ML20238A676

Application for Amend to License NPF-3,revising Tech Spec Section 3/4.6.3, Containment Isolation Valves. Safety Evaluation Encl

ML20238A676
Person / Time
Site:	Davis Besse
Issue date:	08/31/1987
From:	Shelton D TOLEDO EDISON CO.
To:
Shared Package
ML20238A655	List: ML20238A651 ML20238A676 ML20238A688
References
NUDOCS 8709090384
Download: ML20238A676 (10)

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s-Dockst No. 50-346 License No. NPF-3 Serial No. 1415 Enclosure Page 1 APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER STATION UNIT NO. 1 Attached are requested changes to the Davis-Besse Nuclear Power Station.

Unit No. 1 Facility Operating License No. NPF-3. Also included are the Safety Evaluation and Significant Hazards Consideration.

The proposed changes (submitted under cover letter Serial No. 1415) concern:

Section 3/4.6.3, Containment Isolation Valves, Specification 3.6.3.1; and Section 3/4.6.3, Containment Isolation Valves, ble 3.6-2.

By ~

D. C. Shelton, Vice President, Nuclear Sworn to and subscribed before me this 31st day of August, 1987.

b) ALD $

Notary Public, State of Ohio k.

My commissien expires ( /8 /

9709090384 PDR ADOCK hhhf146 ppg

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Dockat.No. 50-346

License No. NPF-3

'Scrial No. 1415 Enclosure t? Page 2

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The following information is provided to support issuance of the requested changes to the Davis-Besse Nuclear Power Station, Unit No. 1 Operating License No. NPF-3, Appendix A, Technical Specification 3.6.3.1 and Table 3.6-2.

A. Time Required to Implement: This change is to be implemented within 30 days after NRC issuance of the License Amendment.

B. Reason for Change (Facility Change Request No. 87-0115): This change was committed to in Toledo Edison's response to~ Inspection Report 86-032 (Serial No. 1-722, dated April 13, 1987).

C. Safety Evaluation: See attached Safety Evaluation (Attachment 1).

D. Significant Hazards Consideration: See attached Significant Hazards Consideration (Attachment 2).

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Dockot No. 50-346

-License No. NPF-3 Serial No. 1415 Attachment 1 Page 1 SAFETY EVALUATION INTRODUCTION The purpose of.this License Amendment request is to revise the Davis-Besse Nuclear Power Station, Unit No. 1 Operating License, Appendix A, Technical Specification (TS) Section 3/4.6.3, Containment Isolation Valves. Specifically, this request proposes the following

. changes to this section:

1). Add the following ACTION statement to Technical Specification 3.6.3.1:

"e. The provisions of Specification 3.0.4 are not applicable provided the affected penetration is isolated."

2) Add a clarifying footnote to Technical Specification 3/4.6.3.1:

"* Isolation of penetrations / valves may impact the OPERABILITY of affected systems. Appropriate ACTIONS and the OPERABILITY of these systems will be governed by the applicable Limiting Conditions for Operation."

3) Revise Table 3.6-2, Containment Isolation Valves, by deleting the exception to TS 3.0.4 for Containment Purge and Exhaust Isolation Valves.

SYSTEMS AFFECTED Containment Isolation Systems DOCUMENTS AFFECTED Technical Specification Section 3/4.6.3 and Table 3.6-2.

REFERENCES i

Generic Letter 87-09 " Sections 3.0 and 4.0 of the Standard Technical ,

Specifications (STS) on the applicability of Limiting Conditions for Operation and Surveillance Requirements. (June 4, 1987)"

SAFETY FUNCTIONS OF SYSTEMS AFFCCTED The safety function of the containment isolation systems is to minimize radiation releases to the environment during postulated accident  !

conditions so that offsite doses are below 10CFR100 guideline values.  !

The safety function of the containment isolation valves is to isolate L

those containment penetrations which are not required to open or remain open to mitigate the consequences of an accident. This ensures that the containment will be isolated in the event of a radiation release to the containment or pressuriention of the containment thereby preventing potential radiation releases to the environment.

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. s 6i , .Do'ckst No.150-346 l 4

License No. NPF-3 j Serial ~No..1415- l

, Attachments 1  !

Page'2 < l n ,

1 AMENDMENT REQUEST DISCUSSION l E Technical. Specification 3.0.4 prohibits entry'into a higher OPERATIONAL MODE unles's=the conditions of the Limiting Condition for Operation (LCO)  !

