ML101720643
| ML101720643 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/16/2010 |
| From: | Clark R Entergy Operations |
| To: | Kalyanam N Plant Licensing Branch IV |
| Kalyanam N, NRR/DLPM, 415-1480 | |
| References | |
| TAC ME3399 | |
| Download: ML101720643 (2) | |
Text
From:
CLARK, ROBERT W [RCLARK@entergy.com]
Sent:
Wednesday, June 16, 2010 2:36 PM To:
Kalyanam, Kaly Cc:
BICE, DAVID B
Subject:
RE: Arkansas Nuclear One Unit 2 SG report from 2R20 Kaly, you sent me a set of questions or requests for clarifications on June 10 concerning the ANO-2 SG report. Below are the responses to those requests. This information has been peer reviewed prior to this email. It is my understanding that the transmission of this information via email is acceptable and you do not need us to issue you a formal letter. If that has changed please let me know.
Bob After review of the Arkansas Nuclear One Unit 2 SG report from their 2009 refueling outage, Ken and I had some clarifying questions we would like to ask the licensee. Because they are just clarifications, we dont feel the need to use the formal RAI process. Please forward the questions listed below to the licensee and let them know they can respond either by email or via a phone call.
- 1. In Section 3.4 of the SG tubing report, the licensee states that mechanical wear at anti-vibration bars and tube support plates, previous loose part wear, and fabrication induced indications were the only identified degradation mechanisms. Table 3.4.1 lists a wear indication in the tube at Row 142 Column 111, in SG A, that appears to be a loose part wear indication that has not been previously reported (i.e., it does not appear in the inspection report from outage 2R17). Please clarify the history and nature of this indication.
This is correct - in 2R17 (previous outage) a part was identified in this area but the tube of reference was clean (R142C111). However, this particular tube only had top of tubesheet testing with the Plus Point and not a full length bobbin. The scope of the inspection was a 50% bobbin examination for the initial examination. The part was a long weld wire from fabrication that was lodged in the tubes. The part was removed after eddy current. It is possible that the tube R142C111 was damaged during removal of the part and left the wear scar on the tube. A picture of the part is listed below with the other affected tubes.
- 2. Please clarify the scope and results of any secondary side inspections.
The secondary side inspection was limited to the annulus area of both generators to look for loose parts. One additional part was removed from the center lane but had no impact on the adjacent tubes.
- 3. The staff notes that in Table 3.6, the % Plugged columns are reporting the fraction of tubes plugged and not the percentage of tubes plugged (e.g., 0.0003 vice 0.03).
You are correct. The actual numbers of tubes plugged are 5 in SGA and 13 in SGB. The total population of tubes is 10637 tubes total so percentages are:
SGA SGB 5/10637 = 0.00047 or 0.05% 13/10637 = 0.0012 or 0.12%
From: Kalyanam, Kaly [1]
Sent: Thursday, June 10, 2010 1:08 PM To: CLARK, ROBERT W
Subject:
FW: Arkansas Nuclear One Unit 2 SG report from 2R20 Importance: High
- Bob, The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again.
Please use this email in place of the first one. This has 3 questions!
Thanks Kaly From: Johnson, Andrew Sent: Thursday, June 10, 2010 2:06 PM To: Kalyanam, Kaly Cc: Karwoski, Kenneth
Subject:
Arkansas Nuclear One Unit 2 SG report from 2R20 Importance: High
- Kaly, Forgot one question in the first emailrevised email below.
After review of the Arkansas Nuclear One Unit 2 SG report from their 2009 refueling outage, Ken and I had some clarifying questions we would like to ask the licensee. Because they are just clarifications, we dont feel the need to use the formal RAI process. Please forward the questions listed below to the licensee and let them know they can respond either by email or via a phone call.
- 4. In Section 3.4 of the SG tubing report, the licensee states that mechanical wear at anti-vibration bars and tube support plates, previous loose part wear, and fabrication induced indications were the only identified degradation mechanisms. Table 3.4.1 lists a wear indication in the tube at Row 142 Column 111, in SG A, that appears to be a loose part wear indication that has not been previously reported (i.e., it does not appear in the inspection report from outage 2R17). Please clarify the history and nature of this indication.
- 5. Please clarify the scope and results of any secondary side inspections.
- 6. The staff notes that in Table 3.6, the % Plugged columns are reporting the fraction of tubes plugged and not the percentage of tubes plugged (e.g., 0.0003 vice 0.03).
- regards, Andrew Johnson Materials Engineer NRR/DCI/CSGB U.S. Nuclear Regulatory Commission 301-415-1475 E-mail Properties
Mail Envelope Properties (2484AD580AAA9349BAEC5333CA9B357B07B9E98B)
Subject:
RE: Arkansas Nuclear One Unit 2 SG report from 2R20 Sent Date: 6/16/2010 2:36:27 PM Received Date: 6/16/2010 2:36:27 PM From: CLARK, ROBERT W Created By: RCLARK@entergy.com Recipients:
Kaly.Kalyanam@nrc.gov (Kalyanam, Kaly)
Tracking Status: None DBICE@entergy.com (BICE, DAVID B)
Tracking Status: None Post Office:
LITEXETSP002.etrsouth.corp.entergy.com Files Size Date & Time MESSAGE 83963 6/16/2010 image001.gif 59274 Options Expiration Date:
Priority: olImportanceNormal ReplyRequested: False Return Notification: False Sensitivity: olNormal Recipients received: