NL-14-013, Additional Information Regarding the License Renewal Application - Action Item 7 from MRP-227-A

Additional Information Regarding the License Renewal Application - Action Item 7 from MRP-227-A

ML14038A150
Person / Time
Site:	Indian Point
Issue date:	01/28/2014
From:	Dacimo F Entergy Nuclear Northeast
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-14-013
Download: ML14038A150 (8)

Text

Enterav Nuclear Northeast Indian Point Energy Center 450 Broadway, GSB P.O. Box 249 Buchanan, NY 10511-0249 Tel (914) 254-2055 Fred Dacimo Vice President Operations License Renewal NL-14-013 January 28, 2014 U.S. Nuclear Regulatory Commission Document Control Desk 11545 Rockville Pike, TWFN-2 F1 Rockville, MD 20852-2738

SUBJECT:

Additional Information Regarding the License Renewal Application -

Action Item 7 from MRP-227-A Indian Point Nuclear Generating Unit Nos. 2 & 3 Docket Nos. 50-247 and 50-286 License Nos. DPR-26 and DPR-64

REFERENCES:

1. NRC letter, "Summary of Conference Call held on December 18, 2013, between the U.S. Nuclear Regulatory Commission and Entergy Nuclear Operations, Inc., Concerning Applicant/Licensee Action Item 7 from MRP-227-A" dated January 9, 2014.

2. Entergy letter, NL-13-122, "Reply to Request for Additional Information Regarding the License Renewal Application" dated September 27, 2013.

Dear Sir or Madam:

Entergy Nuclear Operations, Inc is providing, in the enclosure, additional information pertaining to NRC review of the License Renewal Application (LRA) for Indian Point 2 (IP2) and Indian Point 3 (IP3). The additional information is being provided as a follow up to a recent conference call between Entergy and the NRC regarding Action Item 7 from MRP-227-A, as documented in Reference 1. The NRC letter notes that the NRC is considering an alternative approach for cast austenitic stainless steel (CASS) components that may impact Commitment 47. This alternative approach would be based on ferrite content derived from certified material test reports (CMTRs) for CASS components. There are 96 columns with CASS caps in the lower internals assembly of each Indian Point unit. As noted on the call, CMTRs are available for all of the IP3 CASS caps. As documented in the enclosure attached to this letter, Entergy can now confirm that CMTRs are also available for all of the IP2 CASS caps, and that the IP2 and IP3 column caps are of low molybdenum CF8 material. As noted in Reference 2, no special casting processes were designated; thus, it was conservatively assumed that the lower core support column caps were statically cast.

Docket Nos. 50-247 & 50-286 NL-14-013 Page 2 of 2 There are no new regulatory commitments in this submittal.

I declare Ondeq penalty of perjury that the foregoing is true and correct. Executed on 2014.

Since FRD/rw

Enclosure:

LTR-RIAM-14-2, Revision 0, Attachment 1, "Summary of the Evaluation of Indian Point Units 2 and 3, Lower Internals Assembly, Column Caps - Ferrite Content and Susceptibility to Thermal Embrittlement" cc: Mr. William Dean, Regional Administrator, NRC Region I Mr. Sherwin E. Turk, NRC Office of General Counsel, Special Counsel Mr. Dave Wrona, NRC Branch Chief, Engineering Review Branch I Ms. Kimberly Green, NRC Sr. Project Manager, Division of License Renewal Mr. Douglas Pickett, NRR Senior Project Manager Ms. Bridget Frymire, New York State Department of Public Service NRC Resident Inspector's Office Mr. Francis J. Murray, Jr., President and CEO NYSERDA

ENCLOSURE TO NL-14-013 LTR-RIAM-14-2, Revision 0, Attachment 1, "Summary of the Evaluation of Indian Point Units 2 and 3, Lower Internals Assembly, Column Caps - Ferrite Content and Susceptibility to Thermal Embrittlement" ENTERGY NUCLEAR OPERATIONS, INC.

