

Notwithstanding this, in addition to the digitization process, in un effort to be

- conservative, fully responsive to the NRC's concerns, and to eliminate any doubt regarding the quality of the subject welds, NHY will: 1) perform another radiographic examination of the six welds for which the NRC has deemed the rad' agraphic film to be unacceptahic. It should be noted that NHY has previously committed to reradiograph weld 1-CS-318

  • F0202 in NHY letter NYN 91092, dated June 10, 1991; 2) review the film in accordance with t

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4 our--present program requirements; and 3) include the new radiographs and radiographic inspection reports in the NilY records management system as a supplement to the existing Code acceptable radiographic records for these welds. Nil Y will complete' these actions j during the refueling outage currently scheduled to begin on July 27, 1991. It is expected . l that the results of this effort will be available by the end of August 1991.  !

l NHY has evaluated the NRC's concerns regarding the six weld radiographs at. issue 1 and has concluded that, since no deviations from the Code or applicable procedures have l been detected, insufficient information exists to perform a generic implications analysis at this - time. As stated above, New- liampshire Yankee has - committed to a number of -

short term. actions. including: 1) rcradiographing the six welds addressed in the notice of violation,2) completion of the comprehensive Weld Record Reverification Program (WRRp) and reradiographing of any other welds identified as requiring reradiography to resolve WRRP issues, 3) making radiographic digitization and evaluation results available to NRC inspectors.- NiiY believet that completion of these short term actions is necessary and I important in-order to identify if any generie weld program issues remain to be addressed. .

Only after all the relevant facts are available and analyzed can generic implications be fully understood and any longer term actions be comprehensively developed and implemented. The results of all short term actions together with a detailed evaluation of generic issues will be

- submitted to the NRC in a written report by September 15, 1991.

G. Date When Full Comoliance will be Achieved This is not directly applicable as the subject welds comply with ASME Section til for weld quality, and the subject radiographs comply with ASME Section V for film quality.

However, as stated above, NiiY has already completed the digitization analysis, and has committed to rcradiograph the six subject welds-during the refueling outage.

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New llampshire Yankee July 8,1991 ATTACHMENT A

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-- ______=________-_-_.

NoE Hampshire d MEMORANDUM SQG#91358 SSP #910292 SU BJ ECT: RESPONSE TO NRC SYNOPSIS OF RADIOGRAPHIC REVIEW AT SEAllROOK STATION 5/29 TO 5/30 FROM: R.C. J ulian DATE: June 17,1991 T.R. Frolo TO: File Attached are responses to :he weld radiograph issues raised by M.C. Modes, NRC RT reviewer, in the " Synopsis of Radiographic Review at Seabrook Station 5/29 to 5/30." This radiographic review pertained to selected Pullman Higgins field welds.

As provided in the Attachment, NHY has determined that the subject welds comply with ASME Section 111 for weld quality, and except for one weld (1 CSM18-02 F0202), the subject radiographs comply with ASME Section V for film quality. As stated in the Attachment, review of the radiographs for weld 1-CS-318-02-F0202 indicated that the comparative densities of the penetrameters to those in the weld area of interest exceed the density limitation ranges specified by the Code. This discrepancy does not preclude the ability to make an evaluation of this weld for unacceptable indications per the Code requirements. The individual densities of both the penetrameters and the weld area of interest, in conjunction with the sharpness and clarity exhibited on the radiographs, are such that indications would not be masked.

The issues raised do not call into question the physical quality of any of the subject welds or other Seabrook Station welds. These issues do no' compromise the integrity of :he systems in which these welds are located, and thus they do not produce any reduction in the protection provided for the health and safety of the public.

This memorandum will be referenced on the film jackets of the respective welds.

\OddC -kw R.C. Julian NHY RT Level 11 h

T.R. Frolo NHY RT Level !!!

