ML20128D897
| ML20128D897 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 02/26/1974 |
| From: | Basdekas D US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Ippolito T US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 9212070417 | |
| Download: ML20128D897 (2) | |
Text
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FEB 2 61974 I
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f-Docket No. 50-263
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i-j Thomas A. Ippolito, Chief, Electrical, instrumentation & Control 4
l Systems Branch, L i
1' GENERAL ELECTRIC PROPOSED PROMPT RELIEF TRIP (PRT)- STETEM'FOR j
!!ONTICELLO 1
j On February 20 and 21, 1974,- a meeting chaired by J. J. Shea,
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ORB-2, eas held'with General Electric and Northern States Power Company to discuss the proposed Prompt Relief Trip System I
i intended to enhance the scram reactivity insertion rate which 1
i was found by G.E. to be deficient toward the end of the fuel
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cycle for BWRs in general'.
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A brief sunanary of an earlier G.E. presentation on the ' subject j
was given as reported =in my memo to you of' october 18, 1973.
i Additional information was presented on'the details of the PRT 1mplementation in Monticello largely contained in the applicant's submission of January 23, 1974.
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i The PRT, as proposed during this meeting, is intended to satisfy j
the requirements of IEEE 279.
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Our review of the electrical and instrumentation aspects of the-proposed PPT has not been performed, and questions such as single failure proofness, interaction with the ADS, reliability with regard to function performance on demand. testability and inadvertent j-actuation cranot be answered at this time.
The applicant is aining at getting our approval for installing a PRT but not "outrating" it until our: review is-couplete.and our approval final.
r Technical aspects of keeping the PRT de-activated after installation-j are not unworkable.
i During the discussion with the applicant and G.E. the following items came up that are of interest in making a determination of the-I safety metits 'of the PRT as proposed'in the Monticello caset
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j T. A. Ippolito
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The PRT function, without any other desi8u changes considered._
i will be required only for something like 20% of the operating 4
life of the plant, toward the and of the fuel cycle, yet it 3
will be challenged throughout the finel cycle.
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2.
Not all viable alternatives and combinations thereof have s
1 been considered and/or analyzed with specific reference to i
i the present Monticello design. A notable case in point is 1
j that it has not been analyzed with reference to the recirculation i
ptasp trip as implemented for the ATWS fix.
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3.
The present Monticello design has a reactor scram initiated j
by low condonser vacuum before a turbine trip setpoint is reached. The presently available and/o1 enhanced. turbine bypass capability with possibic changes in the bypass system-4 have not been analyzed.
4.
The question of inadvertent and/or unnecessary actuations in conjunction with the bad history of the relief valvos sticking open remains at best, a cute one.
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Demetrios L. Basdekas t
Electrical, Instrumentation &
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-Control Systems Branch Directorate of Licensing 3,
y, cci V. Stello i
D. Ross-T. Novak
,r C. Bailey W. Minners p
EI&CSB Hembers 4
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