ML18082A988
| ML18082A988 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 08/19/1980 |
| From: | Librizzi F Public Service Enterprise Group |
| To: | Eisenhut D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8008270381 | |
| Download: ML18082A988 (3) | |
Text
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PS~G e Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 Phone 201 /430-7000 Mr. Darrell G. Eisenhut, Director Division of Licensing U.S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Sir:
August 19, 1980
SUMMARY
OF MITIGATING CORE DAMAGE TRAINING The attached is a summary of the training material for Mitigating Core Damage Training.
This training is presently being given to Salem licensed operating personnel and the support staff.
Attachment 1879 1979 8008276 ~'61 Sincerely yours, Frank P. Librizzi General Manager -
Electric Production 95-2001 (300M) 1-79
Mitigating Core Damage Training: A Summary DAY ONE: Natural Circulation Following a Small-Break LOCA:
This segment of the course addresses natural circulation (by definition),
the steady-state flow equation, and factors which affect natural circu-lation. A graphic description of the various modes of natural circulation and decay heat removal (from WCAP 9600), including progression from one mode to another, is developed. Sources of non-condensable gas production, and their effects on steam generator performance, are discussed.
. Excore Source Range Instrument Response:
This segment of the course addresses the normal operation of a BF3 proportional counter, physical location, and normal shutdown behavior of this instrument. Reasons for selection of the Source Range as a means of predicting core conditions are discussed. Accident response with respect to the following areas are covered in this area: (1) source neutrons, (2) voiding effects on reactor kinetics, (3) void location effects on detector response, (4) location of the detector on detector response, and (5) homogeneous vs. void-separation. The previous dis-cussions are then applied to the TMI-2 source range strip chart recording.
Incore Thermocouples:
This segment of the course addresses the theory of operation of a thermo-couple (including production and measurement of an EMF), basic construct-ion (to develop the difference between "Measurement" and "Reference" junction temperatures), and the effects of varying reference junction temperature. Salem's thermocouple system is reviewed, with special em-phasis on the computer program for developing the subcooled margin (temperature and pressure) calculations. Thermocouple use during accident conditions is discussed, including methods of obtaining direct readout at the instrument panel.
DAY TWO: Incore Movable Detector Response:
This segment of the course addresses the theory of operation of the fission chamber, development of the low-current gamma response (shut-down), and hypothesizes the output trace response for: (1) a partially voided core, (2) total voiding in the core, and (3) severe core damage (with full detector travel possible). Additionally, a method for assessing the approximate magnitude of radial damage when detector travel is re-stricted is also proposed.
Post-Accident Primary Chemistry:
This segment of the course addresses the effects on radiochemistry for varying degrees of core damage. Development of the basic gross S-y act-ivity calculation is performed, for the purpose of illustrating the "normal" baseline data. Calculations are then performed which consider (1) release and escape mechanisms, (2) type of core damage (rod burst or melt, and (3) the degree of core damage; these calculated values are then compared to the normal values to illustrate the potential post-accident value of these analyses.
DAY TWO: Radiological Hazards of Sampling:
(Cont'd)
This segment of the course addresses the radiological hazards of drawing a theoretical primary sample, following an accident which involves core damage. Potential doserates from (1) the Xe "cloud", (2) the sample bottle itself, and (3) a spilled sample bottle are calculated with the student. Sampling precautions and upcoming design changes to allow safe post-accident sampling are discussed.
DAY THREE: Determining Doserate Inside Containment from Exterior Measurements:
This segment of the course addresses the ability to determine approx-imate doserates inside containment, based on external readings. Included is a problem in determining the shielding effectiveness of the as-built containment shell and, utilizing this calculation, the development of a thumbrule for determining the approximate internal dose from an external measurement.
Hydrogen Hazards During Severe Accidents:
This segment of the course addresses sources of H2 and o2 production during normal and post-accident conditions. Also discussed are :
(1) hazardous concentrations and limits for H2, (2) characteristics of H2 "burns", (3) principles of operation of the installed H2 detectors, (4) the effect of containment isolation on H2 measurement, and (5) methods of controlling the H2 concentration. The Zirconium-water reaction, and its mechanics, are discussed in detail.
Post-Accident Containment Environmental Effects:
This final segment of the course addresses two major topic areas:
(1) potential ef.fects o.f the post-LOCA environment on containment piping systems and (2) instrumentation response. Included is a summary of the results of Westinghouse environmental testing programs on pip-ing and instrumentation and discussion as to how the post-LOCA envir-onment will affect the incore thermocouples, RTD's, Barton ITT trans-mitters, and source range instrument response.
The course itself requires approximately 2~ full days to teach:
the afternoon of the third day is spent in study and review. A short exam covering the material is administered on the morning of the fourth day (the exam consists of 12 essay questions); the exam questions, and correct answers, are reviewed in the afternoon of the fourth day.