Jare' met without reliance on the provisions'of ACTION statements. As L stated.'in the-Bases section for TS 3.0.4'"The intent of this. specification i .is to' insure that facility' operation is not initiated with either required equipment or systems inoperable or other specified limits being exceeded."

This. ensures that when the plant.is ready to change to a higher MODE of operation all the required equipment is OPERABLE.

If the' plant'is" operating and an LCO is not met, the ACTION statements specify the length of time the plant can operate in that OPERATIONAL MODE with inoperable. equipment. In some instances continued pover operation 1

Isipermitted for an unlimited period of time provided the remedial actions specified in the ACTION requirements are satisfied. .InLthese instances if the plant-is in a shutdown condition, Specification 3.0.4 prevents-changing to a higher operational mode until the inoperable equipment.or system is restored to OPERABLE condition unless an exemp-l ' tion to TS 3.0.4 is'noted.

In-Technical Specification 3.6.3.1 the LCO states that "The containment isolation valvesLspecified in Table 3.6-2 shall be OPERABLE with isolation times shown:in Table 3.6-2". The ACTION requirements for TS 3.6.3.1 permit continued operation of the plant for an unlimited period of time.with inoperable containment isolation valves, as long as the affected containment penetrations are isolated and kept isolated. Since TS.3.6.3.1 currently does not contain an exception to TS 3.0.4, except for a very few' valves, if the plant is shutdown it can not be returned to power operation until the inoperable containment isolation valves are restored to an OPERABLE condition. Although it is not a normal practice to start the plant with a required containment isolation valve inoperable, it is considered that this restriction on OPERATIONAL MODE change is unnecessary when the compliance with ACTION statement requirements permit continued power operation for an unlimited period of time. In this instance, compliance with ACTION statement requirements provides an acceptable level of safety for continued operation without regard to the equipment status before or after a NODE change.-

Based on the above it is proposed that ACTION statement "e" be added to TS 3.6.3.1.- This ACTION statement "e" states that "The provisions of Specification 3.0.4 are not applicable provided the affected penetration is' isolated." This propoced change would' permit plant startup with any of the containment isolation valves listed in Table 3.6-2' inoperable as long as ' the other ACTION requirements of TS 3.6.3.1 are satisfied and this action does not-impact,the safety functions of required systems.

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Yor the purposes of containment 1 solation function, the isolated position

.is the safe position for'an inoperable containment isolation valve and the associated containment penetration. However, certain containment

Docket No. 50-346 License No. NPF-3 Serial No. 1415 Attachment 1 Page 3 isolation valves are required to open following an accident to mitigate the consequences of that accident (e.g., High Pressure Injection line valves).

Securing the valves in the required safety related systems in a closed position would impact the use of those systems. The OPERABILITY of those systems with containment isolation valves secured in a closed position will be governed by the LCOs for those systems. ,

Since the isolation of a containment isolation valve may impact the use of a system, a footnote to TS 3.6.3.1 is added to caution the user to refer to the LCOs for the affected systems. This footnote states that

" Isolation of penetrations / valves may impact the OPERABILITY of affected systems. Appropriate ACTIONS and the OPERABILITY of these systems will be governed by the applicable Limiting Conditions for Operation."

Since TS 3.6.3.1 as revised would permit MODE changes with an inoperable containment isolation valve, provided the affected penetration is isolated per ACTION requirements, exceptiono to TS 3.0.4 for individual containment isolation valves or containment penetrations are not required in Table 3.6-2. In the existing Table 3.6-2, this exception is applied to penetrations 33 and 34, for the Containment Purge and Exhaust Isolation Valves. This specific exception to TS 3.0.4 for Containment Purge and Exhaust Isolation Valves in Section B of Table 3.6-2 is no longer required and is being deleted.

UNREVIEWED SAFETY QUESTION EVALUATION The proposed changes do not increase the probability of occurrence or the consequences of an accident or a malfunction of an equipment important to safety previously evaluated in the Updated Safety Analysis Report (USAR). The proposed changes do not involve a modification to any plant system. It is shown above that the proposed changes to TS 3/4.6.3 will not adversely affect plant safety and the containment isolation safety function. If the safety functicn of systems that are required to mitigate the consequences of an accident is affected, the applicable LCO for that system will be applied and plant operations will be maintained within the requirements of the Technical Specifications. If it is not permissible (due to another LCO), feasible or practical to isolate the affected pene-tration, plant startup will not be permitted (100FR50.59(a)(2)(1)) .

