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License Amend Request 91-010 to License NPF-87,changing TS to Incorporate Provisions of Generic Ltr 90-06, Resolution of Generic Issue 70, 'Porv & Block Valve Reliability' & Generic Issue 94, 'Addl Low Temp Overpressure....'
	ML20086E723
Person / Time
Site:	Comanche Peak
Issue date:	11/27/1991
From:	William Cahill; TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20086E728	List: ML20086E729; TXX-9142, License Amend Request 91-010 to License NPF-87,changing TS to Incorporate Provisions of Generic Ltr 90-06, Resolution of Generic Issue 70, 'Porv & Block Valve Reliability' & Generic Issue 94, 'Addl Low Temp Overpressure....';
References
	REF-GTECI-070, REF-GTECI-094, REF-GTECI-NI, TASK-070, TASK-094, TASK-70, TASK-94, TASK-OR GL-90-06, GL-90-6, TXX-91427, NUDOCS 9112020282
	Download: ML20086E723 (10)
	v • d • e

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$$ Log # TXX-91427 File # 916 (3/4.4.4)

Ref # GL 90-06 10CFR50.90 TUFlIC1RK: 10(IRh0*92 l wun.m J. c.hiii, J,.

D"" U ' I E Grvre Ys< r bessJent U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555

SUBJECT:

COMANDiE PEAK SlEAM E LECTRIC STATION (CPSES)-UNIT 1 DOCKET NO. 50-445 L ICENSE A!i[NDMENT REQUEST 91-010 REVIS!DN 10 lECHNICAL SPECIFICATION 3/4.4.4, 3/4.4.8.1 AND 3/4.4.8.3 Ref: 1) Generic Letter 90-06, Retalution of veneric !ssue 70,

" Power-Operated Relief Valve and Block Valve Reliability,"

and Generic issue 94, " Additional Low-lemperature Overpressure Protection for Light-Water Reactors," Pursuant to 10CFR50.54(f)

2) TU Electric letter logged TXX-901053, dated December 21, 1990, from W. J. Cahill Jr. to the NRC.

Gentlemen:

Pursuant to 10CFR50.90, TU Electric hereby requests an amendment of Appendix A to the CPSES Unit 1 Operating License (NPF-87) by incorporat ing the attached changes into the CPSES Unit 1 Technical Specif ications.

Based on technical studies for GI-70 (NUREG-1316) and Gl-04 (NUREG-1326), the staff requested that actions identified in Section 3 of Enclosures A and B to Generic Letter 90-06, (Reference 1) be taken by licensees in order to increase plant safety and reliability. TU Electric responded to this request in reference 2. This response committed to provide certain proposed Technical Specification changes for Unit 1 prior to the first refueling outage. The attached proposed changes to Technical Specifications 3/4.4.4, 3/4.4.8.1 and 3/4.4.8.3 satisfy that comihitment.

TU Electric has reviewed the proposed amendment pursuant to 10CFR50.92 and determined that it does not involve a significant hazards consideration. The Msis for this determination is provided in the attachments.

For administrative purposes, it is requested that the approval transmittal for this proposed amendment include a seven day implementation period following the date of issuance.

In accordance with 10CFR50.91(b), TU Electric is providing the State of Texas with a copy of this proposed amendment.

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TXX-91427 I Page 1 of 1 l If you should have any questions concerning this matter, please contact

?tr. J. L. Rodriquez at (214) 812-8323.

Sincerely, l '

/

William J. Cahill Jr. '

JDS/gj Attachments: 1. Af fidavit to TXX-91427

2. Proposed Technical Specification Changes (detailed description)

3. Revised Technical Specification Pages 4 Significant Hazards Evaluation

5. Environmental Assessment

.c - Mr. R. D. Martin, Region IV Resident inspectors, CPSES (2)

Mr. T. E. Bergman, NRR Mr. D. K. Lacker-Bureau of Radiation Control Texas Department of Public Health 1100 West 49th Street Austin, Texas 78704 File # 10035 clo 916 (3/4.4.8.3) clo .l

-905.2 clo 905.4 clo 907.6 clo 903.9 clo l

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Attachment 1 to 1XX-91427 Page 1 of 1 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMIS$10N In the matter of )

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Texas Utilities Electric Company ) Docl<et No. 50-445

)

(Comanche Peak Steam Electric )

Station, Unit 1) )

AFFIDAVIT-William J. Cahill, Jr. being duly sworn, hereby deposes and says that he is Group Vice President,. Nuclear of TU Electric, that he is duly authorized to sign and file with the Nuclear Regulatory Commission this transmittal of License Amendment Request 91-010; that he is familiar with the content thereof; and that the matters set forth therein are true and correct to the best of his knowledge, information and belief, t

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Wflliam J. CahiK1, Jr.

Group Vice President, Nuclear

! STATE OF TEXAS )

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LOUNTY OF SOMERVELL )

Subscribed and sworn to before me, a Notary Public, on this 27th day of Novemhejt ,, , 1991,

___ 4 Notary Public fI N ' PATRICIA Y!!LSON w ww.sa wns g Ql;{

Rg, Manh 16,1933 .n

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Attachment.2'to TYX-91427 Page'1 of 6 PROPOSED TECHNICAL SPECIFICATION CHANGES The proposed changes made to the. current.CPSES Technical Specifications incorporate TU Electric's response to the recommendations in Enclosure A and Enclosure B of Generic Letter 90-06 as described in letter logged TXX-901053 to resolve Generic issues 70 and 94 Changes to' improve clarity and accuracy of the Technical Specifications are also included.

CHANGES IN RESPONSE TO GL 90-06 Discussion The changes proposed for Technical Specification 3/4.4.4 represent the NRC-staff position resulting'from the resolutir of Generic Issue 70 " Power-Operated Relief Valve and Block Valve Re'-m 1 'y", to improve the reliability.

of PORVs and block valves.by revising ti - ]n statements to identify when the PORV block valves may Le C M, when ,.wer may be removed from the block valves and when PORVs may be shifted to manual control. Also, the surveillance was enhanced to assure operability when needed and to prohibit testing.when the valves should remain closed.

DESCRIPTION O LCHANGES AND JUSTlFICATIOR Technical-Specification 3/4.4.4 General:

Grammatical corrections made in several locations to reflect proper plurality (e.g., "their" to "its"; "PORV(s)" to "PORVs", etc.).

LCO 3.4.4:

The Limiting Condition for Operation statement is clarified by replacing "All" with "Both".

Justification:

l= This change is in accordance with Attachment A-1 of Generic Letter _90-06 and.the CPSES plant design. Both is more appropriate because the design includes only two PORVs.

l-Action (a.):

The action' statement is clarified by changing "more" to "both". The-statement "with power maintained to the block valve (s)" is added.

Justification:

Changes to Action (a.) are consistent with the guidance provided in ,

Attachment A-1 of Generic Letter 90-06. "Both is more appropriate because the CPSES design includes only two PORVs. Power is maintained to allow use of the PORVs to mitigate an overpressure event when seat leakage is the only problem.

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Attachment 2 to TXX-91427

- Page~2 of 6-Action (c.):

The action statement is clarified by changing "each of the PORV(s)" to "atLleast one PORV." '

Justification:

This change is consistent with the guidance provided in Generic Letter 90-06. The recommended Technical Specification changes provided in Attachment A-1 to the Generic Letter states that "within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months restore at least one PORV". The revised action statement allows thn licensee to exit action "c." if the operability of at least one PORV is restored within one hour. Action "b." would then become the effective action because one PORV would remain inoperable due to causes other than seat leakage. The revision clarifies the coordination between these actions statements. The requirements on the licensee remain the same.

Action.(d):

Again, "more" is changed to "both". The remainder of the action is changed.from closing and removing power from_the block valves to placing the PORV(s) in manual. The shutdown requirements ar? essentially unchanged.

-Justification:

This change allows a'PORV to be placed in manual control if its associated block valve'is inoperable. It will also require that at-least one block valve be' returned to operable status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months if both block valves are inoperable and provides a 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months allowed outage time for one inoperable block valve. Placing the PORVs in manual, in lieu of closing and removing power from the block valves, allows the PORVs to be used -for the control of RCS pressure while precluding .its automa :

. opening for an overpresrure-event and avoiding the potential for a stuck-open_PORV at a1 time when the block valve is inoperable.

Surveillance Requirement 4.4.4.2:

The appiicable ACTION is changed from "a or_b" ta "b or c".

Justification:

This change is consistent with the guidance provided in Attachment A-1 of Generic Letter 90-06. ACTION (a) has been deleted because the

-operability of the block valve is important if the block. valve is closed to isolate a PORV with-excessive seat leakage. _The opening of the block _

valve in-this case is necessary to permit the PORV to be used for manual control of.RCS pressure.

Action (c) has been added because the allowed outage time is very-short (13 hours1.50463e-4 days 0.00361 hours 2.149471e-5 weeks 4.9465e-6 months maximum) compared to the 92 day surveillance interval. The block valve (s) will be adequately tested upon restoration of the: PORV's operability.

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Attachment 2.to TXX-91427 )

-Page 3 of 6-Technical Specification 3'/4.4.8.1

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Surveillance Requirement 4.4.8.1.2:

_ Technical Specification Figure 3.4-4 is added to the listing of figures-

_to be updated based on_the results of the Reactor Pressure Vessel irradiation surveillance program.

Justification:

The change is made to emphasize the need to update the figure and the allowable PORV setpoint based on results of the Reactor Pressure Vessel _ 4 irradiation surveillance program. ,

Technical Specification 3.4.8.3 Discussion:

Generic' Issue 94, " Additional Low-Temperature Overpressure Protection for Light-Water Reactors" addresses concerns with the implementation of the resolution to Unresolved Safety Issue (USI) A-26, " Reactor Vessel Pressure Transient Protection (Overpressure Protection)". The resolution of USI A-26 involves several administrative actions to reduce the-potential for overpressure transients. These include, but are not limited to, minimizing the time the RCS is water-solid, restricting the number of high-pressure pumps operable below 350 Degrees F, minimizing the RCS to S/G temperature differential, and prosiding a PORV setpoint which varies _with RCS temperature. Despite these controis, l

low-temperature overpressure transients have continued to occur. The net

! effect of NUREG 1326, which provides the resolution to Generic Issue 94,

! 'is to limit the amuunt of time-for MODE 5 or 6 to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months that a plant can be in a~ condition conducive to an overpressure transient with only a

-single overpressure' mitigation device. operable. The proposed revisions

! to. Technical Specification 3/4.4.8.3 are being submitted to address this L portion of Generic Letter 90-06. In addition, these changes. allow the .

use ofLone RHR suction relief valve and one PORV as'an acceptable group of overpressure protection; devices.

Limiting Condition-for Operation 3.4.8.3:

TheLLCO statement is being modified to require that at least two overpressure protection devices be operable. Additionally, the guidance relating _toidepressurizing and venting of the RCS is being incorporated into the LC0 statement rather than-listing this guidance'as an-overpressure protection system. The use of one RHR suction relief valve and one PORV'was added as an_ acceptable group of overpressure protection devices.

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Attachment 2 to TXX-91427

Page 4 of 6--

! Justification:

Analyses show that either PORV or either RHR relief valve has sufficient capacity to prevent exceeding 10 CFR 50 Appendix G limits when the '

transient is-limited to either: (1) the start of an idle RCP with the secondary water temperature of_the steam generator less than or equal to 50 degrees F above the RCS cold leg temperatures, or (2) the start of two charging pumps and their injection into a water-solid RCS.

- Applicability:

P The MODE 6 applicability of this Technical Specification is changed to include "when the head is on tae reactor vessel."

Justification:

This change is consistent with the guidance provided in Generic Letter

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90-06. This change is to-improve clarity only. ;

l Action (a.):

l The phrase "in MODE 4", is added. The words are revised to discuss the j

two required overpressure protection devices in lieu of a PORV or RHR !

suction relief.

