ML20073A079

Application for Amend to License NPF-86,changing Tech Specs 3.1.5 Re Rod Drop time,3.1.3.5 Re Shutdown Rod Insertion limit,3.1.3.6 Re Control Rod Insertion Limit & Bases 3/4.1.3 Re Movable Control Assemblies

ML20073A079
Person / Time
Site:	Seabrook
Issue date:	04/12/1991
From:	Feigenbaum T PUBLIC SERVICE CO. OF NEW HAMPSHIRE
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20073A082	List: ML20073A079 ML20073A089
References
NYN-91059, NUDOCS 9104230031
Download: ML20073A079 (3)

Text

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New Hampshire fed C. Feigenbaum

- Presdent and Chief trocutive Officer NYN. 91059 April 12,1991

. United States Nuclear Regulatory Commission Washington, D.C. 20$$$

Attention: Document Control Desk

Reference:

Facility Operating License No. NpF.86, Docket No. 50 443

Subject:

~ Request for License Amendment; Rod Cluster Control Assembly (RCCA)

_ Repositioning Program Gentlemen:

. . . Pursuant to 10CFR50.90, New flampshire Yankee (NilY) hereby proposes to amend the Seabrook Station Operating License (Facility Operating License NPF 86) by incorporating.

the proposed changes provided herein as Enclosure 1, into the Seabrook Station Technical Specifications. Th!s request for a license amendment is submitted in support of NIIY's plans to implement a Rod Cluster Control Assembly (RCCA) repositioning program. The proposed RCCA repositioning program permits the- axlat repositioning of the RCCAs between (and

, including) 225 and 232 steps withdrawn during power operation The implementation of the RCCA. repositioning program is expected to yield even distribution of RCCA wear on the -

rodlet cladding. and a longer operating ' lifetime for the RCCAs. The RCCA- wear phenomenon in Westinghouse plants was described in USNRC Information Notice 8719, ni

' Perforation and Cracking of Rod Cluster Control A$riemblies'. i The proposed changes effect the following Technical Specifications and Bases:

Technical ~ Snecification 3.1.4 (Rod Dron Time) nace 3/4120 Currently, rod drop times are determined by dropping rods from the ' fully withdrawn position (228 steps withdrawn). . The change to this specification will require that rods be dropped from the ' mechanical fully withdrawn' i position which is expected to be either 230 steps or: 231 steps during hot conditions. Engineering evaluations of the RCCA repositioning program have addressed rod positions between 225 and 232 steps withdrawn to envelope the expected mechanical fully withdrawn position. The drop time requirement of 2.2 seconds contained in this specification is not changed, therefore all accident analyses which credit rod insertion remain valid. NHY will not utilize the rod positions above 228 steps until drop times above 228 steps are confirmed to '

be.within- this Technical Specification limit. The maximum - measured rod drop time at Seabrook' Station.of 1.45 seconds is estimated to increase to 9104230031 910412 i PDR -ADOCK 05000443 t P- PDR

'g8 New Hampshire Yonwee Division of Public Service Company of New Hampshire I -

M. rbd s [! 1- P.O. Box 300

• Seabrook, NH 03874

• Telephone (603) 474 9521. 'I l

United States Nuclear Regulatory Commission April 12,1991 Attention: Document Control Desk Page two 1.498 seconds if rods were dropped from 232 steps (eg 4 steps beyond 228),

nevertheless, NilY will test the drop times for positions above 228 prior to use.

. Technieni Soccifiention 3.1.3.5 (Shutdown Rod insertion 1,imit) once 3/4121 The change to this specification involves the addition of a definition for ' fully withdrawn' (eg 'The fully withdrawn position is defined as the interval within 225 to the mechanical fully withdrawn position, inclusive *) This change allows the axial repositioning of the shutdown rod banks within this band during power operation. NIIY will develop procedures for implementation of the RCCA repositioning program for the shutdown rod banks.

. Technical Specifiention 3.1.3.6 (Control Rod Insertion Limits) Finure 3.11. once 3/4123 The change to figure 3.11 which depicts the required positions for control rod banks as a function of thermal power level involves the addition of a definition for ' fully withdrawn' consistent with the change to specification 3.1.3.5 above.

This change rllows control rod banks that were previously maintained at a parked position of 228 steps to be axially repositioned within the range of 225 steps to the mechanical fully withdrawn position, inclusive. N11Y will develop procedures for implementation of the RCCA repositioning program for the control rod banks.

. Technical Soerification Bases 3/4.1.3 once Il 3/4 1-4 (Movable Control Assemblies)

The changes to this Bases section are consistent with the Techn cal i Specification changes proposed herein and specify that rod drop times are measured from the " mechanical fully withdrawn position" and that the fully withdrawn position of shutdown rod banks and control rod banks can be varied between 225 steps and the mechanical fully withdrawn position (up to 232 steps) inclusive. The changes to this Bases section also specify that the 225 to 232 step interval allows axial repositioning to minimize RCCA wear, in accordance with 10CFR50.36 these Bases are not considered to be part of the Technical Specifications.

New ilampshire Yankee has evaluated the proposed Technical Specification changes utilizing the criteria specified in 10CFR50.92 and has determined that the proposed changes do not involve a Significant Hazards Consideration pursuant thereto The Significant 11azards Consideration evaluation is provided herein as Enclosure 2.

i

United States Nuclear Regulatory Commission April 12,1991 Attention: Document Control Desk Page three New linmpshire Yankee requests approval of the Technical Specification changes proposed herein by September 1,1991, in support of expeditious implementation of the RCCA repositioning program. l Should you have any questions regarding this request, please contact Mr. Terry L. I Ilarpster, Director of Licensing Services, at (603) 474 9521, extension 2765.

Very truly yours, fgg.,h/stbW Ted C. Felgenbaum TCP:ALL/act/ssi i cc: Mr. Thomas T. Martin Regional Administrator United States Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Mr. Gordon E. Edison, Sr. Project Manager Project Directorate I.3 Division of Reactor Projects U.S. Nuclear Regulatory Commission Washington, DC 20555 l Mr. Noel Dudley NRC Senior Resident inspector

. P.O. Box 1149 Seabrook, NH 03874 State of Nil State Liaison Office l