ML20003D413
| ML20003D413 | |
| Person / Time | |
|---|---|
| Issue date: | 02/11/1981 |
| From: | Felton J NRC OFFICE OF ADMINISTRATION (ADM) |
| To: | Hollar D DEBEVOISE & LIBERMAN |
| Shared Package | |
| ML20003D415 | List: |
| References | |
| FOIA-81-16 SECY-80-504, NUDOCS 8103270091 | |
| Download: ML20003D413 (2) | |
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February 11, 1981 Dale E. Hollar, Esquire Debevoise & Liberman 1200 Seventeenth Street, N.W.
IN RESPONSE REFER Washington, DC 20036 TO F01A-81-16
Dear Mr. Hollar:
This is in response to your letter dated January 14, 1981 in which you requested, pursuant to the Freedom of Information Act, copies of all documents relating to the possible formation of review panels, task forces, committees, etc. to study the issues raised by the Stratton et al. information.
The documents listed on the appendix are subject to your request.
Documents 1 through 5 are already available for inspection and copying at the NRC Public Document Room (PDR) located at 1717 H Street, N.W.,
Washington, DC. A copy of each of the remaining documents is enclosed.
Sincerely,
/fr
.;f/pm J. M. Felton, Director l
Division of Rules and Records m
Office of Administration
Enclosures:
As stated l
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F01A-81-16 APPENDIX
(
l.
Site Evaluation / Reactor Radiological Effects Joint Subcommittee Meeting held May 21-22, 1980 (ACRS-1751).
2.
Minutes of 242nd ACRS Meeting held June 5-7, 1980 (ACRS-1756).
3.
Report on Draf t Final Rule on Emergency Planning 10 CFR 50 and 70 (ACRS-885).
4.
Transcript of Site Evaluation / Reactor Radiological Effects Joint Subcommittee Meeting held May 21-22, 1980 (ACRST-754).
5.
Transcript of 242nd ACRS Meating held June 5-7, 1980 (ACRST-759).
6.
INFORMATION REPORT, SECY 80-504, to the Commission from H. R.
Denton November 13, 1980.
7.
Re-Assessment of Accident Source Terms, December 2,1980 (Personal Record by W. Pasedag prepared for DSI mgt, briefing) 8.
Planning Meeking on State of Technology Report on I, December 4, 1980, Summary of Key Points and Actions.
9.
Memorandum for William J. Dircks, from Guy Arlotto December 22, 1980.
- 10. Note to:
Denwood F. Ross, Jr., from William E. Kreger, January 1, 1980.
- 11. Memorandum for Denwood F. Ross from W. F. Pasedag January 9, 1981.
- 12. Letter to C. Kelber from S. Ebbin, NSOC January 2, 1981.
- 13. Letter to S. Ebbin from C. Kelber, January 7,1981, 14.
Letter to Levenson, EPRI, from R. Minogue, January 7,1981.
- 15. Memorandum to T. Rehm from R. Minogue, January 19, 1981.
- 16. Letter to Youngdahl, Consumer Power, from R. Minogue, January 26, 1981.
- 17. Memorandum for J. Carson Mark from John Ahearne, January 14, 1981.
18.
Memo to J. Ahearne from R. Minogue, State of Release of Fission Product Iodine, December 22, 1980.
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J. :. Folton, Director FREEDOM OF INFOrd.tATION Division of Rules and Records ACT REQUEST Office of Administration U.S. Nuclear Regulatory Commission
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20555 Re: Freedom of Information Act Request b~
Dear Mr. Felton:
The Nuclear Regulatory Commission Staff prepared a Staff Technical Analysis of Motion for Reconsideration which accompanied the NRC's Memorandum and Order, CLI-80-40 (December 5, 1980).
This Analysis states at 11:
"The staff believes that this [Stratton, et al.] infor-mation raises generic concerns that require general com-prehensive treatment and intends to treat it in that way".