The proposed changes do not create a possibility for an accident or a malfunction of a different type than any previously evaluated in the USAR.

Tta proposed changes do not involve a modification to any plant system.

It is shown above that the proposed changes to TS 3/4.6.3 will not adversely affect plant safety and affect the containment isolation safety functic ns . Currently, power operation is permitted for an indefinite period as long as the affected penetration (s) are isolated. The affected penetration (s) will be isolated only when its use is not required for safe operation of the plant. If the safety function of systems that are required mitigate the consequences of tn accident is affected, the

f l Dockat No. 50-346 l- License No. NPF-3 I

Serial No. 1415 Attachment 1 Page 4 applicable LCO for that system will be applied and plant operations will be maintained within the requirements of the Technical Specifications.

If it is not permissible (due to another LCO), feasible or practical to isolate the affected penetration, plant startup will not be permitted since-provisions of. Specification 3.0.4 will then be applicable (10CFR50,59 (a) (2) (ii)) . i The proposed changes do not reduce the margin of. safety as defined in the basis for any Technical Specification because the affected penetrations sould be isolated per ACTION statement requirements thereby facilitating containment isolation without regard to the required response time of the affected isolation valve or any assumptions of such isolation in the USAR (10CFR50.59(a)(2)(iii)) .

CONCLUSION Pursuant to the above, it is concluded that the proposed changes to TS 3/4.6.3 and Table 3.6-2 do not involve any unreviewed safety questions.

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, m Docket No. 50-346 License No. NPF-3 Serial No. 1415 Attachment 2 Page 1 l SIGNIFICANT HAZARDS CONSIDERATION INTRODUCTION

-p' The purpose of this License Amendment Reouest is to revise the I Davis-Besse Nuclear Power Station, Unit No. 1 Operating License, Appendix A, Technical Specification (TS) Section 3/4.6.3, Containment Isolation Valves. Specifically, this request proposes the following changes to this section:

a. Add the following ACTION statement to Technical Specif' cation '*

3.6.3.1:

"e. The provisions of Specification 3.0.4 are not applicable provided the affected penetration is isolated."

b. Add a clarifying footnote to Technical Specification 3/4.6.3.1:

"* Isolation of penetrations / valves may impact the OPERABILITY of affected systems. Appropriate ACTIONS and the OPERABILITY of these systems will be governed by the applicable Limiting Conditions for Operation."

c. Revise Table 3.6-2, Containment Isolation Valves, by deleting the exception to TS 3.0.4 for Containment Purge and Exhaust Isolation Valves.

SYSTEMS AFFECTED Containment Isolation Systems

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DOCUMENTS AFFECTED Technical Specification Section 3/4.6.3 and Table 3.6-2. ..

4 REFERENCES

1. Generic Letter 87-09 " Sections 3.0 and 4.0 of the Standard Technical Specification (STS) on the applicability of Limiting Conditions for ~

Operation and Surveillance Requirements. (June 4, 1987)"

SAFETY FUNCTIONS OF SYSTEMS AFFECTED The safety function of the containment isolation systems is to minimize radiation releases to the environment during postulated accident conditions so thac offsite doses are below 10CFR100 guideline values.

The safety function of the containment isolation valves is to isolate those containment penetrations which are not required to open or rcmain

open to mitigate the consequences of an accident. This ensures that the containment will be isolated in the event of a radiacion release to the ,,

containment or pressurization of the containment thereby preventing potential radiation releases to the environment.

i .

I Docket No. 50-346 License No. NPF-3 Serial No. 1415 Attachment 2 Page 2 AMENDMENT REQUEST DISCUSSION Technical Specification 3.0.4 prohibits entry into a higher OPERATIONAL 1 MODE unless the conditions of the Limiting Condition for Operation (LCO) are met without reliance on the provisions of ACTION statements. Ac stated in the Bases section for TS 3.0.4 "The intent of this specification is to insure that facility operation is not initiated with either required equipment or systems inoperable or other specified limits being exceeded."

This ensures thet when the plant is ready to change to a higher MODE of operation all the required equipment is OPERABLE.

If the plant is operating and an LCO is not met, the ACTION statements I specify the length of time the plant can operate in that OPERATIONAL MODE with inoperable equipment. In some instances continued power operation is permitted for an unlimited period of time provided the remedial actions specified in the ACTION requirements are satisfied. In these instances, if the plant is in a shutdown condition, Specification 3.0.4 prevents changing to a higher operational mode until the inoperable equipment or system is restored to OPERABLE condition unless en exemption to TS 3.0.4 is noted.

