ML20097A187

Proposed Tech Specs Revising Certain CR Scram Insertion Time Testing Limits

ML20097A187
Person / Time
Site:	Duane Arnold
Issue date:	01/30/1996
From:	IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT
To:
Shared Package
ML20097A175	List: ML20097A187 NG-96-0063, Application for Amend to License DPR-49,proposing Rev to Ts. Proposed Change Will Revise CR Scram Insertion Time Testing Limits
References
NUDOCS 9602050200
Download: ML20097A187 (5)

Text

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RTS-289 Attachment 2 to

. . NG-96-0063 Page1 of1 PROPOSED CHANGE IRTS-2891 TO THE DUANE ARNOLD ENERGY CENTER TECHNICAL SPECIFICATIONS The holders of license DPR-49 for the Duane Arnold Energy Center propose to amend Appendix A (Technical Specifications) to said license by deleting cenain current pages and replacing them with the attached, new pages. The List of Affected Pages is given below.

LIST OF AFFECTED PAGES l

3.3-5 i i

SUMMARY

OF CHANGES:

The following list of proposed changes is in the order that the changes appear in the Technical Specifications (TS). ,

Page Description of Changes 3.3-5 Changes the average control rod scram insertion time limit specified in Section 3.3.D.1 for rod position 46 from "0.35" '

seconds to "0.44" seconds.

3.3-5 Changes the average control rod scram insertion time limit for the three fastest control rods in all groups of four control rods in a 2X2 array specified in Section 3.3.D.2 for rod position 46 from "0.37" se.conds to "0.44" seconds.

9602050200 960130 PDR ADOCK 05000331 p PDR

DAEC-1 LIMI' TING CONDITION FOR OPERATION SURVEILLANCE REQUIREMENT l 3. During operation with Limiting 3. When a Limiting Control Rod Pattern Control Rod Patterns, either: exists and one RBM channel is.

l l a. both RBM channels shall be OPERABLE, inoperable, an Instrument I or Functional Test of the operable RBM channel shall be performed within l b. with one RBM channel inoperable, control rod withdrawal shall be 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to rod withdrawal.

blocked within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, unless OPERABILITY is restored within this time period, or l c. with both RBM channels inoperable, control rod withdrawal shall be blocked until OPERABILITY of at least one channel is restored.

1 D. Scram Insertion Times D. Scram Insertion Times l

1. The average scram insertion time, 1. After each refueling outage all based on the deenergization of the OPERABLE rods shall be scram time scram pilot valve at time zero, of tested from-the fully withdrawn all OPERABLE control rods in the position to the drop-out of the reed reactor power operation condition switch at the rod position required shall be no greater than: by Specification 3.3.D. The nuclear i system pressure shall be above 950 psig (with saturation temperature). l*

This testing shall be completed-Average Scram prior to exceeding 40% pow.er.

Rod Insertion During all scram time testing below Position Times (Sec) 20% power, the Rod Worth Minimizer shall be OPERABLE or a second 46 -1H W O N Y licensed operator shall verify that 38 . 7 the operator at the reactor console 26 1.86 is following the control rod 06 3.41 program.

2. The average scram insertion times for the three fastest control rods of all groups of four control rods in a 2 x 2 array shall be no greater than:

Average Scram Rod Insertion Position Times (Sec) 46 4dm O.W 38 .1 26 1.97 06 3.6R

3. Maximum scram insertion time to rod position 04 of any OPERABLE control rod should not exceed 7.00 seconds.

Amendment No. 720,J A2,180 3.3-5 MAR 111992

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RTS-289 Attachment 3 to

. NG-96-0063 I

Page1ofI l

. SAFETY ASSESSMENT '

i

By letter dated January 30,1996, IES Utilities Inc. submitted a request for revision of the Technical Specifications (TS) for the Duane Arnold Energy Center (DAEC). The l

proposed amendment would increase the required average control rod scram insertion j time to position 46 from 0.35 seconds to 0.44 seconds for all Operable control rods and j increase the required average control rod scram insertion time to position 46 from 0.37 to j 0.44 seconds for the three (3) fastest control rods for all groups of four (4) control rods in

a 2X2 array.

