ML20151X241

Forwards Discussion of & Proposed Revs to Tech Specs for Resolution of NRC Comments Concerning Deletion of Auxiliary Feedwater Pump Turbine Inlet Steam Pressure Interlock Operability Requirements,Per 880406 Telcon

ML20151X241
Person / Time
Site:	Davis Besse
Issue date:	04/29/1988
From:	Shelton D TOLEDO EDISON CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML20151X244	List: ML20151X241 ML20151X266
References
1508, TAC-65374, NUDOCS 8805040093
Download: ML20151X241 (4)

Text

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A Cueru Derp Cmw i DONALD C, SHELTON

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Docket No. 50-346 License No. NPF-3 Serial No. 1508 April 29, 1988 United States Nuclear Regulatory Commission 4 Document Control Desk Vashington, D. C. 20555

Subject:

Resolution of NRC Comments Related to License Amendment Request Regarding Deletion of Auxiliary Feedvater Pump Turbine Inlet Steam Pressure Interlock Operability Requirements (TAC No. 65374)

Gentlemen In a telephone conversation between NRC (A. V. DeAgazio, tmC/NRR Davis-Besse Nuclear Power Station Unit No. 1 Project Manager, and N. Vagner, NRC Staff) and Toledo Edison (TED) representatives on April 6, 1988, TED proposed resolution to NRC comments previously received concerning the subject I.icense Amendment Request. These comments involved reservations the staff had regarding the deletion of the Auxiliary Feedvater Pump Turbine (AFPT) Inlet Steam Pressure Interlocks from the Technical Specifications, as proposed by Serial No. 1377 dated May 4, 1987, based on the credit taken for the '

interlocks as part of the Environmental Qualification Program. .

Enclosure 2 to this letter provides TED's discussion of and proposed revisions to the Technical Specification pages for the resolution discussed in the above referenced conversation. This resolution is considered additional information '

vithin the scope of the original application as submitted by Serial No. 1377 and requires no license fee per 10CFR170.12.

Very tru ours,

, ML RHC:tlt ao 69 Enclosures Be050gggy $$o PDR p

cc A. B. Davis, Regional Administrator p0 DB-1 Resident Inspector j k A. V. DeAgazio, DB-1 Project Manager \

State of Ohio THE TOLEDO EDISON COVPANY ED SON PLAZA 300 MAD! SON AVENUE TOLEDO. OWO 43652

j Dockat No. 50-346 '

'i Lic;nsa N3. NPF-3 .l Serial No. 1508  !

Enclosure 1 l Page 1 l l

ADDITIONAL INFORMATION TO I l

APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POVER STATION UNIT NO. 1 Attached is additional information related to the License Amendment Application regarding deletion of the Auxiliary Feed Pump Turbine Inlet Steam Pressure Interlocks, previously submitted on May 4, 1987 (Serial No. 1377).

The proposed Technical Specification changes affected by this additional information (submitted under cover letter Serial No. 1508) concern:

Technical Specification 3/4.7.1.2, Auxiliary Feedvater System Technical Specification Bases Section 3/4.7.1.2, Auxiliary Feedvater Systems s

By: [ AA D. C. Shelton, Vice President, Nuclear Svorn and subscribed before me this 29th day of April,1988.

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NFtarf Public, State of Ohio My Commission expires b /

p Docket'No. 50-346 Licenza No. NPF-3 Serial No. 1508 Enclosure 2 Page 1 Discussion of Resolution to NRC Comments Related to -Toledo Edison's Prcposed License Amendment Request Regarding Deletion of Auxiliary Feedvater Pump Turbine Inlet Steam Pressure Interlock Operability Requirements.

