ML20066G131

Application for Amend to License NPF-62 & Exemption from 10CFR50,App J & Tech Spec 3/4.6.1.2 for Containment Penetrations Associated W/Feedwater Sys at Facility.Approval Requested Prior to Startup from Second Refueling Outage

ML20066G131
Person / Time
Site:	Clinton
Issue date:	01/18/1991
From:	Jamila Perry ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20066G136	List: ML20066G131 U-601784, Proposed Tech Specs Exempting Measured Type C Leakage Rates for Feedwater Check Valves 1B21-F032A & B
References
JSP-0041-91, U-601784, NUDOCS 9101240380
Download: ML20066G131 (12)

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'9 l g U-601784 l l L4 7-91 ( 01-18) -LP l h BE.100a CLINTON POWER 67 ATION. P,o. DOX 078. CLINTON. ILLINOIS 61727 0678. TELEPilONE (2171935 8881 j

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l 5:l JSP-0041-91 i January 18, 1991 l l 10CFR50.12 10CFR50.90 Docket No. 50-461 l

i i Document Control Desk-Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

Application for One-Time Exemption from 4 10CFR50 Appendix J and Technical' Specification 3/4.6.1.2 for containment Penetrations Associated with the Feedwater System at Clinton Power Station l

Dear Sir:

In accordance with 10CFR50.12 and 10CFR50.90, Illinois Power (IP) hereby applies for a one-time 4

exemption from 10CFR50 Appendix J and Clinton-Power l Station (CPS) Technical Specification 3/4.6.1.2 for the containment penetrations associated with the feedwater i system. Per 10CFR50 Appendix J paragraph III.C.3--and Technical Specification 3.6.1.2, " Primary Containment Leakage," item b, the combined leakage rate for all (ontainment penetrations and valves subject to Type B and

f. tests is limited to 0.60 La. Por Technical specification 3.6.1.2,_ item d, the combined leakage rate for all secondary containment bypass leakage paths is I

limited to 0.08 La. With respect.to these-requirements, '

IP requests an exemption to exclude-the. leakage rates associated with two particular feedwater system-containment isolation valves, 1B21-F032A and B, from these combined leakage rates for the third, operating--

cycle only.

Each of the two feedwater lines at CPS incorporates three isolation valves. These isolation' valves consist of a simple check valve (1B21-F010A(B)] inside the drywell, an air-assisted check valve (1821-F032A(B)) just outside the primary containment.and a remotely controlled, motor-operated gate valve (1821-F065A(B))

further outside containment. Each'of'the valves noted above is listed on Technical Specification Table 3.6.4-1,

" Containment Isolation Valves," and each is required to be Type C leak rate tested =per Technical Specification Surveillance Requirement _4.6.1.2.d. The Type C leakage- i rate determined.for any particular containment. i penetration _(i.e., for the containment isolation valves- l

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s U-601784 associated with that penetration) is based on the

" maximum pathway" loaxage in which the valve with the smallest lenkage rate is assumed to fail to close. To date, the maximum pathway leakage rate reported for each of the feedwater penetrations, in consideration of the three isolation valve arrangement, was based upon the leakage rate of the valve with the ovcond smallest-leakage rate in accordance with CPS Updated Safety Analysis Report (USAR) Table 6.2-47, note 24. As a result, the leakage rate of the worst of the three valves (i.e. ,1B21-F032A and B) was excluded in the determination of the Type C leakage rate of these penetrations and therefore was also excluded from the combined leakage rates.

As a result of discussion with the NRC Staff on January 8, 1991, it was determined that the maximum pathway leakage of a feedwater penetration should be based upon the leakage rate of the check valve with the largest leakage rate. This is based upon not taking credit for valves 1B21-F065A and B as containment isolation barriers because they do not close in response to an automatic isolation signal.

The design of check valves 1B21-F032A and B (which utilizes a tilting disk and hard seat) makes it extremely difficult to achieve and maintain acceptable air leakage rates. IP nas performed an extensive rowerk of these valves and the valves have successfully passed'a 1000 pounds por square inen water leak rate test. However, IP has been unable to achieve acceptable air leakage results. (Individual leakage rates obtained for these valves after extensive rework during the current refueling outage exceeded the test instruments' range of 20,000 standard cubic centimeters per minute). IP believes that a more permanent and effective solution (which would likely involve changes to the current design) is required to obtain acceptable air leakage results and to ensure lasting performance of-these valves. Approval of this request would' provide IP-adequate time to evaluate the various alternatives and adopt the best solution. The third refueling outage would provide the earliest opportunity to implement the i

best solution. Notwithstanding,'IP has reviewed the applicable plant procedures and confirmed that they provide adequate direction to the operators to ensure that gate valves 1B21-F065A and B are closed in a timely manner when the feedwater system becomes unavailable.

Further, operations personnel will be briefed to enhance their awareness of this concern and ensure compliance with the current procedural requirements.

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U-601784 t

In support of this exemption request,. additional-details and justification (including a Basis for No -

Significant Hazards Determination),.and marked-up pages from the CPS Operating License and Technical Specifications are provided in Attachment 2. In addition, an affidavit supporting the facts set forth in this letter and its attachments is provided as Attachment 1.

IP has reviewed this request against the criteria cf '

10CFR51.22 for categorical exclusion.from environmental impact considerations. This request.does not involve a significant hazards consideration, or significantly increase the amounts or change the types of effluents-  ;

that may be released offsite, nor would it_significantly increase individual or cumulative occupational radiation exposures. Based on the foregoing, IP concludes that this request meets the criteria given in 10CFR51.22(c)(9) .

for a categorical-exclusion from the r6quirement for an s Environmental Impact Statement.

Please note that approval of this' request is required for stortup from the second refueling outage which is currently scheduled to begin February 11, 1991. 7 Therefore, this application is being requested to be reviewed on an exigent basis. Justification and,a j description of the exigent circumstances, including why ,

the exigency could not be avoided, is provided in Attachment 2 to this letter. This request has Loen reviewed by the CPS Facility Review Group and Nuclear Review and Audit Group.

Sincer- ours, 1

S. . Perry Vice President DAS/alh Attachments cc: NRC Clinton Licensing Project Mana:jer .

NRC Resident Office i

NRC Region III, Regional Administrator Illinois Department of Nuclear Safety

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1 STATE OF ILLINOIS COUNTY OF DEWITT J. Stephen Perry, being first duly sworn, deposes and says: That he is Vice President of Illinois Power Company; that-the application exemption from the requirements of 100FR$0 Appendix J and for. -

amendment of Facility Operating License NPF 62 has been prepared-under his supervision and direction;;that he knows the contents thereof; and that to the best of his knowledge and belief said application and the facts contained therein are true and correct.

DATE: This If day of January-1991 hNdYhQ Signed:  ;

,'SthphenParry y

Subscribed and sworn to before me this A day of January 1991,  !

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Notarf Public i

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f  ? OFFICIAL SEAL" '4 Sharon E. Harna i 4 4 Notary Public, State of Ilknots - Q  ;

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My Commission Expires 3/9/91 _>l . '

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Attachment 2-t (Technical Specification Change Request No..LS 91 001) i 1

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) Itackcround and Der:eriotten of Proposed ChnnetA In accordance with 10CrR$0 Appendix J paragraph III.C.3 and Clinton Power Station (CPS) Technical Specification 3.6.1.2, " Primary Containment Leakago,* item b, the combined leakage rate of all containment penetrations and valves subject to Type B and C tests shall be less than 0.60 La when pressurized to Pa (9.0 pounds per square inch gua6e (psi& )). In accordance with Technical Specification 3.6.1.2, item d, the combined leakage rate of all

! secondary containment bypass leakage paths shall be less than 0.08 La when pressurized to Pa. Accordingly, the lenhage rates for feedwacer l system containment penetrations 1MC 009 and 1MC 010 are required to be included in these summations.

As-identified in CPS Updated Safety Analysis Report (USAR) Section 6.2.4.3.2.1.1.1, the feedwater lines are part of the reactor coolant pressure boundary. The two feedwater lines each incorporate three isolation valves. The isolation valve inside the drywell is a simple check valve (1B21 r010A(B)) incorporating a soft seat and is located ,

as close as practicable to the drywell wall. Outside the containment >

is an air assisted check valve [1B21 r032A(B).) incorporating a hard

. seat and is located as close as practicable to the containment wall.

