ML20079L136

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Application for Amend to License NPF-58,revising Tech Spec 3.1.3.2, Control Rod Max Scram Insertion Times, in Order to Clarify Under What Conditions Shutdown of Plant to Hot Shutdown Is Required
ML20079L136
Person / Time
Site: Perry FirstEnergy icon.png
Issue date: 10/30/1991
From: Lyster M
CENTERIOR ENERGY
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20079L137 List:
References
PY-CEI-NRR-1379, NUDOCS 9111060106
Download: ML20079L136 (5)


Text

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CENTERDOR l ENERGY l - - _ - - - . . . _

PERRY NUCLEAR POWER PLANT t i Ad ess.

fAlchael D Lyster o ct ^ PERRY. Hi 44081 VICE PHI SIDE tn . NUCLE An n 4 i (210) ?$9 3737 October 30 1991 3 PY-CEI/NKR-1379 L U.S. Nuclear Regulatory Commission Document Control Desk

  • Vashington, D. C. 20555 Perry Nuclear Power Plant Docket No. 50-440 Technical Specification Change Request - Technic".

Specification 3.1.3.2 -

Control Rod Maximum Scram Insertion Times Gentlemen Enclosed is a request for amendment to the Perry Nuclear Power Plant (PNPP)

Unit 1 Facility Operating License NPP-58. In accordance with the requirements of 10CPR50.91(b)(1), a copy of this request for amendment has been sent to the State of Ohio as indicated below.

This amendment sequests revision of Technical Specification 3.1.3.2 " Control Rod Maximum Scram Insertion Times" in order to clarify under what conditions shutdovn cl the plant to HOT SHUTDOVN is required.

Attachment 1 provides a Summary, Description of Changes, and the Significant Hazards and Environmental Considerations. Attachment 2 provides a copy of the proposed Technical Specification change.

If you have any questions, please feel free to call.

Eincerely, i

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, Attachment 1 pY-CE!/NRR-1379 L page 1 of 4

SUMMARY

The proposed change vill clarity the intent of statements in the Technical Specifications. Currently. ACTIONS a, b and c of Specification 3.1.3.2

" Control Rod Maximum Scram Insertion Tienes," each conclude with "Otherwise be in at least HOT SilVTDOVN vithin 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />." One unforeseen tesult of this was an apparent decoupling of the individual ACTIONS such that it is not possible to pass from One ACTION to another. This ptoposed change vill add a phrase in ACTION a.1 to allow continued operation 11 the compensatory requitements of ACTION b are carried out. As currently formatted, the failure of a single control rod drive to meet the scram insertion limits of ACTION a.1 could be interpreted so as to force the plant to be in 110T SHUTDOVN vithin 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This is in direct contradiction to ACTION b vhich allows continued plant opetation if specified actions are taken to compensate for control rods that do not meet the limits of ACTION a.l.

ACTION c.2 vill be modified slightly te adjust for the change to ACTION a.l.

Additionally, ACTIONS a.3 and a.4 vill be modified to temove an inappropriate reference to individual " fast" control iods, in order to avoid the possibility of the Specifications leading to an unnecessary teactor shutdovn. The General Electric Company supports that the references to

" fast" control rods in ACTIONS a.3 and a.4 should be deleted to appropriately conform with the basis for the Specification.

DESCRIPTION AND JUSTIFICATION OF THE pH0p0 SED CilANGE During individual control tod scram time testing on Hay 19, 1990, a conttol rod appeared to have a scram insertion time greater than allowed by the LCO and ACTION a.l. It was determined before the expiration of the 12 hout Action Statement that the problem was with the test equipment, not the drive. Compliance with the Action Statement vould have tequited plant shntdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the tod itself had actually been slow. The '

first portion of this change request is proposed in ordet to avoid such unnecess n y plant shutdovns.

As noted above, the current Action statements contain separate but identical requirements to "Otherwise, be in at least il0T SilUTD0VN vithin 12 houts."

The proposed change vill simply cir4rify that the Actions are intetdependent, 4 since it is the intent of the Specification that ACTION b is a contingency to be exercised if the ACTION a.1 time limits cannot he met for a control rod during scram time testing.

ACTION a.1 vas the location chosen to present scram times that are slover than the normal scram times in the Table at the top of the LCO 3.1.3.2 page, but which do not result in the need to declate the control tod inoperable. ACTION a.1 is referenced in ACTION h and ACTION c.2. ACTION b delineates compensatory actions to be performed if control rods do not satisfy the times in ACTION a.1. It was intended as a means to provide a mechanism to allow continued operation (with cestain testrictions) in the event'a control rod does not meet the maximum scram insertion times specified in ACTION n.l. However, the requir ement at the end of ACTIONS a e

and c to be in at 1 erst HOT SilVTDOVN vithin 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if ACTIONS a or c cannot be met appears to preclude utilizing the provisions of ACTION b.

This change vill clarify th8t ACTION b may be utilized to permit continued plant operation in the event a control tod does not meet the ACTION a.1-scram times, consistent with the intent of the specification.

. Attachment 1

. pY-CEI/NRR-1379 L page 2 of 4 The vords "the limits of" are to be deleted from ACTION c.2 since the '

earlier proposed change to ACTION a.1 expands the scope of ACTION a.1 beyond scram insertion' time limits .o include a reference to ACTION b. Because  ;

ACTION a.1 has the reference to ACTION b, no reference in ACTION c.2 to ACTION b is required.

The proposed changes deset d above correct one inconsistency vith the I intent of the specification, thereby eliminating a potential compliance  ;

problem.

It also results in a significant improvement in plant safety as there is now a mechanism to utilize an existing alternative (ACTION b) so as to avoid entering the shutdown process, with the increased inherent chances of plant trips and the cycling of plant components.

f During the development of the basis for the above described change, it became apparent that changes should be made to ACTIONS a.3, a.4 and c.4 to address another situation that is inconsistent vith the safety analyses that i support this specification. ACTIONS a.3 and a.4 discuss a subset of the  ;

" fast" control rods, i.e., those that meet the criteria of Specification 3.1.3.2 but do not meet the criteria of ACTION a.2. Vhen the LCO is entered due to a " slow" control rod, requirements for the othe control rods (i.e.,

.the " fast" control rods) are provided in ACTION a.2, which specifies the average scram time of all the control rods which meet the criteria of

-Specification 3.1.3.2 an avarage which is not intended to be applied to an individual control rod as is currently stated in ACTIONS a.3 and a.4.

ACTIONS a.3 and a.4 should only be applied to those control rods which do not meet the criteria of Specification 3.1.3.2 (i.e., "slov" control rods) ,

and those control rods which are considered inoperable.

ACTION c.4 vill be revised to be consistent with the nev ACTION a.3 by replacing the vord " sum" with " total number".

ACTION a.2.provides the acceptance criteria 1for an average of the scram insertion times of "those (control rods) which satisfy the limits of Specification 3.1.3.2." The basis for the Specification is scram reactivity calculations that vere performed by the General Electric Company and assumed ,

that the:e vere eight inoperable fully withdrawn control rods (which vere assumed to insert =only after the transient was over), seven other rods with scram times in excess of Specification 3.1.3.2 but not in excess of ACTION a.1 (" slow" but not inoperable), and an additional (highest teactivity worth) control rod stuck in the fully withdrawn position. The analysis assumed the "slov" and inoperable control rods met the applicable spacing requirements of ACTION a.4 and Specifications 3.1.3.1 and 3.1.4.2, and the maximum allovable average scram time for all the non-inoperable, non-slov, o and non-stuck-rods (as a group) vas calculated which would still provide l assurance that the scram reactivity cutve vould be met even with all of .

these inoperable, "slov," and stuck control rods. This result is reflected as ACTION a.2. During development of Specification 3.1.3.2, a previous version of the Specification had mistakenly applied the scram time limits of ACTION a.2 as the maximum allowable individual scram time for all non-inoperable, non-slow, and non-stuck rods. This erroneously created a class of-control tods whose-times vere between the limits of ACTION a.2 and l

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Attachment 1 pY- CEl / NRR- 13 79 1.

