ML073241044

Summary of Conference Call Held on 10/25/2007, Between the U.S. Nuclear Regulatory Commission and Carolina Power & Light Company, Concerning Responses to Request for Additional Information Regarding Tube Inspection

ML073241044
Person / Time
Site:	Harris
Issue date:	11/15/2007
From:	Vaaler M NRC/NRR/ADRO/DORL/LPLII-2
To:
Vaaler, Marlayna, NRR/DORL 415-3178
References
RFO-13, TAC MD5385
Download: ML073241044 (3)

Text

November 15, 2007 NOTE TO: File FROM: Marlayna Vaaler, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 -

SUMMARY

OF CONFERENCE CALL HELD ON OCTOBER 25, 2007, BETWEEN THE U.S.

NUCLEAR REGULATORY COMMISSION AND CAROLINA POWER & LIGHT COMPANY, CONCERNING RESPONSES TO REQUESTS FOR ADDITIONAL INFORMATION PERTAINING TO THE REVIEW OF THE RFO-13 ONE YEAR STEAM GENERATOR TUBE INSPECTION REPORT (TAC NO. MD5385)

The U.S. Nuclear Regulatory Commission (NRC) and representatives of Carolina Power & Light Company, now doing business as Progress Energy Carolinas, Inc. (PGE), held a conference call on October 25, 2007, to discuss and clarify PGEs responses to the NRC staffs requests for additional information (RAIs) concerning the review of the steam generator (SG) tube inspection report from Refueling Outage 13 (RFO-13) for the Shearon Harris Nuclear Power Plant, Unit 1.

The conference call was useful in clarifying the RAI responses.

During the call, the following two topics were discussed:

1. The licensee's response to RAI 1 did not include a discussion of whether the loose parts were detected with the rotating coil and whether tube wear was detected with the rotating coil.

RAI 1 stated: On Page A1-2 of the letter dated April 20, 2007, you indicated that 10 tubes with loose part signals at the top of the tubesheet region on the hot-leg side of SG B were examined with a rotating coil. Please discuss the results of these rotating coil exams (i.e., were loose parts present, what were the loose parts, and were the loose parts removed), and discuss the results of any visual examinations in this area.

In addition, were all known foreign objects (other than the foreign object wedged between Tube Row 60 Column 45 (R60C45) and Tube R59C46 in SG A) in all three SGs removed? If not, please discuss what foreign objects were left inservice and the criteria used to determine which foreign objects are acceptable to leave inservice.

During the conference call, PGE confirmed that the loose parts signals were detected with the rotating coil as it is standard practice to inspect the periphery tubes (where the signals originated) and the SG blowdown lane with a rotating coil probe.

PGE also confirmed that no tube wear was detected with the rotating coil.

2. The NRC staff would like to obtain more information regarding the inspection sequence for the one tube in SG B with a slightly restricted area 22 inches up from the cold leg tube end. [RAI 4]

RAI 4 stated: Please discuss whether the signal of the one tube examined by rotating coil in a slightly restricted area of the tube within the tubesheet in SG B has changed since the baseline inspection. If so, please discuss the reason for the change. In addition, what was the nature of the signal?

During the conference call, PGE stated that they do not have a clear explanation for the restriction located approximately 22 inches up from the cold-leg tube end in SG B. The licensee provided the following inspection sequence for the affected tube:

(1) attempted to pass the bobbin probe from the hot-leg side (would not pass)

(2) attempted to pass the bobbin probe from the cold-leg side (would not pass)

(3) attempted to pass a +Point' probe from the cold-leg side (would pass).

The licensee indicated that it could be possible that something was moved; however the probe did not detect anything nearby. The licensee conducted a historical review and reported no degradation or restriction at this area. Based on the favorable results of their +Point' probe exam, they did not perform additional exams.

The licensee indicated that the +Point' probe detected no degradation, no bulge, or restriction.

PGE also stated that they had high confidence that there was no blockage in the SG tube, and that the restriction was most likely caused by a slight deformation that prevented the relatively inflexible bobbin coil from passing. The tube was left in service. The next planned SG tube eddy current inspection for the tube in question is scheduled for the Fall 2010 refueling outage.

The NRC technical staff was satisfied with these responses and stated that no further verifications were necessary for them to complete the review of the RFO-13 SG tube inspection report.

Docket No. 50-400

ML073241044 NRR-106 OFFICE LPL2-2/PM LPL2-2/LA LPL2-2/BC NAME MVaaler CSola TBoyce DATE 11/15/2007 N/A N/A