ML14115A444
| ML14115A444 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 04/25/2014 |
| From: | Siva Lingam Plant Licensing Branch II |
| To: | Murray W Duke Energy Corp |
| References | |
| ME9309, ME9310 | |
| Download: ML14115A444 (3) | |
Text
1 NRR-PMDAPEm Resource From:
Lingam, Siva Sent:
Friday, April 25, 2014 7:57 AM To:
Murray, William R. (Bill) (Bill.Murray@duke-energy.com)
Cc:
Quichocho, Jessie; Regner, Lisa; Hon, Andrew; Mathew, Roy; Zimmerman, Jacob
Subject:
Brunswick 1 and 2 - Bulletin (BL) 2012-01 Request for Additional Information (RAI)
Response Follow-up RAI (TAC Nos. ME9309 and ME9310)
Please note the following official RAI associated with BL 2012-01 for Brunswick 1 and 2, and provide your response within 30 days from the date of this e-mail.
Duke Energy Progress, Inc. (the licensee) response to NRC staffs Request for Additional Information (RAI) regarding response to Nuclear Regulatory Commission (NRC)Bulletin 2012-01, Design Vulnerability in Electric Power System, dated January31, 2014, in response to interim corrective action taken to ensure that plant operators can promptly diagnose and respond to open phase conditions on the offsite power circuits for Class-1 E vital buses until permanent corrective actions are completed, stated the following:
During Operating Modes 4 and 5, daily walk-downs were performed in the Transformer Yard and Switchyard (e.g., refueling outage March 2013, and maintenance outage May 2013) to identify any open phase conditions (i.e., broken 230kV connections). The walkdowns continue to be procedurally required during Operating Modes 4 and 5. During walk downs, Operations personnel look for any anomalies or out of normal conditions and take appropriate actions.
During Operating Modes 4 and 5, phase-to-phase voltage readings were obtained daily, and are evaluated for acceptability. The voltage readings continue to be procedurally required during Operating Modes 4 and 5.
Operating instructions and training curriculum were reviewed to ensure operators can diagnose and respond to an open phase condition.
Annunciator procedures for each 4kV motor were revised to include an open phase condition as a possible cause for a motor trip.
Operations procedures were revised to include recognition of equipment problems caused by an open phase condition, and appropriate responses.
Annual infrared (i.e., thermography) inspections of yard equipment have been performed and are ongoing.
The NRC staff notes that the licensees response dated October 24, 2012, states that the installed relays were not designed to detect single-phase open circuit conditions. Please explain why taking the above actions in Mode 4 and 5 will ensure that plant operators can promptly diagnose and respond to open phase conditions on the credited offsite power circuits for Class-1 E vital buses. Also, please explain the specific interim actions that are implemented during Mode 1, 2, and 3 when the onsite and offsite power systems are required to be operable in accordance with plant Technical Specification 3.8.1 to address the open phase design vulnerability.
Siva P. Lingam U.S. Nuclear Regulatory Commission Project Manager (NRR/DORL/LPL2-2)
Brunswick Steam Electric Plant Robinson Steam Electric Plant Location: O8-D5; Mail Stop: O8-G9a
2 Telephone: 301-415-1564; Fax: 301-415-1222 E-mail address: siva.lingam@nrc.gov
Hearing Identifier:
NRR_PMDA Email Number:
1245 Mail Envelope Properties (Siva.Lingam@nrc.gov20140425075700)
Subject:
Brunswick 1 and 2 - Bulletin (BL) 2012-01 Request for Additional Information (RAI) Response Follow-up RAI (TAC Nos. ME9309 and ME9310)
Sent Date:
4/25/2014 7:57:17 AM Received Date:
4/25/2014 7:57:00 AM From:
Lingam, Siva Created By:
Siva.Lingam@nrc.gov Recipients:
"Quichocho, Jessie" <Jessie.Quichocho@nrc.gov>
Tracking Status: None "Regner, Lisa" <Lisa.Regner@nrc.gov>
Tracking Status: None "Hon, Andrew" <Andrew.Hon@nrc.gov>
Tracking Status: None "Mathew, Roy" <Roy.Mathew@nrc.gov>
Tracking Status: None "Zimmerman, Jacob" <Jacob.Zimmerman@nrc.gov>
Tracking Status: None "Murray, William R. (Bill) (Bill.Murray@duke-energy.com)" <Bill.Murray@duke-energy.com>
Tracking Status: None Post Office:
Files Size Date & Time MESSAGE 2963 4/25/2014 7:57:00 AM Options Priority:
Standard Return Notification:
No Reply Requested:
No Sensitivity:
Normal Expiration Date:
Recipients Received: