W3F1-2007-0059, Response to Request for Additional Information on Request for Alternative W3-ISI-004 - Proposed Alternative to Second Interval ISI Examinations, Waterford Steam Electric Station, Unit 3

Response to Request for Additional Information on Request for Alternative W3-ISI-004 - Proposed Alternative to Second Interval ISI Examinations, Waterford Steam Electric Station, Unit 3

ML073461088
Person / Time
Site:	Waterford
Issue date:	12/11/2007
From:	Murillo R Entergy Nuclear South
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
W3-ISI-004, W3F1-2007-0059
Download: ML073461088 (18)

Text

Entergy Nuclear South Entergy Operations, Inc.

17265 River Road Killona, LA 70057-3093 Entergy Tel 504-739-6715 Fax 504-739-6698 rmurill@entergy.com Robert J. Murillo Licensing Manager Waterford 3 W3F1-2007-0059 December 11, 2007 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

Response to Request for Additional Information on Request for Alternative W3-ISI-004 - Proposed Alternative to Second Interval ISI Examinations Waterford Steam Electric Station, Unit 3 Docket No. 50-382

REFERENCES:

1 Entergy letter dated August 7, 2007, Request for Alternative W3-ISI-004 ProposedAlternative to Second Interval ISI Examinations(CNRO-2007-00027) 2 NRC letter dated November 30, 2007, Waterford Steam Electric Station, Unit 3 - Request for Additional Information on the Request for Alternative W3-1SI-004, ProposedAlternative to Second Interval Inservice Inspection Examinations

Dear Sir or Madam:

Per Reference 1, Entergy proposed an alternative to the inspection requirements of ASME Code, Section Xl IWA-2430(a) and IWB-2500(a) for seven (7) dissimilar metal welds found in the Reactor Coolant System cold leg piping at Waterford Steam Electric Station, Unit 3 (W-3).

In a telephone call held on November 19, 2007, Entergy discussed with the staff the draft Request for Additional Information (RAI) and agreed to provide a response to the RAI by December 11, 2007. On November 30, 2007, Entergy originally received the NRC letter requesting a response to the RAI. Our response to the RAI is contained in Attachment 1.

,A-OY7

W3F1-2007-0059 Page 2 of 3 This RAI response includes a revision to the commitment specified in Reference 1 and stated in . If you have any questions or require additional information, please contact Ron Williams at 504-739-6255.

Sincerely, RJM/RLW/

Attachments:

1. Response to Request for Additional Information (RAI) for Request for Alternative W3-ISI-004 - Proposed Alternative to Second Interval ISI Examinations

2. Weld Repair Records and Fabrication Details

3. List of Regulatory Commitments

W3F1-2007-0059 Page 3 of 3 cc: Mr. Elmo E. Collins, Jr.

Regional Administrator U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 NRC Senior Resident Inspector Waterford Steam Electric Station Unit 3 P.O. Box 822 Killona, LA 70066-0751 U. S. Nuclear Regulatory Commission Attn: Mr. N. Kalyanam Mail Stop O-07D1 Washington, DC 20555-0001 Wise, Carter, Child & Caraway ATTN: J. Smith P.O. Box 651 Jackson, MS 39205 Louisiana Department of Environmental Quality Office of Environmental Compliance Surveillance Division P. O. Box 4312 Baton Rouge, LA 70821-4312 American Nuclear Insurers Attn: Library Town Center Suite 300S 2 9 th S. Main Street West Hartford, CT 06107-2445

.5 Attachment 1 W3F1-2007-0059 Response to Request for Additional Information (RAI) for Request for Alternative W3-ISI-004 - Proposed Alternative to Second Interval ISI Examinations to W3F1 -2007-0059 Page 1 of 9 Waterford Steam Electric Station, Unit 3 Response to Request for Additional Information for Request for Alternative W3-1SI-004 - Proposed Alternative to Second Interval ISI Examinations Reference 1 - Entergy letter dated August 7, 2007, Request for Alternative W3-ISI-004 ProposedAlternative to Second Interval ISI Examinations (CNRO-2007-00027)

Reference 2 - NRC letter dated November 30, 2007, Waterford Steam Electric Station, Unit 3

- Request for Additional Information on the Request for Alternative W3-1S1-004, ProposedAlternative to Second Interval Inservice Inspection Examinations RAI I - MRP-109 utilizes a crack growth rate with a stress intensity threshold value of 9 MPa-m0 5. MRP-109 evaluations were limited to flaws with aspect ratios of 2:1 and 6:1. Largeraspect ratio flaws, up to 21:1 have been identified during examinations of other dissimilarmetal welds. The flaws assumed in MRP-109 totachieve a 1 gallon per minute (GPM) leak rate may not be indicative of a realisticflaw shape and therefore, may overly predict the time from a 1 GPM leak until failure of the weld. Therefore, alternate analyses other than MRP-109 are necessary to support the conclusions made in the proposed alternative W3-1S1-004. Please provide results from the advanced finite element analysis regardingpredicted flaw shapes and growth.

Entergy Response:

Reference:

Response from Westinghouse letter CW-TR3-07-254 dated 12/3/07 and authoredby Warren Bamford, team member on the expert panel for MRP-216, Rev 1 (spring 08 advance FEA).

The MRP-109 crack growth analysis was performed using the MRP-21 Crack Growth Rate (CGR) formula. MRP-21, issued in 2000, reported an effort to predict a Crack Growth Rate (CGR) for Alloy 182 weld metal. The MRP-21 formula used the crack growth rate model that was developed for Alloy 600 material, and increased it by a factor of five to account for the expectation that Alloy 182 might crack five times faster than Alloy 600. The MRP-21 formula includes an assumed threshold stress intensity factor below which cracks will not propagate by primary water stress corrosion cracking (PWSCC), which is expected because this formula is derived from the formula for Alloy 600, rather than from Alloy 182 test data.

MRP-1 15, issued in late 2004, reported an effort to predict a Crack Growth Rate (CGR) for Alloy 182, Alloy 132, and Alloy 82 weld metals. MRP-1 15 was a significantly more sophisticated effort than MRP-21, and developed a formula for CGR specific to weld metals based on fitting curves to available test and field data for the weld metals. No threshold could be defined from the available data, so it was not assumed. The crack growth rate curve was otherwise very similar to MRP-21.

Since the MRP-109 crack growth analysis was performed using the MRP-21 CGR formula, the results of MRP-109 had to be reconciled to the new knowledge documented in MRP-1 15. This was reconciled in MRP-1 13 and led to changes to the results of MRP-109. The CGR formula from MRP-1 15 results in higher (than MRP-21) crack growth for applied stress intensity factors below about 15 MPa'lm, and lower crack growth for applied stress intensity factors above about to W3F1-2007-0059 Page 2 of 9 15 MPa-/m. This resulted in a reduced time for a crack to grow from an initial flaw to a through wall flaw, and increased the time for a through wall flaw to grow to a critical flaw size. Since it would take longer for a through wall flaw to grow to a critical flaw size using the MRP-1 15 CGR formula, use of the MRP-109 reported times (which use the MRP-21 CGR formula) will not overly predict the time from a 1 GPM leak until failure of the weld due to the stress intensity threshold.

While it is true that larger aspect ratio indications have been identified, this is true only for circumferential orientations, since axial flaws can only grow to the end of the weld. Therefore, this discussion will concentrate on the circumferential orientation. In general, the advanced crack growth calculations showed significantly larger margins than those completed using standard techniques. For example, for the Wolf Creek Relief line, which had an initial indication depth of 26 percent of the wall thickness, and length of 43% of the circumference, the advanced analysis showed it took three times as long for the flaw to penetrate the pipe wall. Furthermore, the flaw broke through only locally, thus demonstrating leak before break.

