CNL-15-236, Revised Response to NRC Request for Additional Information Regarding American Society of Mechanical Engineers Section XI, Inservice Inspection and Augmented Program, Second Ten Year Interval Request for Relief 1-ISI-27

Revised Response to NRC Request for Additional Information Regarding American Society of Mechanical EngineersSection XI, Inservice Inspection and Augmented Program, Second Ten Year Interval Request for Relief 1-ISI-27

ML15338A221
Person / Time
Site:	Browns Ferry
Issue date:	11/18/2015
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CAC MF6401, CNL-15-236
Download: ML15338A221 (4)

Text

L44 15118 002 Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-15-236 November 18, 2015 10 CFR 50.55a ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Browns Ferry Nuclear Plant, Unit 1 Renewed Facility Operating License No. DPR-33 NRC Docket No. 50-259

Subject:

Revised Response to NRC Request for Additional Information Regarding Browns Ferry Nuclear Plant, Unit 1, American Society of Mechanical EngineersSection XI, Inservice Inspection and Augmented Program, Second Ten Year Interval Request For Relief 1-ISI-27 (CAC No. MF6401)

References:

1. Letter from TVA to NRC, CNL-15-125, Browns Ferry Nuclear Plant (BFN)

Unit 1, American Society of Mechanical Engineers (ASME)Section XI, Inservice Inspection (ISI) and Augmented Program, Second Ten Year Interval Request For Relief 1-ISI-27, dated June 26, 2015 (ML15181A448)

2. Letter from NRC to TVA, Browns Ferry Nuclear Plant, Unit 1 - Request for Additional Information Related to Relief Request for the Use of Alternatives to Certain American Society of Mechanical Engineers, Boiler and Pressure Vessel Code,Section XI Requirements (CAC No. MF6401)

(CNL-15-125), dated October 6, 2015 (ML15274A574)

3. Letter from TVA to NRC, CNL-15-215, Response to NRC Request for Additional Information Regarding Browns Ferry Nuclear Plant, Unit 1, American Society of Mechanical EngineersSection XI, Inservice Inspection and Augmented Program, Second Ten Year Interval Request For Relief 1-ISI-27 (CAC No. MF6401), dated October 27, 2015 By letter dated June 26, 2015 (Reference 1), Tennessee Valley Authority (TVA) submitted a request for an alternative from inservice inspection (1-ISI-27), pertaining to Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)

Code for Browns Ferry Nuclear Plant (BFN), Unit 1. The proposed alternative would provide relief from reactor vessel circumferential weld examinations currently required by ASME Code for the period of extended operation ending December 20, 2033.

U.S. Nuclear Regulatory Commission CNL-15-236 Page 2 November 18. 2015 By letter dated October 6. 2015 , the Nuclear Regulatory Commission (NRC) sent a request for additional information (RAJ ) (Reference 2). By letter dated October 27 (Reference 3),

TVA provided a response to the RA J rev ising a fluence value in a table from Reference 1.

During a follow-up teleconference with the NRC . it was determined that two additional values should have been revised based on the fluence value correction . The enclosure to this letter provides TVA's revised response to the NRC RAI. The revised response supersedes . in entirety . the response provided in Reference 3.

There are no new regulatory commitm ents contained in this subm ittal. Please address any questions regarding this submitta l to Mr. Jam ie L. Paul at (256) 729-2636 .

Enclosure :

Revised Response to NRC Request for Additional Information Regard ing Browns Ferry Nuclear Plant. Unit 1. American Society of Mechanical Eng ineersSection XI ,

lnservice Inspection and Augmented Program . Second Ten Year Interval Request For Relief 1-ISl-27 cc (Enclosure ):

NRC Regional Admin istrator - Reg ion II NRC Senior Resident Inspector - Browns Ferry Nuclear Plan t NRC Project Manager - Browns Ferry Nuclear Plant

ENCLOSURE Revised Response to NRC Request for Additional Information Regarding Browns Ferry Nuclear Plant, Unit 1, American Society of Mechanical EngineersSection XI, Inservice Inspection and Augmented Program, Second Ten Year Interval Request For Relief 1-ISI-27 NRC RAI No. 1 The fluence value used in the June 26, 2015 request is based on the December 18, 2013 license amendment request.

The staff noted that the fluence at the clad-to-base metal interface in Table 3 of the June 26, 2015 submittal does not match that from Table B-5 of the December 18, 2013 license amendment request.

Clarify the above inconsistency and revise the June 26, 2015 letter (as needed) to accurately reflect the fluence on the beltline, circumferential (girth) weld.

TVA Response Information from NUREG-1843 (Reference 1), Section 4.2.6.2, was provided as the basis for the June 26, 2015, request for relief. The table from NUREG-1843 comparing BFN Unit 1 Reactor Vessel (RV) limiting weld parameters to those used in the NRC evaluation of the BWRVIP-05 Report (Reference 2) was included as Table 2 of the request. The fluence values provided in the table correspond to the Peak I.D. fluence.

Table 3 of the request includes a comparison of the BWRVIP-05 data with revised BFN Unit 1 RV limiting circumferential weld parameters based upon revised BFN Unit 1 P/T curves from a December 18, 2013, License Amendment Request (LAR) (Reference 3). The value of 0.0886 provided for Fluence at Clad/Weld Interface 1019 n/cm2 in Table 3 of the request is the 38 EFPY 1/4T fluence value and not the Peak I.D. fluence value. This inconsistency was entered into the TVA corrective action program as CR #1095049.

Table 3 of the request is revised to remove the inconsistency by replacing the 38 EFPY 1/4T fluence value of 0.0886E+19 n/cm2 with the 38 EFPY Peak I.D. fluence of 0.128E+19 n/cm2 from Table B-5 of Enclosure 2 of the Reference 3 LAR.

The Delta RTNDT Without Margin and Mean RTNDT values are affected by the change in fluence value. The revised value for Delta RTNDT Without Margin was determined using Equation 2 from Regulatory Guide 1.99 (Reference 4). The Mean RTNDT is the sum of the revised Delta RTNDT and the Initial RTNDT. Table 3 is revised to include the new values for Delta RTNDT Without Margin and Mean RTNDT.

E-1

TABLE 3 Group B&W 64 BFN Unit 1 EFPY 38 EFPY Cu % 0.31 0.27 Ni % 0.59 0.6 CF 196.7 184 Fluence at Clad/Weld Interface 1019 n/cm2 0.19 0.128 Delta RTNDT Without Margin (ºF) 109.4 86.1 Initial RTNDT (ºF) 20 20 Mean RTNDT (ºF) 129.4 106.1 P (F/E) NRC 4.83 x 104 -

P (F/E) BWRVIP - -

References:

1. NUREG-1843, Safety Evaluation Report Related to the License Renewal of the Browns Ferry Nuclear Plant, Units 1, 2, and 3, April 2006

2. NRC letter from Gus. C. Lainas to Carl Terry, Niagara Mohawk Power Company, BWRVIP Chairman, Final Safety Evaluation of the BWRVIP Vessel and Internals Project BWRVIP-05 Report, (TAC No. M93925), July 28, 1998

3. Letter from TVA to NRC, CNL-13-148, Browns Ferry Nuclear Plant (BFN), Unit 1 -

Application to Modify Technical Specifications 3.4.9, RCS Pressure and Temperature (P/T) Limits (BFN TS-484), dated December 18, 2013 (ML13358A067)

4. Regulatory Guide 1.99, Revision 2, Radiation Embrittlement of Reactor Vessel Materials, U.S. Nuclear Regulatory Commission Office of Nuclear Regulatory Research, May 1988 E-2