Concurrence: /

P. Oikle, RT Level 111, YA EC S. VMk, RT L'evel 111, YAEC l

New Hampshire Yankee Division of Public Service Company of Nw Hampshire l P.O. Box 300

  • Seabrook, NH 03874
  • Telephone (603) 4769521

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RESPONSE TO NRC SYNOPSIS OF RADIOGRAPIIIC REVIEW AT SEAllROCK STATION 5/29 TO 5/30 The following provides responses to the weld radiograph issues raised by M.C. Modes, NRC RT Reviewer, in the " Synopsis of Radiographic Review at Seabrook Station 5/29 to 5/30." This radiographic review pertained to selected Pullman-Higgins field welds at Seabrook Station. Presented below are the issues as provided by the NRC in their Synopsis, I and the NHY response. The NHY review of these issues was performed by an RT Level 11 and an RT Level til reviewer. Additionally, two RT Level !!! reviewers from Yankee Atomic j Electric Company (YAEC) also reviewed the subject radiography and concurred with the l responses provided in this report.

It has been determined that the subject welds comply with ASME Section !!! for weld quality, and except for one weld (1 CS-31S 02 F0202), the subject radiographs comply with ASME Section V for film quality. As stated in this response, review of the radiographs for weld 1 CS-318-02 F02C2 indicates that the comparative densities of the penetrameters to those in the weld area of interest exceed the density limitation ranges specified by the Code.

This discrepancy does not preclude the ability to mak: en evaluation of this weld for '

indications per the Code requirements. The individual densities of both the penetrameters and the weld area of interest, in conjunction with the sharpness and clarity exhibited on the radiographs, are such that indications would not be masked.

The issues raised do not call into question the physical quality of any of the subject welds or other Seabrook Station welds. These issues do not compromise the integrity of the systems in which these welds are located, and thus they do not produce any reduction in the protection provided for the health and safety of the public.

1 CilS 120101 F0103 Issue "This weld had internal undercut of some severity with a possible lack of penetration and/or severe root concavity (suck-back). Although this weld package had been reviewed up to and including the YAEC Level III none of the above indications were noted on the report. The indications were not evaluated or disposed of.'

Remonse On May 30,1991, NHY Nuclear Quality Group (NOG) personnel performed a rereview of the radiographic package and weld process sheets for Pullman-Higgins field weld 1-CBS.

1201-01 F0103. This weld package contains radiographic film for four stations (i.e., stations 0-1, 1-2, 2-3, and 3 0). The radiographic film for station 12 indicates the presence of minor, code allowable root concavity. The film for station 2-3 also indicates the presence of minor, code allowable root concavity and minor, code allowable centerline shrink. The film for station 3-0 indicates the presence of code allowable tungsten inclusions and an artifact (roller mark) which does not interfere with interpretation of this film. Rereview of the film for all stations indicates that there is no evidence of lack of penetration or internal undercut in this weld. The process sheets for this weld state that a post weld visual examination of the internal weld surfaces was performed fce this weld on December 17, 1979.

The examination attributes were for oxidation, concavity, convexity, undercut, and unconsumed 1

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insert, and in all instances were fourd to be acceptable for this weld. The process sheets for this weld were not reviewed by the NRC at the time of their 5/29 and 5/30 inspection of radiographic film.

As recognized in the NRC Synopsis, the above stated code allowable indications were not noted on the Radiographic Inspection Report (RIR) for this weld. Additionally, there is no further documentation which addresses these code allowable indications. This documentation, however, is not required. There are no Code provisions which require documentation of, or disposition of wcld indications which are allowable by code. This is consistent with interpretatiou V-77-06 of ASME Section V, T-292, Evaluation by Manufacturer. Specifically, this int >:r pret ation addressed the question of whether T-292 requires Code acceptable flaws or defects to be recorded or documented by the manuincturer. The interpretation stated:

'[ilt is the intent of T-292 of Section V that it requires that the record of the radiograph of materials showing acceptable flaws, discontinuities, etc. need only lig the radiograph as being acceptable. It is not interptr.t ed as requiring tbc documentation of individual Code acceptable flaws or indications."

