GO2-83-985, Final Deficiency Rept,Condition 287 Re Mod to Maintain Equipment Qualification.Initially Reported on 830920.Valve RCIC-V-8 Will Be Modified to Close in 12.1 & Reactor Bldg Northwest Stairway Opening Will Be Modified

Final Deficiency Rept,Condition 287 Re Mod to Maintain Equipment Qualification.Initially Reported on 830920.Valve RCIC-V-8 Will Be Modified to Close in 12.1 & Reactor Bldg Northwest Stairway Opening Will Be Modified

ML20081H778
Person / Time
Site:	Columbia
Issue date:	10/28/1983
From:	Carlisle C WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
10CFR-050.55E, 10CFR-50.55E, 287, GO2-83-985, NUDOCS 8311070579
Download: ML20081H778 (3)

Text

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Washington Public Power Supply System P.O. Box 968 3000 GeorgeWashington Way Richland Washington 99352 (509)372-5000 October 28, 1983 G02-83-985 e

AMr.J.B. Martin

- Regional Administrator

$ EU.S. (uclear Regulatory Commission

$hl .__ Region V y; = i1450M 4 gWalnu)ariaLane, Creek, California Suite 94596210

Subject:

NUCLEAR PROJECT NO. 2 10CFR50.55(e) REPORTABLE CONDITION #287 MODIFICATION TO MAINTAIN EQUIPMENT QUALIFICATION

References:

a. Telecon dated September 20, 1983, R.T. Johnson to D. Haist, same subject.

b. Letter BRGO-R0-83-013, dated September 29, 1983, W.G.

Conn to Office of Inspection and Enforcement, same subject.

In accordance with the provisions of 10CFR50.55(e), your office was informed by the references above, of the subject condition. The attachment provides the Project's final report on Condition #287.

If there are any questions concerning this matter, please contact Roger Johnson, WNP-2 Project QA Manager, (509) 377-2501, extension 2712.

C S Program Director, WNP-2 RTJ/kd

Attachment:

As stated cc: W.S. Chin, BPA N.D. Lewis, EFSEC A. Toth, Resident Inspector Document Control Desk, NRC 8311070579 831028 PDR ADOCK 05000397 S PDR j6 .0

4 .

e WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PROJECT NO. 2 DOCKET NO. 50-397 LICENSE NO. CPPR-93 10CFR50.55(e) CONDITION #287 MODIFICATION TO MAINTAIN EQUIPMENT QUALIFICATION FINAL REPORT Description of Deficiency General Design Criteria 4 states "... structures, systems and components impor-tant to safety shall be designed to accommodate the effects of, and to be compatible with the environmental conditions associated with... postulated accidents. These structures, systems and components shall be appropriately protected against dynamic effects...that may result from equipment failures...

events and conditions outside the nucleai power unit."

In the consideration of this criterion on Supply System Nuclear Project No.

2, pipe breaks were postulated for each high energy line in the Reactor Build-ing for determining adverse impacts on safety related equipment. For selected zones adjacent to these postulated pipe breaks, the environmental conditions are controlled by these events.

During Design Verification deficiencies were discovered in the environmental calculations used as the basis for equipment qualification.

Revision to the analysis, using corrected assumptions, resulted in temperature and humidity profiles which exceeded the condition for which the safety re-lated equipment had been qualified.

Safety Significance The safety related equipment in the Reactor Building necessary for achieving and maintaining safe shutdown, was being qualified to the environmental condi-tions determined in the original analyses. The results of the revised analy-ses exceeded the original environmental conditions and, consequently, the equipment (which had been previously considered qualified to function) could no longer be proven to remain functioning during a postulated high energy line break event and maintain safe shutdown.

Cause for the Deficiency The original high energy line break analyses for pipe breaks outside contain-ment, incorrectly assumed the normal Reactor Building ventilation system would remain functioning to mitigate the consequences of the worst case event com-binations. This system is neither seismically designed to function or environ-mentally qualified to function under the worst case condition.

For the worst case event combinations (seismic event, loss of offsite power, high energy break plus single active failure), the environmental qualification temperature and relative humidity profiles should have been based on calcula-tions assuming the Reactor Building ventilation system was not functioning for long-term heat removal.

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Final Report #287 Page 2 The calculations also assumed certain vent paths were available to relieve steam and provide cooling within the Reactor Building. However, many of these vent paths are now plugged for fire protection purposes and no longer avail-able to mitigate the effects of postulated pipe break events. This condition was reported to the Commission as a 10CFR Part 21 by Burns and Roe, Inc.

The circumstances in combination resulted in the cause for the deficiency.

Corrective Action Impell Corporation was contracted to independently review and revise the orig-inal high energy line break analyses used to determine the environmental condi-tions for equipment qualification. The Impell calculation review was directed '

toward the RWCU and RCIC high energy lines outside containment. The results of Impell's revised analyses indicated certain specific design changes were required to assure safety related equipment, as installed, remained qualified to withstand the temperatures and relative humidity. These design changes are:

1. Valve RCIC-V-8 will be modified to close in 12.1 seconds.

2. The Reactor Building Northwest stairway opening to the 572' elevation will be modified to leave a maximum opening of 15 square feet.

In addition, all other high energy line break analyses for the Reactor Build-ing were reviewed by the Supply System to determine whether similar incorrect assumptions were used. It was discovered the analyses of the environmental effects from a break in the Auxiliary Steam System (a non-safety system used primarily for space heating during the colder weather) also was based on incor-rect assumptions. These analyses were revised by the Supply System and an additional required design change identified in order to assure the environmen-tal conditions resulting from a postulated pipe break in this system would not result in conditions exceeding the qualification of safety-related equip-ment. This design change involves installation of isolation valves and instru-mentation to assure quick isolation of Auxiliary Steamline breaks in the Reac-tor Building.

Project Engineering Directives (PED's) are being issued to make the plant modifications via PED's 215-!i-X967 and 215-CS-X949 with the work scheduled to be completed prior to fuel load. The modification of the Auxiliary Steam System is scheduled to be completed before Commercial Operation, because of the long lead time required to purchase the necessary isolation valves.

(Reference G02-83-844, dated September 19,1983.)

Action to Prevent Recurrence The worksheets associated with the Burns and Roe Project Instruction (WNP 017) for preparing PED's and the procedure for preparing Supply System PED's (CS-WNP-2-017) has been modified to assure the design interfaces between fire protection features, pipe break requirements and other design changes are maintained.

All high energy line break analyses outside of containment have been reviewed to assure the error has not recurred.