ML20148P634

Safety Evaluation Supporting Amend 14 to License NPF-57

ML20148P634
Person / Time
Site:	Hope Creek
Issue date:	01/19/1988
From:	Office of Nuclear Reactor Regulation
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ML20148P618	List: ML20148P626 ML20148P634
References
NUDOCS 8801290197
Download: ML20148P634 (6)

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULAT SUPPORTING AMENDMENT NO.14 TO FACILITY OPERATING LICENSE N PUBLIC SERVICE ELECTRIC & GAS COMPANY ATLANTIC CITY ELECTRIC COMPANY HOPE CREEK GENERATING STATION l

DOCKET NO. 50-354 I

1.0 INTRODUCTION

By letter dated November 9, 1987, Public Service Electric & Gas Company (PSE&G) requested an amendment to Facility Operating License No. NPF-57 for the Hope Creek Generating Station. The proposed amendment would {

change the Technical Specifications (TS) for the Hope Creek Generating l Station by:

(1) adding the following definitions for SPIRAL RELOAD and SPIRAL UNLOAD:

A SPIRAL RELOAD is a core loading methodology employed to refuel the core after a complete core unload. During a SPIRAL RELOAD the fuel is to be loaded into individual control cells (four bundles surrounding moving a control blade) in a spiral fashion centered on an SRM outward.

Before initiating a SPIRAL RELOAD up to four bundles may be loaded in the four bundle locations immediately surrounding count rate. each of the four SRMs to obtain the required channel  ;

A SPIRAL UNLOAD is a core unloading methodology employed to defuel when the complete core is to be unloaded.

The core unload is performed by first removing the fuel from the outermost control cells (four bundles surrounding a control blade). Unloading continues in a 8801290197 880119 PDR P ADOCK 05000354 PDR

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l spiral fashion by removing fuel from the outernost periphery to the interior of the core, symetric about the SRMs, except for the four bundles around each of the four SRMs. When sixteen or less fuel bundles are in the core, four around each of the four SRMs, there is no need to maintain the required channel count rate.

(2) changing the Source Range Monitor (SDM) operability requirements in TS j

3.9.2. to ellow the SRM neutron count rate to drop below three counts per second during SPIRAL RELOAD and SPIRAL UN'.0AD when there are sixteen or

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less fuel bundles in the core comprising four or less fuel bundles in the  !

four bundle locations imediately surrounding each of the four SRMs. I i

(3) deleting the TS 4.9.2 surveillance requirement to verify that the SRM .

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count rate is at least 0.7 cos or 3 cps prior to and at least once Der 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> whenever, per i+en 2 above, this count rate is not required. I (41 deleting the Limitino Conditions for Ooeration and Surveillance Requirements in TS 3/a.10.7 concerning SRM requirements during the initial core loading.

(5) changing ; elated Bases to make them consistent with the above changes.

l In describing its reasons for the change, PSE&G stated:

Hope Creek Generating Station (HCGS) is currently iaquired to demonstrate that a least two of the four SRM channels are OPERABLE during OPERATIONAL CONDITION 5 (Refueling) by in part verifying that tha channel count rate is at least 0.7 counts per second (cps)  !

provided the signal-to-noise ratio is greater than or equal to ?,

otherwise the count Specification rate must be at least 3 ces (Technical 4.9.2.c). This verification must be perforned prior to control rod withdrawal, prior to and at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> during CORE ALTERATIONS, and at least once per twenty-four hours. As indicated in the Bases Section, this requirement ensures that redundant capability is available to detect changes in the reactivity condition of the core (B 3/4.9.2), which during low power and startup conditions is only available from the SRMs (R 3/4.3.7.6).

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1 Should conditions require that HCGS completely unload the core, or if a situation exists which requires core unloading to be temporarily halted when only a small number of bundles remain in the reactor pressure vessel (RPV) (i.e., sixteen or fewerl, then SRM OPERABILITY must be demonstrated as described above prior to reloading the RPV nr centinuing the core unload. While this requirement does not in end of itself present a problem, due to either the lack of bundles in the core or the low number of bundles and their relative positions in the RPV, a portable !

source may have to be inserted into the core region to generate enough '

neutrons such that a count rate of 3 cps (or 0.7 eps, as appronriate) can be achieved. This action would produce unnecessery delays in CORE ALTERATIONS which would negatively impact outage scheduling.