Farther away from the containment is a remotely controlled motor-operated Sate valve (1B21 F065A(B)). In the event of a break in the feedwater line outside containment, the check valves would close to prevent any significant loss of reactor coolant inventory and thus provide prompt containment isolation. The IB21 F032A(B) check valve is " power assisted" to close and receives an automatic closure signal.

from the protection (containment and reactor vessel isolation control) system. In the event of a loss of coolant accident (IDCA),

it is important to maintain the availability of all reactor coolant makeup sources. For this reason, valve 1B21 F065A(B) is not designed-to close in response to an automatic containment isolation signal, llowever, this valve may be remotely closed from the control room thus ensuring long term containment isolation when the operator determines that continued makeup from the feedwater system is unnecessary. The NRC's acceptance of the design.of the isolation provisions for the i feedwater lines is specifically discussed in Section 6.2.4 of Supplement 2 to the NRC's Safety Evaluation Report for CPS (NUREG-

. 0853).

, As described in the cover letter of this submittal, CPS previously determined the maximum pathway leakage for each of these penetrations an accordance with Note 24 to CPS USAR Table 6.2 47 such that the Icakage rate for each feedwater penetration was equal to the leakage rate of the valve with the second smallest leakage rate. This maximum pathway leakage was included in the combined leakage rate of containment penetrations and valves subject to Type B and C tests and

, in the combined Icakage rate of secondary containment bypass leakage paths. Illstorically, the leakage rates of valves 1B21 F010A and B and 1B21 F065A and B have been much lower than that of valves 1B21 T032A ated B. As a result, the maximum pathway leakage for these penetrations did not include leakage from valves-1821 F032A and B.

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lU.601784 LS-91 001

. Page 2 of 11 I Based on discussions with the.NRC Staff on January 8.--1991, it was 1~ determined that the anximum pathway leakage for each of these '

penetrations must.be based on the leakage rate of the shtch valve

with the highest leakage rate (i.e., exclusive of the leakageirate j associated with the remotely controlled, motor operated gate valves .

i 1B21.F065A and B). This position would require that the leakage rate through valves IB21.F032A and B be used as the maximum pathway

• 1eakage for these penetrations and thus be included in-the above -4 combined leakage rates.

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Including-the-leakage rates for the 1821.F032A and-B valves.in the- 1 J combined leakage rates vould, at this time, cause the. combined leakage rate of containment penetrations and valves subject to Type B- +

and C tests to exceed the limits of 10CFR50 Appendix-J-- and CPS .,

Technical Specification 3.6.1.2.- The combined leakage rate of '

! secondary containment bypass leakage paths would also exceed the-  ;

limits of Technical Specification 3.6.1.2. Therefore,-IP is .;

requesting a one time exemption from 10CFR50 Appendix J and Technical-Specification 3.6.1.2 to allow the air leakage rate of valves 1B21 1 F032A and B to be excluded from the above combined leakage rates for the third operating cycle.

i in support of this request. marked up pages from the CPS Operating. .  ;

License and Technical Specifications are included in;this Attachment.

(The indicated Operating License changes are :only recommended changen -

as the primary intent would be to incorporate references to-the 100FR50' Appendix J exemption'where appropriate.)L Justification for this request, and an evaluation of its impact on the pertinent USAR-analyses, is presented below.

Justification for Proposed Chances The three transient / design basis accident analyses that are >

potentia 11y' impacted by this request consist of the faedwater line break outside containment event described in CPS USAR Section 15.6.6, the-feedwater line break inside containment event described in CPS m USAR Section 6.2.1.2, and the design basis accident recircult. tion i line. break described in CPS USAR Sections 6.2.1.1.3.3-and-15.6,5.

Containment / system isolation provisions with respect to the foodwater lines are discussed below for each of these ~ events..

I. Feedwnter Line Break Outside Containment

-As described in USAR Section 15.6.'6, the feedwater line break '

for this event is atsumed to be instantaneous, circumferential',

and downstream of- 1B21.F065A(B). relative, to the containment.

-The two check valves'in the.feedwater line:are assumed to-terminate' reactor coolant. flow out of the' break, Initiation of ,

the emergency core cooling' systems (ECCS) maintains the reactor water level above the low. low low level l' trip _and eventually i restores it to the normal elevation.. As a result, the fuel-is- ,

I covered throughout the event and therbtare-no pressure'ory ,l temperature transients sufficient to cause fuel' damage. l

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. o-13 91 001 e Page 3 of 11 Testing of valves 1B21.F032A and B during the current refueling .

outage has demonstrated the ability of these valves to close under reverse water flow conditions. Additionally, these valves have successfully passed a 1000 psig water leakage test performed as required by Section XI of the ASME Code.

