ML020910482

Request for Additional Information (Rai), Millstone Nuclear Power Station, Unit NO.2, Following Receipt of the Licensee'S Supplemental Submittal Dated March 13, 2002

ML020910482
Person / Time
Site:	Seabrook
Issue date:	04/01/2002
From:	Richard Ennis NRC/NRR/DLPM/LPD1
To:	Clifford J NRC/NRR/DLPM/LPD1
Starkey D
References
TAC MB4223
Download: ML020910482 (3)

Text

April 1, 2002 MEMORANDUM TO: James W. Clifford, Chief, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation FROM: Richard B. Ennis, Project Manager, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION (RAI), MILLSTONE NUCLEAR POWER STATION, UNIT NO. 2, FOLLOWING RECEIPT OF THE LICENSEES SUPPLEMENTAL SUBMITTAL DATED MARCH 13, 2002 (TAC NO. MB4223)

The attached RAI was faxed on March 15, 2002, to Mr. Ravi Joshi of Dominion Nuclear Connecticut, Inc. (the licensee). The RAI was faxed to facilitate the technical review being conducted by NRR concerning the licensees request to use an alternative to ASME code Section XI repair welding requirements. Subsequent to the fax transmission, the RAI was discussed with the licensee during a phone call on March 18, 2002, during which the licensee agreed to respond in writing to the RAI. During the conference call, it was noted that the questions were not numbered in sequential order. The RAI questions were numbered 1, 2, 4.....8. There was not a question numbered three. Although the RAI questions were numbered out of sequence, the RAI contained the total number of intended questions, which was seven. The licensee will note in their written response to the RAI that question number three was intentionally left blank. Also, in questions numbered four and five, all references to IWA-3600 should have referenced IWB-3600 instead. This memorandum and the attachment do not convey or represent an NRC staff position regarding the licensees request.

Docket No. 50-443

Attachment:

Follow Up NDE Questions on Millstone response to NRCs Request for Additional Information Submittal dated March 13, 2002

April 1, 2002 MEMORANDUM TO: James W. Clifford, Chief, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation FROM: Richard B. Ennis, Project Manager, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION (RAI), MILLSTONE NUCLEAR POWER STATION, UNIT NO. 2, FOLLOWING RECEIPT OF THE LICENSEES SUPPLEMENTAL SUBMITTAL DATED MARCH 13, 2002 (TAC NO. MB4223)

The attached RAI was faxed on March 15, 2002, to Mr. Ravi Joshi of Dominion Nuclear Connecticut, Inc. (the licensee). The RAI was faxed to facilitate the technical review being conducted by NRR concerning the licensees request to use an alternative to ASME code Section XI repair welding requirements. Subsequent to the fax transmission, the RAI was discussed with the licensee during a phone call on March 18, 2002, during which the licensee agreed to respond in writing to the RAI. During the conference call, it was noted that the questions were not numbered in sequential order. The RAI questions were numbered 1, 2, 4.....8. There was not a question numbered three. Although the RAI questions were numbered out of sequence, the RAI contained the total number of intended questions, which was seven. The licensee will note in their written response to the RAI that question number three was intentionally left blank. Also, in questions numbered four and five, all references to IWA-3600 should have referenced IWB-3600 instead. This memorandum and the attachment do not convey or represent an NRC staff position regarding the licensees request.

Docket No. 50-443

Attachment:

Follow Up NDE Questions on Millstone response to NRCs Request for Additional Information Submittal dated March 13, 2002 DISTRIBUTION PUBLIC R. Ennis PD1-2 Reading J. Clifford D. Naujock ACCESSION No. ML020910482 OFFICE PDI-2/PM NAME REnnis DATE 4/1/2002 OFFICIAL RECORD COPY

Follow Up NDE Questions on Millstone 2 response to NRCs Request for Additional Information Submittal dated March 13, 2002

1. NB-4622.11 states Whenever PWHT is impractical or impossible, limited weld repairs to dissimilar metal welds... may be made without PWHT...

Question 1. The licensee needs to discuss the impracticality or impossibility of meeting this Code requirement. For example, if radiation exposure is the reason for impracticality or impossibility, the licensee should provide a discussion that quantitatively describes the radiation exposure differences between a Code required repair and the proposed alternative. (Note:

Other plants, including both Oconee-2 and TMI-1 have performed repairs using the Framatome process on their CRDMs with PWHT).

2. NB-4622.11(c)(6) discusses specific electrode diameters and crown removal for specific layers. Identify the electrode diameter and explain why the weld crown is not significant to this process. Include any technical data that correlates weld layer thickness (and other essential variables) with an acceptable tempered microstructure.

4. Attachment 2/Page 3 states that selected portions of the 1992 Edition of Section XI will be used in place of the 1989 Edition of Section XI. Attachment 2/Page 7 identifies IWA-4700 and /Page 14 identifies IWA-3600 as using the 1992 Edition of Section XI, hence in need of relief. However, the section on the Code requirements for which relief is requested does not address IWA-3600. A discussion relative to IWA-3600 needs to be provided.

5. Attachment 2/Page 14 and 23 state that there is a potential for a crack to occur at the triple point and that this crack will be evaluated according to IWA-3600. From the description in the submittal, this defect is not well understood and is indeterminate. In the absence of additional technical information on this condition, the staff is unable to determine the safety significance of this defect. Therefore, this item in the submittal will not be evaluated. In the event that cracking is identified at the triple point, a separated request for relief for NB-5330(b) will have to be submitted. The staff will not approve relief from this code requirement before the condition is shown to have occurred.

6. Attachment 2/Page 23 states the phrase to the maximum practical extent. This phrase lacks specificity. Identify the total volume percent (defined by your submittal) of Figures 4a through 4e that will be examined (i.e. what percent of the base metal HAZ will not be examined)

7. Attachment 2/Page15 presents a discussion on the corrosion of the carbon steel base metal.

Discuss the effects that the findings of the cavity in the RPV head at Davis Besse will affect your discussion. Explain why cracks left exposed to the primary water environment will not create a similar condition like Davis Besses RPV head.

8. Attachment 3/Page 3 is requesting relief from IWB-3142.4 pertaining to the successive examinations of the triple point anomaly. The staff considers this as an extension of question 5, and therefore, will not be approved prospective of the need.

Attachment