ML14035A223
| ML14035A223 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 01/29/2014 |
| From: | Wamser C J Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| BL-12-001, BVY 14-007 | |
| Download: ML14035A223 (5) | |
Text
SNEntergy Entergy Nuclear Operations, Inc.Vermont Yankee320 Governor Hunt Rd.Vernon, VT 05354(802) 257-7711Christopher J. WamserSite Vice President BVY 14-007January 29, 2014U.S. Nuclear Regulatory Commission Attn: Document Control DeskWashington, DC 20555-0001
SUBJECT:
REFERENCES:
Response to Request for Additional Information Regarding Response toBulletin 2012-01, "Design Vulnerability in Electric Power System"Vermont Yankee Nuclear Power StationDocket No. 50-271License No. DPR-281. Letter, NRC to Entergy Nuclear Operations, Inc. "DesignVulnerability in Electric Power System,"
dated July 27, 20122. Letter, Entergy Nuclear Operations, Inc. to NRC, "90 DayResponse to Bulletin 2012-01,
'Design Vulnerability in ElectricPower System',"
BVY 12-074, dated October 25, 20123. Letter, NRC to Entergy Nuclear Operations, Inc. "Request forAdditional Information Regarding Response to Bulletin 2012-01,'Design Vulnerability in Electric Power System',"
dated December20, 20134. Letter, Entergy Nuclear Operations, Inc. to NRC, "Notification ofPermanent Cessation of Power Operations,"
BVY 13-079, datedSeptember 23, 2013
Dear Sir or Madam:
In Reference 1, the NRC issued Bulletin 2012-01, requesting that each licensee submit awritten response in accordance with 10 CFR 50.54(f) within 90 days of the bulletin to providethe requested information.
Reference 2 provided the 90 day response for Vermont YankeeNuclear Power Station.
In Reference 3, the NRC requested additional information to verifycompletion of interim corrective actions and compensatory measures and to determine thestatus of each licensee's long-term corrective actions.
Attachment 1 of this letter provides therequested information for VY.There are no new regulatory commitments being made in this submittal.
Should you have any questions concerning this letter or require additional information, pleasecontact Mr. Coley Chappell at (802) 451-3374.
BVY 14-007 / Page 2 of 2I declare under the penalty of perjury that the foregoing is true and correct.Executed on January 29, 2014.Sincerely,
[CJW/JTM]
Attachments:
- 1.Bulletin 2012-01 Response to Request for Additional Information cc: Mr. William M. DeanRegional Administrator, Region 1U.S. Nuclear Regulatory Commission 2100 Renaissance Blvd, Suite 100King of Prussia, PA 19406-2713 Mr. Douglas V. Pickett, Project ManagerDivision of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop OWFN-8-G9A Washington, DC 20555USNRC Resident Inspector Vermont YankeeMr. Christopher
- Recchia, Commissioner Vermont Department of Public Service112 State Street -Drawer 20Montpelier, Vermont 05620-2601 BVY 14-007Docket 50-271Attachment 1Vermont Yankee Nuclear Power StationBulletin 2012-01 Response to Request for Additional Information BVY 14-007 / Attachment 1 / Page 1 of 2RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FORBULLETIN 2012-01.
"DESIGN VULNERABILITY IN ELECTRIC POWER SYSTEM"VERMONT YANKEE NUCLEAR POWER STATIONENTERGY NUCLEAR OPERATIONS.
INCDOCKET NO. 50-271On July 27, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued Bulletin 2012-01, "Design Vulnerability in Electric Power System" (Agencywide Documents Access andManagement System Accession No. ML 12074A1 15), to all holders of operating licensesand combined licenses for nuclear power reactors.
In addition, Watts Bar Nuclear Plant,Unit 2, is addressing the issues identified in the bulletin as part of the licensing process.Bulletin 2012-01 requested information about each facility's electric power systemdesigns, in light of recent operating experience involving the loss of one of the threephases of the offsite power circuit (single-phase open circuit condition) at Byron Station,Unit 2.In order for the NRC staff to complete its review of responses to the bulletin, thefollowing additional information is requested:
- 1. Provide a summary of all interim corrective actions that have been taken since theJanuary 30, 2012, event at Byron Station, Unit 2, to ensure that plant operators canpromptly diagnose and respond to open phase conditions on the offsite powercircuits for Class-i E vital buses until permanent corrective actions are completed.
Response
As described in Vermont Yankee's (VY) original response to Bulletin 2012-001 (Reference 2),VY has implemented the following interim corrective actions:* Heightened surveillances were originally initiated to detect an open phase fault.These include a once per shift visual check of the overhead conductors associated with the offsite power source and enhanced once per shift controlroom meter readings to check for balanced voltage and currents on lines andbuses associated with the offsite power circuits.
- Night orders were originally issued to make operators aware of symptomsassociated with open phase conditions.
- The heightened surveillances and night orders have been converted topermanent changes to operator rounds and permanent changes to existingstation operating procedure OPON-3150-01, "Loss of Start Up Transformer(s)."
- VY has revised its operator training programs for initial and requalification training to include the Byron event, its consequences and the required interimoperator responses.
- VY has reviewed the configuration of the overhead lines associated with theoffsite power circuits.
VY has concluded, based on the configuration of its linesand insulators (predominantly Lapp suspension insulators),
that it is lesssusceptible to the same failures which occurred at Byron Station.* VY has initiated a replacement program for the insulators in the 345 kVswitchyard as a corrective action from a past insulator failure.
BVY 14-007 / Attachment 1 / Page 2 of 22. Provide a status and schedule for completion of plant design changes andmodifications to resolve issues with an open phase of electric power.Response:
Because of the complexity of this issue and the need to develop a secure and reliable means todetect the open phase condition and to automatically protect electric equipment from potential damage caused by the open phase condition, the industry proposed to the NRC staff the needto carefully develop and design a protection system to detect open phase faults. The nuclearindustry proposed the following schedule:
By December 31, 2014: Complete all analysis of the open phase condition usingindustry criteria and identify appropriate actions (design changes, if necessary) requiredto demonstrate compliance.
By December 31, 2016: Implement design changes, if necessary, to comply with theopen phase condition criteria.
The "active" actuation features of new technology may beinstalled in a monitoring mode, with adequate justification, for security reasons.Bulletin 2012-01 was addressed to all holders of operating licenses and combined licenses fornuclear power reactors, except those who have permanently ceased operation and havecertified that fuel has been removed from the reactor vessel.On September 23, 2013, Entergy Nuclear Operations, Inc. notified the NRC (Reference
- 4) thatit intended to permanently cease power operations of VY at the end of the current operating cycle, which is expected to occur in the fourth quarter of 2014.Once VY has permanently ceased operations, permanently defueled and submitted thecertifications required by 10 CFR 50.82(a)(1
)(i) and (ii), the issues identified by the Bulletin willno longer be applicable to VY. VY is currently preparing plans to decommission the site whileconcurrently safely completing the current operating cycle. Resources which otherwise wouldhave been assigned to refueling outage preparation are now assigned decommissioning preparation activities.
Allocation of resources to study, plan, design, and purchase materials which will never be installed does not maintain or enhance protection of the public health andsafety.The actions to address the open circuit conditions are scheduled for completion well after VYshall cease power operations; therefore VY is not planning to complete the open circuitcondition analyses or to develop modification packages to address the open phase condition.
Based on this, VY plans to continue to implement and maintain the interim measures taken inresponse to the Bulletin until the fuel has been certified to be permanently removed from thereactor vessel following permanent cessation of operation at the end of the current operating cycle.