For circumferential flaws, the advanced finite element analysis completed for the pressurizer nozzles showed that larger aspect ratio flaws grew around the pipe, and then eventually penetrated the wall locally. This behavior was due to the residual stress in the welds, and occurred for all the residual stress scenarios considered. Using the variable flaw shape, flaws typically took much longer to penetrate the wall compared to a constant shape flaw, and in many cases arrested before penetration, due to the residual stress distribution. When the flaw did penetrate the wall, it did so locally, thus promoting leakage before rupture. Since the flaws typically got longer before penetrating the wall locally, this behavior was not sensitive to the initial flaw shape.

The evaluation of the RC Pump (RCP) safe ends and the Safety Injection (SI) nozzle safe ends also demonstrated large margins. These safe-ends are at a temperature of TCood and thus have a very low probability of a PWSCC crack initiating and lower growth rate than that predicted for the pressurizer region.

The RCP safe ends are also a very large diameter, and therefore there is a very large margin between leak and break. As stated in the original submittal, and reproduced below, the critical flaw size determined in MRP-1 09 for these locations is very large, over 29% of the circumference and through wall, with a total critical length of at least 33 inches (see table below). A one gpm leak results from a through-wall flaw of just over 2 inches, so there is a very large margin between leak and break. Therefore, alternative analysis of this configuration is not needed to support the proposed alternative. Using the advanced analysis methodology (MRP-216) would be expected to show even greater margin, but MRP-216 was developed primarily to deal with smaller pipe sizes where the margins were not so large. Given the large margin available, addition analysis is not needed for the large diameter RCP nozzles.

to W3F1-2007-0059 Page 3 of 9 Weld WF3 ISI 1 GPM Leak Time for Thru-walI Critical Flaw Size2 Analyzed Weld No. Crack Size Crack' to Reach - Circumferential (MRP-109) Critical Flaw Sizeý Thru-wal] Length RCP 11-002 2.65 inches > 40 Years 36.5 inches Suction 13-016 (32% of Circ.)

RCP 12-012 2.24 inches > 40 Years 33.2 inches Discharge 14-002 (29% of Circ.)

Notes:

1. 'Thxough-wall crack' is defined as producing a 1 gpm leak.

2. "Critical flaw size" is the flaw size that would resulf in failure under a specified load calculated using fracture mechanics.

The margin will be somewhat less for the smaller diameter safety injection nozzles (12 inch diameter) using traditional analysis methodology. The Pressurizer surge nozzle model is the same diameter and thickness as the SI nozzle, so it was used to support the proposed alternative, because the SI nozzle safe ends were not specifically treated in MRP-109. The MRP-109 results showed that more than 18 months were required for a flaw in the governing CE-design surge line with a one GPM leak to reach a critical flaw size. Since the SI nozzles are similar in size, but operate at much lower temperatures and with lower loads, this result was judged to be conservative. A view of the level of conservatism can be obtained by considering the extensive advanced analysis runs made for the surge nozzle butt weld and documented in MRP-216.

The advanced analysis for the surge nozzle cases included a large range of loadings. These analyses are judged to be bounding because thermal stratification loads do not exist for the SI nozzles. The most relevant case in MRP-216 is case 18a, which is a surge nozzle with low bending loads, but typical residual stresses. The postulated flaw in this case was 360 degrees around, which conservatively envelopes all flaw shapes, and 10% of the pipe wall. For this case, the crack arrested before penetrating the wall, thus demonstrating that the structural integrity is not challenged. This conclusion would apply directly to the SI nozzles and supports the proposed alternative.

While the original proposed alternative was based on MRP-109 results, consideration of the more advanced work in MRP-216 shows that the original basis was conservative.

RAI 2 - As residual stress is as important as operating temperature for flaw initiation and growth, please addressthe estimated residual stress in the welds and how this level of stress affects susceptibility to primary water stress-corrosioncracking. Please provide weld fabricationdetails and any documented repairsmade to the nozzle welds and any other details which could affect the weld residual stress profile for those welds which examination deferral is requested.

to W3F1-2007-0059 Page 4 of 9 Entergy Response:

Reference:

Response from Westinghouse letter CWTR3-07-254 dated 1213/07 and authoredby Warren Bamford, team member on the expert panel for MRP-216, Rev I (spring 08 advance FEA).