Justification:-

This change is consistent with the guidance provided in Generic Letter 90-06. '"In MODE 4" was added because a separate actions (see (b.)'below) is beingladded for_ MODES 5'and 6.

The words were revised to be-consistent with the phrasing in the LCO for clarity.

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Action (b.):

A new action.(bc) is added to reduce the allowed outage time-(A0T) for one of the two required PORV or RHR suction relief valve to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months in MODES 5.or 6. Also the inclusion of-the plant specific vent size,=and the use=of "within-the next 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months " instead of "within a total of 32 hours3.703704e-4 days 0.00889 hours 5.291005e-5 weeks 1.2176e-5 months ".

Justification:

'This new ACTION is consistent with the guidance-provided in Generic Letter 90-06.- The NRC hasEconsidered the conditions under which a low-temperature overpressure transient is niost likely to occur. While low-temperature. overpressure-protection is required for all shutdown MODES, the nost vulnerable period of time was found to be MODE 5- with the reactor coulant. temperature'less than or equal to 2000F, specifically __

when water solid. This evaluation is based on the detailed evaluation of operating reactor experiences performed in support of GI 94. The staff concluded that the low-temperature overpressure protection system -

performs a safety-related function, and-inoperable overpressure protection equipment should be restored to an operable status in a m-. , , . - , e m r_-r _,w . ,m. ~,,c.._ , - - - - , .m- , , , -, -. --,,,,--y- - , , _ - , ,, - _ -

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Attachment 2 to TXX-91427 Page 5 of 6 shorter period of time. The current 7-day A0T is considered by the_NRC to be too long under certain conditions. The NRC has concluded that_the A0T-should be reduced to 24-hours when operating in MODES 5 or 6 when the potential for an overpressure transient is-highest. The ACTION is worded and structured _to be consistent with the LCO and other action statements for clarity.

Acilon(c.):

This action was previously action (b.)L and has been renumbered. - The words have been revised to address overpressure protection devices and change the phrasing.

1 Justification:

The changes have been made to make-the ACTION consistent with the words and phrasing in the LCO and other ACTIONS for clarity.

-Action-(d.):

This ACTION has been added. This action requires confirmation of the vent path when the RCS is vented due to new ACTIONS a,'b or c.

Justification:

This.new action emphasizes the need to confirm the RCS vent path.

Although this verification is_already required per SURVEILLANCE 4.4.8.3.3, this new ACTION will immediately direct the operator to this surveillance if ACTION a, b or c are entered.

Action (e.):

This action was_previously ACTION _(c.) and has been renumbered only, Justification:-

Editorial-change-only. - - - -

-Action (f.):-

This_is a new ACTION which allows entry into-the applicable MODES when the--LCO is not met.

Justification:

This action was;not previously included in this Technical Specification-and'is being incorporated now to be: consistent with the Generic Letter.

The addition of this ACTION will. allow the entry into MODES wherelthe potential for any overpressure transient may be reduced (e.g... entry of

. MODE-4 from MODE 5).

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Attachment 2 to TXX-91427 Page 6 of 6 Bases 3/4.4.4, Eclief ValyeJi lhe Bases is revised to add details concerning the ability of the PORV's to provide pressure relief or pressure control during a steam generator tube rupture or for plant cooldown. The discussion of a steam bubble is also clarified.

Bases 3/4.4.8, Er_ enure / Temperature Limits The Bases is revised to reflect the acceptability of the use of one PORV and one RHR suction relief for LlOP mitigation as allowed by the revised LCO.

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. Attachment'3 to TXX-91427' .

Page 1 of 1

. TECHNICAL SPECIFICATION CHANGES.

COMANCHE PEAK STEAM ELECTRIC STATION UNIT 1 LIST OF AFFECTED DAGES 3/4 11 3/4 12 3/4 23 3/4 28 B3/4 2 B3/4 13-l L

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TXX-9142, License Amend Request 91-010 to License NPF-87,changing TS to Incorporate Provisions of Generic Ltr 90-06, Resolution of Generic Issue 70, 'Porv & Block Valve Reliability' & Generic Issue 94, 'Addl Low Temp Overpressure....'

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