INDIAN POINT NUCLEAR GENERATING UNIT NOS. 2 & 3 DOCKET NOS. 50-247 AND 50-286

Westinghouse Non-Proprietary Class 3 Attachment I Page 1 of 5 Our ref: LTR-RIAM-14-2, Rev. 0 January 10, 2014 : Summary of the Evaluation of Indian Point Units 2 and 3, Lower Internals Assembly, Column Caps - Ferrite Content and Susceptibility to Thermal Embrittlement

© 2014 Westinghouse Electric Company LLC All Rights Reserved

Westinghouse Non-Proprietary Class 3 Attachment I Page 2 of 5 Our ref: LTR-RIAM- 14-2, Rev. 0 January 10, 2014 Summary of the Evaluation of Indian Point Units 2 and 3, Lower Internals Assembly, Column Caps - Ferrite Content and Susceptibility to Thermal Embrittlement Background and Purpose The Reactor Vessel Internals (RVI) Program at Indian Point Units 2 and 3 is based on MRP-227-A (Reference 1) and is the base program that addresses the RVI components that require aging management and it specifies inspection requirements. The Thermal Aging and Neutron Irradiation Embrittlement of Cast Austenitic Stainless Steel (CASS) Program at Indian Point (IPEC LRA (Reference 2) augments the RVI program by evaluating the potential susceptibility to thermal embrittlement (TE) of plant-specific CASS components.

The delta ferrite content of the CASS component is calculated using Hull's formula (as applied to CASS material in Reference 3) with input of element percentages from the component-specific chemistry from either the material specification or from the certified material test report (CMTR) for the material. The NRC screening criteria for TE (Reference 4, Table 2) is based on chemistry, casting method, and the delta-ferrite content.

This is an evaluation of the susceptibility to TE of the Indian Point Units 2 and 3 CASS column caps.

These CASS column caps are part of the support columns in the lower internals assembly. There are 96 columns with CASS caps in the lower internals assembly of each Indian Point Unit. Figure 1 is an illustration of the column with its CASS cap. This Indian Point-specific component, lower internals assembly - column cap, correlates to the MRP-227-A, lower support assembly, lower support column bodies (cast) component.

• Figure 1 Support Column with CASS Cap (cast cap is shown as shaded)

Westinghouse Non-Proprietary Class 3 Attachment I Page 3 of 5 Our ref: LTR-RIAM-14-2, Rev. 0 January 10, 2014 Indian Point Unit 2. Lower Internals Assembly Column Cap - Ferrite Content and Thermal Embrittlement Evaluation The Indian Point Unit 2 lower internals assembly - column caps were cast from ASTM A296, Grade CF8 material (Reference 5). The elemental percentages from the CMTRs, for the Indian Point Unit 2, CASS column caps, are input into Hull's formula (per Reference 3 guidance) to calculate the delta ferrite content of the CASS material. The Indian Point Unit 2 CMTRs do not list the element percentage for nitrogen; thus, per the guidance of Reference 3, nitrogen is assumed to be 0.04 percent. The CMTRs do not list an elemental percentage for molybdenum. ASTM A296, Grade CF8 did not have a requirement for percent molybdenum and that specification was withdrawn in 1977. The current ASTM A351-13, Grade CF8 chemistry requirements specify a maximum of 0.5 percent molybdenum; thus, this maximum value is input into Hull's formula.

The Westinghouse records show that six different heats of material were used to produce 97 CASS caps that were released for use in the fabrication of the 96 Indian Point Unit 2 columns in the lower internals assembly columns. The records do not show exactly which cast cap, out of the 97, was used on each of the 96 columns. The calculated ferrite contents are listed in Table 1. The maximum ferrite content is 14.6 percent, the minimum is 6.4 percent, and the mean ferrite content is 10.5 percent.

The TE screening of Indian Point Unit 2, CASS column caps is shown in Table 2. The Indian Point Unit 2 column caps are of low molybdenum CF8 material, are assumed static cast, and have maximum ferrite content 14.6 percent which is less than the 20 percent screening level. Therefore, consistent with the NRC criteria of Reference 4, it is concluded that the Indian Point Unit 2 lower internals assembly, column caps are not susceptible to TE.