Welding residual stresses were used in the evaluations documented in RAI 1 above, so their impact on the results was directly assessed. Local repairs do increase the residual stresses, but the effect is local, which promotes leak before break. Regardless of repairs, the primary driving factor for PWSCC is temperature, and the low temperature at these locations of interest plays a major part in our assurance that the proposed alternative is appropriate. There have been no leaks in the industry on large bore cold leg temperature butt welds.

MRP-109 did consider residual stress in the crack growth analysis, but they used generic recommendations from the ASME Section XI flaw evaluation paper published in the Journal of Pressure Vessel Technology, Vol. 108, dated August 1986. The MRP-109 residual stress profiles did not assume any weld repairs - the ASME recommendation values used a maximum of 30,000 psi residual stress for both axial and circumferential directions. This is detailed in section 4.2 of MRP-109.

MRP-109 left some unanswered questions regarding residual stress profiles, and the effects of weld repairs. To address these questions, MRP-106 determined residual stress profiles using FEA models (Dominion Engineering). The results of MRP-106 were bounded by the MRP-109 analysis except for welds that had been repaired from the inside diameter (ID).

MRP-106 performed analysis that determined the residual stress distributions in as-designed butt welds and in butt welds that had been repaired from the inside surface. The results showed that the stress distribution for as-designed butt welds with no repairs results in relatively low stresses at the inside surface, and would be expected to sustain axial cracking over circumferential cracking. Welds that had repairs from the inside surface result in higher residual stresses at the inside surface, and the direction of stress would equally support axial or circumferential crack orientation.

With the weld repair residual stress information from MRP-106, the question of how a weld repair would affect the results of MRP-1 09 remained. To evaluate this, MRP-1 14 was issued.

MRP-1 14, section 3.2, defined the weld repairs assumed for the analysis. MRP-1 14 only evaluated reactor vessel outlet nozzle and pressurizer surge nozzle piping welds, but both of these geometries are similar to those of interest here.

MRP-1 14 evaluated the effect of weld repairs on dissimilar metal (DM) butt welds. This report documents that, for weld repairs made from the outside of the pipe, the resulting weld contains beneficial weld residual stress with respect to crack growth, similar to that for the as-welded condition. For this reason, effects of weld repairs performed from the outside of the pipe have no significant effect on the conclusions reported in MRP-109. However, repairs that are performed from the inside surface of the pipe result in significantly higher axial and circumferential residual tensile stresses in the repair area. These higher residual stresses in the repair area can create conditions that lead to shorter cracking times than would be expected for un-repaired welds (MRP-1 09). Two different ID weld repair configurations could be expected.

One is a relatively shallow repair that extends for the full 360 degree circumference of the pipe, to W3F1-2007-0059 Page 5 of 9 and the other is a relatively deep repair over a limited distance. In this report, the circumferential length of the weld repairs analyzed were equivalent to 30, 60, 90, and 360 degrees of the pipe circumference. The weld residual stress decreases rapidly with distance from the weld repair (both circumferentially and axially).

It is unlikely that a flaw will initiate and grow uniformly for the entire 360 degree circumference.

This is due to the non-uniform nature of residual and applied stress, and that there is no initiation mechanism identified in the PWR fleet similar to the condition that existed at the Duane Arnold recirculation inlet nozzles (BWR). Because of these factors, it is unlikely that a flaw will initiate for the full 360 degrees around the pipe at the ID surface of the weld, and any flaw that does initiate is not expected to grow uniformly for the full 360 degrees around the pipe. This would result in cracks that would produce leaks consistent with the analysis documented in MRP-109. The advanced analysis further supports this conclusion.

Regarding those welds that experience a relatively deep repair over a limited distance, the initiated flaws would tend to grow through-wall within the weld repair region, and, except for very high piping load cases, would grow through the wall beyond the weld repair for only short distances. Because of this tendency for the flaw to grow through wall in the localized area of the repair, and due to the fact that the weld residual stress decreases rapidly with distance from the weld repair, the results of MRP-109 remain valid for evaluating the safety significance of this Relief Request.

