ML20210B743
| ML20210B743 | |
| Person / Time | |
|---|---|
| Issue date: | 05/20/1965 |
| From: | Manly W Advisory Committee on Reactor Safeguards |
| To: | Seaborg G US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20210B278 | List: |
| References | |
| FOIA-86-346 ACRS-GENERAL, NUDOCS 8609180158 | |
| Download: ML20210B743 (3) | |
Text
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ADVISORY COMMITTEE ON REACTOR SAFEGUARDS
' UNITED STATES ATOMIC ENERGY COMMISs!ON
, WAsHINGTot125. D. C. .
M AY 2 01965 CLASSIFICATION CANCMPD o OR CHANGED TO M BY AUI RITY'OF O G_d.~- . ,b, ,
Honorable Glenn T. Seaborg Chairman BY . _M... DATS 8.-NIY U. S. Atomic Energy Commission Washington, D. C.
Sab)cct: REPORT ON NEW PRODUCTION REACTOR - OPERATION IN PHAS
Dear Dr. Seaborg:
At its sixty-third meeting on May 13-15, 1965, the Advisory Comittee on Reactor Safeguards reviewed the status of the Hanford N-Reactor in regard to the proposed Phase II Operation (production and the export o f steam) . Since it is planned to operate this reactor with steam ex- l ported to the dual turbine plant (800 MW(e)) later this year, an evalu-ation of the proposed operation at this time was desirable.
l l
I An ACRS Subcommittee met at the site on May 7-8, 1965, with representa-l tives of the General Electric Company (GE), the Washington Public Power Supply System (WPPSS) and its engineering consultants Burns & Roe, rep-resentatives of the Bonneville Power Administration (BPA), and the AEC scaff. At the sixty-third meeting, the Committee had the benefit ofThe discussions with representatives of GE, ,WP_PSS, and the AEC staff.
Committee also had the benefit of the documents referenced.
the Committee discussed the proposed In its letter of October 15, 1964, full power and also commented on the field operation of the N-Reactor at An extended pipe header, construction under way for Phase II Operation.
additional surge tank capacity, and a sixth cell were nearing completion '
The sixth cell contains two at the time of the Subcommittee site visit.
additional steam generators and one additional primary system coolant Two additional steam vents .
pump comparable to those already installed. These l for the sequential release venting system are also being added. The vents will be of the same design as the other 13 aircady in place.
secondary system is being modified by extendingEach the present export header line is pro- and connecting the eight steam export lines to it.
vided with two valves in series, one for isolation and the other for con-trol.
Steam can thus be routed to the dump condensers or exported to the new dual turbine plant.
8609180150 860915 PDR FOIA TAYLORR6-946 PDR s
Fo t A 34 p- 3 /11
( Honorable Glenn T. Seaborg MAY 2 01965 .
The surge capacity of the secondary system is also being increased for Phase II Operation by the addition of two tanks similar to the one now installed. During Phase II Operation, the secondary system will be operated at 150 psi although designed for eventual operation at much higher pressure.
The N-Rdactor haa been operated at design power since December 1964.
It has performed well, although some early difficulties were experienc-ed uith materials failures in the dump con,densers, steam generators, pressure reducing valves, and valve stems. Consistently good perform-ance has been obtained with the reactor instrumentation and safety sys- -
tems. Continued operation of the N-Reactor on a Phase I basis at full power is thus expected to be favorable.
The General Electric Company has examined possible sources of interac-tion of the turbine plant with the N-Reactor. By its contractual agree-ment with WPPSS and BPA, the General Electric Company will furnish steam only when safe to do so; hence, the N-Reactor export load requirements are independent of the turbine plant steam utilization. Approximately 14,000,000 pounds of steam per hour can be produced at the N-Reactor,
( while the maximum demand of the turbine plant is expected to be approxi-mately 12,000,000 pounds per hour. Because of this difference, steam will be continuously dumped to the dump condensers. These condensers are, therefore, always hot and ready for full load. Enough valving is provided so that limited valve malfunctions in the dump system should not create significant transients in the reactor. ,,
The General Electric Company has carried out extensive evaluation of transients which might be caused by single and double turbine trip-out, rapid shutdowns, reactor cooling system transients, and loss of elecyi-cal continuity. Tests of the turbine plant are planned to check the evaluations. These tests will determine if turbine malfunctions will create undesirable transients that require scram of the reactor. All
( other t:ansients appear to be protected against by the available safe-l guards. -
Electrical system faults have been analyzed with the asoistance of the BPA. N-Reactor power production is less than 5*/. of the BPA system capa-city. Ic appears that loss of power from the N-Reactor to the BPA sys-tem will not produce unacceptable feedback effects on the N-Reactor or other Hanford reactors. It was also ascertained that changes in the N-Reactor load will not adversely influence safeguards provided for the l other Hanford reactors.
f . AY 2 01965 Honorable Glenn T. Seaborg .
The response of the confinement system during Phase II Operation has also been analyzed to ascertain the effect of the change in the system parameters, brought about by the addition of the new sixth cell and its contents.
The maximum calculated pressure from a rupture producing the largest steam release is well below the building capability.
1 l
l The Committee also reviewed the qualifications of the WPPSS organization and staff for this plant.
The control r8cm at the turbine plant will be as well as provided with basic instrumentation on reactor plant output, The telephone, annunciator, and alarm signals 'for emergency evacuation.
communf. cation capabilities, as well as the protection and evacuation pro-cedures to be used by WFPSS personnel in the 'unlikely event of a serious incident, appear to be satisfactory.
The radiological consequences in the unlikely event of a severe reactor accident at the N-Reactor during Phase II Operation have been calculated and would exceed the dose criteria now used for licensed power reactors. and may She Gcneral Electric Company is continuing to. study this problem, be able to develop adequate control methods for Phase III Opera, tion to conform to the guideline dose values.
j The Committee believes that operation of the N-Reactor during Phase II for production and power purposes will not increase the existing hazard to the health and safety of the public. In the light of presently exist-ing information, the Committee believes that operation of the N-Reactor without further safeguards can only be justified by production requirements.
Sincerely yours, W. D. Manly Chairman Re ferenc es :
- 1. N-Reactor Phase II Operation Preliminary Hazards Summary Report, dated January 15, 1964 (C/RD) .
- 2. N-Reactor Phase II Operation Hazards Summary Report, dated January 15, 1965 (C/RD).
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