ML20134F945

Forwards Safety Evaluation Accepting TR YAEC-1926 & Incorporation of Power/Flow Exclusion Region Calculation Method Using LAPUR5 Computer Code & Implementation of Solomon Stability Monitor for Licensee Facility

ML20134F945
Person / Time
Site:	Vermont Yankee
Issue date:	11/05/1996
From:	Craig Harbuck NRC (Affiliation Not Assigned)
To:	Reid D VERMONT YANKEE NUCLEAR POWER CORP.
Shared Package
ML20134D196	List: ML20134D193 ML20134F945 ML20134F963
References
TAC-M94207, NUDOCS 9611080207
Download: ML20134F945 (3)

Text

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'd

'Mr. Donald A. Reid November 5, 1996 Vice President, Operations  !

Vermont Yankee Nuclear Power Corporation

' Ferry Road Brattleboro, VT 05301 l

SUBJECT:

SAFETY EVALUATION OF THE POWER / FLOW EXCLUSION REGION CALCULATION l METHOD USING THE LAPUR5 COMPUTER CODE AND IMPLEMENTATION OF THE SOLOMON STABILITY MONITOR FOR VERMONT YANKEE NUCLEAR POWER STATION (TAC NO. M94207)

Dear Mr. Reid:

By letter dated October 31, 1995, as supplemented on November 3, 1995, Vermont Yankee Nuclear Power Corporation submitted a validation report, YAEC-1926,

" Method for Power / Flow Exclusion Region Calculation Using the LAPUR5 Computer

, Code," which is Yankee Atomic Electric Company's application of Boiling Water l Reactor Owners Group (BWROG) stability exclusion region methodology for j implementation of long-term solution Option 1-D at Vermont Yankee Nuclear

! Power Station (VYNPS). As discussed in the enclosed safety evaluation (SE), l l the NRC staff finds that (1) the proposed method for power / flow exclusion

! region calculation using the LAPURS computer code, and (2) the VYNPS implementation of the SOLOMON stability monitor are acceptable. The NRC l

staff's SE is based, in part, on the attached technical evaluation report ,

(TER) by Oak Ridge National Laboratory.

Prior to incorporating a power / flow exclusion region calculated by this methodology into the plant Core Operating Limits Report, this approved methodology should be referenced in the plant Technical Specifications.

i Sincerely, ORIGINAL SIGNED BY:  !

C. Craig Harbuck, Acting Senior Project Manager

Project Directorate I-1 l Division of Reactor Projects - I/II  ;

Office of Nuclear Reactor Regulation '

Docket No. 50-271 l

Enclosure:

Safety Evaluation w/ attached TER )

cc: See next page j DISTRIBUT10H:

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DOCUMENT NAME: G:\ VERMONT \VY94207.LTR 4

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NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20066-0001 l

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% ,4 Noveraber 5,1996 Mr. Donald A. Reid l Vice President, Operations Vermont Yankee Nuclear Power Corporation l Ferry Road l Brattleboro, VT 05301

! l

SUBJECT:

SAFETY EVALUATION OF THE POWER / FLOW EXCLUSION REGION CALCULATION l METHOD USING THE LAPURS COMPUTER CODE AND IMPLEMENTATION OF THE SOLOMON STABILITY MONITOR FOR VERMONT YANKEE NUCLEAR POWER STATION (TAC N0. M94207) l l

Dear Mr. Reid:

By letter dated October 31, 1995, as supplemented on November 3, 1995, Vermont Yankee Nuclear Power Corporation submitted a validation report, YAEC-1926, j

" Method for Power / Flow Exclusion Region Calculation Using the LAPUR5 Computer Code," which is Yankee Atomic Electric Company's application of Boiling Water Reactor Owners Group (BWROG) stability exclusion region methodology for implementation of long-term solution Option 1-D at Vermont Yankee Nuclear ,

Power Station (VYNPS). As discussed in the enclosed safety evaluation (SE), i the NRC staff finds that (1) the proposed method for power / flow exclusion region calculation using the LAPUR5 computer code, and (2) the VYNPS implementation of the SOLOMON stability monitor are acceptable. The NRC staff's SE is based, in part, on the attached technical evaluation report (TER) by Oak Ridge National Laboratory. I Prior to incorporating a power / flow exclusion region calculated by this methodology into the plant Core Operating Limits Report, this approved methodology should be referenced in the plant Technical Specifications.

Sincerely, I

? U C- -

C. Craig Harbuck, Acting Senior Project Manager Project Directorate I-1 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket No. 50-271

Enclosure:

Safety Evaluation w/ attached TER cc: See next page f

l

i ,

1 l

I i-D. Reid Vermont Yankee Nuclear Power Station Vermont Yankee Nuclear Power Corporation l cc:

Regional Administrator, Region I G. Dana Bisbee, Esq. i U. S. Nuclear Regulatory Commission Deputy Attorney General  !

475 Allendale Road 33 Capitol Street  !

King of Prussia, PA 19406 Concord, NH 03301-6937 R. K. Gad, III Resident Inspector Ropes & Gray Vermont Yankee Nuclear Power Station One International Place U.S. Nuclear Regulatory Commission Boston, MA 02110-2624 P.O. Box 176 Vernon, VT 05354 Mr. Richard P. Sedano, Commissioner Vermont Department of Public Service Chief, Safety Unit 120 State Street, 3rd Floor Office of the Attorney General Montpelier, VT 05602 One Ashburton Place, 19th Floor Boston, MA 02108 l

Public Service Board i State of Vermont Mr. David Rodham, Director i 120 State Street ATTN: James Muckerheide '

Montpelier, VT 05602 Massachusetts Civil Defense Agency 400 Worcester Rd.  !

Chairman, Board of Selectmen P.O. Box 1496  ;

Town of Vernon Framingham, MA 01701-0317 i P.O. Box 116 Vernon, VT 05354-0116 Mr. Raymond N. McCandless Vermont Division of Occupational Mr. Jay Thayer, Vice President and Radiological Health Vermont Yankee Nuclear Power Administration Building Corporation Montpelier, VT 05602 Ferry Road Brattleboro, VT 05301 Mr. J. J. Duffy Licensing Engineer Vermont Yankee Nuclear Power Corporation 580 Main Street Bolton, MA 01740-1398 Mr. Robert J. Wanczyk, Plant Manager Vermont Yankee Nuclear Power Station P.O. Box 157, Governor Hunt Road Vernon, VT 05354 i Mr. Ross B. Barkhurst, President l Vermont Yankee Nuclear Power Corporation j Ferry Road Brattleboro, VT 05301

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