CNRO-2005-00048, Relaxation Request 5 to NRC First Revised Order EA-03-009 for the Control Element Drive Mechanism Nozzles

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Relaxation Request #5 to NRC First Revised Order EA-03-009 for the Control Element Drive Mechanism Nozzles
ML052560109
Person / Time
Site:  Entergy icon.png
Issue date: 09/09/2005
From: Burford F
Entergy Operations
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
CNRO-2005-00048, EA-03-009
Download: ML052560109 (29)
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Text

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Entergy Operations, Inc.

Entergy - 1340 Echelon Parkway Jackson. Mississippi 39213-8298 Tel 601-368-5758 F. G. Burford Actng Director Nuclear Safety & Licensing CNRO-2005-00048 September 9, 2005 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

ANO-2 Relaxation Request #5 to NRC First Revised Order EA-03-009 for the Control Element Drive Mechanism Nozzles Arkansas Nuclear One, Unit 2 Docket No. 50-368 License No. NPF-6

REFERENCES:

1. Entergy Operations, Inc. letter CNRO-2004-00018 to the NRC, dated March 11, 2004
2. NRC letter to Entergy Operations, Inc. (TAC No. MC2303), dated February 7, 2005
3. Entergy Operations, Inc. letter CNRO-2003-00033 to the NRC, dated August 27, 2003
4. Entergy Operations, Inc. letter CNRO-2003-00047 to the NRC, dated November 11, 2003

Dear Sir or Madam:

In Reference 1, Entergy Operations, Inc. (Entergy) requested relaxation from Section IV.C.(5)(b) of NRC First Revised Order EA-03-009 (the Order) for Arkansas Nuclear One, Unit 2 (ANO-2) via ANO-2 Relaxation Request #4. Specifically, the bottoms of the ANO-2 control element drive mechanism (CEDM) nozzles contain threads that cannot be effectively examined in accordance with the Order. In Reference 2, the NRC staff granted Relaxation Request #4 for one operating cycle, which ends with upcoming refueling outage 2R1 8.

The conditions that required Entergy to submit relaxation to the Order remain (i.e., CEDM nozzle configuration). Therefore, pursuant to Section IV.F of the Order, Entergy requests relaxation from Section IV.C.(5)(b) of the Order for ANO-2. As with Relaxation Request #4, this request (ANO-2 Relaxation Request #5) proposes an alternative based on the same stress and fracture mechanics analyses approved in Relaxation Request #4. ANO-2 Relaxation Request #5 is provided in Enclosure #1.

CNRO-2005-00048 Page 2 of 2 Relaxation Request #5 is supported by:

1. Engineering Report M-EP-2003-002, Rev. 1, Fracture Mechanics Analysis for the Assessment of the Potential for Primary Water Stress Corrosion Crack (PWSCC) Growth in the Uninspected Regions of the Control Element Drive Mechanism (CEDM) Nozzles at Arkansas Nuclear One Unit 2, and
2. Dominion Engineering, Inc. Letter L-4162-00-1, Material Properties and Modeling Methods Used in ANO Unit 2 Welding Residual Stress Analyses.

Entergy previously submitted these documents to the NRC staff via References 3 and 4 in support of a previous relaxation request.

Entergy requests approval of ANO-2 Relaxation Request #5 prior to September 10, 2006 in order to support RPV head nozzle inspections to be performed during the upcoming fall 2006 refueling outage (2R18).

This letter contains commitments as identified in Enclosure 2.

If you have any questions or require additional information, please contact Guy Davant at (601) 368-5756.

Sincerely, FGB/GHD/ghd

Enclosures:

1. ANO-2 Relaxation Request #5
2. Licensee-identified Commitments cc: Mr. W. A. Eaton (ECH)

Mr. J. S. Forbes (ANO)

Dr. Bruce S. Mallet U. S. Nuclear Regulatory Commission Regional Administrator, Region IV Attn: Mr. D. G. Holland U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 NRC Senior Resident Inspector Arkansas Nuclear One P. O. Box 310 London, AR 72847

z ENCLOSURE I CNRO-2005-00048 ARKANSAS NUCLEAR ONE, UNIT 2 RELAXATION REQUEST #5

ENTERGY OPERATIONS, INC.

ARKANSAS NUCLEAR ONE, UNIT 2 RELAXATION REQUEST #5 TO NRC FIRST REVISED ORDER EA 03-009 ASME COMPONENTS AFFECTED Arkansas Nuclear One, Unit 2 (ANO-2) has ninety (90) ASME Class 1 reactor pressure vessel (RPV) head penetration nozzles comprised of eighty-one (81) Control Element Drive Mechanism (CEDM) nozzles, eight (8) Incore Instrument (ICI) nozzles, and one (1) vent line nozzle. This request pertains to the CEDM nozzles only. See Figure 1 for penetration locations on the ANO-2 RPV head.

In accordance with Section IV.A of NRC First Revised Order EA-03-009, the ANO-2 susceptibility category is "high" based on a calculated value of greater than 12 effective degradation years (EDY) at the beginning of the upcoming fall 2006 refueling outage (2R18).

II. NRC ORDER EA 03-009 APPLICABLE EXAMINATION REQUIREMENTS The NRC issued First Revised Order EA-03-009 (the Order) that modified the current licenses at nuclear facilities utilizing pressurized water reactors (PWRs), which includes ANO-2. The Order establishes inspection requirements for RPV head penetration nozzles. ANO-2 is categorized as a "high" susceptibility plant based on an EDY value greater than 12.

Section IV.C of the Order states in part:

All Licensees shall perform inspections of the RPV head using the following frequencies and techniques:

(1) For those plants in the High category, RPV head and head penetration nozzle inspections shall be performed using the techniques of paragraph IV.C.(5)(a) and paragraph IV.C.(5)(b) every refueling outage.

Section IV.C.(5) of the Order states in part:

(5) Inspections of the RPV head shall be performed as directed in paragraphs IV.C.(1), IV.C.(2), IV.C.(3), and IV.C.(4) using the following techniques:

(a) Bare metal visual examination of 100% of the RPV head surface (including 3600 around each RPV head penetration nozzle).

(b) For each penetration, perform a nonvisual NDE in accordance with either (i),

(ii), or (iii):

(i) Ultrasonic testing of the RPV head penetration nozzle (i.e., nozzle base material) from 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 2 inches below the lowest point at the toe of the J-groove weld on a horizontal plane perpendicular to the nozzle axis (or the bottom of the Page 1 of 24

nozzle if less than 2 inches); OR from 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 1.0 inch below the lowest point at the toe of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) and including all RPV head penetration nozzle surfaces below the J-groove weld that have an operating stress level (including all residual and normal operating stresses) of 20 ksi tension and greater. In addition, an assessment shall be made to determine if leakage has occurred into the annulus between the RPV head penetration nozzle and the RPV head low-alloy steel.

(ii) Eddy current testing or dye penetrant testing of the entire wetted surface of the J-groove weld and the wetted surface of the RPV head penetration nozzle base material from least 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 2 inches below the lowest point at the toe of the J-groove weld on a horizontal plane perpendicular to the nozzle axis (or the bottom of the nozzle if less than 2 inches); OR from 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 1.0 inch below the lowest point at the toe of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) and including all RPV head penetration nozzle surfaces below the J-groove weld that have an operating stress level (including all residual and normal operating stresses) of 20 ksi tension and greater.

(iii) A combination of (i) and (ii) to cover equivalent volumes, surfaces, and leak paths of the RPV head penetration nozzle base material and J-groove weld as described in (i) and (ii). Substitution of a portion of a volumetric exam on a nozzle with a surface examination may be performed with the following requirements:

1. On nozzle material below the J-groove weld, both the outside diameter and inside diameter surfaces of the nozzle must be examined.
2. On nozzle material above the J-groove weld, surface examination of the inside diameter surface of the nozzle is permitted provided a surface examination of the J-groove weld is also performed.

Ill. REASON FOR REQUEST Section IV.F of the Order states in part:

Licensees proposing to deviate from the requirements of this Order shall seek relaxation of this Order pursuant to the procedure specified below. Project Directors or higher management positions in the Division of Licensing Project Management of the Office of Nuclear Reactor Regulation, may, in writing, relax or rescind any of the above conditions upon demonstration by the Licensee of good cause. A request for relaxation regarding inspection of specific nozzles shall also address the following criteria:

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(1) The proposed alternative(s) for inspection of specific nozzles will provide an acceptable level of quality and safety, or (2) Compliance with this Order for specific nozzles would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

Requests for relaxation associated with specific penetration nozzles will be evaluated by the NRC staff using its procedure for evaluating proposed alternatives to the ASME Code in accordance with 10 CFR 50.55a(a)(3).

Pursuant to Section IV.F(2) of the Order, Entergy Operations, Inc. (Entergy) requests relaxation from the requirements of Section IV.C.(5)(b) for the remainder of the current (3rd) 10-year inservice inspection interval at ANO-2. Entergy plans to inspect RPV head CEDM penetration nozzles at ANO-2 using the ultrasonic testing (UT) method in accordance with Section IV.C.(5)(b)(i) of the Order to the maximum extent possible.

However, a UT inspection from the inside diameter (ID) of the CEDM nozzles at ANO-2 can only be performed from 2 inches above the root of the J-groove weld down to a point approximately 1.544 inches above the bottom of the nozzle. This 1.544-inch 'blind zone" is due to limitations resulting from CEDM nozzle configuration (1.344 inches) and inspection probe design (0.200 inch). These limitations and their associated hardships are discussed in Sections III.A and III.B.

Entergy also evaluated the impact of inspecting the blind zone of each CEDM nozzle using either the liquid penetrant testing (PT) method or the eddy current testing (ECT) method as specified in Section IV.C.(5)(b)(ii) of the Order. Entergy found impracticality and hardship with these techniques, as discussed in Section III.C.

A. Nozzle Configuration Limitation

1. Description Guide cones are attached to the bottoms of the ANO-2 CEDM nozzles via threaded connections. Specifically, the guide cone screws into the end of the CEDM nozzle with a welded set screw and two tack welds at the cone-nozzle interface to secure the guide cone to the nozzle. The length of the threaded connection region is 1.25 inches. Additionally, a 450 chamfer exists immediately above the threaded connection region. The length of the chamfer region is 0.094 inch. (See Figure 2 for typical nozzle details.)

Due to the threaded connection and chamfer region at the bottom of each CEDM nozzle, a meaningful UT examination in that area cannot be performed.

Specifically, the chamfer region geometry causes sporadic signals while, once the guide cone is reached, sound cannot pass into the CEDM nozzle base material because of the gap that exists between the guide cone and the nozzle at the threaded connection. Therefore, UT of the bottom 1.344 inches (1.25 + 0.094) of the CEDM nozzles is not possible.

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2. Hardship Resolving the UT limitations due to nozzle configuration would require eliminating the existing CEDM nozzle-to-guide cone threaded connection and chamfer region and redesigning and physically modifying the nozzle ends to provide for an acceptable UT examination. Entergy believes to take such an approach would impose hardships and unusual difficulties without a compensating increase in the level of quality and safety for the following reasons:

a) High Personnel Dose As mentioned above, a guide cone is attached to the bottom of each CEDM nozzle via'a threaded connection. Entergy has estimated that removing and reinstalling the 81 guide cones would result in personnel exposure of approximately 1.25 man-REM per nozzle for a total exposure of 101.25 man-REM.

b) Removing, Redesigning, and Reinstalling Guide Cones The guide cones would be removed by cutting them off at the top of the nozzle threaded region, which would result in a shorter nozzle below the J-groove weld.

The replacement guide cone is of a welded design that fits up to the end of the nozzle and is welded to the nozzle tube. To reinstall the cones would require a modification to the nozzle ends as well as fabrication of new cones. Having to remove the cones and replace them with new components results in additional modifications to the RPV head that go beyond the requirements and scope of the Order. In addition, installing the new guide cone would cause high residual stresses in the heat affected zone of the weld, which would increase the probability of primary water stress corrosion cracking (PWSCC).

c) Impact on Outaae Schedule Entergy estimates that to remove and reinstall each guide cone would require approximately eight (8) hours per nozzle adding as much as 27 days to the outage schedule.

B. Inspection Probe Design Limitation

1. Description The inspection probe to be used to inspect ANO-2 CEDM nozzles consists of seven (7) individual transducers, as shown in Figure 3. Various probe configurations will be utilized to perform the UT and ECT inspections [e.g., UT time-of-flight diffraction (TOFD) and standard 00 scans and low frequency ECT.]

The inspection probe is designed so that the ultrasonic transducers are slightly recessed into the probe holder. This recess must be filled with water to provide coupling between the transducer and the nozzle wall. Because of this design, Page 4 of 24

the complete diameter of the transducer must fully contact the inspection surface before ultrasonic information can be collected. Because UT probes 1 and 2 have a diameter of 0.250 inch, these transducers should, in theory, be able to collect meaningful UT data down to a point approximately 0.125 inch (1/2 diameter) above the chamfer. However, based on prior UT inspection experience and a review of UT data from previous inspections, the circumferential-shooting TOFD transducer pair only collects meaningful data down to a point 0.200 inch above the chamfer. Below this point, UT data cannot be collected.

2. Hardship Entergy knows of no UT equipment currently available that resolves the blind zone limitation; therefore, new UT equipment would have to be developed and appropriately qualified. The time and resources required to develop this equipment is unknown.

C. Impracticalitv and HardshiD of Performing Alternative Surface Examinations To perform a PT inspection, the guide cones would have to be removed from and reinstalled on the CEDM nozzles before and after performing the PT examinations.

Performing these operations would result in a significant increase in personnel radiation exposure. Entergy estimates that the radiation exposure associated with removing the guide cone, performing the PT inspection, and reinstalling the guide cone to be approximately 2.5 man-REM per nozzle for a total exposure of 202.5 man-REM. In addition, this option would also involve those hardships described in Sections IlI.A.2.a) and b), above.

As with the UT inspection, the bottom 1.344 inches (threaded connection and chamfer region) of the inside surface of the nozzle cannot be inspected using ECT.

In conclusion, CEDM nozzles can be volumetrically inspected in accordance with Section IV.C.(5)(b)(i) of the Order from 2 inches above the root of the J-groove weld to the top of the blind zone (approximately 1.544 inches above the bottom of the nozzle).

Below this point, Entergy believes that the hardships associated with inspection activities required by the Order as discussed above are not commensurate with the level of increased safety or reduction in probability of leakage that would be obtained by complying with the Order.

IV. PROPOSED ALTERNATIVE AND BASIS FOR USE A. Background CEDM nozzle inspections performed during the fall 2003 and spring 2005 refueling outages included the following components:

1. Entergy performed volumetric UT and inside diameter (ID) surface ECT from 2 inches above the J-groove weld to the lowest achievable extent below the weld, at a minimum. The UT included a 0° leakage path assessment and time-of-flight diffraction (TOFD) examination 0.060 inch into the J-groove weld-to-tube interface (including the triple-point area of the weld). No indications of PWSCC were identified.

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2. In cases where the inspection length below the J-groove weld required by the crack-growth analysis could not be achieved with the UT probe, Entergy performed manual ECT on the OD of the nozzle tube and J-groove weld to increase the inspection coverage. No indications of PWSCC were identified.
3. Entergy performed supplemental visual inspections from above the RPV cooling shroud. In addition, Entergy performed a bare metal visual examination on the RPV head flange and the portion of the RPV head extending out of the cooling shroud as well as 3600 around the in-core instrumentation (ICI) nozzles. Also, during the spring 2005 refueling outage, Entergy removed the cooling shroud and insulation, and performed a bare metal visual examination of the carbon steel surface of the reactor closure head, including 3600 around each penetration in accordance with Section IV.C.(5)(a) of the Order. No indications of penetration leakage, boric acid residue, or material wastage were identified.

Paragraph IV.C.(5)(b)(i) of the Order requires that the UT inspection of each RPV head penetration nozzle encompass from 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 2 inches below the lowest point at the toe of the J-groove weld on a horizontal plane perpendicular to the nozzle axis (or the bottom of the nozzle if less than 2 inches); OR from 2 inches above the highest point of the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 1.0 inch below the lowest point at the toe of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) and including all RPV head penetration nozzle surfaces below the J-groove weld that have an operating stress level (including all residual and normal operating stresses) of 20 ksi tension and greater. In addition, an assessment shall be made to determine if leakage has occurred into the annulus between the RPV head penetration nozzle and the RPV head low-alloy steel.

Due to the reasons stated in Section III, above, Entergy requests relaxation from this requirement for ANO-2 CEDM nozzles and proposes an alternative, which involves the use of UT examination, analysis, and augmented inspection techniques, as described below.

B. Proposed Alternative

1. UT Examination The ID of each CEDM nozzle (i.e., nozzle base material) shall be ultrasonically examined from two (2) inches above the root of the J-groove weld (on a horizontal plane perpendicular to the nozzle axis) to 1.544 inches above the bottom of the nozzle.

The data acquisition techniques used will be essentially the same as those used in previous examination activities.'

Refer to Entergy letters 2CAN120302, 60-Day Report forANO-2 ReactorPressure Vessel Head Inspection for Refueling Outage 2R16, dated December 8, 2003 and 2CAN060503, 60-Day Report for ANO-2 ReactorPressure Vessel Head Inspection forRefueling Outage 2R17, dated June 7, 2005 for more information.

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In addition, an assessment to determine if leakage has occurred into the interference fit zone will be performed, as currently specified in Section IV.C.(5)(b)(i) of the Order.

2. Analysis For the blind zone portions of the CEDM nozzle not examined by UT as required by the Order, analysis has been performed to:

a) Determine if sufficient free-span exists between the blind zone and the weld to facilitate one (1) operating cycle of crack growth without the crack reaching the weld, and b) For nozzles or portions of nozzles not meeting item 2.a), above, determine how much propagation length is required to facilitate one cycle of crack growth without the crack reaching the weld. This length is composed of the distance between the weld and the blind zone plus some additional distance into the blind zone. The additional distance into the blind zone area is defined in Table 1 and is subject to augmented inspection as described in item 3 below. This area to be inspected may include a portion of the weld.

The analysis is discussed in further detail in Section IV.C.2 below. The analysis methodology is fully documented in Engineering Report M-EP-2003-002, Rev.

1,which was previously submitted to the NRC. 2

3. Augmented Inspections CEDM nozzles that have been demonstrated by analysis to have inadequate free-span to ensure a crack will not grow to the J-groove weld within one operating cycle will be inspected. These nozzles and their associated augmented inspection areas are identified in Table 2. Specifically, an augmented inspection of the outside diameter (OD) will be performed on that portion of the nozzle that has been determined by analysis as necessary to prevent a crack from reaching the J-groove weld in less than one operating cycle. The augmented inspection will utilize either ECT or PT, or a combination of both techniques.

As required by Section IV.E of the Order, the final results of the inspections will be provided in the 60-day report submitted to the NRC.

C. Basis for Use The UT examination is the volumetric technique recognized in Section IV.C.(5)(b)(i) of the Order. The Entergy proposed alternative includes the use of UT to the maximum extent practical based on the limits of current technology. However, because the technology cannot provide an inspection to the extent required by the Order (i.e., to the bottom of the nozzle), Entergy proposes supplemental analysis 2 Entergy submitted Engineering Report M-EP-2003-002, Rev. 1 and associated changes to the NRC via Entergy letters CNRO-2003-00033 dated August 27, 2003 and CNRO-2003-00047 dated September 25, 2003.

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and augmented inspection. This approach provides a level of safety and quality commensurate with the intent of the Order. Each portion of the proposed alternative is discussed below.

1. UT Examination Entergy will perform UT inspection of the ANO-2 CEDM nozzles using a combination of TOFD and standard 0° pulse-echo techniques. The TOFD approach utilizes two pairs of 0.250-inch diameter, 550 refracted-longitudinal wave transducers aimed at each other. One of the transducers sends sound into the inspection volume while the other receives the reflected and diffracted signals as they interact with the material. There will be one TOFD pair looking in the axial direction of the penetration nozzle tube and one TOFD pair looking in the circumferential direction of the tube. The TOFD technique is primarily used to detect and characterize planar-type defects within the full volume of the tube.

The standard 00 pulse-echo ultrasonic approach utilizes one 0.250-inch diameter straight beam transducers. The 0° technique is used to:

  • Plot the penetration nozzle OD location and J-groove weld location,
  • Locate and size any laminar-type defects that may be encountered, and
  • Monitor the back-wall signal response to detect indications that leakage may have occurred in the interference regions of the RPV head penetration.

The UT inspection procedures and techniques to be utilized at ANO-2 have been satisfactorily demonstrated under the EPRI Materials Reliability Program (MRP) Inspection Demonstration Program.

2. Analysis The extent of the proposed alternative is established by an engineering evaluation that includes a finite element stress analysis and fracture mechanics evaluations. The intent of the engineering evaluation is to:

a) Determine whether sufficient crack propagation length is available between the tip of a postulated crack and the weld to facilitate one cycle of crack growth without the crack reaching the weld; b) Where sufficient available propagation length does not exist above the blind zone for a given nozzle, then determine how much additional length into the blind zone is required to provide one cycle of crack growth without compromising the weld. See Figure 4.

Four (4) CEDM nozzle locations were selected for analysis in the engineering evaluation. The selected locations (RPV head angles) were 00, 8.80, 28.80, and 49.60 with the 00 head angle at the vertical centerline of the RPV head, the 49.60 head angle location being the outermost nozzles, and the other two being intermediate locations between the center and outermost locations. The results of the stress analysis at each location yield a length that a postulated crack Page 8 of 24

would propagate during one refueling cycle (propagation length). For nozzle locations that are between the locations that were analyzed, the larger crack length calculated for the nozzle locations above or below was used to evaluate the adequacy of the available free span.

Based on these analyses, each nozzle was evaluated to determine whether the available propagation length is adequate to prevent crack propagation into the weld in less than one cycle of operation. For those nozzles that do not have adequate available propagation length, additional analysis was performed to define the nozzle area that is subject to an augmented inspection.

Stress Analysis A "finite element" based stress analysis was performed on the ANO-2 CEDM nozzles in this evaluation. For conservatism, the yield strength used in the analysis for each nozzle head angle location is the highest yield strength of all the nozzles at that head angle. To ensure that the finite element analysis (FEA) adequately models the as-built configuration of the selected ANO-2 CEDM nozzles and weld, a detailed review of design drawings and UT inspection data from the ANO-2 spring 2002 refueling outage was performed. Based on this review, the following was concluded:

  • CEDM Nozzles at 00 and 8.80 Head Angle Locations: Weld sizes at each nozzle location are similar to design. However, the as-built nozzle projections below the bottom of the RPV head are shorter than indicated by design. The FEA model was adjusted for this shorter nozzle projection.
  • CEDM Nozzles at 28.80 Head Angle Locations: The leg lengths of the welds on the downhill sides of the nozzles are longer than indicated by design.

The leg lengths of the fillet weld reinforcement on the uphill side of the nozzles match the design values. Nozzle projections below the bottom of the RPV head are in accordance with design. The FEA model was adjusted to account for the longer weld leg lengths on the downhill side of the nozzles.

  • CEDM Nozzles at 49.60 Head Angle Locations: The leg lengths of the welds on the downhill sides of the nozzles are longer than indicated by design and extend into the blind zone. The leg lengths of the welds on the uphill side of the nozzles match the design values. Nozzle projections below the bottom of the RPV head are in accordance with design. The FEA model was adjusted to account for the longer weld leg lengths on the downhill side of the nozzles.

The FEA determined the stress distribution from the bottom of the nozzle to just above the top of the weld at the downhill, uphill, and mid-plane azimuthal locations. The downhill and mid-plane locations were selected because they represent the shortest distances that a crack would have to propagate to reach the nozzle weld region. The uphill location was selected for completeness of the analysis. The stress distributions produced by this analysis were used to perform the fracture mechanics evaluations.

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Fracture Mechanics Evaluation Analyses performed by the MRP have demonstrated that axial cracks in the nozzle tube material do not pose a challenge to the structural integrity of the nozzle. However, axial cracks may lead to pressure boundary leaks above the weld that could produce OD circumferential cracks and structural integrity concerns. Therefore, proper analysis of potential axial cracks in the blind zone of the CEDM nozzle is essential.

Postulated cracks for the analysis include axial ID and OD part through-wall and through-wall cracks. Axial cracks were selected for evaluation in this analysis because of their potential to propagate to the weld region. Axial ID and OD part through-wall crack sizes equal the smallest crack sizes successfully detected by UT under the EPRI MRP Inspection Demonstration Program. Through-wall cracks were sized based on the stress distribution in the area of interest. The ID and OD part through-wall and through-wall cracks were located along the circumference of each nozzle at the 0° (downhill), 900 (mid-plane), and 1800 (uphill) azimuthal locations, 00 (downhill) being the furthest point from the center of the RPV head.

The analyses performed in the engineering evaluation were designed to determine the behavior of postulated cracks that could exist in the blind zone.

Hence, the crack growth region is from the top of the blind zone to the bottom of the weld. The fracture mechanics evaluation shows that an ID-initiated flaw will not grow through-wall and reach into the weld establishing a leak path within one cycle of operation for any of the nozzle locations.

Twenty-eight (28) different cases were analyzed using crack growth rates from EPRI Report MRP-55, Material Reliability Program - Crack Growth Rates for Evaluating Primary Water Stress Corrosion Cracking (PWSCC) of Thick-Wall Alloy 600 Material. In summary, the evaluation results from all cases at the uphill and mid-plane locations indicate that axial cracks in the blind zone will not propagate into the weld region within one cycle of operation. However, in two cases, postulated through-wall cracks at the 0° and the downhill location of the 8.80 CEDM nozzles were predicted to propagate into the weld in less than one cycle of operation. In two other cases fracture mechanics evaluations could not be performed for OD part through-wall and through-wall cracks at the downhill location of the 49.60 CEDM nozzle due to the extension of the weld into the blind zone. Results of the fracture mechanics evaluations for predicted crack growth are documented in Table 19 of Engineering Report M-EP-2003-002, Rev. 1 and are summarized in Table 3.

Based on the results of the fracture mechanics evaluation presented in Table 3, the downhill location of ANO-2 CEDM nozzles is the critical location at which a crack could potentially grow from the blind zone to the bottom of the weld in less than one cycle of operation. To assess this crack growth potential at the downhill location of the CEDM nozzles, results from the fracture mechanics analysis were evaluated against UT data obtained from inspection of all eighty-one (81) CEDM nozzles.

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Analysis to Determine Needed Available Crack Propagation Lengths CEDM nozzles that lack sufficient available crack propagation length will be inspected. For these nozzles, additional analysis was performed to determine how much additional length in the blind zone is required to ensure one cycle of crack growth without compromising the weld. See Figure 4.

The augmented inspection ensures that this additional area in the blind zone is free of PWSCC, thereby providing additional assurance that a crack in the blind zone will not propagate into the weld in less than one cycle of operation. The augmented inspection will utilize the ECT and/or PT examination method(s).

Because analysis has excluded the nozzle ID and a portion of the nozzle OD circumference as locations of unacceptable crack growth, the area of interest is limited to the OD of the downhill azimuthal region of the nozzle.

The boundaries for augmented inspection were established by fracture mechanics. The top of the augmented inspection zone was defined by the upper limit of the blind zone (1.544 inches above the bottom of the nozzle). The bottom and circumferential extent of the augmented inspection zone was determined by analysis. The bottom of the augmented inspection zone was established by first identifying a point at the downhill (00) azimuthal location from which a crack could not propagate into the weld region within one cycle of operation. Likewise, the circumferential extent of the augmented inspection zone was established by identifying a point along the upper limit of the blind zone from which a crack could not propagate into the weld region in one cycle of operation. Based on the results of this evaluation, augmented inspection zone boundaries were established as shown in Table 1.

As shown in Table 1, the circumferential extent of the augmented surface inspection is less than 3600 for the CEDM nozzles located at the 8.80, 28.80, and 49.60 head angle. By limiting the inspection to that portion of the nozzle defined by analysis, the effective radiation dose on inspection team personnel will be minimized while providing assurance that PWSCC will not cause a leak during the operating cycle following the inspection.

Updated Evaluation At the time that the fracture mechanics analysis in Engineering Report No. M-EP-2003-002 was performed, the only UT data available was that obtained during the ANO-2 spring 2002 refueling outage. To ensure that the FEA adequately modeled the as-built configuration of the selected ANO-2 CEDM nozzles, detailed design drawings and UT inspection data from the ANO-2 spring 2002 refueling outage was used for the design input. The ANO-2 spring 2002 UT examinations were performed prior to the first issuance of the Order and, although the examination procedure endeavored to examine the nozzle to below the bottom of the weld, they were not focused on driving the transducer to the lowest point that meaningful data could be collected. The ANO-2 fall 2003 UT examinations were performed after the first issuance of the Order and, due to the coverage area specified in the Order, the examination procedure did focus on driving the transducer to the lowest point that meaningful data could Page 11 of 24

be collected. As a result, Entergy confirmed by the 2003 UT data that some nozzles could be examined to a lower point than the 2002 data could support.

The 2003 data indicates that the available propagation lengths used in Engineering Report M-EP-2003-002 were conservative; that is, the actual lengths are longer.

Entergy performed an updated evaluation using the same analysis methodology documented in M-EP-2003-002 applied to the CEDM available propagation lengths based on the fall 2003 UT data. The results of this updated evaluation indicate that 24 CEDM nozzles have adequate available propagation lengths and, thus, meet Section IV.C.2.a, above. Therefore, 57 of the 81 CEDM nozzles will be inspected as described in Section IV.B.3, above. The updated evaluation results are provided in Table 4.

This analysis incorporated a crack-growth formula different from that described in Footnote 1 of the Order, as provided in EPRI Report MRP-55. Entergy is aware that the NRC staff has not yet completed a final assessment regarding the acceptability of the EPRI report. If the NRC staff finds that the crack-growth formula in MRP-55 is unacceptable, Entergy shall revise its analysis that justifies relaxation of the Order within 30 days after the NRC informs Entergy of an NRC-approved crack-growth formula. If Entergy's revised analysis shows that the crack growth acceptance criteria would be exceeded during a single operating cycle, this relaxation is rescinded and Entergy will, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, submit to the NRC written justification for continued operation. If the revised analysis shows that the crack growth acceptance criteria would be exceeded during a single operating cycle, Entergy shall, within 30 days, submit the revised analysis for NRC review. If the revised analysis shows that the crack growth acceptance criteria would not be exceeded during a single operating cycle, Entergy shall, within 30 days, submit a letter to the NRC confirming that its analysis has been revised. And any future crack-growth analyses performed for Operating Cycle 19 and future cycles for RPV head penetrations would be based on the new NRC-acceptable crack growth rate formula.

3. Auamented Inspections As discussed in Section IV.B.3, above, OD surface examinations are needed due to the inability of the UT probes to inspect the extent of the CEDM nozzles as required by the Order. The Order recognizes and allows combining techniques per Section IV.C.(5)(b)(iii) of the Order.

