ML050120238

1/20/05, Wolf Creek Generating Station - Information Provided in E-mail Dated 1/7/05

ML050120238
Person / Time
Site:	Wolf Creek
Issue date:	01/20/2005
From:	Donohew J NRC/NRR/DLPM/LPD4
To:	NRC/NRR/DLPM
Donohew J N, NRR/DLPM,415-1307
References
TAC MC5407
Download: ML050120238 (4)

Text

January 20, 2005 MEMORANDUM TO: Docket File FROM: Jack N. Donohew, Project Manager for Wolf Creek /RA/

Project Directorate IV-2 Division of Licensing Project Management Office of Nuclear Reactor Regulation

SUBJECT:

INFORMATION PROVIDED IN E-MAIL DATED JANUARY 7, 2005, FOR WOLF CREEK GENERATING STATION (TAC NO. MC5407)

The Nuclear Regulatory Commission (NRC) has been reviewing the request by Wolf Creek Nuclear Operating Corporation (the licensee) to revise the withdrawal schedule for Capsules W and Z in the Reactor Vessel Material Surveillance Program for the Wolf Creek Generating Station. The capsules will be withdrawn in the Spring 2005 refueling outage in accordance with American Society for Testing and Materials (ASTM) E 185-82, "Standard Practice for Conducting Surveillance Tests for Light-Water Cooled Nuclear Power Reactor Vessels." In accordance with Section III.B.3 of Appendix H, "Reactor Vessel Material Surveillance Program Requirements," to 10 CFR Part 50, the proposed withdrawal schedule was submitted for approval. The application is dated December 16, 2004 (ET 04-0007).

In reviewing the application, I had three questions to clarify the information in the application, which were sent to the licensee by email. Attached is the e-mail dated January 7, 2005, from the licensee, with the three questions and the responses to the questions.

Docket No. 50-482

Enclosure:

E-mail Dated January 7, 2005

ML050120238 NRR-106 OFFICE PDIV-2/PM PDIV-2/LA PDIV-2/SC NAME JDonohew:sp EPeyton AWang for SDembek DATE 1/19/05 1/19/05 1/20/05 DOCUMENT NAME: E:\Filenet\ML050120238.wpd E-MAIL JANUARY 7, 2005 From: "Wideman Steven G" <stwidem@WCNOC.com>

To: "Jack Donohew" <JND@nrc.gov>

Date: 1/7/05 10:32AM

Subject:

RE: Questions on RV Surveillance Capsule Withdrawal Schedule Changes Jack - responses to your questions have been provided below as part of your original e-mail.

As I mentioned to you during the Wednesday telecon, this application was based on the information in the Farley plant Safety Evaluation associated with a change to their withdrawal schedule. I am attaching the Farley plant Safety Evaluation for you information and use as appropriate.

If you have any additional questions, please let me know.

Steve Wideman WCNOC Licensing 620-364-4037 The information contained in this electronic correspondence is informally submitted to the NRC and is not considered as docketed correspondence by Wolf Creek Nuclear Operating Corporation (WCNOC). Should the NRC wish to assign a docket number to this correspondence, WCNOC requests it be contacted to obtain concurrence.

---

Original Message-----

From: Jack Donohew [1]

Sent: Wednesday, January 05, 2005 11:04 AM To: Hooper Diane M; Wideman Steven G

Subject:

Questions on RV Surveillance Capsule Withdrawal ScheduleChanges Are the following questions addressed in the application dated December 16, 2004 (ET 04-0007):

1. How lead factors for Capsules U, V, X, and Y were calculated based on the dosimetry analysis for Capsule X.

RESPONSE: How the lead factors for Capsules U, V, X, and Y were calculated was not specifically addressed in the application other than a reference to WCAP-16028 submitted by WCNOC letter RA 03-0041 (Reference 4 in the application). The lead factors for the withdrawn Capsules U, Y, V, and X were calculated as the ratio of the neutron fluence received by the specimens in a specific surveillance capsule to the neutron fluence at the reactor pressure vessel inside surface at the peak fluence location. The measured fluence levels for these capsules are presented in Table 7-1 of Reference 4 and the calculated maximum pressure vessel fluences are presented in Table 6-2 (Page 6-17) of Reference 4. For instance, the measured fluence for Capsule U at the withdrawn EFPY of 1.07 is 3.16E+18 n/cm2 and the calculated peak fluence at the clad/base metal interface is 7.44E+17 n/cm2. Therefore, the lead factor for Capsule U is calculated to be 4.25 (i.e., 3.16E+18/7.44E+17).

2. Which of the three criteria in ASTM E 185-82, on plants with projected delta RTNDT and number of surveillance capsules withdrawn and evaluated, does the Wolf Creek Generating Station (WCGS) pressure vessel fall within, and the basis for the delta RTNDT for WCGS.

RESPONSE: In the application WCNOC did not specifically identify which of the three criteria in ASTM E 185-82 is applicable to WCGS. The WCGS reactor vessel falls within the first category plants because the RTndt shift is projected to be less than 100 deg F. Based on a chemistry factor (CF) of 39.1 deg F (calculated per Regulatory Guide 1.99, Rev 2, Position 2.1, see Table D-1 of Reference 4) and a fluence factor (FF) of 1.33 (determined from the equation FF=f(0.28-0.1xlog f) for a projected clad/base metal interface fluence of 3.51E+19 n/cm2 at the life extension of 54 EFPY), the limiting Delta-RTndt is calculated to be 52 deg F (i.e., FFxCF).

3. The expected effective full power years (EFPYs) of plant operation at the termination of license-renewal license.

RESPONSE: In Attachment I, fourth paragraph in the BACKGROUND section indicates the end of extended license life as 54 EFPY. At the end of extended license life (60-year), the plant operation would be approximately 54 EFPY. This is an estimate based on a projection of 34.6 EFPY at the end of the current license period (03/11/2025), plus an additional 19.5 EFPY projected for a 20-year license life extension.

<JND>

CC: "Hooper Diane M" <dihoope@WCNOC.com>, "Hseu Jin-shou N"

<jihseu@WCNOC.com>, "Anselmi Todd M" <toansel@WCNOC.com>, "Yokum Lorrie I"

<loyokum@WCNOC.com>