Assessment:

i The amount of reactivity inserted at rod position 46 (corresponding to 5% of rod  !

insertion) is small and the time required to insert this amount of reactivity is not j explicitly considered in the plant transient analysis. A generic BWR/2-5 study l performed on behalf of the BWR Owner's Group has demonstrated that relaxing the l 5% rod insertion time requirement had a negligible impact on plant transient I performance. We have confirmed that this generic study is applicable to the DAEC. I Increasing the allowable average scram insertion time to rod position 46 for all Operable control rods in addition to increasing the allowable average scram insertion I time to rod position 46 for the three fastest control rods in any 2X2 array would still demonstrate that the CRD system will perform its intended function.

Consequently, based upon the above, we have concluded that the proposed mereases m j average control rod scram insertion time for all Operable control rods to rod position 46 i to 0.44 seconds and for the three fastest control rods for all groups of four in a 2X2 array to position 46 to 0.44 seconds are acceptable.

1 i

RTS-289 Attachment 4 to NG-96-0063 Page1of1 ENVIRONMENTAL CONSIDERATION 10 CFR Section 51.22(c)(9) identifies certain licensing and regulatory actions which are eligible for categorical exclusion from the requirement to perform an environmental assessment. A proposed amendment to an operating license for a facility requires no environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significant hazards consideration; (2) result in a significant change in the types or significant increase in the amounts of any effluents that may be released offsite; and (3) result in a significant increase in individual or cumulative occupational radiation exposure. IES Utilities Inc. has reviewed this request and determined that the proposed amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9). Pursuant to 10 CFR Section 51.22(b),

no environmental impact statement or environmental assessment needs to be prepared in connection with the issuance of the amendment. The basis for this determination follows:

Basis The change meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9) for the following reasons:

1. As demonstrated in Attachment I to this letter, the proposed amendment does not involve a significant hazards consideration.

2. The proposed amendment includes changes which have been evaluated generically for BWR/2-5 plants to have a negligible impact on plant transient performance. This change does not significantly impact any safety analysis or threaten any safety limits. This change will not adversely affect normal or transient plant operation. There will be no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

3. The proposed amendment includes changes which have been evaluated generically for BWR/2-5 plants to have a negligible impact on plant transient performance. This change does not significantly impact any safety analysis or threaten any safety limits. This change will not adversely affect normal or transient plant operation. There will be no significant increase in either individual or cumulative occupational radiation exposure.

RTS-289 Attachment 5 to NG-96-0063 Page1ofI O GENuclearEnergy GeneralBecueCompany tis cunnerAmve.sanJose.cA sstzs SIE~-96001 DRF A12-000384 cc: Matt Brandt, Duane Arnold.

January 4,1996 LS. Post, GE R. E; Kingston, GE~

To: Ron Ballou, GE From: Nader Sadeghi

Subject:

Slow ScramTunes at 5% Insertion Duane Arnold requested that GE evaluate the importance of the degradation of 5%

insertion time. The purpose of this letter is to respond to this request.

The degradation of the 5% insertion time for the core average does not significantly impact any safety analysis or threaten any safety limits. The 5% insertion time has been relaxed for BWR/2-5s as part of the standard Improved Technical Specification (ITS) upgrade (EAS-56-0889, BWR/2-5 Scram Time TMhnical Specification, August 1989).

The change in the 5% insertion scram time to 0.44 see was generically assessed for the-most limiting transient (load rejection without bypass) to have less than a 0.01 impact on-the ACPR. This impact is considered negligible in view that the operating limit MCPR is based on average scram speed, but faster mds insert more scram reactivity than the slower rods. Meeting the 20% insertion time is more important in its effect on transient performance than meeting the 5% insertion time requirement because the peak total reactivity of the load reject without bypass event occurs sometimes after 0.44 sec. The ODYN Option B type requirements only have the 20% insertion point.

In the event that the original 5% insertion time required by Tbchnient Specifications is not met, the safety limit MCPR would not be exceeded if the insertion time to 5% does not exceed the ITS value of 0.44 see and the 20% insertion does not exceed its limit.

Please call me if there are any questions on this information.

.a sa 4 L:.

N. Sadeghi. Senior Engineer (408) 925-1162, M/C 747