Therefore, IP believes that the capability of these valves to check flow and function as reactor coolant pressure boundary isolation valves has been satisfactorily demonstrated.

Based on the above, both check valves [1B21.F010A(B) and 1B21 F032A(B)] in each of the feedwater lines vould be available to check reactor coolant flow out of the break. This is consistent with the USAR analysis and provides isolation capability even in the event of a single failure. Since, the analysis demonstrates that.no fuel damage occurs as a result of this event, any resultant offsite dose would be solely due to the amount of reactor coolant which is released from the break and would not be a function of containment leakage. Therefore, the air leakage of valves 1B21-F032A and B has na impact on the plant response or offsite dose consequences associated with this event.

II. Recirculation Line Break As described in USAR Sections 6.2.1.1.3.3.1 and 15,6.5, the postulated instantaneous guillotine rupture of a reactor recirculation line produces the highest peak containment t pressure and offsite dose consequences.

Prior to the postulated recirculation line break, the feedwater system would be in service providing the normal water supply to the reactor vessel. Following the postulated break, feedwater flow would continue as the steam driven feedwater pumps coast down. The steam supply for the steam driven feedwater pumps is provided from the main steam equalizing header which is-downstream of the main steam isolation valves-(MSIVs) relative to the containment. The MSIVs will receive an isolation signal l as a result of the postulated recirculation line break, terminating the steam supply to the steam driven feedwater pumps. If the motor driven feedwater pump 11s in service prior to the postulated recirculation line break, then it would normally remain in service and aid the ECCS in restoring

reactor vessel level, llowever, since the electrical supply to

! the motor driven feedwater pump is not safety related, no credit for its operation was assumed for reactor vessel makeup.

! With the motor driven feedvater pump in service, the feedwater check valves would remain open and the feedwater flow would

, prevent the escape of containment atmosphere through the associated containment penetration. :

In the event chat continued makeup from the feedwater source is not required, the operator would secure the' feedwater system and remotely close valves IB21.F065A and B from the control room. IP has reviewed the applicable plant procedures and

• confirmed that they provide adequate direction to the operators to ensure that valves IB21 F06SA and B are closed in a timely l manner when the feedwater system becomes unavailable. I n -- ,

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- ' U 601784 LS 91 001 o Page 4 of 11 addition, operations shift personnel will be briefed to enhance {

their awareness of this concern and ensure compliance with the i current procedural requirements.

With respect to containment air leakage through the feedwater penetrations, adequate short term isolation would be effected j by check valves 1B21 F010A and B when containrcent pressure is j in excess of the pressure in the feedwater lines (i.e. , when containraent atmosphere leakage could occur). Each of these  ;

check valves has successfully passed Type C testing with air at  !

a pressure of 9.0 paig (Pa). Closure of valves 1B21 F065A and B provides assurance of long term containment isolation.

Valves 1B21 F065A and B have also successfully passed Type C  !

testing with air at 9.0 psig.

With respect to the concern for immediate or short term containment isolation, IP also performed a realistic yet conservative evaluation of the potential for establishing a containment atmosphere leakage pathway to the environment through the feedwater containment penetrations. To support this evaluation, an analysis was pc.rformed to determine the maximum feedwater inventory depletion during reacter vessel blowdown. As it may be assumed that the feedwater system piping would be filled with water prior to the recirculation line break, th'is analysis demonstrated that only approximately 41% of the feedwater inventory that would be subject to the effects of the reactor vessel blowdown would be depleted primarily due tc flashing.

With respect to the potential leakage pathway, any containtrent atmosphere leakage through the feedwater system containment penetrations would be confined to the feedwater system piping.