Based on the foregoing, Pullman Higgins field weld 1-CBS 1201-01-F0103 complies with ASME Section til for weld quality, and ASME Section V for film quality.

To facilitate future review of radiographs by contracted RT reviewers, NilY is in the process of preparing a procedure that describes how the review is to be conducted and documented.

1 CS-355 05 F0501 issue "The 0 cxposure was rejected by a YAEC quality audit for lack of sensitivity in the penetrameter. There is no signature of concurrenc,e on the OA report and it appears that YAEC accepted the weld radiography before the 0 section was reshot for compliance with the OA finding. This appears to be the case as :hcre is no clear YAEC signature on the 0 reader sheet."

Response

The radiographic film for station 0, repair No.1 of this weld was rejected by a YAEC quality audit for lack of sensitivity in the penetrameter. This finding was documented in YAEC Seabrook Audit Report No. SA565CS184 which addressed the audit conducted from November 30, 1981 through December 10, 1981. This audit was conducted by a YAEC RT Level 111 reviewer. As a result of this finding, station 0 was reradiographed on December 1, 1981. As stated in the YAEC audit report, the radiograph for this reshot was reviewed and found acceptable by YAEC on February 12, 1982. Based on this, YAEC did not approve the reshot of this station before the radiograph was taken.

Based on the foregoing, Pullman Higgins field weld 1-CS 355-05-F0501 complies with ASME Section til for weld quality and its radiographr. comply with ASME Section V for film quality.

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1 CS.355 01 l'0109 I .

Issue "The final repair exposure lacks the required penetrameter sensitivity since the penetrameter and its shim was projected under the radiographic isotope fixture. This obscures the penetrameter to a degree that the required 4T sensitivity is not there."

Fesponse A tereview was conducted of the radiographic film for station 1, repair 1, of this weld. Irrespective of the placement of the shim and penetrameter under the isotope fixture, the required 4T sensitivity can be discerned on the penetrameter at the edge of the fixture's projection. The density of the penetrameter adequately covers the density of the weld repair area, via the three sides of the penetrameter that are visible.

On June 5,1991, the film for station 1, repair 1, of this weld was digitized to further confirm the information contained on the film. Review of the digitized film substantiates that the required 4T sensitivity is present irrespective of the isotope fixture's placement.

Based on the foregoing, Pullman liiggins field weld 1 CS 355 01-F0109 complies with ASME Section ill for weld quality and its radiographs comply with ASME Section V for film quality.

1 CS 3SS-01 F0104 issue "The flash identification has been climinated by exposing it without appropriate clocking. The identification was hand written in grease pencil. This is not a permanent identification of the film.'

Response

Rereview of the radiographic film for this weld it dicates that the flash identification block is discernable on the film for all three stations. The film for stations 1-2 and 2 3 contain the appropriate flash identification block information which can be viewed through the film viewer. The flash block on the film for station 01 was apparently exposed without appropriate blocking such that the identification information does not project through the radiographic image when it is viewed on the film viewer. Ilowever, all of the flash block identification information is permanently captured in this film's ernuision, and can be viewed as a reverse image on the back side of the film when it is exposed to reflected light. As a result, the film identification complies with ASME Section V, Article 2, paragraph T-236.

This same film also has the flash block information written in grease pencil to facilitate reading.

NHY has documented this occurrence in Corrective Action Request (CAR)91-019.

NHY has determined that the appropriate short term corrective action for this occurrence is to permanently identify the code required information on the station 0-1 film for clarity as a supplement to the same information contained in the emulsion.

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Additionally, NES Procedure 83A5642, Procedure for the Review of Radiographs, has

-been revised to indicate that any non permanent identification markings on radiographic film are= not acceptable ~ and are to be noted in the

  • remarks box" of the data sheet. This procedure roodification will ensure that any other occurrences will be brought to NHY's attention.

