BVY 13-077, Supplemental Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Flooding Aspects of Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident
| ML13247A415 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee  |
| Issue date: | 08/30/2013 |
| From: | Wamser C Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| BVY 13-077 | |
| Download: ML13247A415 (7) | |
Text
Entergy Nuclear Operations, Inc.
Vermont Yankee 320 Governor Hunt Road Vernon, Vermont 05354 SPEntergy Tel :(802) 257-7711 Christopher J. Wamser Site Vice President BVY 13-077 August 30, 2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852
SUBJECT:
Supplemental Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Flooding Aspects of Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident Vermont Yankee Nuclear Power Station Docket No. 50-271 License No. DPR-28
REFERENCES:
- 1. NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated March 12, 2012
- 2. Entergy Nuclear Operations, Inc., Letter to NRC, Required Response 2 for NTTF Recommendation 2.1: Flooding - Hazard Reevaluation Report, BVY 13-021, dated March 12, 2013
Dear Sir or Madam:
On March 12, 2012, the NRC issued Reference 1 to all power reactor licensees and holders of construction permits in active or deferred status. Enclosure 2 of Reference 1 requested that each licensee perform a reevaluation of external flooding sources and report the results in accordance with the NRC's prioritization plan. Entergy Nuclear Operations, Inc. submitted the flood reevaluation for Vermont Yankee in Reference 2. Reference 2 contains interim actions that Vermont Yankee has taken to address higher flooding hazards relative to the design basis until the integrated assessment is completed.
The enclosed table provides a list of the interim actions taken as contained in Reference 2 along with additional supporting details and the dates they were implemented. Vermont Yankee will not modify any of these interim actions without first notifying our NRC Project Manager.
This letter contains one new regulatory commitment and reconfirms existing regulatory commitments. The new commitment is reflected in Attachment 2.
On August 27, 2013, Entergy announced that it had decided to permanently cease power operations of Vermont Yankee Nuclear Power Station in the fourth quarter 2014; this supplemental response was prepared prior to that decision. Entergy hereby notifies the NRC i~oci
BVY 13-077 / page 2 of 2 that the enclosed commitment will not be in effect upon docketing of the certifications for permanent cessation of operations and permanent removal of fuel from the reactor vessel required by 10CFR50.82.
Should you have any questions concerning the content of this letter, please contact Coley Chappell at (802)451-3374.
I declare under penalty of perjury that the foregoing is true and correct; executed on August 30, 2013.
Sincerely CJW / JTM Attachments: 1. Vermont Yankee Reevaluation Report Interim Action Commitments
- 2. List of Regulatory Commitments cc: William M. Dean USNRC Regional Administrator, Region 1 2100 Renaissance Blvd., Suite 100 King of Prussia, PA 19406-2713 U. S. Nuclear Regulatory Commission ATTN: Director, Office of Nuclear Reactor Regulation One White Flint North 11555 Rockville Pike Rockville, MD 20852-2378 NRC Senior Resident Inspector Vermont Yankee U. S. Nuclear Regulatory Commission ATTN: Richard Guzman Mail Stop: OWFN/08C2 11555 Rockville Pike Rockville, MD 20852-2378 U. S. Nuclear Regulatory Commission ATTN: Robert J. Fretz Jr.
Mail Stop: OWFN/4A15A 11555 Rockville Pike Rockville, MD 20852-2378 U. S. Nuclear Regulatory Commission ATTN: Robert L. Dennig Mail Stop: OWFN/10E1 11555 Rockville Pike Rockville, MD 20852-2378 Christopher Recchia, Commissioner VT Department of Public Service 112 State Street, Drawer 20 Montpelier, VT 05620-2601
ATTACHMENT 1 BVY 13-077 VERMONT YANKEE REEVALUATION REPORT INTERIM ACTION COMMITMENTS
BVY 13-077 / page 1 of 2 Attachment 1: Reevaluation Report Interim Action Commitments Item Interim Actions Taken or Planned to Take as Report Additional Actions Implementation Number Included in the Reevaluation Report Reference Date The LIP event is not included in the Vermont Yankee Current Licensing Basis (CLB). Although the maximum LIP flood level of El. 253.0' exceeds the CLB Probable Maximum Flood (PMF) still water elevation of El. 252.5', it is bounded by the exterior flood water height including wave run-up of El.
254.0'. Acknowledging the differences between the duration of the PMF and the LIP, as well as the available warning time, an Interim action to revise Procedure OPOP-PHEN-3127 "Natural Phenomena" Complete evaluation to determine the entry BVY 13-021 & to incorporate mitigative actions to protect the conditions for a probable Local Intense Switchgear Rooms from a Local intense 6/25/2013 Precipitation (LIP) event. Implement the 1 Section 5.1.6 Precipitation (LIP) event was planned with a guidance and actions in site procedures. completion date of July 1, 2013. OPOP-PHEN-3127, Revision 12, incorporating actions to protect the Switchgear Rooms from the effects of an LIP event that, with the exception of sandbagging the exterior doors, are identical to those actions to protect the rooms from the PMF was issued on 6/25/2013 Three Additional Actions were identified to support the changes to OPOP-PHEN-3127 as a result of the LIP event (refer to the Additional Actions below)
Determine the threshold precipitation event that could produce on-site flood levels above the El.
6.0 252.5 ft.
6/21/2013
- 1) Calculation VYC-3158, approved on 6/21/2013 determined that a threshold precipitation of 7 inches in a 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> period distributed per the guidance of NUREG/CR 7046 would result in a water
BVY 13-077/ page 2 of 2 Attachment 1: Reevaluation Report Interim Action Commitments surface elevation of greater than EL. 252.5 at those entrances that have been identified as pathways to the Switchgear Rooms and having the maximum resulting LIP elevations.
Data analyses by the Northeast Regional Climate Center indicate that the 500 year, 6-hour storm is approximately 6.4 inches, therefore the threshold precipitation of 7 inches in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is anticipated to have an occurrence interval of greater than 500 years.
Identify the type of storms that produce an LIP event.
Calculation VYC-3158, approved on 6/21/2013 6.0 documents that the storm that would be expected to produce a LIP event is a Mesoscale Convective 6/21/2013
- 2) System (MCS), likely to occur from June through September. Most often, this storm type over the VYNPS basin is not a strict MCS, but instead would include interaction with a front or remnant tropical moisture.
Determine the best method(s) to forecast an LIP event.
Calculation VYC-3158, approved on 6/21/2013 6.0 documents that the NOAA National Weather Service issues quantitative precipitation forecasts 6/21/2013
- 3) (QPF's) for periods of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to 5-days, which may be suitable for us in anticipating storms that may result in precipitation amounts in excess of the threshold value.
ATTACHMENT 2 BVY 13-077 LIST OF REGULATORY COMMITMENTS to BVY 13-077 Page 1 of 1 List of Regulatory Commitments The following table identifies those actions committed to by Entergy in this document. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.
TYPE (Check One) SCHEDULED COMMITMENT ONE- COMPLETION DATE ONE CONTINUING (If Required)
TIME ACTION COMPLIANCE Vermont Yankee will not modify any of the Prior to submitting the interim actions identified in Attachment 1 of Integrated Assessment this letter (BVY 13-077) without first notifying Report our NRC Project Manager.