In summary, the residual stresses used in the assessments which form the basis of the proposed alternative bracket those which are expected in the locations of interest. Even with consideration of any potential repairs in the regions of interest, and the residual stresses which may have resulted, the conclusion remains that the integrity of the welds of interest will be maintained, and that the proposed alternative is a reasonable approach.

The weld repair records and fabrication details for these regions have been examined, and the results are tabulated in Attachment 2. A review of the repair records was performed and does not alter Entergy's basis for the proposed alternative.

RAI 3 - Can any of the welds be made to achieve at least a 90 percent American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code), Appendix VIII ultrasonicexamination coverage through grinding or machining the weld surface to change the profile and allow for satisfactory ultrasonictransducercontact with the surface?

Entergy Response:

The welds in question have a cast stainless steel safe-end that limits the examination to one side and the outside diameter (OD) configuration will not allow good ultrasonic coupling.

Grinding/machining will improve the OD configuration, but since the cast stainless steel safe-end on one side of the weld precludes examination from that side, grinding/machining will not assist in achieving at least 90% qualified Code coverage.

to W3F1-2007-0059 Page 6 of 9 RAI 4 - Have any of the other reactorcoolant pump suction or discharge or safety injection tie to reactorcoolant loop dissimilarmetal welds been examined using ASME Code, Section X1, Appendix VIII methods? If so, what percentageof coverage was obtained and what were the results?

Entergy Response:

None of the DM welds were examined to ASME Code Section Xl Appendix VIII methods. The welds were examined to the requirements of ASME Code Section Xl pre-Appendix VIII requirements. There were no reported unacceptable indications.

RAI 5 - How much radiologicaldose is estimated to install the seven weld overlays during 15th refueling outage (RF15)? How many additional welders and nondestructive examinationpersonnel would be requiredto maintain personnel dose to within site as-low-as-reasonablyachievable (ALARA) limits? What are the site ALARA limits?

Entergy Response:

To install these seven (7) cold leg DM weld overlays of interest during RF15, the radiological dose is estimated to be 20 REM. This total radiological dose is in addition to the 15 REM estimated to install the nine (9) pressurizer and hot leg DM weld overlays currently scheduled during RF15.

Currently, W3 has scheduled seven welding crews with approximately forty-two (42) vendor craft personnel per 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shift operating up to seven welding machines simultaneously to support installation of weld overlays on nine (9) pressurizer and hot leg nozzles. To install the additional seven nozzle weld overlays, Entergy and the vendor would essentially use the same experienced craft to install the additional seven large bore cold leg weld overlays during RF1 5 to the maximum extent permitted by dose to the welders and NDE technicians. Additional craft personnel would be necessary due to (1) four of the seven welds are 30" diameter RCP nozzles that are over twice the size previously experienced by vendors in PWR overlay work; and (2)

W3 is at least the fourth plant that will be serviced by the vendor in the spring. This would require some exchange of welders who have commitments for similar work later in the year.

The site ALARA administrative dose limit is 2 REM per year per individual.

RAI 6 - Have vendors been contacted to determine the welding resources available for application of the seven additionalweld overlays during RF15? What vendors were contacted and what welding resources are available?

Entergy Response:

Waterford 3 has contacted our welding vendor, Welding Services Inc. (WSI), and Westinghouse regarding their ability to install weld overlays on the seven (7) cold leg nozzles during RF-15.

With four (4) of these seven (7) cold leg nozzle being 30 " diameter RCP suction and discharge nozzles, the installation of DM weld overlays on this size pipe nozzle would be a first time to W3F1-2007-0059 Page 7 of 9 evolution for our vendor on a PWR. Entergy is not aware of a PWR that has had a weld overlay applied on this size nozzle near cast stainless steel.

WSI resources are currently scheduled to install DM weld overlays on nine (9) Alloy 600 butt welds in the reactor coolant system for the pressurizer and hot leg during RF-1 5. This is the largest number of overlays performed by WSI at one time on this type of nozzle. It is Entergy's understanding that the present demand for qualified nuclear welders and NDE technicians involved in overlay work in the spring of 2008 is extremely challenging to all nuclear vendors in the industry that perform this service.

