A97014, Responds to RAI Re Third Interval ISI Relief Request CR-13 & New Relief Request CR-23
| ML20210L356 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 08/13/1997 |
| From: | Mueller J COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| ZRA97014, NUDOCS 9708210097 | |
| Download: ML20210L356 (17) | |
Text
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'l el 8 ("' 46.'OM i ZRA97014 August 13,1997 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Attn: Document Control Desk 1
Subject:
Zion Nuclear Power Station, Units 1 and 2 Third Interval Inservice Inspection Response to Request for AdditionalInformation NRC Docket Nos. 50-295 and 50-304
References:
- 1) Letter from L.11 olden, Commonwealth Edison, to U. S, Nuclear Regulatory Commission, dated March 1,1996; Forwarding ISI program Relief Requests CR-13, Revision 1 and CR-23
- 2) Letter from C. Shiraki, NRC, to D. Farrar, Commonwealth Edison, dated May 23,1996, Request for Additional Information Regarding 131 Program Relief Requests CR-13, Revision I and CR-23
- 3) Letter from T. Simpkin, Commonwealth Edison, to U. S, Nuclear Regulatory Commission, dated June 20,1995, Infonnation Pertaining to the Third Interval Inservice Inspection Program
- 4) Letter from R. Capra, NRC, to D. Farrar, Commonwealth Edison, dated September 1,1995, Safety Evaluation of the Third Interval Inservice Inspection Program and Associated Relief Requests This letter provides Commonwealth Edison's (Comed's) response to an NRC Request for AdditionalInformation (RAI).
Comed submitted, via Reference 1, a proposed Revision I ofInservice Inspection Program Relief Request CR-13, and a new Relief Request, CR-23. In Reference 2, the NRC requested additional information concerning the proposed revision and the new relief request. Comed's response to the NRC RAI it enclosed with this letter. As indicated in the enclosure, Comed is proposing additional changes to Revision 1 of Relief Request CR-13 and to Relief Request CR-23. The changed reliefrequests are provided as Attachments 1 and 2 respectively, and are to replace those submitted via Reference 1. A,/
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. ZRA97014, Page 2 of 2 Please direct any questions you may have concerning this submittal to this office.
. - Respectfully, o I Y.
J. H. Mueller Site Vice President
, Zion Station i
Enclosure Attachments
~
cc: NRC Regional Administrator - RIII Zion Station Project Manager - NRR -
Senior Resident Inspector - Zion Station i
Office of Nuclear Facility Safety - IDNS IDNS Resident Inspector L Zion NLA Master Files Reg. Assurance File DCD Licensing i-
\ ZRA97014 Enclosure RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION DATED MAY 23,1996 NRC Ouestion 1:
4 How does Revision 1 of Relief Request CR-13 relate to the original approved version of Relief Request CR-13? Do the original specific alternatives still apply? Will Case N-533 be implemented in its entirety (i.e., will all the subject bolted connections be examined with the insulation removed during the cold shutdowns)?
Comed Response to Ouestion 1:
Revision 1 of Relief Request CR-13 is intended to replace rather than supplement the original relief reguest (Reference 3) as modified by the SER (Reference 4). Therefore, the specific alternatives of the original relief request and the SER will no longer apply.
The reference to Lode Case N-533 was included in the originally proposed Revision 1 for information only. The alternative requirements being proposed are those stated in Revision 1 of the Relief Request, not those stated in the Code Case. In order to eliminate confusion, the proposed Revision I to Relief Request CR-13 has been changed to eliminate reference to Code Case N-533.
The proposed Revision 1 to Relief Request CR-13 has also been changed to clearly state that the removal ofinsulation and VT-2 inspection ofdepressurized bolted connections applies only to joints with removable insulation, and to add requirements that ensure evidence of previous leakage is not lost prior to inspection. At Zion Station, removable and non-removable insulation is to be defined as follows:
Removable insulation is stainless steel reflective insulation with Quick release buckles.
(This insulation is found on the Reactor Coolant System and the Class 1 portions of the Safety Injection system and the Residual Heat Removal system. )
Non-removable insulation is Calcium Silicate or fiberglass insulation banded in place and covered with an aluminum jacket that is secured by metal banding or sheet metal screws. (This insulation is installed on the Class 2 portions of the Safety Injection system, Residual Heat Removal system and the Chemical and Volume Control system.)
Finally, the proposed Revision I to Relief Request CR-13 has been changed to include Class 2 components for consistency with ASME Section XI,1989 Edition, IWA-5242, which does not distinguish between Class 1 and 2 systems that are borated for the purpose ofcontrolling reactivity. Accordingly, the proposed Revision I to Relief Request CR-13 has been changed to include Category C-H along with Item Numbers C7.10 through C7.80. The proposed Revision I to Relief Request CR-13 has also been changed to be more specific regarding the delay in reaching cold shutdown that would result from removal ofinsulation.
Page1of5
\ ZRA97014 Enclosure The currently proposed Revision 1 to Relief Request CR 13 is provided as Attachment 1 to this letter, Revision bars in the right margin indicate the changed portions of the text.
NRC Ouestion 2:
What are the specific components to which Relief Request CR-23 will be applied? What are the expected amounts of examination coverage anticipated for these components?
What is the total number and sample size for all such integral attachments?
Comed Response to Ouestion 2:
A Relief Request CR-23 will be applied to item Numbers C3.10, C3.20, C3.30, Categc,ry C-C, of Table IWC-2500-1, which have inspection limitations.
4 Currently ten specific components have been identified to which Relief Request CR-23 will be applied. However, as described below, Comed estimates that approximately 43 additional Unit I components and 40 additional Unit 2 components will require application of Relief Request CR-23 in the future.
The currently identified specific components to which Relief Request CR-23 will apply, and the amount of examination coverage for each are provided in Table i below. This table provides a listing of the integrally welded attachments that have been examined to-date during the ISI Third Interval and found to have limited access. (No Unit 2 integrally welded attachments are included in the table because none of those inspected thus far in the Third Interval have had limitations.) The proposed ReliefRequest CR-23 has been changed to include Table 1, along with associated changes in the text. Additionally, the sketches showing typical configurations that result in inspection limitations have been redrawn for clarity.
TABLE 1 LIMITED COVERAGE EXAMINATIONS 4
ON UNIT 1 INTEGRALLY WELDED ATTACHMENTS J
ATTACHMENT / SUPPORT SURFACE EXAMINATION NUMBER COVERAGE ACHIEVED CWE-2-2100-1/H05W 66 %
- CWE-2-2100-1/H10W 48%
1 CWE-2-2100-2/H17W 60 %
CWE-2-2101/H02W 90 %
CWE-2-2200-1/H05W 93 %
CWE 2-2200-1/HMW 59 %
CWE-2-2200-1/H07W 59 %
CWE-2-2200-1/H08W 38 %
CWE-2-2200-2/H14W 87 %
CWE-2-2200-2/H15W 60 %
Page 2 of 5
- \ ZRA97014 Enclosure The station ISI database indicates that there are 170_ Class 2, Category CC, Item 3.10, !
3.20, and 3.30 integrally welded attachments in Unit 1, and 161 such attachments in i
! Unit 2. Based on the number of these attachments that are of the same type as the 10 ^!
[ ' identified in Table 1, Comed estimates that approximately 25% of the attachments will i have some degree ofphysical constraint which would inhibit surface examinations, and therefore require the application of Relief Request CR-23 in the future. The 25% equates to 43 Unit I components and 40 Unit 2 components.
l Accordingly, the proposed relief request has been changed to clearly indicate that - ,
- integrally welded attachments with limited accessibility identified in the future will be i
, treated in the same manner as the 10 integrally welded attachments identified in Table 1. ;
- 4
[ Proposed Relief Request CR-23 has also been changed to include item numbers C3.10
- and C3.30 so that the relief request encompasses the Table IWC-2500-1 items that have o integrally welded attachments at Zion Station. The currently proposed relief request is provided in Attachment 2 to this letter, with the above described changes indicated by
} revision bars in the right margin.
, The current sample size for Class 2, Category CC, item 3.10,3.20, and 3,30 integrally -
welded attachments is 100% (170 for Unit I and 161 for Unit 2). Comed intends 'o
. submit, in the near future, a proposed new relief request which will incorporate the
- alternative selection criteria of Code Case N 509.
i; NRC Ouestion 3:
1
! What is the service histo:y of the bolted joints and integral attachments to which Relief
_ Request CR-23 will be applied?
L
! Comed Response to Ouestion 3:
l 2- BOLTED CONNECTIONS:
A service history review was performed on bolted connections in those systems which are -
- borated for the purpose of controlling reactivity. At Zion Station, these are the Reactor
[' Coolant. system, Safety Injection system, Residual Heat Removal system and Chemical and l : Volume Control system. The historical review focused on prior evidence ofleakage and in particular, recurring leakage. The results of the review, updated to reflect the lastest L information,' are shown below. Note that the service history of bolted connections applies
- to Relief Request CR-13 rather than CR-23.-
j - 1) REACTOR COOLANT SYSTEM Descriotion No.1 i
- Several years ago, asbestos gaskets in twelve (12) RTD manifold flanges per unit were replaced with non-asbestos gaskets.- The new gaskets leak from time to time such that
- j. at least one of the twelve is typically found with leakage every outage. l Page 3 of 5
- v ZRA97014 Enclosure-
' ' .The subject flanges have removable insulation and would be inspected with the insuletion removed in accordance with Relief Request CR 13, Rev.1.
- kanluliOD-It was determined that the gaskets being used were not the most effective for the-L 'specified applicatien, and that some flanges had alignment conditions that made it
- difficult to obtain a leak tight joint. Currently, when a leaking flange is identified, the
- gaskets is replaced with a new type that is better suited to the flange design. The L installation process includes measures to address potential flange mis-alignment.
Repairs made to Unit 1 RTD manifold flanges during the previous operating cycle appear to have been effective, since no leakage was identified at these flanges during walkdowns conducted at the start of the current outage in February of 1997. Repairs -
l made to Unit 2 RTD manifold flanges during the current outage will be re-tested as part ofunit re-start activities. Ifleakage does reoccur at RTD manifold flanges,
- Comed will explore additional measures to eliminate the leakage.
Description No. 2 l
- Leakage at reactor coolant system letdown isolation valve, LCV-RC460, in both units -
has been a recurring problem. The valves have removable insulation and would be
! inspected with the insulation removed in accordance with Relief Request CR-13, 7
Revision 1.
Barslution Thus far, gaskets have been replaced and the bolted connections have been re-torqued,-
and the leakage has not recurred. -Ifleakage does recur, Comed intends to take additional actions, such as installing different gaskets, resurfacing flanges, and using increased torque values.
. 2) RESIDUAL HEAT REMOVAL SYSTEM Descriotion
- There are two insulated RHR check valves in Unit 2 which have exhibited body-to-
. bonnet leakage. The insulation on the valves is removable.
haoluti.on-Leakage at the check valves was determined to be the result of under-torquing of the bolts.- The leakage has been corrected by increasing the bolt torque, and higher torque values were incorporated into the applicable procedure.
Page 4 of 5
4
( -
ZRA97014 Enclosure 1
- 3) SAFETYINJECTION SYSTEM Description There are two insulated SI check valves in Unit I and four insulated SI check valves in
- Unit 2 which have exhibited body to-bonnet leakage. The insulation on the valves is removable.
, Resolution Leakage at the check valves was determined to be the result of under-torquing of the i
bolts. The leakage has been corrected by increasing the bolt torque, and higher torque l values were incorporated into the applicable procedure.
- 4) CHEMICAL AN* 'OLUME CONTROL SYSTEM 4
No history of recurring leakage was identified for Chemical And Volume Control i
system bolted joints to which Relief Request CR-13 will be applied.
INTEGRALLY WELDED ATTACHMENTS The service history of the integral attachments to which Relief Request CR-23 will be applied is as follows:
For the ten specific integrally welded attachments listed Table 1, au were found to be free of recordable indications during magnetic particle testing conducted during
- the previous refueling outage.
i
- Regarding all integrally welded attachments, in the first two ISIintervals, indications have been found in four (4) integrally welded attachments in each unit.
In all cases, the indications were determined to be innocuous fabrication defects ,
with no sign of service growth.
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f Page 5 of 5 l l _. , _ _ _ - -
'. . ZRA97014 ATTACIIMENT 1 ZION STATION RELIEF REQUEST CR-13 REVISION 1
Zion Station 3rd Interval Inservice Inspection Plan RELIEF REQUEST NUMBER: CR 13 (Page 1 of 2)
COMPONENT IDENTIFICATION Code Classes: I and 2 l
Reference:
IWA-5242(a)
Examination Categories: B-P, C-H l
Item Numbers: B15.10, B15.11, B15.20, B15.21, B15.30, B15.31, B15.40, B15.41, B15.50, B15.51, B15.60, B15.61, 'B15.70, B15.71, C7.10, C7.20, C7.30, C7.40, C7.50, C7.60, C7.70, C7.80
Description:
Alternative Rules for Insulation Removal at Bolted Connections in Systems Borated for the Purpose of Controlling Reactivity
[QDE REOUIREMENT IWA-5242(a) states "For systems borated for the purpose of controlling reactivity, insulation shall bi removed from pressure retaining bolted connections for visual examination VT-2."
BASIS FOR RELIEF Reliefis requested on the basis that compliance with the Code requirement would result in hardship or unusual difliculty without a compensating increase in the level of quality and safety.
The systems which are borated for the purpose of controlling reactivity at Zion Station are the Reactor Coolant, Residual Heat Removal, Safety Injection and Chemical and Volume Control systems. These systems encompass a large portion of the overall ISI program. These systems physically cover a large expanse of the Containment. Many areas in which this piping and the associated bolted connections are located are difficult to access (scaffold and/or laddering is required) and many of these areas are such that significant radiation exposures would be encountered.
In addition, the removal and reinstallation ofinsulation with plant equipment in operation at system pressure and temperature increases the risk of personnel injury and presents a safety concern to plant personnel. Clearly, the personnel risk and radiation exposure is significant for the removal and reinstallation ofinsulation at these bolted connections during pressure testing activities.
In order to identify leaking bolted connections to be repaired during the outage, the preferred time to perform this inspection is in the beginning of the outage afler depressurization of the reactor coolant system. To perform these inspections at pressure would involve holding the reactor coolant system at operating pressure and temperature for an extended period of time to allow for scaffold construction, insulation removal and VT-2 visual examination. This is normally a relatively short time frame when the unit is transitioning to cold shutdown. Holding the unit at normal operating temperature and pressure for an extended period of time would result in a significant delay (approximately one week) in going to cold shutdown. l 7-29 Revision 1
", Zion Station 3rd Interval I inservice Inspection Plan i RELIEF REQUEST NUMBER: CR-13
, (Page 2 of 2)
BASIS FOR RELlEE (cont'd)
Performing this inspection at the end of the outage would be ineffective, since fmding leakage then would constitute bringing the unit back to cold shutdown to perform the repair and then beginning the start up process over again. Also, in order to reinsulate the reactor coolant system at the end of the outage, the unit would have to remain at hot standby while the insulation is reinstalled and the scaffolding is removed. Typically, the reinstallation ofinsulation and removal of scaffolding is performed prior to leaving cold shutdown.
A VT-2 visual examination with the system depressurized would still provide adequate detection ofleakage because boric acid residue can be easily detected with insulation removed at the bolted connection.
Based on the previously stated reasons, Zion Station requests relief from the inspection at operating pressure requirements detailed in IWA 5242(a). In lieu of these requirements, Zion l Station proposes the alternative examination scenario that follows.
PROPOSED ALTERNATIVE EXAMINATION A system pressure test and VT-2 visual examination shall be performed each refueling outage without removal ofinsulation, after a minimum 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> hold time, on systems borated for the purpose of controlling reactivity.
Each refueling outage, removable insulation shall be removed from bolted connections in systems borated for the purpose of controlling reactivity, and a VT-2 visual examination shall be performed on the connections prior to conducting any activities that could remove evidence of leakage that may have occurred during the previous operating cycle. During this VT-2 examination, the connections are not required to be pressurized. Any evidence ofleakage shall be evaluated in accordance with IWA-5250 (as modified by approved Relief Request CR-14).
These alternatives will provide reasonable assurance that safety and integrity will be maintained for bolted connections in systems borated for the purpose of controlling reactivity.
