ML25195A194
| ML25195A194 | |
| Person / Time | |
|---|---|
| Issue date: | 10/09/1979 |
| From: | Carbon M Advisory Committee on Reactor Safeguards |
| To: | Gilinsky V NRC/OCM |
| References | |
| Download: ML25195A194 (1) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, D. C. 20555 October 9, 1979 The Honorable Victor Gilinsky Commissioner U. s. Nuclear Regulatory Commission Washington, D. c. 20555
Dear Dr. Gilinsky:
In response to your letter of September 12, 1979, we offer the following comments relative to the emission of xenon fran the 'lMI-2 nuclear plant and the possibility of reducing such releases in similar accidents which may occur in the future.
So far
- as we know, the comments on the various approaches for estimating the total quantity of xenon released following the accident appear reason-able.
In terms of controlling xenon releases in accidents which may occur in the future, we believe that chilled or cryogenic charcoal adsorption beds of adequate capacity would be helpful.
Adsorption systems using this principle are commercially available and are in successful operation for handling routine releases at several nuclear power plants. The major problems would be possible decreases in the effectiveness of such beds under conditions which involve the larger volume and moisture content of releases accompanying an accident, and the difficulties in assuring that all the xenon emissions are collected so they can be effectively directed to and treated by the adsorption system.
Other methods, such as low temperature liquefication and fractional distillation may also be usable for removal of radioactive noble gases.
As noted above, the technology exists and has been applied in BWRs and PwRs to remove and retain for decay purposes certain radioactive noble gases before discharge as gaseous effluent.
The systems have not, however, been applied under accident conditions where multimegacurie releases may occur essentially in bursts or over relatively short time intervals, such as was experienced during the 'lMI-2 accident.
The Committee believes that a study should be undertaken to determine the applicability and desirability of available technology to minimize the release of radioactive noble gases during various postulated accident scenarios.
The study should include assessment of the various potential pathways for radioactive gaseous re-leases as well as considerations of accelerated rates of treatment of large gas volwnes such as those existing in large containments.
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The Honorable Victor Gilinsky October 9, 1979 Anticipating the need for answers to the types of questions raised in your letter, the Committee requested about a year ago that an ACRS Fellow develop a report sunrnarizing experimental data on the performance of charcoal beds under a variety of parameters. It is anticipated that this report will be completed within the next two to three months, and we will plan to provide a copy to you at that time.
cc: Joseph M. Hendrie, OCM Richard T. Kennedy, OCM Peter A. Bradford, OCM John F. Ahea me, OCM samuel Chilk, SECY Lee V. Goss ick, EOO Sincerely, 2142