Although the feedwater system piping is not specifically designed to withstand the effects of a seismic event, this piping is designed to the requirements of ANSI B31.1. Studies performed for the BWR Owners' Croup MSIV Leakage Closure j Committee, for example, have shown that piping designed to the requirements of ANSI B31.1 can reasonably be assumed to remain intact during a seismic event. The feedwater' system piping contains a number of elevation changes between the main steam tunnel and the feedwater heaters so that the system therefore contains a number of water traps. In addition to these water traps, the feedwater becomes more subcooled, such that ,

feedwater inventory depletion due to flashing is reduced, further into the feedwater delivery system. Following the reactor vessel blowdown and flashing of the water in the feedwater system, the remaining water in the feedwater system piping would be subjected to the post-LOCA containment pressure. The feedwater system piping elevation changes and components in the feedwater system will act to reduce the positive pressure seen by the water in the feedwater system piping. In addition, another check valve exists in the feedwater line at the discharge of the feedwater pu.ap. These features ensure that a water seal would be maintained in the feedwater system piping for a' considerable period of time, i.e., much longer than the period of time before operator-action is taken to close valves IB21 F065A and B. Therefore, l

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IP has concluded that.-realistically, a pathway for the a

containment atmosphere to the main condenser (and then to the t environment) would not be' established. ,

III. Feedwater Line Break inside Containment-As described in USAR Section 6.2.1.2, analysis of the feedwater.

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line break inside containment.was performed primarily to verify. f that containment-subcompartments do not experience unacceptable-pressure loadings._ The-feedwater line break was assumed _to bo jl an instentaneous guillotine rupture of the feedwater line'in ]

the annular space between-the reactor pressure vessel and the' 1 biological shield wall. .As described-in-USAR Section 6.2.1.2.1.2.2, the pressurization effects of the postulated feedwater line break inside containment are.much less _

pronounced than for the reactor recirculation line break. -As )

determined in the recirculation line break analysis above, 1 there is sufficient water volume and piping elevation changes within the feedwater system to ensure that a water seal vould-remain in this line for:a considerable period of time, even when the volume of water that would normally exist between the reactor vessel and the feedwater line break is excluded.

It should also be nottd that.the leakage rate testing requirements for the feedwater penetrations _at CPS are uniqua with respect to the other BWR/6 planta. The containment isolation provisions for the

feedwater lines of the other BWR/6 plants incorporate a leakage '

control system to provide long term leakage control for these L penetrations. Per 10CFR50 Appendix J 'the leakage rates through >

containment penetrations which incorporate seal systems are not required to be included in the combined leakage rate-ofJcontainment .!

penetrations and valves subject to Type B and C testi.. As a result, _  !

the other BWR/6' plants are not required-to, include the leakage rate (

of check valves IB21.F010A(B) and 1B21.F032A(B) in the combined ,

leakage rates. However, it should be noted that these leakage __ J control systems are manually initiated after remotely closing valves 3 l

1B21 F065A and B. Therefore, these plants incorporate the-same-short term containment isolation provisions as CPS.- )

Basis For No Sienificant llazards Considerarion According to 100FR50.92, a proposed change;to the Operating-1.icense i

involves no significant hazards-considerations'if operation of the- ,

facility . in .accordance with the proposed change would:not: (1)- ,

involve a significant increase.in the probability or the consequences.

of any accident previously evaluated, or (2) create the possibility of a new or different kind of-accident from any accident previously '

l evaluated, or (3) involve a significant_ reduction in a margin of 3 safety. This request is evaluated against each of these'eriteria below_ .i (1)- As discussed above, containment isolation. valves'1B21aF010A and:

B and 1B21 F065A and B have demonstrated acceptable air leakage:  ;

In addition, IP has_ determined that. on at.~1 east an--

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rates. 'l interim basis,.the design of the fendwater system piping provides adequate assurance that=an air leakage pathway fromi ,

the containment to the environment.would not exist even in the t

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event of a failure to itolate these penetrations. Based on

this determination, there is no impact on the applicable

accident analyses presented in the USAR and this request will not result in a significant increast in offsite t.oses. In

addition, this request does not involve a change to the plant design. Therefore, this request does not result in an increase in the probability of occurrence.of any event previously -

evaluated. ,

(2) This request does not involve a change to the plant design.

However, plant operation in accordance with the proposed

exemption would constitute a change to operation relative to the testing requirements of 10CFR50 Appendix J. 1p has deteriined that this change to operation has the potential to impact only the consequences of loss of coolant accident (s) which was previously discussed in item 1 above. Leakage or failure of the 1B21.F032A and B check valves cannot alone create a new or different accident _from any accident previously ,

evaluated.