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page 3 of 4 the limits of Specification 3.1.3.2, and these rods vote then treated in the same mannet as " slow" control rods for the putposes of separation (ACTION a.4) and limit on the number of slow" centt ol t ods ( ACTION a.3). ACTION a.2 vas corrected in later versions to be a limit on the avetage setam time, however, ACTIONS a.3 and a.4 vere not accordingly cort ectMIE1Iius, it can be seen that it is inappropriate to apply any separation critetia 'o those individual Operable control tods vhich meet the setam time limits of Specification 3,1.3.2.

The proposed change corrects this othet inconsistency desettbed above, thereby eliminating anothet potential compliance problem. It, too, tesults in a significant imprevement in plant safety by avoiding an unnecessaty shutdown process, with the increased inherent chances of plant trips and the cycling of plant components.

PR0p0 SED CilANGE Revise Technical Specification 3.1.3.2 ACTION a.1 by adding "ot the requirements of ACTION b are satisfied" and temoving the vords "the limits of" from ACTION c.2. The intent of the changes is to allow continued plant operation by using the existing contingency sequitements listed in ACTION b in the event control rod scram times are in excess of tMse soecified in ACTION a.l.

Revise Technical Specification 3.1.3.2 ACTION a.3 by replacing the vords

" sum of ' fast' control rods with individual sciam insertion times in excess of the limits of ACTION a.2 and" with " total numbet." Similatly, in ACTION c.4, replace the voto " sum" with "tetnl number".

Revise Technical Specification 3.1.3.2 ACTION a.4 by deleting the words ",

' fast' control rod with individual scram insertion time in excess of the limits of ACTION a.2.".

SIGNIFICANT llAZARDS CONSIDERATION The standards used to arrive at a determination that a request for amendment involves no significant hazards considerations ate included in the Commission's Regulations, 10CFR50.92, which state that the opetation of the facility in accordance with the proposed amendment vould not (1) involve a significant increase in the probability or consequences of an accident previously evaluated (2) create the possibility of a new ot different kind of accident from any previously evaluated, or (3) invoh e a sigaificant reduction in a margin of safety.

The proposed amendment has been reviewed with respect to these thtee factots and it has been determined that the proposed change does not involve n significant hazards consideration becauset

Attachment 1 PY-CEl/NRR.1379 L j Page 4 of 4

1. This change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

The proposed changes to ACTION a.1 and c.2 ensure that the intent of the current Actions remains unchanged. In the event a control rod exceeds the maximum scram insertion time, operation may continue if specified compensatoty actions are taken. The change also removes vords f rom ACTIONS a.3 and a.4 that are not consistent with the basis for the scram time specification, thus restoring the original intent of the Actions. ACTION c.4 is simply tovised to be consistent with the change to ACTION a.3. The proposed voiding changes do not affect the probability of occurrence of an accident since they only address administrative declarations of control rod inoperability and administrative checks of control rod spacing in order to ensure compliance with the basis of the Specification. The proposed wording does not change the basis for the setam time Specification requirements, ond, since the basis for the Specification vill still be met if the proposed Actions ate met, the consequences of any previously evaluated accident also do not change.

2. This proposed change does not eteate the possibility of a new or different kind of accident from any previously evaluated. The proposed change does not change the mechanism by which scrams are accomplished or scram times are calculated, nor does it change any of the hardware associated with the control tod drives or the scram pilot solenoids.
3. ibe proposed change does not involve a significant teduction in a margin of safety. The proposed change does not reduce a margin of safety as defined in the Bases for the Technical Specifications.

This change does not modify any of the maximum scram insertion times. Therefore, the proposed change does not involve a significant reduction in a margin of safety.

s Based upon the above considerations, it is concluded that this proposed change does not involve a significant hazards consideration.

ENVIRONMENTAL CONSIDERATION The proposed Technical Specification change request has also been revieved against the criteria of 10CFR51.22 for environmental considerations. As shown above, the proposed change does not involve a significant hazards consideration, nor increase ;he types and amounts of effluents that may be released offsite, nor cignificantly increase individual or cumulative

ccupational radiation exposures. Based on the foregoing, it is concluded that the proposed Technical Specification change meets the criteria given in 10CFR51.22(c)(9) for a categorical exclusion from the requirement for an Environmental Impact Statement.

SC/ CODED /3201

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