ML090880003

Draft RAI from the Electrical Engineering Branch Re. the Proposed Extended Power Uprate Amendment for Monticello

ML090880003
Person / Time
Site:	Monticello
Issue date:	03/28/2009
From:	Tam P Plant Licensing Branch III
To:	Pointer K, Salamon G Northern States Power Co
Tam P
References
TAC MD9990
Download: ML090880003 (5)

Text

Accession No. ML090880003 From: Peter Tam Sent: Saturday, March 28, 2009 11:20 AM To: Peter Tam; 'Pointer, Kenneth'; 'Salamon, Gabor' Cc: Karl Feintuch; Matthew McConnell; Nitin Patel

Subject:

Monticello - Draft RAI from Electrical Engineering Branch re. proposed EPU amendment (TAC MD9990)

Ken:

Our review of your 11/5/09 application for an EPU amendment is ongoing. Our Electrical Engineering Branch has provided the following draft RAI questions. Please contact me to set up a conference call to discuss these questions. If you desire to hold the conference call during 3/24 - 4/10 when I am on leave, please contact my backup Karl Feintuch to make arrangements (301-415-3079).

All of the following questions are directly associated with Task Report T1004 that was provided in Enclosure 17, NSPM Response to Review Items Documents in the June 26, 2008 NRC Non-Acceptance Letter, of the EPU application:

1. In Section 3.4.2, the licensee provided an evaluation of D.G. OBrien and General Electric (GE) electrical penetrations. The staff requests the licensee to confirm that only D.G. OBrien and GE electrical penetrations are in its environmental qualification (EQ) program. If the licensee has other types of electrical penetrations in its EQ program, the staff requests the licensee to identify those penetrations and provide a discussion and details on how those penetrations are qualified for EPU conditions.

2. In Section 3.4.2, the licensee stated that the Limitorque actuator MO-2397 is qualified per DOR guidelines and by performing a thermal lag evaluation. The staff requests the licensee to confirm that the qualified temperature of Limitorque actuator MO-2397 (i.e.,

329 °F) adequately envelops the temperature assumed in the thermal lag evaluation.

3. In Section 3.4.3, the licensee identified several components that would be submerged due to EPU conditions. The licensee stated that these components are not credited for the postulated breaks and submergence level. The staff requests the licensee to confirm that failure of these components under a submerged condition would have no adverse impact on the safety functions of the associated components and systems.

4. In note 4 of Section 3.4.3, the licensee stated that the Rockbestos cables could be submerged and these cables are qualified for 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> in a submerged condition. The staff requests the licensee to provide the basis for the 18 hour2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> criteria for qualification, and also confirm that these cables are not submerged more than 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> and that these cables will perform their safety function during and post submergence.

5. In note 1 of Section 3.4.4, the licensee stated the ASCO pressure switches located in reactor building (RB) Volume 31 serve only as containment isolation valve position indication and are not required under a RB high-energy line break (HELB) event. The staff requests the licensee to confirm that the failure of these switches under EPU

conditions would not 1) adversely affect the safety function of the associated components or 2) mislead the operator.

6. In note 2 of Section 3.4.4:

a) The licensee stated that Barton Model 580 series pressure switches have no required safety function during a HELB in RB volume 18. The staff requests the licensee to confirm that failure of these switches under EPU conditions would not adversely affect the safety functions of the associated components and systems.

b) The licensee stated that additional testing from Barton on this switch model would easily demonstrate qualification for the temperature postulated under EPU conditions. The staff requests the licensee to confirm that this test is complete and that the switch is qualified for EPU conditions.

7. In note 3 of Section 3.4.4, the licensee stated that 1) the ITT Royal cable is only installed in local instrument panels in RB Volumes 14, 18, 19, 22, and 33 and that these cables are qualified for peak temperature of 211 °F, 2) the EPU HELB temperatures in RB volumes 14, 18, 19, 22, and 33 are 174.7 °F, 209.7 °F, 209.3 °F, 184 °F, and 211.7

°F, respectively, and 3) using engineering judgment that the HELB event would not exceed the test level of 211 °F as only a 0.7 °F difference between the test level and the predicted values exists. The staff requests the licensee to confirm that these cables are not exposed to any temperature rise or hot spots in the panels. If these cables are exposed to hot spots in the panels, then the staff requests the licensee to provide the qualification basis for these cables.

8. In Section 3.4.5, the licensee stated that the turbine building (TB) HELB review revealed that the Rockbestos Firewall III, Rockbestos EP, and Brand Rex cables are included in the EQ program. The licensee further stated that these cables are similar types to those already qualified for bounding conditions present in either the Drywell or the RB. The licensee concluded that these cables are qualified based on the fact that they are similar to the qualified cables. The staff requests the licensee to confirm that these cables are identical to the qualified cables or provide qualification basis for these cables in accordance with 10 CFR 50.49.

9. In Section 3.4.5, it is not clear to the staff that the equipment in TB volumes 7 and 8 are credited for EPU conditions. The staff requests the licensee to confirm that 1) the equipment in TB volumes 7 an 8 (which are considered harsh environments due to EPU conditions) are not required to mitigate accidents under EPU conditions and 2) the failure of the equipment in TB Volumes 7 and 8 would not adversely affect the safety functions of the associated components and systems.

10. In Section 3.4.5, the licensee stated that 1) there is a single Valcor solenoid valve in the EQ program located in TB Volume 21 and 2) this solenoid valve is same as the qualified solenoid valve in the redundant train located in the RB; and therefore, the solenoid valve in the TB remains qualified. The staff requests the licensee to confirm that 1) the solenoid valve in the TB has been maintained in accordance with the 10 CFR 50.49 program and 2) the qualification of the Valcor valve located in the RB envelops the qualification requirements of the solenoid valve located in TB volume 21.

11. In Section 3.4.7, table 3.4.7-1, for GE SIS cable (or any other manufacturer type SIS cable), the licensee is crediting 50% reduction in Beta radiation due to localized shielding. The licensee further stated that there is no increase in Drywell Beta radiation dose as a result of EPU. Based on this information, the staff requests the licensee to clarify why revising the analysis is necessary. Furthermore, the staff requests the licensee to provide details of localized shielding and confirm that these SIS cables are not used in open junction boxes. If these cables are used in open junction boxes, then the licensee should provide a detailed evaluation of beta radiation qualification.

12. Based on the staffs review of Section 3.4.5, it is not clear to staff that the licensee evaluated all equipment, other than cables, in TB Volume 13. The staff requests the licensee to confirm that all equipment was evaluated for EPU conditions in TB Volume 13.

13. The following questions relate to the ASCO pressure switch evaluation in attachment A2:

a) In note 2, the licensee stated that pressure switches PS-4666 and PS-4671 that are located in RB Volume 31 experience a peak HELB pressure of 17.19 psia.

The licensee further stated that these switches are only required to function for inside drywell events; and therefore, they are not required to be qualified for the HELB peak pressure in RB Volume 31. The staff requests the licensee to confirm that the failure of these switches during a HELB event will have no adverse impact on the safety functions of the associated components and systems.

b) The licensee stated that the pressure switches located in RB Volumes 1 and 3, and M style switches located in RB Volume 31 have short-term function durations and are bounded by the accident test. The staff requests the licensee to confirm that the failure of these switches during the entire accident event will have no adverse impact on the safety functions of the associated components and systems.

c) The licensee stated the following:

As a result of accepting twice the thermal aging for the Viton as represented by the 30 day exposure at 210 °F for specimen # 3, the limiting life component has changed from the Viton to either M or non M style internal switch for all ASCO pressure switches.

The staff does not understand the intent of this discussion. The staff requests the licensee to provide a detailed explanation of the above statement.

d) Based on our review of the licensees ASCO pressure switch evaluation, the staff understands that the licensee has used thermal aging to qualify for the loss-of-coolant accident (LOCA) and/or Post-LOCA conditions. The staff requests the licensee to provide a detailed explanation and justification for using this methodology for qualifying these switches.

14. Based on our review of the GE Cable qualification evaluation that was provided in attachment A4, the staff understands that the licensee has used thermal aging to qualify

for the LOCA and/or Post-LOCA conditions. The staff requests the licensee to provide a detailed explanation and justification for using this methodology for qualifying these cables.

15. Base on our review of attachment A17, the staff requests the licensee to provide the following information:

a) The qualification of the ITT Royal PVC cable pre-EPU conditions.

b) The results of the test on naturally aged 20 year-old ITT Royal PVC cable.

c) Demonstrate the qualification of ITT Royal PVC cables for the environmental conditions (such as radiation, humidity, and pressure) where these cables are installed.

This e-mail aims solely to prepare you and others for the requested conference call. This e-mail does not convey a formal NRC staff position, and does not formally request for additional information.

Peter S. Tam, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Tel. 301-415-1451 E-mail Properties Mail Envelope Properties (C56E360E9D804F4B95BC673F886381E71DBF72EB93)

Subject:

Monticello - Draft RAI from Electrical Engineering Branch re. proposed EPU amendment (TAC MD9990)

Sent Date: 3/28/2009 11:20:16 AM Received Date: 3/28/2009 11:20:00 AM From: Peter Tam Created By: Peter.Tam@nrc.gov Recipients:

Peter.Tam@nrc.gov (Peter Tam)

Tracking Status: None Kenneth.Pointer@xenuclear.com ('Pointer, Kenneth')

Tracking Status: None Gabor.Salamon@xenuclear.com ('Salamon, Gabor')

Tracking Status: None Karl.Feintuch@nrc.gov (Karl Feintuch)

Tracking Status: None

Matthew.McConnell@nrc.gov (Matthew McConnell)

Tracking Status: None Nitin.Patel@nrc.gov (Nitin Patel)

Tracking Status: None Post Office:

HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 25530 3/28/2009 Options Expiration Date:

Priority: olImportanceNormal ReplyRequested: False Return Notification: False Sensitivity: olNormal Recipients received: