ML20207P987

Forwards Application for Amend to License DPR-34,changing Tech Specs to Require Both evaporator-economizer Superheater Sections & Both Reheater Sections to Be Available During Operation at Power.Fee Paid

ML20207P987
Person / Time
Site:	Fort Saint Vrain
Issue date:	01/15/1987
From:	Robert Williams PUBLIC SERVICE CO. OF COLORADO
To:	Berkow H NRC OFFICE OF ADMINISTRATION (ADM), Office of Nuclear Reactor Regulation
Shared Package
ML20207P988	List: ML20207P987 ML20207P989 ML20207P991 ML20207P993
References
P-87002, TAC-63576, NUDOCS 8701210005
Download: ML20207P987 (5)

Text

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2420 W. 26th Avenue, Suite 1000, Denver, Colorado 80211 R.O. WILUAMS, JR.

ESINEn'es January 15, 1987 Fort St. Vrain Unit No. 1 P-87002 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Attention: Mr. H. N. Berkow, Director Standardization and Special Projects Directorate Docket No. 50-267

SUBJECT:

Proposed Technical Specification Change Eliminating Reliance on Reheater Section of the Steam Generator For Safe Shutdown Cooling

REFERENCE:

1) PSC Letter, Gahm to NRC, dated August 11,1986(P-86513)

2) PSC Letter, Gahm to NRC, dated October 17, 1986 (P-86587)

3) PSC Letter, Warembourg to Berkow, dated December 30, 1986 (P-86683)

4) PSC Letter, Warembourg to Berkow, dated December 30, 1986 (P-86682)

Dear Mr. Berkow:

This letter submits proposed changes to 'he Fort St. Vrain (FSV)

Technical Specifications to require both evaporator-economizer-h superheater (EES) sections and both reheater sections be available og@ during operation at power as the minimum number of operable heat

-o exchangers. The FSV Technical Specifications currently require both E the reheater section and the EES section of one steam generator and bO either the reheater section or the EES section of the other steam os generator be operable for the removal of decay heat. Each EES 80 section provides adequate capability for Safe Shutdown Cooling from OQ power levels up to 87.5 percent (see FSAR Sections 10.3.9 and N 14.4.2.2). However, ~a reheater section does not provide adequate o a: capability for Safe Shutdown Cooling at power levels above 39

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P-87002 Page 2 January 15, 1987 percent, and therefore PSC will no longer rely on reheaters for Safe Shutdown Cooling from any power level. The Basis for LC0 4.3.1 will be revised to state that the reheater sections are capable of providing cooling for other abnormal events, but are not relied upon to provide Safe Shutdown Cooling.

A second proposed LC0 change is that the EES sections shall be capable of receiving water from both the Emergency Condensate Header and the Emergency Feedwater Header during power operation, instead of the former minimum allowable of only one of these emergency headers.

Although the EES sections can be supplied water from both the Emergency Condensate Header and the Emergency Feedwater Header, only one of the two headers fs needed to supply the required cooling water for Safe Shutdown Cooling. The reheaters can be supplied with water from the Emergency Condensate Header, but not from the Emergency Feedwater Header.

These LC0 changes are desirable due to the limitations of a reheater section to adequately support Safe Shutdown Cooling with firewater following a ninety-minute Interruption of Forced Circulation (10FC).

This condition is described in LER 86-020 which was submitted to the NRC in Reference 1. This letter contains as Attachment 4 a Safety Analysis which demonstrates that reliance on the EES sections for Safe Shutdown Cooling meets all of the regulatory requirements for emergency cooling, once planned modifications to add six-inch vent lines to both loop main steam headers have been completed.

LER 86-026, which was submitted in Reference 2, described concerns regarding the capability of an EES section to adequately support Safe Shutdown Cooling from 105 percent power. PSC has submitted detailed analyses to the NRC in Reference 3 to justify operation using an EES section for Safe Shutdown Cooling at power levels up to 87.5% reactor power. These analyses also confirm the adequacy of shutdown cooling using ' ""s limiting 10 CFR 50, Appendix R Fire Protection cooling water flow path from approximately 82% reactor power.

