ML062330074
| ML062330074 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 08/15/2006 |
| From: | Thadani M Office of Nuclear Reactor Regulation |
| To: | Madden F TXU Electric |
| References | |
| TAC MC6952 | |
| Download: ML062330074 (3) | |
Text
- ohan Thadani - Fred/Denny:
Page 1 From:
Mohan Thadani To:
fnternet:dbuschbl @txu.com; Internet:fred.madden@ txu.com Date:
08/15/2006 1:30:22 PM
Subject:
Fred/Denny:
Fred/Denny:
The Nuclear Regulatory Commission (NRC) staff has reviewed the information in your letter dated February 14, 2006 (ADAMS Accession No. ML060540491), submitted for the NRC staff review of the steam generator tube inservice inspection twelve month report for Comanche Peak Unit 2 inspections performed during the spring of 2005 refueling outage (2RF08). The NRC staff has determined that additional information is required in order for the N'RC staff to complete its evaluation of your request. Our preliminary request for additional information is presented below. Please advise an approximate date by which CPSES would respond to the request. If CPSES would require a formal RAI request, the NRC staff will promptly provide it.
Thank you for your cooperation.
Mohan (301) 415-1476 PRELIMINARY REQUEST FOR ADDITIONAL INFORMATION 2RF08 STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT COMANCHE PEAK UNIT 2
TAC NO. MC6952 DOCKET NO. 50-446
- 1.
Were all foreign objects identified by The Foreign Object Search and Retrieval Program or by eddy current inspections removed from the steam generators? If not, discuss what analyses were performed to ensure these potential loose parts do not compromise tube integrity for the period of time between inspections.
- 2.
Of the eight tubes plugged during the 2RF08 outage due to the presence of single volumetric indication (SVI), two of the tubes (SG2-16-79 arid SG4-27-74) displayed SVIs within in the freespan region between two hot-leg tube support plates. The remaining six tubes (SG1 111, SG3-6-33, SG3-7-33, SG3-48-40, SG3-48-41, and SG4-24-89) displayed SVIs at the support structure intersections (C1, C6, C2 and H8). What is the cause of each of these indications, including the two freespan indications? If any of the indications are loose parts related, were the subject loose parts visually identified and retrieved? If not, were the subject tubes stabilized? Also, please clarify whether tube SG3-R6-C80, which was plugged during 2RF06, has been stabilized.
- 3.
During the 2RF08 outage, one tube (SG1-4-109) with an indication denoted as "RRT" was plugged according to the table in the February 14, 2006, report. Please discuss the cause of this restriction. Was there any change in the degree of restriction compared to earlier inspections, and if so, what is the cause of the change?
- 4.
Please confirm the absence of crack-like indications during the 2RF08 tube inspections.
ohan Thadani - Fred/Denny:
Page 2]
- 5.
Degradation of the waterbox cap plate region has been reported at the Byron 2 Model DT steam generators (
Reference:
ADAMS Accession No. ML042260202). What actions have been taken to address the potential for similar problems at Comanche Peak 2?
CC:
Murphy, Emmett
\\temp\\GW}Ooo01.TMP Mail Envelope Properties (44E204AE.DC7 : 23: 35106)
Page 17
(~~Vt UCJLT?&&W4
Subject:
Creation Date From:
Created By:
Fred/Denny:
08/15/2006 1:30:22 PM Mohan Thadani MCT@nrc.eov Recipients fred PM madden (Internet:fred.madden @txu.com)
Action Transferred Date & Time 08/15/2006 1:30:40 nrc.gov TWGWPOO1I.HQGWDO01 PM ELM CC (Emmett Murphy)
Delivered 08/15/2006 1:30:30 txu.com PM dbuschbl (Internet:dbuschbl @txu.com)
Transferred 08/15/2006 1:30:40 Post Office fred TWGWPOOI.HQGWDOO1 Delivered Route Internet:txu.com 08/15/2006 1:30:30 PM nrc.gov txu.com Files MESSAGE Options Auto Delete:
Expiration Date:
Notify Recipients:
Priority:
ReplyRequested:
Return Notification:
Concealed
Subject:
Security:
To Be Delivered:
Status Tracking:
Size 4618 Date & Time 08/15/2006 1:30:22 PM No None Yes Standard No None No Standard Immediate Delivered & Opened