In Technical Specification 3.6.3.1 the LCO states that "The containment isolation valves specified in Table 3.6-2 shall be OPERABLE with isolation times shown in Table 3.6-2". The ACTION requirements for TS 3.6.3.1 permit continued operation of the plant for an unlimited period of time with inoperable containment isolation valves, as long as the affected containment penetrations are isolated and kept isolated. Since TS 3.6.3.1 currently does not contain an exception to TS 3.0.4, except for a very few valves, if the plant is shutdown it can not be returned to power operation until the inoperable containment isolation valves are restored to an OPER6BLE condition. Although it is not a normal practice to start the plant with a required containment isolation valve inoperable, it is considered that this restriction on OPERATIONAL MODE change is u1necessary when the compliance with ACTION statement requirements permit continued power operation for an unlimited period of time. In this instance, compliance with ACTION statement requirements provides an acceptable level of safety for continued operation without regard to the equipment status before or after a MODE change.

Based on the above it is proposed that ACTION statement "e" be added to TS 3.6.3.1. This ACTION statement "e" states that "The provisions of Specification 3.0.4 are not applicable provided the affected penetration is isolated." This proposed change would permit plant startup with any of the containment isolation valves listed in Table 3.6-2 inoperable as long as the other ACTION requirements of TS 3.6.3.1 are satisfied and this action does not impact the safety functions of .equired systems.

For the purposes of containment isolation function, the isolated position is the safe position for an inoperable containment isolation valve and the associated containment penetration. However, certain containment

Docket No. 50-346 License No. NPF-3 Serial No. 1415 Attachment 2 Page 3 isolation valves are required to open following an accident to mitigate the consequences of that accident (e.g., High Pressure Injection line valves).

Securing the valves in the required safety related systems in a closed position would impact the use of those systems. The OPERABILITY of those systems with containment isolation valves secured in a closed position will be governed by the LCOs for those systems.

Since the isolation of a containment isolation valve may impact the use of a system, a footnote to TS 3.6.3.1 is added to caution the user to refer to the LCOs for the affected systems. This footnote states that

" Isolation of penetrations / valves may impact the OPERABILITY of affected systems. Appropriate ACTIONS and the OPERABILITY of these systems will be governed by the applicable Limiting Conditions for Operation."

Since TS 3.6.3.1 as revised would permit MODE changes with an inoperable containment isolation valve, provided the affected penetration is isointed per ACTION requirements, exceptions to TS 3.0.4 for individual containment isolation valves or containment penetrations are not required in Table 3.6-2. In the existing Table 3.6-2, this exception is applied to penetrations 33 and 34, for the Containment Purge and Exhaust Isolation Valves. This specific exception to TS 3.0.4 for Containment Purge and Exhaust Isolation Valves in Section B of Table 3.6-2 is no longer required and is being deleted. l SIGNIFICANT HAZARDS CONSIDERATION The proposed changes do not involve a significant hazards consideration because the opecation of the Davis-Besse Nuclear Power Station, Unit No. 1, in accordance with these changes would not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated because the proposed changes do not involve a modification to any plant system and will net adversely affect plant safety or the containment isolation safety function.

If the safety function of systems that are recuired to mitigate the  ;

consequences of an accident is affected, the applicable LCO for that system will be applied and plant operations will be maintained within the requirements of the Technical Spe:ifications (10CFR50.92 (c) (1)) . 4 1

2. Create the possibility of a new or different kind of accident from any accident previously evaluated because the proposed changes do not involve a modification to any plant system. Currently, power operation is permitted for an indefinite period as long as the affected penetrations are isolated. The affected penetrations will be isolated only when their uce is not required for safe operation of the plant. If the safety function of systems that are required to mitigate the consequences of an accident is affected, l the applicable LCO for that system will be applied and plant l operations will be maintained within the requirements of the Technical Specifications (10CFR50.92(c)(2)).

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l Dockst No. 50-346 License No. NPF-3 Serial No. 1415 Attaciunent 2 Page 4

3. Involve a significant reduction in a margin of safety because the affected penetrations would be isolated per ACTION statement requirements thereby facilitating containment isolation without regard to the required response time of the affected isolation valve or any assumptions of such isolation in the USAR (10CFR50.92(c)(3)).

CONCLUSION Cn the basis of the above, Toledo Edison has determined that the amendment request does not involve a significant hazards consideration.

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