Therefore, Public Service Electric and Gas Company (PSE&G) croposes to revise the referenced Technical Specifications removing the requirement to demonstrate SRM OPERABILITY whenever sixteen or fewer fuel bundles a,re in the core, thus avoiding the necessity of obtaining, inserting and removing a portable sample during refueling operations.

2.0 EVALUATION The changes described above in items 1 ? and 3 are directed at the Limiting Conditions for Operation and Surveillance Requirements for core monitoring during core alterations, and addresses Source Range Monitor (SRM) operability, via count rate, and fuel assembly loading limits. It specifically involves Specification 3/4.9.2 and related Definitions and Bases. During reload operations the TS require minimum count rate levels to be met by the SRM. During reload operations in a BWR in which the entire core is to be unloaded, especially if sources are not present, there may be tines (when there are few fuel assemt. lies in the core) when this minimum count rate can not he met with the usual SRM. For this condition, other monitors, Fuel Loading Chambers (FLC), usually called "Dunking Chambers" and/or sources, that can be moved from place to place in the core as loading proceeds, are frequently used as a replacement for the SRM. Furthermore, the FLO and sources are impediments to operations and it is thus desirable to keep their use to a minimum.

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During the past several years several utilities have requested TS changes to permit loading operations such that the use of FLC and/or sources can be avoided.

The reactors include Peach Botton, Browns Ferry, Hatch, Sasquehanna, Brunswick and Limerick. An example of such a procedure and relevant background and bases are discussed in the staff's SER for the most recently approved revision for Browns Ferry. As permitted by these changes, the loading operation for full core reloads involving irradiated fuel may begin without minimum count rates for the SRM for a limited number of assembly loadings (determined to be subcritical). These l'eadings place irradiated fuel adjacent to SRM locations.This provides (e.g., from gamma-neutron reactions) sufficient neutron source to meet the TS minimum SRM count rate requirements.

After the SRM is thus fully operational the loading proceeds in the usual manner, e.g.,

spiral leading from the center. The initial loading is acceptable because it is not possible to be critical, even with control rods removed, with the fuel configurations used.

PSEaG proposes, as described above in change items 1, 2 and 3 for Hope Creek, to be allowed to go below the recuired SRM count rate when there are not more than four fuel assemblies in each core quadrant, loaded around each of the four SRM positions for either loading or unloading operations.

For example, for a reinad in which all fuel assemblies and normal sources have been removed from the core, they first load up to four (as necessary) irradiated assemblies next to each of the four SRM locations, without necessarily meeting the required count rate until this loading is finished.

The loading would then continue in normal fashion, e.g., spiral loadino from the core center, and would have to meet the usual counting rate requirement. General Electric has calculated that the configuration of (any GE) four assemblies (2X? arravl at the maxieum reactivity condition (as a function of burnup), without control rods

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l inserted and separated from other assemblies by a distance of 12 inches would have a Kpff of less than 0.95. l Thus the above configuration is suberitical.

The proposed Hope Creek modifications to the SRM count rate requirement and the loading (and unloading) procedures to safely approach the required count rate are the same as (or similar to) those reviewed and approved for previous applications in this area by the other utilities.

Our review indicates that the pre-count configurations should indeed be subcritical and experience indicates that required count rates should be .

Pchieved with the irradiated assemblies next to the SRM. We, therefore, have concluded that the process and the requested changes as described in items 1, 2 and 3 above are acceptable.

The change described above in item 4 is directed at deleting TS 3/4.10.7 j

that was applicable to the initial core loading only. The initial core loading was completed in early 1986, and the TS is no longer applicable.

Therefore, we conclude that its removal is appropriate and acceptable.

We have also concluded that the changes to the Bases as described above in item 5 are acceptable.

3.0 ENVIRONMENTAL CNSIDERATION This amendment involves a change to e requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes to the surveillance reouirements.

The staff has determined that the amendment involves no significant increase in the amounts, and ne significant change in the types, of any effluents that may he released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure.

The Corrnission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there

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has been no public corcent on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.

4.0 CONCLUSION

i The Commission made a proposed determination that the amendment involves ,

no significant hazards consideration which was published in the Federal Reafster (52 FR 47790) on December 16, 1987 and consulted with the State i of New Jersey. No public comments were received and the State of New i Jersey did not have any comments.

The staff has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be ~

inimical to the common defense and security nor to the health and safety of the public, i

Principal Contributor: G. Rivenbark Dated: January 19, 1988