BVY-90-084, Notifies NRC of Intentions to Install Test Fuel Assemblies & Test Control Blades During Cycle 15 Refueling Outage in Sept 1990

Notifies NRC of Intentions to Install Test Fuel Assemblies & Test Control Blades During Cycle 15 Refueling Outage in Sept 1990

ML20055H476
Person / Time
Site:	Vermont Yankee
Issue date:	07/24/1990
From:	Tremblay L VERMONT YANKEE NUCLEAR POWER CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
BVY-90-084, BVY-90-84, NUDOCS 9007260252
Download: ML20055H476 (2)

Text

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1 (VERMONT YANKEE "NUdLEAR POWER CORPORATION 1 1

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Ferry Road, Brattleboro. VT 05301-7002 ENGINEERING OFFICE

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580 MAIN STREET i DOLTON, MA 01740 l (508)779-6711 'I 1

July 24,1990 United States Nuclear Regulatory Commission BVY 90-084

. Document Control Desk -

Washington, DC 20555 - *

References:

a. License No. DPR-28 (Doccet No. 50-271)

b. Letter, VYNPC to USNRC, dated February 28,1990.

c. Letter, USNRC to VYNPC, dated June 5,1990. ,

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Subject:

Vermont Yankee Cycle 15 Refueling Plans

Dear Sir:

P

. The purpose of this letter is to formally notify NRC of Vermont Yankee's intention to install test fuel assemblies and test control o' lades in the Vermont Yankee core during the upcoming September,1990 refueling outage. These plans have been discussed in detail with members of your staff during a visit by mpresentatives of Vermont Yankee to NRC headquarters on May 2, 1990 and again by means of telephone conversations on June 26 and July 16,1990.~

Fuel Assemblies

' Vermont Yankee plans to load four Advanced Nuclear Fuels Corporation (ANF) 9X9 IX test L fuel assemblies into the Cycle 15 core. These fuel assemblies have been designed to: (1) match the e

coresident GE-9B fuel assemblies, (2) use the GE-9B operating limits, (3) have negligible effect

-on core-wide transient performance, and (4) meet applicable safety criteria during postulated core-wide transients and accidents. Vermont Yankee has determined that the installation of the four  !

ANF test fuel assemblies will have a negligible affect on plant operations.

4 With regard to NRC criteria for installation of test fuel assemblies, your staff stated that there

' were two applicable conditions: (1) the total number of test fuel assemblies should not exceed 20  ;

assemblies in the core, and (2) the test fuel assemblies should not be installed in any limiting location. Limiting, in this case, refers to limiting thermal margins at any point during the cycle.

Since Vermont Yankee intends to install only four test fuel assemblies into the Cycle 15 core, in ,

locations that will not be limiting during the cycle, our plans meet the stated NRC criteria for installation of test fuel assemblies. In addition, your staff r*ated that the applicable ANF topical reports need not be added to the Vermont Yankee Technical Specifications at this time, since the fuel assemblies are being installed as test assemblies.

Control Blades >

In Reference (b), Vermont Yankee stated its intention to utilize as many as eight General Electric " Marathon" control blades in the Cycle 15 core. These longer-life control blades utilize a 900726023' 900724 DR ADOCh 05000271 PDC Od[

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United States Nuclear Regulatory Commission July 24,1990

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combination of B4C and hafnium as the neutron absorbing material. Reference (b) provides a complete 10CFR50.92 significant hazards evaluation for the use of hafnium in control blades at Vermont Yankee. The NRC recently approved use of hafnium in Vermont Yankee control blades by means of Amendment No.123 to the Vermont Yankee Technical Specifications [ Reference (c)].

The General Electric topical repon for the Marathon blades is currently under review at NRC,

- Recent discussions with your staff have revealed that the General Electric topical report may not be ~

approved prior to installation of the Marathon control blades during our scheduled September, 1990 refueling outage and that Vermont Yankee should pursue installation of the ' Marathon blades as test control blades. Your staff stated to us that installation of the Marathon contml blades in the Vermont Yankee core as test control blades would follow similar criteria as installatinn of test fuel-assemblies,in that:. (1) the total number of test control blades installed in the core should not exceed a range of 10 to 12 blades, and (2) the test control blades should not be ir. stalled in any limiting location. Limiting, in this case, refers to cold shutdown margin at any point during the cycle. Since Vermont Yankee intends o install no more than eight test control blades into the Cycle 15 core, in locations that will not be limiting during the cycle, our plans meet the stated NLC criteria for installation of test control blades.

Vermont Yankee plans to install the test fuel assernblies and control blades under 10CFR 50.59. The Plant Operations Review Committee will review these plans prior to installation.

We believe that these two changes demonstrate Vermont Yankee's proactive approach 'n the area of fuel and core component management. The changes should ultimately lead to improved fnel reliability and should significantly contribute to improved core component service life.

- Snould you have any question', with regard to the above described plans, please contact this office.

Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION QYG A i s Leonard A. Tremblay, Jr. (

Senior Licensing Engineer

. cc: USNRCRegioni Administrator USNRC Resident Inspector- VYNPS USNRC Project Manager- VYNPS l

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