In a telephone conversation on March 24, 1988 between the NRC (A. V. DeAgazio, NRC/NRR Davis-Besse Nuclear Power Station (DBNPS) Unit No. 1 Project Manager) and TED, comments were provided regarding the License Amendment Request (LAR) concerning deletion of the Auxiliary Feedvater Pump Turbine (AFPT) Inlet Steam Pressure In+.ctlock operability requirements from Technical Specification 4.7.1.2d (Serial No. 1377, dated May 4, 1987). These comments pertained to the NRC Staff's review of the Impell Report No. 02-1040-1334, Revision 0, "Evaluation of Environmental Conditions from Auxiliary Feedvater Pump Turbine Steam Supply Line Ruptures", November 1985, as was referenced in the LAR.

Subsequent discussion on March 30, 1988, revealed the concerns could be alleviated if the interlocks were to remain in the Technical Specifications.

TED re-emphasized that the interlocks were only required for environmental qualification concerns and, therefore, Auxiliary Feedvater System (AFVS) operability should not be related to the interlock operability. It was noted by TED that the operability of this interlock vas required only when the lines were pressurized above 275 psig, based on the criteria for high energy lines provided in the Updated Safety Analysis Report, Section 3.6. Further, since the interlock is only required for mitigation of high energy line break consequences, a greater action time should be allowed in the event of i inoperability of the interlock.

In a telephone conversation on April 6, 1988, TED proposed the following specific items to resolve the NRC concerns:

, 1) The existing Surveillance Requirement nun'bor 4.7.1.2 vould be revised to

! 4.7.1.2.1, and, based on the new numbering, surveillance Requirement 4.7.1.2.1d would be revised to delete the AFPT Inlet Steam Pressure Interlocks surveillances and to remove these interlocks from AFVS l operability considerations. However, the AFPT Inlet Steam Pressure Ir.terlocks vould be included in a separate Surveillance Requirement

, numbered 4.7.1.2.2 that would require nperability of the interlocks when i the steam line pressure is greater than 275 psig. This vould allow the 4

! interlock pressure switches to be set at a higher setpoint to accommodate j the high energy line break (HELB) concerns, and not be required to be operable for all conditions for which the AFVS is required to be operable-

The higher trip setpoint is also expected to alleviate the interlock

pressure switch (manufactured by Static-0-Ring) setpoint drift which

occurs when the svitch is calibrated at the lover end of its range. Also

! included in this separate Surveillance Requirement is a delineation of the l maximum allovable time following exceedance of 275 psig that vill be permitted to perform the interlocks'surveillances.

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Dockat N]. 50-346 Lic:nsa N3. NPF-3 Serial No. 1508 Enclosure 2 Page 2

2) A new Action Statement b. vould be added to Specification 3.7.1.2 for the AFPT Inlet Steam Pressure Interlocks as follovst

b. Vith any Auxiliary Feed Pump Turbine Inlet Steam Pressure Interlocks inoperable, restore the inoperable interlocks to OPERABLE status within 7 days or be in HOT SHUTDOVN vithin the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

The new Action Statement voJ1d allow a longer action time to remedy the condition where any AFPT Inlet Steam Pressure Interlocks are inoperable, and is justified by the probability of a HELB being lover than the probability of an event which would require AFVS actuation. This is consistent with the classification of events presented in the Updated Safety Analysis Report (USAR), Chapter 15. This chapter of the USAR defines a Loss of Normal Feedvater event (which would result in AFVS actuation) as a Class I event, or an abnormal operational transient, and defines a Steam Line Break event (which includes the AFPT steam supply line) as a Class III event, or an accident which has very lov probability.

Therefore, the increased action time for restoring any inoperable AFPT Inlet Steam Pressure Interlock to operable status is justified.

3) The Bases for Section 3/4.7.1.2 vould be revised to include a statement as follovst The OPERABILITY of the Auxiliary Feed Pump Turbine Inlet Steam Pressure Interlocks is required only for high energy line break concerns and does not affect Auxiliary Feedvater System OPERABILITY.

This statement in the Bases vould clearly indicate the interlocks are not associated with AFVS operability.

The marked up Technical Specification pages are included as part of this enclosure and reflect the above cited discussion.

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