ML20210T194

Informs of Review of Rev 1 to SER Re PSAR Through Amend 23. CESSAR Outstanding Items,Including Atws,Design Changes to Shutdown Cooling Sys & Boron Dilution Analysis,Remain.Upon Resolution of Items,Psar Will Be Acceptable for CPs

ML20210T194
Person / Time
Site:	Satsop
Issue date:	10/01/1975
From:	Stello V Office of Nuclear Reactor Regulation
To:	Deyoung R Office of Nuclear Reactor Regulation
References
CON-WNP-1674 NUDOCS 8605290794
Download: ML20210T194 (6)

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UNITED STATES NUCLEAR REGULATORY COMMISSION W ASHINGTON. D. C. 20555 OCT 1IIIE  ;

1 Richard C. DeYoung, Jr., Assistant Director for LWR's, Group 1 RL f REVISION 1 TO SER - WASHINGTON PUBLIC POWER SUPPLY SYST 8 UNITS 3 & 5 Plant Name: WPPSS 3 & 5 l Licensing Stage: C Docket Nos.: S 50-508 509 Milestone No.: 21-Responsible Branc and Project Leader: LWR l-3, P. O'Reilly Requested Completion Date: August 29, 1975 (Reference, Ltr. to R. E. Heineman and D. Skovholt from R. C. DeYoung, Jr., ,

i Schedule for WPPSS 3 & 5 et.al., dated July 25, 1975)

Technical Review Branch Involved: Reactor Systems Description of Review: Revision to Update SER - Washington Public Power Supply System Units 3 & 5, letter to R. C. DeYoung, Jr.,

from Victor Stello, Jr., dated July 10, 1975.

Review Status: Complete thru WPPSS Amendment 23. .

The referenced letter SER from Reactor Systems Branch identified several

- unresolved items and problem areas with respect to the construci. ion appli-cation for WPPSS 3 & 5. The identified items represented the RSB evaluation of the project PSAR through Amendment 18, which incorporated CESSAR Amendments up to and including 21. On September 12, 1975, the applicant submitted Amendment 23, which included response to interface items in CESSAR Amendeents 36 and 37. Reactor Systems Branch has now reviewed the submittal through Amendment 23 and finds that the status of unresolved items has changed. A listing of unresolved CESSAR items identified in the referenced SER together with comments on the current status of these items follows:

CESSAR Outstanding Items (1) Anticipated Transients Without Scram must be reviewed and any required changes must be incorporated into the CESSAR design.

No change; the CE model is under review by the staff.

(2) Design changes to the shutdown cooling system to satisfy CDC 34 must be accomplished. Tliis item has been resolved pending documentation of design changes which have been agreed upon between EICSB and Combustion Engineering. However, WPPSS has taken exception to interface requirements which are necessary to the resolution of this problem, and it will become a WPPSS open item after resolution of CESSAR.

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OCT 11975 Richard C. DeYoung, Jr. (3) Pressurizer relief tank design - The CESSAR review of this item has been completed and we find the design acceptable; this item

. is resolved.

'(4) The ECCS performance evaluation must comply to the requirements of 10 CFR 50.46 and Appendix K (presently under review) - No change; additional information has been requested from Combustion Engineering.

(5) Flow restrictors are to be incorporated in the main steam lines -

CESSAR hss specified this as an interface item and the applicant has agreed to provide them unless Combustion Engineering can demonstrate that they are unaccessary for System 80. We find that the conuitment provided in Section 5.1.4 interface item I-2 of Amendment 23 of the applicant's PSAR is acceptable and consider this item to be reselved. Evaluation of the methods for the main steam line break analysis is scheduled for Beneric review. .

(6) Baron dilution analysis - Additional documentation is required from Combustion Engineering before the staff review of this item

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can be completed.

(7) Repressurization of Safety Injection Tanks - An additional unresolved item, repressurization of the safety injection tanks was identified as item 12(a) in Section 1.9 of the CESSAR SER. The design of the safety injection tanks provides for the manual depressurization of the tanks to 400 psig during plant cooldown and the manual pres-surization of the tanks to 600 psig during plant start-up. Additional e documentation is being' required to describe the proposed procedures, indications, and alarms to accomplish the repressurization function.

The outcome of the Reactor Systems Branch review of this item will I be applicable to WPPSS 3 & 5.

The status of WPPSS items addressed in the previous SER and new problem areas identified in subsequent WPPSS submittals follows:

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Richard C. DeYoung, Jr. .