7-30 Resision 1
0 ZRA97014 t
ATTACIIMENT 2 ZION STATION RELIEF REQUEST CR-23 REVISION 0 J
.., Zion Station 3rd Interval Insenice Inspection Plan R.ELIEF REQUEST NUMBER: CR 23 l (Page1of3) ;
l COMPONENT IDENTIFICATION Code Classes: 2
Reference:
IWC-2500-1 Examination Categories: C-C ltem Numbers: C3.10, C3.20, C3.30
Description:
Integrally Welded Attachments CODE REOUIREMENT Surface examinations shall be performed on welded piping attachments of those components that are required to be examined under Examination Category C.F, C-G, and C-H. Extent of l Examination is 100% of required areas of each welded attachment.
BASIS FOR REIJEF '
Reliefis requested on the basis that compliance with the Code requirement in some cases is impractical.
Examination of 100% of the weld length for the welded attachments, in some cases, is not possible due to attachment geometry. Comed estimates that in the total population of Code Item No. C3.10, C3.20, and C3.30 integrally welded attachments, approximately 25% (43 of 170 in Unit 1,40 of 161 in Unit 2), have some form ofinspection limitation due to configuration constraints. These limitations typically vary. Based on previous inspections, Comed estimates that as much as 62% of the weld may not be accessible for surface examination.
Ten (10) integrally welded attachments inspected during the Third ISI Interval in Unit I were found to have limited accessibility. A list of these attachments is provided in Table CR-23.1, along with the amount ofinspection coverage achieved for each attachment, In all cases, the limitations were physical interferences due to the configuration of the integrally welded attachments or associated support. Typical configurations resulting in inspection limitations are shoven in Figure CR-23.1.
Because these welds are not full penetration welds, performance of the alternative VT-1 visual examination on the inaccessible weld areas will provide satisfactory identification of defect development.
Based on this information, reasonable assurance of the continued stmetural integrity of the subject welds is achieved by performing the code required surface examination on accessible weld areas and VT-1 visual examination on the inaccessible weld areas.
7-49 Revision 0 j
,., Zion Station 3rd Interval Inservico Inspection Plan RELIEF REQUEST NUMBER: CR-23 (Page 2 of 3)
TABLE CR-23,1 LIMITED COVERAGE EXAMINATIONS ON UNIT 1 INTEGRALLY WELDED ATTACHMENTS ATTACHMENT / SUPPORT SURFACE EXAMINATION NUMBER COVERAGE ACHIEVED CWE-2-2100-ISiO5W 66 %
CWE 2-2100-IS110W 48 %
CWE-2 2100-2Sil7W 60%
CWE-2-210lSiO2W 90 %
CWE-2-2200-1/H05W 93 %
CWE-2-2200-laiO6W 59%
CWE-2-2200-l/H07W 59%
CWE-2-2200-1/H08W 38%
CWE-2-2200-2/H14W 87 %
CWE-2-2200-2/H15W 60 %
PROPOSED ALTERNATE EXAMINATION For those supports with inspection hmitations listed in Table CR-23,1, surface examinations will I be performed on the accessible areas and a VT-1 visual examination will be performed on the remaining areas. The limitation will be documented on the surface examination data sheet and the percentage will be recorded in addition to the actual measured weld length for the accessible areas. The limitation will be documented in the ISI summary report and the NIS-1 report.
For future inspections, integrally welded attachments with limited accessibility will be subject to the criteria stated above. Ai! suspected limitations will be identified prior to the inspections and will be verified during the inspections. The verified limitations will then be identified in the ISI Program and will be categorized separately for future inspections.
7-50 Revision 0
.,* Zion Station 3rd Interval l Inservice Insp:ction Plan ;
\
- RELIEF REQUEST NUMBER: CR-23 (Page 3 of 3)
FIGURE CR-23.1
'ITPICAL ACCESS LIMITATIONS FOR INTEGRALLY WELDED ATTACHMENTS AD0lil0NAL PLATES WELDED IN THESE AREAS ADDITIONAL PLATES WELDED IN ,,
,'N THESE AREAS REOUCE ACCESS .
FOR SURFACE EXAM /
_ ) jf DIAMETER FEEDWATER PIPING t ,
& Q: -
A DETAll A- A M-
- + ,-
CWE-2-2101/H02W B
3 THE WELDS FOR THESE TWO SUPPORTS OVERLAP. THE DISTANCE BETWEEN THE 34 0A. TWO SUPPORT MEMBERS IS ONLY 1 1/2',
yy STEAM
- l. ___. . M B- *
- . -*- . -p .
DETNL B-B NO EXAM IN THESE AREAS DUE TO CONFIGURATION CWE-2-2100-2/H17W 4-THE DISTANCE BETWEEN TOP VIEW THE PIPE AND THE WELD 4 INNER ATTACHMENT IS ONLY 31/2", 34. DIA-MAIN WELDS -- - B" 0F WELD THIS IS NOT ADEQUATE SPACE LENGTH NOI I STEAM 12 EXAMINED ON
- TO PERFORM A SURFACE i EXAMINATION ON THE ENTIRE -~
LENGTH OF THE INNER WELDS.
{
31/2*E C
+ DETAIL C-C CWE-2-2200-1/H06W 7-51 Revision 0
. ZRA97014 ATTACIIMENT 3 LIST OF COMMITMENTS IDENTIFIED IN TIIIS RAI RESPONSE
. i Attachment 3 to ZRA97014 Page1 of2 i List of Commitments Identified in this RAllt1R9P.R The following table identifies those actions committed to by Comed in this document, pending approval of the associated relief requests. Any other actions discussed is this submittal represent intended or planned actions by Comed, They are described for the NRC's information and are not regulatory commitments.
Please notify Mr. Robert Godley, Zion Station Regulatory Assurance Manager, of any questions regarding this document or any associated regulatory commitments.
Commitment Committed Date or
, Outage
- Removable and non-removable insulation will be defined as follows: Start Z2R15 4
Removable insulation is stainless steel reflective insulation with Quick i
release buckles. Non-removable insulation is Calcium Silicate or Fiber glass insulation banded in place and covered with an aluminum jacket that is secured by metal banding or sheet metal screws.
The ISI Program will be modified to implement Relief Request CR-13, Start Z2R15 Rev.1, which applies to the following:
Coda Classes: I and 2 Table: IWC-2500-1 Examination Categories: B-P, C-H Item Numbers: B15.10, B15.11, B15.20, B15.21, B15.30, B15.31, B15.40, B 15.41, B 15.50, B 15.51, B15.60, B15.61, Bl5.70, B15.71, C7.10, C7.20, C7.30, C7.40, C7.50, C7.60, C7.70, C7.80 Start Z2R15
, The ISI Program will be modified to implement Relief Request CR-13, Rev.1, which requires the following in lieu of the requirements ofIWA-5242(a):
A system pressure test and VT-2 visual examination shall be performed each refueling outage without removal ofinsulation, after a minimum 4
- hour hold time, on systems borated for the purpose of controlling reactivity.
Each refueling outage, removable insulation shall be removed from bolted connections in systems borated for the purpose of controlling reactivity, and a VT-2 visual examination shall be performed on the connections prior to conducting any activities that could remove evidence ofleakage that may have occurred during the previous operating cycle. . During this VT-2 examination, the connections are not required to be pressurized. Any evidence ofleakage shall be evaluated in accordance with IWA-5250 (as modified by approved Relief Request CR-14).
Attachment 3 to ZRA97014
+
Page 2 of 2 Commitment Committed Date or Outage End ZlRIS The ISI Program will be modified to implement Relief Request CR-23 which applies to the following:
Code Class: 2 Table: IWC-2500-1 Examination Categories: C-C ltem Numbers: C3.10, C3.20, C3.30 End Ziki5 The ISI Program will be modified to implement Relief Request CR-23 which requires the following in lieu of the Table IWC 2500-1 requirement that the Extent of Examination be 100% of required areas of each welded attachment.
i For those suppons with inspection limitations listed in Table CR-23.1 of
' Relief Request CR-23, surface examinations will be performed on the accessible areas and a VT-1 visual examination will be performed on the remaining areas. The limitation will be documented on the surface examination data sheet and the percentage will be recorded in addition to the actual measured weld length for the accessible areas. The limitation will be documented in the ISI summary report and the NIS-1 report.
For future inspections, integrally welded attachments with limited accessibility will be subject to the criteria stated above. All suspected limitations will be identified prior to the inspections and will be verified
' during the inspections. The verified limitations will then be identified in the ISI Program and will be categorized separately for future inspections.