RAI 7 - How much time would it take to engineer the seven weld overlays? How much time would it take a vendor to develop mock-ups and qualify procedures,equipment, and personnel? Pleaseprovide the basis for the estimates.

Entergy Response:

It is estimated that it would take four (4) months to complete the engineering work on the seven (7) weld overlays discussed in this Request for Alternative. As part of the engineering work, the sizing calculations, design drawings, limited mock-up and NDE are being planned as contingency for the seven (7) cold leg nozzles and are part of the Waterford 3 RF1 5 emergent scope. However, the four months are required to complete mock-ups, equipment fabrication, integrated testing demonstration and personnel qualifications that were not included in the RF15 scope. The four month duration is based on current planning experience with the nine (9) pressurizer and hot leg nozzle weld overlays, ranging in size from 2" to 14", that are scheduled for installation during RF15.

If this Request for Alternative is not approved and overlay work becomes necessary, then the complete scope of engineering work remaining for the seven (7) welds would need to be accomplished on an emergent basis. The schedule to complete the mock-ups, equipment fabrication, integrated testing demonstration and personnel qualifications would be accelerated to the maximum practical, assuming engineering resources could be made available at both the vendor and utility.

Similar equipment, processes and procedures for the currently planned outage overlay scope (9 welds) would be used as applicable and applied to the added scope. Although the components would be the same, the design of the larger welding machines would be a first time evolution and entail accepting risk during their production.

Currently, RF15 overlay design and analysis is in progress at Structural Integrity for each of the nine (9) welds. In parallel, NDE instruments are being developed and welding machines &

mock-ups are in fabrication at the WSI site. There are approximately fifty-five (55) documents consisting of drawings, calculations, weld travelers, procedures, etc, being prepared for the currently scheduled nine (9) RF1 5 weld overlays. This is an eight month effort that was beg-On in early August 2007 and scheduled for completion by early April 2008 to support a April 27, 2008 RF1 5 commencement. As noted above, some of this work is in-progress for the seven (7) additional weld overlays on the four (4) 30" RCP nozzles and three (3) Safety injection nozzles.

This includes only the sizing calculations and drawings. If the seven welds are included in the outage scope approximately 30 additional documents would be required. When completed these documents require review and comment resolution prior to commencement of integrated mock-up testing and craft training.

to W3F1-2007-0059 Page 8 of 9 RAI 8 - What are,the thicknesses of seven welds, and what is the range of overlay thicknesses qualified under the PerformanceDemonstration Initiative procedures?

Entergy Response:

A. The thicknesses of the seven (7) Dissimilar Metal Welds are as follows:

ISI Weld # Description Weld Thickness11-002 RCP-2A suction 3.53"12-012 RCP-2A discharge 3.20"13-016 RCP-2B suction -3.35"14-002 RCP-2B discharge -3.38"10-008 SI Loop 1B -1.49"12-009 SI Loop 2A 1.40"14-006 SI Loop 2B 1.35" B. The range of overlay thicknesses qualified under the Performance Demonstration Initiative Program (PDI) procedures, specifically under PDI-UT-8 Rev. 0, Addenda 0, span the following thickness and diameters. These ranges are the maximum ranges after applying field tolerances as allowed by Section Xl, Appendix VIII.

Present Capabilitv - Overlay Dimensions

" Minimum Diameter= 1.8"

• Maximum Diameter = unlimited

• Minimum Thickness = 0.05"

• Maximum Thickness = 1.35" Current PDI procedures are only qualified for examination of the upper 25% of the original weld and base material. Current PDI procedures are not qualified for the examination of the cast base material.

RAI 9 - What duration outage extension is estimated to permit installationof preemptive structural weld overlays on the seven welds? Please provide the basis for the estimates.

Entergy Response:

Waterford 3 estimates that to perform the weld overlays on an additional seven (7) cold leg nozzles will add approximately thirty (30) additional days to the current refueling outage duration of twenty-five (25) days.

to W3F1-2007-0059 Page 9 of 9 The estimated outage extension is based on the currently planned installation of nine (9) DM weld overlays on the pressurizer and hot leg nozzles. These nozzles range in size from 2" to 14". The nine (9) nozzle weld overlay work scheduled for RF15 will take approximately sixteen (16) days. The estimated duration is the time following scaffold installation through NDE. This duration includes equipment set up, calibration, testing as well as the welding, machining and NDE. This duration does not include scaffolding erection, insulation and whip restraint/hanger removal, instrument and electrical determinations of the Pressurizer heater cables and instrument tubing, reactor coolant system resistance temperature detectors (RTD), and the associated restoration work.

Seven welding crews with approximately forty-two (42) WSI craft per 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shift (total craft 84), will have up to seven welding machines running simultaneously. Total dedicated vendor and Entergy support is estimated at approximately one hundred (100) personnel. This team would be used to perform the overlay work on the currently scheduled nine (9) weld overlays followed by the additional seven (7) cold legs, if required.

Due to space limitations inside the RCS biological shields, the significant amount of welding activity on the RCS is concentrated in a small area. Thus, the additional seven (7) weld overlays, consisting of four (4) - 30" RCP nozzle welds and three (3) -12" safety injection nozzles, would need to be performed in series with the currently scheduled nine (9) weld overlay work and take an additional 30 outage days to complete.

RAI 10 - Please revise the commitment to submit a request for alternative and commit to either examine the welds with an ultrasonicmethod acceptable to the NRC or to install a structuralweld overlay on the welds during the Waterford 3 16th refueling outage.

Entergy Response:

Entergy is hereby changing the commitment contained in Reference 1 to submit a request for alternative and commit to either examine the welds with an ultrasonic method acceptable to the NRC or to install a structural weld overlay on the welds during the Waterford 3 16th refueling outage. The change in the commitment is contained in Attachment 3.

Attachment 2 W3FI-2007-0059 Weld Repair Records and Fabrication Details to W3F1-2007-0059 Page 1 of 2 Weld Repair Records and Fabrication Details

1. Original Construction Weld Repair Information Table 13 - Rejection Notice Summary (From Westinghouse Report LTR-PCAM-07-65 [3.6])

Note: All table regulartext is a duplicate of the Westinghouse report data; italicized text indicates supplemental information to Westinghouse report data.

[#] Indicates Reference Number. A distinction was made between weld repairsperformed on the butter or weld prep and the Alloy 82 butt weld as indicatedin the left column. The butt welds were performed after final stress relief, therefore subsequent weld repairs would generate a higher susceptibility to localized PWSCC than weld repairsto the butteror weld prep due to residualstress. The butter/weld prep repairsare included so that all weld repairs associatedwith the DM welds would be represented.

DM Weld Repair?

(Versus Butter/

Weld Prep WF3 Defect Repair) Weld ID RN Number Part Description Description Repair Description Notes14-006 Loop 28 upper CL Damaged weld Grind and PT the ground Par No 771-1301 NO Loop 2B 1629 prep on safety area. Weld repair, SI Nozzle piping assembly i nozzle, machine and PT.11-002 Machine to remove NORCP Loop 2A 2140 Unspecified CL Unacceptable PT indications; PT inspect. Part No. 731-102-3 safe-end buttering indications on safe Butter the safe-end and Alloy [3.3]

Rct s n g end buttering. 182. Machine Suction inspect.

Loop 2B lower cold Excessive RT 13-016 leg indications found in Repair-welded with Alloy Part No. 771-1403-4 YES Loop 2B 2299 suction elbow to weld seam 1407- 182; details not' Seam No. 1407-771-D RCP Suction safe-end 771-D. available. [3.3]

weld 11-002 Loop 2A lower CL Excessive RT Part No. 771-1403-3 YES . Loop 2A 2793 suction elbow to indications after Grind out indications and Seam No. 1407-771-C RCP Suction safe-end first cycle; multiple repair Alloy 182. [3.3]

weld circ. Locations.13-016 Loop 2B lower CL. Excessive RT Part No. 771-1403-4 YES Loop 2B 3046 Suction elbow toDeetrmod;wl safe-end indications; r efects removed, weld Seam No. 1407-771-D RCP Suction weld multiple locations. epairs effected. [3.3]

Provide additional length 13-016 Loop 2B lower CL.Overall safe-end viwedblup lengthvia weld buildup; PartNo. 771-1403-4 NO Loop 2B 3071 Suction elbow machine, inspect and [3.3]

RCP Suction safe-end than allowed by butter safe-end Alloy dwg. 182.14-006 RT after 2nd cycle Part No. 771-1301 YES Loop 2B 3886 Upper CL safety unacceptable; Repaired; details not Seam No. 1303-771 SI Nozzle injection nozzle residual slag recoverable. [3.2]

remains in weld.12-009 Excessive RT Grind out defects and PartNo. 771-901 YES Loop 2A 3900 Upper CL safety indications in PT. Weld repair Alloy Seam No. 903-771 SI Nozzle injection nozzle buttering after first 182. [3.4]

cycle.

Note: All available original construction rejection notices were reviewed for applicability to the seven subject welds. This table contains information on relative weld repairs to the subject dissimilar metal welds or butter. The first column distinguishes whether a weld repair was performed on the Alloy 82 butt weld. The information contained in Table 13 is derived from all available data at Westinghouse and is a 'best effort' presentation of applicable weld repairs.

to W3F1-2007-0059 Page 2 of 2

2. Fabrication Details The root pass design shown in Figure 1 is typical of all seven locations. A weld prep was machined onto the mating surfaces on both components and the Alloy 82 butt weld was performed with a subsequent ID back-groove-and-fill. The design drawing for the Loop 2A RCP discharge DM weld and the Loops 2A and 2B RCP suction DM welds depict butter on the cast stainless steel safe end (Figure 1, weld ID's11-002, 12-012, and 13-016).

The design drawing for the Loop 2B RCP discharge DM weld and the Loops 1 B, 2A, and 2B safety injection nozzle DM welds do not depict butter on the cast stainless steel safe end (Figure 2, weld ID's14-002, 10-008,12-009, and 14-006). References [3.2], [3.3],

[3.4], [3.5]

Figure 1 (Applies to Loop 2A RCP discharge DM weld and the Loops 2A and 2B RCP suction DM welds)

Figure 2 (Applies to Loop 2B RCP discharge DM weld and the Loops 1B, 2A, and 2B safety injection nozzle DM welds)

3. References 3.1 Drawing 1564-930 (Vendor drawing 74470-771-012), "Primary Pipe Assembly" 3.2 Drawing 1564-931 (Vendor drawing 74470-771-013), "Primary Pipe Assembly" 3.3 Drawing 1564-932 (Vendor drawing 74470-771-014), "Primary Pipe Assembly" 3.4 Drawing 1564-918 (Vendor drawing 74470-771-009), "Primary Pipe Assembly" 3.5 Drawing 1564-929 (Vendor drawing 74470-771-011), "Primary Pipe Assembly" 3.6 Westinghouse Report LTR-PCAM-07-65, "PWROG PA-MSC-0233 Task 2 Deliverable Waterford Unit 3" 3.7 Vendor drawing 74470-771-001, "General Arrangement Waterford III Piping"

Attachment 3 W3FI-2007-0059 List of Regulatory Commitments

Attachment 3 to W3F1-2007-0059 Page 1 of 1 List of Regulatory Commitments The following table identifies those actions committed to by Entergy in this document. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.

TYPE (Check one)

COMMITMENT SCHEDULED ONE- CONT COMPLETION TIME COMP DATE (If ACTION Required)

Entergy will submit for NRC Staff approval a request for X October 30, alternativethat will commit to either examine the welds with 2008 an ultrasonicmethod acceptable to the NRC or to install a structuralweld overlay on the deferred dissimilarmetal welds contained in Request for Alternative W3-1SI-004 during the Waterford 3 1 6 th refueling outage.