Based on' the fc . going, Pullman-liiggins field weld 1-CS 355-01-F0104 complies with ASME Section til for weld quality and its radiographs comply with ASME Section V for film quality.

1 CS 360-n2 F0206 issue "After a series of film rejections for a lack of sensitivity and unsharpness an acceptable radiographic series was generated, This allowed the determination of rejectable slag indications. The repair radiographs were not taken consistent with the technique stated on the radiographic reader sheet since the tangent wall of the pipe and weld is clearly 1 visible. The stated technique was double wall eccentric from the O.D. The only way that l the tangent wall can be revealed in a radiograph is if the source is positioned away from 1 the pipe wall." i

Response

The technique used to radiograph this weld was double wall contact, single wall viewing. This-is the technigr stated on the radiographic inspection report. With this technique, the source is placed on the outside diamster of the pipe wall while the film is wrapped around the lower portion of the pipe extending film coverage to more than 180

  • With this; technique it is possible for the film to capture the tangent wall of the pipe and l the weld. Rereview of the radiographs for this weld indicates that the area on either side of the weld area of interest appears eccentric. This is due to the weld transition from the

= pipe to the valve and the wrapping of the film tightly around the weld.

Rereview of the May 5,1982 radiographic film for station 2 of this weld indicates that l there was a slag indication in this view. Subsequent radiography performed on January 5, i

1985, utilizing a different technique, also revealed code rejectable slag indications in stations 3 4. and 4-0.- in the vicinity of station number 4. Subsequent repairs to this weld were successfully performed as documented on the RIR and the weld process sheets. The final weld was reradiographed on January 10, 1985, and the films for all stations of this weld were acceptable.

Based on the foregoing, Pullman Higgins field weld 1-CS 360-02 F0206 complies with ASME Section III for weld quality and ASME Section V for film quality.

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1 CS 432 02 F0203 lssue "The radiographic sections 1-2 and 0-4 show a lightened area typical of insufficient back scatter protection. In the 0 4 section the area of back scatter is impinging on the area of interest in the weld."

Response

Rereview of the radiographic film for this weld indicates that the film for station 1-2 had sufficient shielding to protect against backscatter. This is substantiated by the fact that a lead letter "B" is not visible in this view. The film for station 4 0 shows a light area in a small portion of the area of interest, but similarly, this is not caused by backscatter since the lead letter "B" is not visible in this view. Comparison of the light portion of the area of interest at station 4 in view 4-0, and the lighter #12 penetrameter was conducted.

The films indicate that 4T sensitivity is achieved and the density of the light area, at station 4, is covered by the densities on the lighter #12 penetrameter. The dark penetrameter, which also exhibits 4T sensitivity, covers the other portions of the weld.

Based on the foregoing, Pullman Higgins field weld 1 CS 432 02 F0203 complies with ASME Section III for weld quality and its radiographs comply with ASME Section V for film quality.

1-CS 355 08 F0801 1ssue "The penetrameters have been placed on a code tag. The 4T of the 12 penetrameter een ' sot be ser.n since. What clearly can be seen is the 'N' stamp on the code tag. The alternate 12 penetrameter shows no sensitivity as does the 15 penetrameter on the opposite side of the weld. On exposures 1 and 2 the light 12 penetrameter shows no sensitivity as the tag rolls around the series and blocks various shots."

Response

Rereview of the radiographic film for this weld indicates that 4T sensitivity is discernable on the #12 penetrameters for all three stations (0,1, and 2). While the presence of the code name plate can be detected, it does not obscure the penetrameters to the extent that 4T sensitivity can not be determined.- Similarly, the #15 penetrameter also achieves the required 4T sensitivity.

On June 5, 1991, the film for this weld was digitized to further confirm the information contained on the film. Review of the digitized film substantiates that the required 4T sensitivity is present on all films.