Table 1 Indian Point Unit 2 Lower Internals Assembly - Column Caps Heat and Ferrite Content Quantity of Calculated Ferrite Content Supplier Heat Number CASS Caps (Percent)

L14 23 8.1 L25 25 12.4 L35 20 14.6 L54 14 6.4 L60 7 10.3 L217 8 7.8 Table 2 TE Screening of Indian Point Unit 2 Lower Internals Assembly -

Column Cans

Westinghouse Non-Proprietary Class 3 Attachment I Page 4 of 5 Our ref: LTR-RIAM-14-2, Rev. 0 January 10, 2014 Indian Point Unit 3. Lower Internals Assembly Column Cap - Ferrite Content and Thermal Embrittlement Evaluation The Indian Point Unit 3 lower internals assembly - column caps were cast from ASTM A296 Grade CF8 material (Reference 6). The elemental percentages from the CMTRs, for the Indian Point Unit 3, CASS column caps, are input into Hull's formula (per Reference 3 guidance) to calculate the delta ferrite content of the CASS material. The Indian Point Unit 3 CMTRs do not list the element percentage for nitrogen; thus, per the guidance of Reference 3, nitrogen is assumed to be 0.04 percent. The CMTRs typically do not list an elemental percentage for molybdenum. There are isolated cases where the Indian Point Unit 3 records do list the molybdenum percentage, which ranges from 0.14 to 0.36 percent, depending on the material heat. Where the CMTRs do list the molybdenum percentage, the listed value is used in the calculation of ferrite content. ASTM A296, Grade CF8 did not have a requirement for percent molybdenum and the specification was withdrawn in 1977; thus, where the CMTRs do not list molybdenum, the current ASTM A351-13, Grade CF8 chemistry requirement of maximum 0.5 percent molybdenum is input into Hull's formula.

The Westinghouse records show that seven different heats of material were used to produce 97 CASS caps that were released for use in the fabrication of the 96 Indian Point Unit 3 lower internals assembly columns. The records do not show exactly which cast cap, out of the 97, was used on each of the 96 columns. The calculated ferrite contents are listed in Table 3. The maximum ferrite content is 11.8 percent, the minimum is 5.2 percent, and the mean ferrite content is 8.3 percent.

The TE screening of Indian Point Unit 3, CASS column caps is shown in Table 4. The Indian Point Unit 3, column caps are of low molybdenum CF8 material, are assumed static cast, and have maximum ferrite content 11.8 percent which is less than the 20 percent screening level. Therefore, consistent with the NRC criteria of Reference 4, it is concluded that the Indian Point Unit 3 lower internals assembly, column caps are not susceptible to TE.

Table 3 Indian Point Unit 3 Lower Internals Assembly - Column Caps Heat and Ferrite Content Supplier Heat Number Quantity of CASS Calculated Ferrite Content Caps (Percent)

L335 13 8.9 L347 21 7.7 L353 18 11.8 L355 6 7.9 L364 22 5.2 L370 4 5.3 L373 13 10.0 Table 4 TE Screening of Indian Point Unit 3 Lower Internals Assembly -

Column Caps

Westinghouse Non-Proprietary Class 3 Attachment I Page 5 of 5 Our ref: LTR-RIAM-14-2, Rev. 0 January 10, 2014 References

1. Materials Reliability Program. PressurizedWater ReactorInternals Inspection and Evaluation Guidelines (MRP-227-A). EPRI, Palo Alto, CA: 2011. 1022863.

2. Entergy Letter, NL-12-037, "License Renewal Application - Revised Reactor Vessel Internals Program and Inspection Plan Complaint with MRP-227-A, Indian Point Nuclear Generating Unit Nos. 2 and 3, Docket Nos. 50-247 and 50-286, License Nos. DPR-26 and DPR-64," February 17, 2012.

3. U.S. Nuclear Regulatory Commission NUREG/CR-4513, "Estimation of Fracture Toughness of Cast Stainless Steels During Thermal Aging in LWR Systems," August 1994. (Available NRC ADAMS Accession No. ML052360554).

4. U.S. Nuclear Regulatory Commission License Renewal Issue No. 98-0030, "Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Components," May 19, 2000. (Available NRC ADAMS Accession No. ML003717179).

5. Westinghouse Letter IPP-1 3-44, "Support for Reactor Vessel Internals Aging Management RAI Project Final Response to RAI 1 B Items 1, 2 and 3," October 16, 2013.

6. Westinghouse Letter INT-13-51, "Support for Reactor Vessel Internals Aging Management RAI Project Final Response to RAI 1 B Items 1, 2 and 3," October 16, 2013.