WPPSS Outstanding Items (1) Overpressure Protection Design - In Amendment 23 to the WPPSS PSAR, the applicant 1ndicates that twelve safety valves are to be provided; four valves are to have set pressure equal to the main steam system design pressure (1255 psig) and the highest set pressure (four valves) will not exceed 1318 psig, with the middle set pressure at an intermediate value to be finalized during valve procurement. We have evaluated the design commitments with respect to the preliminary overpressure pro-tection analysis and assumptions used in the accident analyses and find the design acceptable for a construction permit. -

(2) NPSH Requirements for LPSI Pumps - Post-LOCA procedures described by the applicant include restart of the low pressure safety injection (LPSI) pumps during recirculation from the sump. The Amendment 22 response to our question 214.2 regarding monitoring and flow throttling control for this operation is acceptable.

However, a design evaluation of available NPSH for the LPSI pumps operating in the recirculation mode has not been provided. The applicant has provided such an evaluation for all other pumps taking suction from the sump in Section 6.3.2.14 of the PSAR. We will require this evaluation for the LPSI pumps before the design can be accepted for a construction permit.

(3) Conformance to Regulatory Guide 1.79 - The applicant indicates in j

Amendment 22 (Section 6.3.4) of the PSAR that the ECCS pre-operctional testing will conform to Regulatory Guide 1.79 with exception of j positions that require the pumps to take suction from the contain-i ment sump. We find this exception unacceptable and will require such tests.

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Richard C. DeYoung, Jr. OCT 1 575 (4) Steam Line Break Analysis - The applicant must identify any valves in the Main Steam and Feedwater Systems which will remain open to contribute to blowdown of the intact steam generator under assumed conditions of a steam line break coincident with a single failure (e.g., main steam isolation valve fails to close). The applicant must justify the existing steam line break analysis or provide a new analysis including maximum blowdown conditions.

(5) Compliance to CESSAR Interface Requirements - The documentation of CESSAR interface requirements and the intentions of the applicant with respect to these requirements is incomplete for

'this review. The applicant has indicated non-compliance with '

many safety-related interfaces in Amendment 23 and these items remain under review by the staff. However, several problem

, areas related to the non-compliance with interfaces have been identified in the plant review and are addressed in the items which follow.

(6) Shutdown Cooling Requirements - The CESSAR interface for cooling water supply to the Shutdown Cooling Heat Exchangers requires a flow of 5.46 x 106 WPPSS is providinglb/hrwithmaximumgnlettemperatureof105F.

a flow of 1.75 x 10 lb/hr at 95 0F. It is not apparent that the reduced flow rate proposed for the shut-down cooling heat exchangers vill provide the performance capability of the RHR system as presented in the CESSAR application.

A satisfactory resolution for this problem would be for the applicant to commit to the same design requirements set forth in the interface requirements in CESSAR. An equally acceptable alternative procedure would be for the applicant to demonstrate L that all of the performance requirements for the RHR system are satisfied with the reduced flow capability, i.e., that the RRR system would cool the primary system from an initial temperature of 350 F to 212 F in about 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> assuming a single failure in the RHR system.

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L OCT 1 IIN-Richard C. DeYoung, Jr. (7) Post-LOCA Cooling Requirements - CESSAR requires that 11,000 gpm of cooling water at 120'F be supplied to each shutdown

. cooling heat exchanger to' remove a heat load of 290 x 106 Btu /hr derint recirculation at 20 minutes after LOCA. The WPPSS PSAR (/.mendment 23) indicates that this interface is not applicatle; a component cooling water flow of 6000 gpm at 120'F will be provided as used in their containment transient analysis. The staff will require a breakdown of the duty requirements with comparisons to CESSAR in sufficient detail to explain and justify the reduced cooling water flow requirements, (8) Removal of Power from Atmospheric Dump Valves - The applicant has proposed that electric power be removed from the control circuit for atmospheric steam dump valves to preclude spurious opening during power operation. Power is to be restored to assist in removing decay heat after reactor shutdown. This propoBal is under review.

(9) Removal of Power from Main Steam Isolation Valve Bypass Valves -

The applicant has proposed to remove power.from control circuits

, for these valves instead of providing a single failure proof design. This proposal is under review.

(10) Protection of Safety Injection Tanks from Pipe Whip - The applicant has indicated, that safety injection tanks will not be protected from pipe ruptures that do not require operation of the safety injection system. The staff will require identification of those potential pipe ruptures for which safety injection tanks will be afforded no protection from consequential effects.

Reactor Systems Branch has reviewed the WPPSS 3 & 5 PSAR through Amendment 23 and concludes that upon satisfactory resolution of CESSAR items (1), (2). and g (4) from our original list plus CESSAR item (7) above and upon satisfactory

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Richard C. DeYoung, Jr. 1ON g7 resolution of the WPPSS problems identified above including all inter-face requirmeents, the plant design as described through Amendment 23 of the applicant's PSAR will be acceptable for a construction permit.

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/ll sistant Director for Reactor Safety Division of Technical Review Office of Nuclear Reactor Regulation cc: S. Hanauer -

-R. Heineman

'R. Boyd O. Parr P,- O'Reilly W. Mcdonald -

V. Stello T. Novak 2 Rosatocry L. Phillipa O

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