PSC has determined that a reheater section cannot support Safe Shutdown Cooling from power levels above approximately 39% (see Reference 4). Since the proposed changes to LC0 4.3.1 only eliminate reliance on the reheaters for Safe Shutdowc Cooling, these changes do not affect the consequences of other accidents. By requiring both reheaters and both EES sections to be operable, the proposed changes increase the likelihood that the necessary heat exchangers would be available when called upon to provide cooling for other accidents and abnonnal events.

PSC is completing confirmatory analyses of these other accidents and abnormal events previously evaluated in the FSAR which do not involve Safe Shutdown Cooling. Preliminary results of these analyses

P-87002 Pag 3 January 15, 1987

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r indicate that the steam generator heat transfer sect 4 ns are capable of. supporting -decay heat removal and will not require power _ level limitations more restrictive than those analyzed in Reference 3. PSC will inform -the NRC of the final results of these confirmatory '

analyses in a future submittal.

4 Attachment .1 is a Summary of -Proposed Changes to the existing

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Technical Specifications. Attachment 2 contains the actual Proposed

. Changes-~to the Technical Specifications. Attachment-3 contains the

_Significant Hazards' Consideration. for the proposed changes. The i conclusion of Attachment 3 is that the proposed deletion _ of reliance on a' reheater section for Safe Shutdown Cooling does not constitute a.

significant safety hazard since, after installation of the above noted planned modification, the EES section will provide adequate

cooling for a safe shutdown following_ any event in which Safe Shutdown' Cooling using firewater is required. Attachment.4- contains I

the Safety Analysis Report' upon _which -the Significant Hazards Consideration is based.

In accordance with the provisions of 10 CFR 170, an application fee of $150 is enclosed..

If.. you have any questions or comments 'concerning the enclosed information, please call Mr. M.H. Holmes at '(303) 480-6960.

Very truly yours, f A R.O. Williams, Jr.

Vice President 4

4 Nuclear Operations R0W/JRJ:jmt Attachments cc: Albert J. Hazle .

Colorado Department of Health i

J. E. Gagliardo Region IV, NRC R. E. Farrell NRC Senior Resident Inspector, FSV

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter )

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Public Service Company of Colorado ) Docket No. 50-267 Fort St. Vrain Unit No. 1 )

AFFIDAVIT R. O. Williams, Jr., being first duly sworn, deposes and says:

That he is Vice President, Nuclear Operations, of Public Service Company of Colorado, the Licensee herein, that he has read the foregoing Application of Amendment to Appendix A of Facility Operating License and knows the contents thereof, and that the statements and matters set forth therein are true and correct to the best of his knowledge, information and belief.

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/Who R. O. Williams, Jr.

Vice President Nuclear Operations STATE OF /7N'fru?I/e > )

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COUNTY OF 81nfav )

Subscripve and sworn to before me, a Notary Public on this

/f- day of bum ///-  !

, 1987.

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My commission expires Nuduff31) ,198f J

FORM (B) 372-20-4033 ,

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23-1/1020 DATE danU8r_v13.1985 Pusuc SERVICE COMPANY OF COLORADO FORT SAINT VRAIN THE FIRSTINTERSTATE BANK OF DENVIIt, N.A.

PAYABLE AT t7 M

nooeo U Q Q g L, DENvE=. CotonAoO PAY "" One Hundred Fiftv Dollars and no/100 -------------------DOLLARS $ - 150_00--

VOID AFTER 90 DAYS PUBUC SERVICE COMPANY OF COLORADO DIVISION ACCOUW VO #

THE U. S. Nuclear Regulatory Comission ioutv one sioniwas uscissany i, uoO on tissi "o/* Washington, D. C. 20555 L _.]

n'ODBB S 2a' 8: 1020000181: S 4 3 9 5 7 ana REMITTANCE ADVICE. PLEASE DETACH FOR YOUR RECORDS. g7 nggg THE ABOVE CHECK IS IN PAYMENT FOR THE FOLLOWING ITEMS. M UQQU YOUR ACCOUNT TO BE CHARGED INVOICE Perform Control Res Cho Order / Code m Spaces 0 rey, DESCRIPTION AMOUNT 4R12 67 R4 Technical Rnoeificatinn Fooe 1Rn nn

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