(3) As discussed above, this request only impacts the requirement to include the air Icakage test results of check valves 1B21-F032A and B in the combined leakage rate of containment penetrations and valves subject to Type B and C tests, and in ,

the combined Icakage rate of secondary containment bypass-leakage paths. Therefore,_the only margin of safety that could be impacted by this request is the margin concerning the offsite dose consequonees of a design basis LOCA and the associated regulatory offsite dose limits. The ability to-maintain a water seal in the feedwater system piping outside containment together with the demonstrated _ acceptable air leakage rates of valves 1B21 T010A and B and 1B21.F065A and B provides cdequate assurance, on at Icast an interim basis, that the capability to prevent containment atmosphere leakage to the environment during a design basis LOCA vill be maintained. As a result, IP has concluded that this request does not introduce the possibility of a significant increase in offsite doses during a design basis' accident._ Therefore, this request does not result in a significant reduction in the. margin of safety.

l Based upon the foregoing, IP concludes that this request-does not j involve a significant hazards consideration.

Additionn1 Information In accordance with 100FR$0.12, granting'anicxemption from the j requirements of 10CFR$0 involves considering and balancing the  !

l factors listed in 10CFR50.12(b). In additiori, these-include (1) whether conduct of the proposed activities (in accordance with the q proposed exemption) will give rise to a significant adverse impact on:  !

the environment and the: nature _and extent of such impact, .if any;_(2) whether redress of any adverse environment impact from conduct of the proposed activities can reasonably be_offected should such redress be t necessary; (3) whether conduct of the proposed activities _would-foreclose subsequent' adoption _of niternatives; and (4) the effect of delay in. conducting such activities on the public interest, including the power needs to be used by the proposed facility, the availability .

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LS.91 001 i l . Page 7 of 11-  ?

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l of alternative sources, if any, to meet those needs on a timely basis'  !

, and delay costs to the applicant and to consumers. .

I l Based upon the ability to maintain a water seal in the feedwater l system piping outside containment', this request does not  ;

significantly change the type:or amount of effluents that may be i i released offsite. In. addition, there is nolsignificant increase in _.

individual or cumulative occupational radiation exposure.- Therefore, a 3' IP concludes that;this request will'not give rise to a_significant; j adverse impact on the environment. }

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, - 1 j Alternative solutions considered in lieu of this requested exeroption-. [

all include modification of the current design. As identified in the-

"l cover letter of this request, the design of these check valves makes 4 it extremely difficult to achieve _and maintain acceptable air leakageL ,

rates. (These valves have successfully passed a'1000 psig water leak. i rate test.) Industry and CPS experience with tilting disk check

i. valves has shown that this type of_ valve:is not suitable for air, leak j tightness. 1P has performed extensivo rework of these valves during

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l the current refueling outage. These rework activities have included- .

J valvo disassembly, relapping the_ disks and seats', acceptable bluen j checkir:g of the disks and . seats, _ verification that bushing clearances are within design tolerances, and replacing the air _ operator:

i- solenoids. Despite this rework. IP has been unable to achieve -

acceptable air leakage results. -IP believes that'a more; permanent j_ and effective-solution, which would likely involve changes to the

! current design, is required to ensure acceptable and_lastingL l- performance of these valves with respect to air leakage,_

i With respect to the effect of. disapproving or delaying approval of ,

this request, timely approval'is required to-permit CPS to resume operation in accordance with the current _ refueling, outage schedulo. .

i Approval of'this request would provide the time required for IP'to o svaluate the various alternatives:and adopt the=best solution. All-of these alternatives require time to. evaluate. and then, once a'

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solution is identified,-develop the-design package (s),; procure; "

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materials, and install. Denial'of-this request would likely result-

in a prolonged and costly extension of..the current refueling outage 9 with no significant benefit to safety.

j As previously identified, IP is requesting that this application be f reviewed on an exigent basis. The technical requirements for i determining the maximum pathway leakage of penetrations are not-specifically addressed in 10CFR50 Appendix J or the CPS Technical .

Specifications. Prior to discussion with the,NRC Staff on January 8, I 1991, IP believed that CPS was in full compliance with the requirements of 100FR50 ' Appendix'_J and the CPS Technica1L l Specifications, with respect to the leakageL requirements for _the feedwater system containment penetrations. -Therefore, the current exigent circumstances were unforeseeable.; In consideration. that this issuewasidentified'nearthe_ completion lof.the.currentrefueling:

outage. and that its rePolution requires adequate tiine to evaluate and .

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adopt-the best solution, prompt approval of the requested exemption; l

to 10CFR50' Appendix J-and proposed amendment to the CPS Technical >

Specifications is required to allow resumption of operation of CPS;

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