Based on this review, weld 1-CS-355 08-F0801 complies with ASME Section III for weld quality and its radiographs comply with ASME Section V for film quality.

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1 CS 355 01 l'0102 issue

  • The reader sheet has a statement: 'the source could not be lined up exactly over 0 due to the location of the joint.' This would be acceptable variation from the code [if) other exposures had been made to obtain 100% coverage. Of the three film [s] for the 0 location two have the flash ID placed directly over the penetrameter identification numbers, Thus these film [s] are not in code compliance and can not be used for interpretation of the weld acceptability. The third film does not have this problem. It does not have the required sensitivity for the penetratucters. Exposure 1 (next one in sequence), is too dark to show any sensitivity in the penetrameters. The shim on the 12 penetrameter was staggered in such a manner as to obliterate the outline of the penetrameter. The last exposure (#2) has marginal, but acceptable sensitivity in the penettameter representing the base metal but no sensitivity in the penetrameter representing the weld metal."

Resnonse Rereview of _ the radiographic film for this weld indicates that for station 0, the first two of three films (this film was triple loaded) have the flash identification block placed directly over the #12 and #15 penetrameter identification numbers. The required 4T sensitivity is exhibited on the #12 penetrameter in the first film for station 0. Similarly, the #12 and #15 penetrameters in the second film for station 0 exhibit the required 4T sensitivity. The iniage density in the #12 penetrameter for this film adequately covers the density in _ the weld area of interest. In the third film for station 0, the penetrameter identification numbers are not blocked by the flash identification block. This film does not exhibit the required 4T sensitivity for the #15 penetrameter, but does exhibit the required 4T sensitivity for the #12 penetrameter. This is adequate to establish acceptability of this weld and its radiograph.

Notwithstanding this, it is also possible to show a direct relationship between the films for all three-stations to provide a positive identification of the unlabeled penetrameters in the first two films. Examination of all three films for station 0 reveals that there are minor code allowable indications of tungsten present in the weld so as to provide a unique identifier among the exposures. Based _on comparison of the locations of the penetrameters in the first two films with that of the penetrameters in the third film, we are able to identify the unlabeled penetrameters in the first two films.

Rereview of the film for stations 1 and 2 indicates that the required 4T sensitivity was achieved, and the image densities cover the weld area of interest. Correspondingly, the technique utilized to radiograph this weld was acceptable by code since, as demonstrated above, there is 100 percent coverage of this weld.

Based on the foregoing, Pullman Higgins field weld 1-CS 355-01-F0102 complies with ASME Section 111 for weld quality and its radiographs comply with ASME Section V for film quality.

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1 CS 303 03 F0301 hlE.

"This is another example of a code tag being directly in the way of the penetrameter placement. The penetratueters do have acceptable but marginal sensitivity despite the obstruction."

R e s p ons e, Rereview of the radiographic film for this weld indicates that a code data nameplate is not discernable at or near the penetrameter. The rereview, however, does show that

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penetrameter identification. numbers are discernable and the required 4T sensitivity was achieved. It is conceivable that the counterbore adjacent to the weld may have been interpreted by the NRC reviewer as the edge of a code nameplate.

Based on the foregoisg, Pullman Higgins field weld 1 CS 303-03 F0301 complies with

' ASME Section !!! for weld quality and its radiographs comply with ASME Section V for film

. q uality.

1.CS 302 04 F04.qi Issue "Another example of code label in the way of the penetrameter placement. In this case however the sensitivity was not obtained for the #10 penetrameters representing the weld metal on any of the exposures."

Response

Rereview of the- radiographic film for this weld indicates that irrespective of the location of the code nameplate, the required 4T sensitivity was obtained and is discerne le on the' #10 penetrameters for all exposures. The #10 penetrameters adequately represent the weld metal.-

On June 5, 1991, - the film for this weld was digitized to further confirm the information contained on the film. Review of the digitized film substantiates that the luired 4T sensitivity is present on all films.

-Based on the foregoing, Pullman Higgins field weld 1-CS 302-04-F0404 complies with ASME Section III for weld quality and its radiographs comply with ASME Section V for film quality.

1 CS 318 02 F0202 l

l h1E.

"The radiographic reader sheet calls for the use of a composite view of the weld and a single view for the base material. There were three exposures taken for this wcid. In the t

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i first view, one of the two films used for composite viewing, has artifacts in the weld. Thus when looking at the weld in composite one can not be sure if a defect is being viewed [or]

if it is a film artifact. lu addition there is no 4T sensitivity in the penetrameter. The second exposure can be evaluated by composite, but again there is no 4T sensitivity.

Although the reader sheet records a double wall eccentric exposure and the first two sections are shot in this manner, the last view has been shot as an elliptical and can not be viewed composite. The density of the 3rd exposure is around 3.2 H&D single film."

Response

The technique used to radiograph this weld was double wall superimposed exposure, with two films taken of each of this weld's three statons. This is the technique stated on the Radiographic Inspection Report (RIR). All three stations of this weld were taken in this manner; none of the films of this weld were shot as elliptical views. It should be noted bowever, that there is a weld adjacent to 1-CS 318 02 F0202 which also appears on the film.

Since the source was directly aligned with F0202, and hence located off center with respect to the adjacent weld, the resultant view of the adjacent weld is elliptical.

All three stations of weld F0202 are to be viewed as a composite of the two films.

Review of the film for the first station indicated the presence of artifacts (felt pen ink residue from overlay duplication) on the film. These artifacts have been removed from the film and it has been confirmed that there are no defects or indications in this weld.

Additionally, the required 4T sensitivity is exhibited in this station's penetrameter.

Similarly, review of the film for the second station indicates the required 4T sensitivity is achieved. Review of the film for the third station indicates that the required 4T sensitivity was also achie ed.

The density through the body of the penetrameters meet the requirements of ASME 5ection V, paragraph T-234 The weld area of interest in each film also meets the density requirements of the same Code provisions. During the review it was also revealed, however, that the comparative densities of the penetrameters to those in the weld area of interest exceed the minimum / maximum density limitation ranges specified in ASME Section V, paragraph T-263.2. Specifically, the densities through the weld area of interest are 2.50 to 3.52 H&D. This technique shortcoming does not in itself preclude the ability to make an evaluation of the weld for enacceptable indications per the radiographic acceptance standards of NC-5320. As stated above, the densities in the weld area of interest are within the Code requirements of 2.0 to 4.0 H&D. Additionally, the sharpness and contrast of the radiographs are such that unacceptable indications would not be masked. Review, evaluation sad interpretation of the weld area revealed no Code rejectable indications. These findings are consistent with the findings of previous evaluations and the findings provided on this weld's RIR.

Furthermore, the process sheets for this weld document that a post weld visual examination of the internal and external weld surfaces was perforn ed for this weld on October 22, 1981. The internal examination attributes were for oxidation, concavity, convexity, undercut, and unconsumed insert, and in all instances were found to be acceptable for this weld. The external examination attributes included weld reinforcement, arc strikes, undercut, transition, purge dam removal, and suitability for NDE, and in all instances were found to be acceptable for this weld.

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On June 5,1991, the film for all stations of this weld were digitized to further confirm the information contained on the film. Review of the digitized film verifies that there art no indications or defects in the weld arer. of interest, and that the required 4T sensitivities were achieved on all films.

Based on the foregoing, Pullman liiggins field weld 1-CS 318-02-F0202 complies with ASME Section til for weld quality and except for one minor provision of the Code, its radiographs comply with ASME Section V for film quality. Notwithstanding this, 't has been .

determined that this weld does not contain any Code unacceptable indications. The NRC was notified of this anomaly on June 7,1991, and a written report regarding the same was transmitted via NilY 1.ctter NYN-91092, on June 10, 1991.

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- New Hampshire Yankee July 8,1991 t

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