Table 1 specifies the minimum axial lengths and circumferential extents that must be examined for each nozzle group location. Table 2 provides individual nozzle information. Tables 1 and 2 indicate the minimum OD axial lengths range from 0.320 inch to 0.661 inch below the top of the blind zone.

During the fall 2003 and spring 2005 augmented inspections of the CEDM nozzles, Entergy performed manual ECT to examine the OD surface of the selected CEDM nozzles. Entergy was able to attain greater coverage than the minimum criteria specified in Table 1. Specifically, Entergy attained axial coverage of approximately 0.8 inch below the top of the blind zone. Entergy plans to continue using the manual ECT technique employed during the fall 2003 and spring 2005 augmented inspections.

Page 12 of 24

Entergy believes that by employing analytical and inspection techniques, the proposed alternative discussed above provides an adequate process for inspecting, evaluating, and determining the condition of the ANO-2 RPV head penetration CEDM nozzles with regard to the presence of PWSCC. Therefore, Entergy concludes that the proposed alternative adequately meets the intent of the Order.

V. CONCLUSION Section IV.F of the Order states in part:

Licensees proposing to deviate from the requirements of this Order shall seek relaxation of this Order pursuant to the procedure specified below. The Director, Office of Nuclear Reactor Regulation, may, in writing, relax or rescind any of the above conditions upon demonstration by the Licensee of good cause. A request for relaxation regarding inspection of specific nozzles shall also address the following criteria:

(1) The proposed alternative(s) for inspection of specific nozzles will provide an acceptable level of quality and safety, or (2) Compliance with this Order for specific nozzles would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

Section IV.C.(5)(b) of the Order establishes a minimum set of RPV head penetration nozzle inspection requirements to identify the presence of cracks in penetration nozzles that could lead to leakage of reactor coolant and wastage of RPV head material.

Entergy believes that compliance with the UT inspection provisions of Section IV.C.(5)(b)(i) of the Order as described in Section II above would result in hardships and unusual difficulties, as discussed in Section III above, without a compensating increase in the level of quality and safety.

Entergy believes the proposed alternative, described in Section IV, provides an acceptable level of quality and safety by utilizing inspections and supplemental analysis to determine the condition of the ANO-2 CEDM nozzles. The technical basis for the supplemental analysis and the augmented inspections of the proposed alternative is documented in Engineering Report M-EP-2003-002, Rev. 1, which was previously submitted to the NRC staff. Therefore, Entergy requests that the proposed alternative be authorized pursuant to Section IV.F of the Order for the remainder of the current (3rd) 10-year inservice inspection interval at ANO-2.

Page 13 of 24

TABLE 1 AUGMENTED SURFACE INSPECTION CRITERIA

.CEM Nozzle Boundry for Augmented Surface Examination Loca'tion Azimluth.

Atioh Top l Bottom i ,Axial Circumferential Elevation Elevation .. Length. Extent 2 00 Downhill 1.544' 1.090- 0.454" DH i 1800 8.80 Downhill 1.544" 1.090" 0.454" DH +/- 67.50 28.80 Downhill 1.544" 1.224" 0.320" DH +/- 22.50 49.60 Downhill 1.544" 0.883" 0.661' DH +/- 450 Notes:

1. Measured from the bottom end of the nozzle.
2. ODH" = 'downhill' Page 14 of 24

TABLE 2 EVALUATION OF CEDM NOZZLES FOR AUGMENTED INSPECTION CEDM Nozzle :Selected for Augmented Inspection Boundary Augmented . (referenced from bottom of nozzle)-

No.Head nspebctio~n()

No. HeadTop Bottom Axial --Azimuthal Location and Angle  : Elevation . Elevation', Length Circumferential Extent 1 00 Yes 1.544- 1.090' 0.454" Downhill i 1800 2 8.80 Yes 1.544" 1.090' 0.454" Downhill 67.50 3 8.8° Yes 1.544- 1.090' 0.454r Downhill 67.50 4 8.8° Yes 1.544- 1.090' 0.454" Downhill i 67.50 5 8.80 No'i) N/A N/A N/A N/A 6 12.40 No = N/A N/A N/A N/A 7 12.40 No N/A N/A N/A N/A 8 12.40 No ') N/A N/A N/A N/A 9 12.40 No ') N/A N/A N/A N/A 10 17.70 No = N/A N/A N/A N/A 11 17.70 Yes 1.544- 1.090" 0.454" Downhill +/- 67.50 12 17.70 No0 N/A N/A N/A N/A 13 17.70 No Z N/A N/A N/A N/A 14 19.90 Not" N/A N/A N/A N/A 15 19.90 No N/A N/A N/A N/A 16 19.90 Yes 1.544" 1.090" 0.454' Downhill +/- 67.50 17 19.90 Yes 1.544- 1.090- 0.454" Downhill +/- 67.50 18 19.90 No Z N/A N/A N/A N/A 19 19.90 No N/A N/A N/A N/A 20 19.90 No N/A N/A N/A N/A 21 19.90 No . N/A N/A N/A N/A 22 25.50 No } N/A N/A N/A N/A 23 25.50 Yes 1.544" 1.090- 0.454" Downhill +/- 67.50 24 25.50 Yes 1.544" 1.090' 0.454" Downhill +/- 67.50 25 25.50 No W N/A N/A N/A N/A 26 27.20 Yes 1.544" 1.090" 0.454" Downhill +/- 67.50 27 27.2° Yes 1.544" 1.090" 0.454" Downhill +/- 67.50 28 27.20 Yes 1.544" 1.090" 0.454" Downhill +/- 67.50 29 27.20 Yes 1.544" 1.090" 0.454" Downhill +/- 67.50 30 28.80 No " N/A N/A N/A N/A 31 28.80 No'W N/A N/A N/A N/A 32 28.80 No N/A N/A N/A N/A 33 28.80 No i N/A N/A N/A N/A 34 28.80 No T' N/A N/A N/A N/A 35 28.80 No N/A N/A N/A N/A 36 28.80 No i N/A N/A N/A N/A 37 28.80 No M N/A N/A N/A N/A 38 33.30 Yes 1.544- 0.883" 0.661- Downhill +/- 45.00 39 33.30 Yes 1.544- 0.883' 0.661' Downhill +/- 45.00 40 33.30 Yes 1.544- 0.883- 0.661" Downhill +/- 45.00 41 33.30 Yes 1.544- 0.883- 0.661" Downhill +/- 45.00 42 33.30 Yes 1.544" 0.883- 0.661" Downhill +/- 45.00 43 33.30 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 44 33.30 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 Page 15 of 24

CEDM Nozzle Selected for Augmented Inspection Boundary Augmented ;_i_;___._ (referenced from bottom of nozzle)

No. - Head Inspection ci Top 3/4,~ BOttom Axal Azimuthal ~Locationan

__ Angle I._ _ Elevation. Elevation Length Circumferential Extent 45 33.30 Yes 1.544" 0.883' 0.661- Downhill 45.00 46 37.60 Yes 1.544" 0.883- 0.661- Downhill 45.00 47 37.60 Yes 1.544- 0.883- 0.661- Downhill 45.00 48 37.60 Yes 1.544" 0.883- 0.661- Downhill 45.00 49 37.60 Yes 1.544" 0.883- 0.661" Downhill i 45.00 50 38.90 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 51 38.90 Yes 1.544" 0.883- 0.661" Downhill i 45.00 52 38.90 Yes 1.544" 0.883" 0.661" Downhill i 45.00 53 38.90 Yes 1.544- 0.883- 0.661- Downhill 45.0° 54 38.9° Yes 1.544" 0.883- 0.661" Downhilli 45.00 55 38.90 Yes 1.544" 0.883- 0.661- Downhill 45.0° 56 38.90 Yes 1.544" 0.883" 0.661- Downhill 45.00 57 38.90 Yes 1.544" 0.883" 0.661- Downhill 45.00 58 40.30 Yes 1.544" 0.883" 0.661- Downhill 45.0 0 59 40.30 Yes 1.544" 0.883" 0.661" Downhill 45.00 60 40.30 Yes 1.544" 0.883" 0.661" Downhill 45.00 61 40.30 Yes 1.544- 0.883" 0.661- Downhill 45.00 62 43.00 Yes 1.544- 0.883" 0.661" Downhill 45.00 63 43.00 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 64 43.00 Yes 1.544" 0.883- 0.661" Downhill i 45.00 65 43.00 Yes 1.544- 0.883" 0.661" Downhill +/- 45.00 66 43.00 Yes 1.544- 0.883" 0.661" Downhill +/- 45.00 67 43.00 Yes 1.544- 0.883" 0.661" Downhill +/- 45.00 68 43.00 Yes 1.544" 0.883" 0.661- Downhill +/- 45.00 69 43.00 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 70 49.60 Yes 1.544" 0.883" 0.661- Downhill +/- 45.00 71 49.60 Yes 1.544" 0.883" 0.661- Downhill +/- 45.00 72 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.0° 73 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 74 49.60 Yes 1.544- 0.883" 0.661- Downhill +/- 45.00 75 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 76 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 77 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 78 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 79 49.6° Yes 1.544- 0.883" 0.661" Downhill +/- 45.00 80 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 81 49.60 Yes 1.544" 0.883" 0.661" Downhill +/- 45.00 Notes for Table 2:

1. CEDM nozzles are subject to augmented inspection under either of the following conditions:
  • Postulated cracks can grow from the blind zone into the weld within one cycle of plant operation
  • The nozzle attachment weld extends into the blind zone region.
2. This nozzle is excluded from augmented inspection based on the fracture mechanics evaluation and available crack propagation length (see Table 4).

Page 16 of 24

TABLE 3 RESULTS OF CRACK GROWTH ANALYSIS CEDM . Nozzle Axial Crack CrackEvaluation Results .'

Location ' :Azimuth Evaluated (Head Angle) 'Location 00 All ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Less than I Cycle to reach Weld 8.8° Downhill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Less than I Cycle to reach Weld Uphill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld Mid-plane ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld 28.80 Downhill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld Uphill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld Mid-plane ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld 49.60 Downhill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Not analyzed - weld extends Into blind zone Through-wall Not analyzed - weld extends Into blind zone Uphill ID Part through-wall Greater than 1 Cycle to reach Weld OD Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld Mid-plane ID Part through-wall Greater than 1 Cycle to reach Weld 0D Part through-wall Greater than 1 Cycle to reach Weld Through-wall Greater than 1 Cycle to reach Weld Page 17 of 24

TABLE 4 CEDM NOZZLES AUGMENTED INSPECTION Penetration Analytical Crack; Available Crack Growth e'd Growth Per Propagation Length- Into Weld

o. Hea CycIe(1) Based on UT Data(4) Within i Cycle Angle -______;_: _  ;,;_._:

1 O 0.576' 0.520" Yes 2 8.80 0.560- 0.320" Yes 3 8.8° 0.560- 0.440" Yes 4 8.8° 0.560- 0.480" Yes 5 8.8° 0.560' 0.600" No 6 12.40 0.560" (" 0.760" No 7 12.40 0.560"' 0.800" No 8 12.40 0.560-' 0.560" No 9 12.40 0.560' 0.800" No 10 17.70 0.5607' 0.680" No 11 17.70 0.560""' 0.520" Yes 12 17.7° 0.560' 0.640" No 13 17.70 0.560"' 0.800" No 14 19.9° 0.560""' 0.720" No 15 19.90 0.560""' 0.640" No 16 19.90 0.560""' 0.440" Yes 17 19.90 0.560""' 0.520" Yes 18 19.90 0.560""' 0.600" No 19 19.90 0.560""' 0.720" No 20 19.90 0.560"' 0.800" No 21 19.90 0.560""' 0.840" No 22 25.50 0.560' 0.560" No 23 25.50 0.560"' 0.280" Yes 24 25.5° 0.560 "' 0.480" Yes 25 25.50 0.560"' 0.720" No 26 27.20 0.560"' 0.440" Yes 27 27.20 0.560"' 0.320" Yes 28 27.20 0.560""' 0.520" Yes 29 27.20 0.560""' 0.480" Yes 30 28.80 0.086" 0.520" No 31 28.80 0.086-' 0.440" No 32 28.80 0.086""' 0.320" No 33 28.8° 0.086-' 0.280" No 34 28.80 0.086"' 0.520" No 35 28.80 0.086- " 0.600" No 36 28.80 0.086"' 0.480" No 37 28.80 0.086"' 0.720" No 38 33.30 (3) 0.320" Yes 39 33.30 (3) 0.000" Yes 40 33.30 (3) 0.000" Yes 41 33.30 (3) 0.000" Yes Page 18 of 24

Penetration Analytical Crack: Available:' tCrack Growth

- Growth Per Propagation Length Into Weld No. Head Cycle , , Based on UT Data(4) Within I Cycle Ang le 42 33.30 (3) 0.280" Yes 43 33.30 (3) 0.000" Yes 44 33.30 (3) 0.360" Yes 45 33.30 (3) 0.000" Yes 46 37.60 (3) 0.000" Yes 47 37.60 (3) 0.000" Yes 48 37.60 (3) 0.000" Yes 49 37.60 (3) 0.160" Yes 50 3590 (3) 0.360" Yes 51 38.90 (3) 0.360" Yes 52 38.90 (3) 0.000" Yes 53 38.90 (3) 0.000" Yes 54 38.90 (3) 0.000" Yes 55 38.90 (3) 0.160" Yes 56 38.90 (3) 0.280" Yes 57 38.90 (3) 0.000" Yes 58 40.30 (3) 0.520" Yes 59 40.3° (3) 0.360" Yes 60 40.30 (3) 0.240" Yes 61 40.30 (3) 0.320" Yes 62 43.00 (3) 0.440" Yes 63 43.00 (3) 0.320" Yes 64 43.00 (3) 0.320" Yes 65 43.00 (3) 0.240" Yes 66 43.00 (3) 0.1 60" Yes 67 43.00 (3) 0.360" Yes 68 43.00 (3) 0.280" Yes 69 43.0° (3) 0.320" Yes 70 49.60 (3) 0.400" Yes 71 49.60 (3) 0.400" Yes 72 49.60 (3) 0.160" Yes 73 49.6° (3) 0.000" Yes 74 49.60 (3) 0.400" Yes 75 49.6° (3) 0.320" Yes 76 49.60 (3) 0.000" Yes 77 49.60 (3) 0.000" Yes 78 49.60 (3) 0.360" Yes 79 49.60 (3) 0.000" Yes 80 49.60 (3) 0.200" Yes 81 49.60 (3) 0.000" Yes Page 19 of 24

Notes for Table 4:

1. Crack Growth Distance per Cycle is taken from Table 19 of the Engineering Report.
2. CEDM nozzles at the 12.40, 17.70, 19.90, 25.50, and 27.20 locations are evaluated for the predicted crack growth on CEDM nozzles at the 8.80 nozzle location since it is larger than the predicted crack growth on CEDM nozzles at the 28.80 nozzle location.
3. CEDM nozzles at the 33.30, 37.60, 38.90, 40.30, and 43.00 locations must be bounded by fracture mechanics analysis results on CEDM nozzles at the 49.60 nozzle locations.

Because certain nozzles in these groups have welds that extend into the blind zone at the downhill azimuthal location, a bounding fracture mechanics analysis could not be performed for the OD part-through-wall and through-wall cracks. Therefore, the nozzles in these groups will be inspected.

4. The "Available Propagation Length Based on UT Data" is based on UT data obtained during the ANO-2 fall 2003 refueling outage.

Page 20 of 24

900 lI Q U Q  ! Q Q

\ a S@//6, 0 8 a @SS" a 6 a

\Vents )()()

00 FIGURE 1 PENETRATION LOCATIONS IN THE ANO-2 RPV HEAD Page 21 of 24

R1EACTOR -

VRtSSAEL yt sSCI

'echO CONE OtAtI 'A' CEDM NOZZLE TYPICAL CEDM NOZZLE DETAIL W/ GUIDE CONE DETAIL DETAIL "A" FIGURE 2 TYPICAL CEDM NOZZLE DETAILS Page 22 of 24

CEDM Nozzle 0.200-

- Dead Band I. ._._..- - .- ... .

0 Threaded Connection and Chamfer 0._..S.

Region UT Inspection Probe Schematic See table below for transducer information.

Guide Cone Nozzle Position. Mode Diameter Description,,

1 Transmit 0.25 inch Circumferential Scan Using TOFD 2 Receive 0.25 inch Circumferential Scan Using TOFD 3 Transmit 0.25 inch Axial Scan Using TOFD 4 Receive 0.25 inch Axial Scan Using TOFD 5 Transmit 0.25 inch Standard Zero Degree Scan Receive 6 Transmit 0.25 inch Low Frequency Eddy Current Receive 7 N/A 0.25 inch Eddy Current FIGURE 3 TYPICAL UT INSPECTION PROBE DETAIL Page 23 of 24

CEDM Nozzle RPV Head Inspectable Region J-Groove Welds r

Blind Zone 1.544" Crack A

CEDM Guide Cone FIGURE 4 DETAIL OF CEDM NOZZLE CRACK GROWTH ANALYSIS Page 24 of 24

ENCLOSURE 2 CNRO-2005-00048 LICENSEE-IDENTIFIED COMMITMENTS to CNRO-2005-00048 Page 1 of 1 LICENSEE-IDENTIFIED COMMITMENTS TYPE (Check one) SCHEDULED ONE-TIME CONTINUING COMPLETION COMMITMENT ACTION COMPLIANCE DATE

1. As required by Section IV.E of the Order, the 60 days after final results of the inspections will be provided startup from in the 60-day report submitted to the NRC. each refueling outage
2. If the NRC staff finds that the crack-growth Within 30 days formula in MRP-55 is unacceptable, Entergy after the NRC shall revise its analysis that justifies relaxation informs Entergy of the Order within 30 days after the NRC of an NRC-informs Entergy of an NRC-approved crack- approved crack-growth formula. growth formula.
3. If Entergy's revised analysis shows that the Within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> crack growth acceptance criteria would be from completing exceeded during a single operating cycle, this the revised relaxation is rescinded and Entergy will, within analysis in #2, 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, submit to the NRC written justification above.

for continued operation.

4. If the revised analysis shows that the crack Within 30 days growth acceptance criteria would be exceeded from completing during a single operating cycle, Entergy shall, the revised within 30 days, submit the revised analysis for analysis in #2, NRC review. above.
5. Ifthe revised analysis shows that the crack Within 30 days growth acceptance criteria would not be from completing exceeded during a single operating cycle, the revised Entergy shall, within 30 days, submit a letter to analysis in#2, the NRC confirming that its analysis has been above.

revised.

6. If the NRC staff finds that the crack-growth N/A formula in MRP-55 is unacceptable, any future crack-growth analyses performed for RPV head penetrations will be based on the new NRC-acceptable crack growth rate formula.
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