Pursuant to the Freedom of Information Act, Debevoise & Liberman requests copies of all documents prepared by the NRC, its Staff and consultants since tne issuance of this Analysis relating to the Staff's plans to afford a " general comprehensive treatment" to the Stratton, et al._ information.
We specifically request copics o'f all documents relating to the possible forma-tion of review panels, task forces, committees or other entities to study the issues raised by the Stratton, et al. information. Such documents should include any drafts, supporting material, studies, reports, corres-pondence, minutes of meetings and transcripts regarding plans for such treatment.
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. We request that this information be provided with all possible dispatch and in no event later than the
- 10 vorking days provided by 10 C.F.R. 59.8.
Very truly yours, DEBEVOISE & LIBERMAN By Dale E. Hollar
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a UNITED sTATO flUCLEAR REGULATO.7Y COT.'t.t!C3 TON November 13, 1980 WAsNutGTo J, m. c. 2cs55 SECY-80-504 lii! FORMAT 101\\l REPORT For:
The Comissioners From:
H. R. Denton f
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W. J. Dircks, ED0 4
Subject:
IODINE RELEASE DURING REACTOR ACCIDENTS
Purpose:
To inform the Comission of the staff's discustions with Drs. W. R. Stratton, A. P. Malinauskas, and D. 3. Campbell; to sumarize the poteJ+ial impact of their hypotheses concern-ing lodine release durir.3 reactor accidents; and to propose an agenda for the Comission meeting on this topic. on November 18.
Background:
In a letter to Cnairman Ahearne dated August 14, i980 (enclosed as Attachment 1) three scientists from Los Alamos and Oak Ridge Natior.al Laboratories expressed their belief that cur' rent NRC models and Regulatory Guides do not correctly describe the release of iodine during nuclear reactor accidents. The staff invited the three scientists to ciscuss the technical bases of their letter.
On October 22, 1980 Drs. Stratton,' Malinauskas and Campbell met with about 40 memoers of the staff.
The minutes of this meeting and the attendees list are enclosed (Attachment 2).
As a result of a request 4' rom the three presenters at that meeting, the staff has suggeste.d
'.n agenda for the Comission's meeting on this topic, which is enclosed as Attachment 4 Discussion:
10 CFR 100 requires the postulation of a Design Basis Accident, "hypothes1:ed for the purpose of site analysis... that wou!d result in potential hazards not exceeded by those from any accident consid-ered creaible." Reg. Guides 1.3 and 1.4 define the assumptions to be made to meet this requirement, which include an assumed release from the fue1 into the containment of 1007, of the core inventory of noble gases and 257. of the iodine. Because of its relative abun-dance, its high radiotoxicity, and its assumed release and tr.ansport in vapor (elemental or organic compounds) form, radioiodine is.nearly always the most significant fission product, from a persor.nel hazara viewpoint, in design basis accident evaluations.
In their letter to Chairman Ahearne dated August 14, 1980, Drs. W. R.
Stratton, A. P. Malinauskas, and D. O. Campbell reported their opinion that current NRC models and Regulatory Guides are in error, and that tehavior projected from these models grossly ove. estimates the public risk resulting from reactor accidents due to the assumption that significant amounts of radiciodine can be released to the atmosphere Ccatact:
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Chairman John Ahearne U.S. Nuclear Regulatory Co= mission 1717 H Street Washington, D.C. 20535
Dear Chairman Ahearne:
We wish to bring to your attention a catter that.may be a very 'important devel-op=ent in reactor safety analysis. We believe that sufficient evidence has accumulated to show that the behavior of iodine during nuclear reactor accidents is not correctly described by existing NRC rodels and Regulatory Guides.
Ioding volatility is grossly overestimated by these models for accidents in which sub-stantial an.ounts of water are present, and escape of iodine to the environment will be extremely s=all (as it was at Three Mile Island) as long as reasonable contain=ent integrity is also maintained. As a consequence, the risk to the general public presented by iodine is lower than estimated, perhaps by orders of magnitude.
Our concern with this issue originated with our involvement in the several Technical Staff Analyses for the President's Commission on the Accident at Three Mile Island.
The ecchanism for the behavior of iodine that va propose here was derived from those analyses, from further examination of experimental and theoretical studies involving the chemistry of iodine and cesium fission pro-ducts in light water reactor fuel and systems, and from the observed behavior of iodine subsequent to fuel failures during accidents and incidents at other reac-tor sites.
We believe that the explanation presented here vill change the pre-sent concepts of the hazards involved during and subsequent to reactor accidents and, therefore, vill require a.ritical reexamination of how these hazards and risks are calculated, and the criteria to which engineered safeguards are designed and installed.
Although the Three Mile Island,(TMI) reactor core inventories of xenon-133 and iodine-131 vere comparable, between 2.4 and 13 million curies of xenon escaped to the environment during the accident, while only 13 to 18 curies of iodine similarly escaped!
This great disparity 'was identified as a matter of crucial inpe-
.e early in the invettigation by the President's Co= mission, and an effort was made to find the explanation.
It was clear that we could not claim 5
6 to understand the accident until this discrepancy (a factor of 10 to 10 ) was explained satisfactorily.
Further, it was recognized that the physical and chemical conditions during the accident at TMI mrt not have been tuique.
(We j
note that, generally, radioiodine is the~ controlling fission product species with respect to site safety analysis as well as the design and operation of certain engineered safegu.rds.)
Chair =an J. Ahearne August 14, 1980 The explanatior. for the very low escape of iodine that developed during the investigation by the President's Commission was that, as the temperature of the core increased, iodine diffused out of the fuel rods through the failed cladding and vaporized.
The iodine escaping, if not already in the iodide form, then encountered a chemically reducing environment which converted it to iodide.
The iodide subsequently went into solution as iodide ion w en it contacted water.
h It was recognized that additional experimental work was needed to provide a quantitative description of the iodine behavior.
N:vertheless, this explanation IMI com-accounted for the much smaller escape of iodine that was observed at pared to the amount predicted to escape if elemental iodide had been present, as is assumed in the Regulatory Guides.
We believe that this description can be strengthened and ende more definitive.
iodine Although the present data,are not absolutely conclusive, we believe that The reactor emerged from the fuel as cesium iodide, already reduced to iodide.
system environ =ent then sustained this chemical state.
Furthermore, it would have converted other iodine species, should they have been present, to iodide.
reached metal Cesium iodide would be expected to condense or " plate-out" when it temperatures at or below 400 to 500*C, and it would finally enter surfaces at into solution as iodide ion as soon as water or condensing steam was encoun-The reactions of iodine species in water, and the fact that iodide ion tered.
is the dominant species, ensure that iodine volatility will be very small A reaction (compared to that implied by the Regulatory Guides, for example).
causing oxidation of iodide would be necessary to increase the volatility of Additional experimental work is required to, provide a quantitative iodine.
description of_, lodine behavior, but this qualitative picture is consistent with the small escape of iodine observed in a number of incidents when water was pre-sent, such as at TMI.__--
This mechanism is, supported by the following observations. as _vell as by measurements made_,at IMl:
Iodine and cesium are released congruently from' PWR leakers during power 1.
transients (the iodine spiking phenomenon).
Thermodynamic calculations performed at several sites indicate that CsI is
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the stable form of iodine *a IRR fuel.
Further, the fission yield of cesium is larger than that cf iacine, and cesium is always present in great (about tenfold) excess over iodine.
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Irradiated fuel has been caused to fail in experiments performed under simu-3.
lated accident conditions, and the iodine released is recovered predomi-nantly as CsI rather than as molecular I.
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The chemistry of iodine is such that, if water is accessible, 1odine vill interact with the water so that its concentration in the gas phase vill be
=uch s= aller than its concentration in the water.
5.
In other incidents that have led to the destruction of fuel in water syste=s (NKI, Spert-1, Snaptran-3, SL-1, M1"R, ORR, and pKTR), we understand that a
=uch s= aller a=ount of iodine escaped frc= the syste=s than vould be pro-i jected by the existing models.
Data are hard to co=e by for =any of these accidents and experi=ents, and our investigation is continuing.
In earked contrast, a large fraction (20,000 curies) of the iodine escaped to the environment during the Windscale accident, which occurred under oxidizing cdaditions and in the absence of water.
The significance of this mechanis: for iodine escape and transport can hardly be overe=phasized.
We assert that the unexpectedly low release of radiciodine in
, - the Dil-2 accident is now understood and can be generalized to other postulated accidents and to other designs of water reactors.
We believe that an accident involving hot fuel and a water or stea=-vater enviren=ent vill have the same De controlling che=ical conditions as did the DiI-2 core and pri=ary system.
iodine vill emerge as CsI (and possibly some other iclides) and enter into the solutun as soon as wet steam or, water is encountered.
It will persist in solu-tion as non-volatile iodide ion as long as oxidi=ing conditions do not prevail.
Although we feel that the evidence is sufficiently strong to justify this letter, it is i=portant to qualify our position.
Iodine chemistry is very complex, and definitive experimental and analytical studies of iodine behavior during and following lbss-of-t:oolant accidents are lacking.
Nonetheless, it is clear that the, behavior projected from the existing Regulatory Guides is wrong.
De current NRC assumption, that elemental iodine is the che=ical form of the radioiodine released, is regarded as a conservatism, but in this case the,
l a ssu=ption of a wrong"ebical form zust be regarded ~as an error which has com-pcanding effects. ~ ~
I If, af ter due consideration, 'he NRE is'datisfied that 51r description of it, Jins
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t behavior is valid, we reco==end that an urgent study and assess
-t be rade of all available inf ormation, and appropriate actions be undertake With due respect we point out four conseque.nces should our position be correct:.a 1.
he frequentl[ quoted fission" product escape assu=ptions ~ (from TIi)'-14 814 id
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l 1 %2 to the more recent Regulatory Guides 1.3 and 1.4, and the Reactor l
Safety Study, WASH-1400) should be reexamined.
he present assu=ptions grossly overstate iodine release from a reactor site in =any types of loss-of-coolant accide'nt, and safety criteria based on these assu=ptions should
.be reevaluated.
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Chairman J. Ahearne August 14, 1980 2.
The dispersal of radiciodine in the biosphere may no longer dominate and control consideration of accidents and the design of safety systems.
3.
Many, if not most, accident seque.nces r:ast be reexamined in detail.
The iodine risk to the general public may, in fact, be lower than previously l
esticated, possibly by orders of magnitude.
- Ihe i pact of a reduction of m
iodine risk on the requirements for evacuation is particularly important at this time.
4.
The engineered safeguards designed for iodi.se control should be reexamined to assure eff ectiveness and optimization for the actual iodine behavior rather than the behavior currentl'y assuned.
Finally, we realize that a rajor revision of NRC assu=ptions relative to acci-dent analyses, dose calculations, and design of safeguards should not take place without an adequate base of technology from both experiment and theory, and especially until the Commission itself is convinced that it is appropriate to accept a revised physical and chemical description of iodine transport from fuel to the environment.
On the other hand, the impact of wrong assunptions is so serious that an intensive effort should be made to establish the facts.
We are ready to" offer core detailed information or further as'sistance should the -
NRC request it.
We vill be pleased to brief the NRC staff or any review co==it-j tees you may oppoint.
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NUCLEAR REGULATORY COT.*!alSSION
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OCf 3 01980 MEMORNiDUM FOR: Distrioution FROM:
Walter F. Pasedag, Leaoer, Raciological An'alysis Section Accident Evaluation Brancn, OSI
SUBJECT:
MI!!UTES OF MELTIr:G WITH URS. STRATTON, I*.ALIllAUSKAS, Afiu CAMPBELL In response to a letter to Chaiman Ahearne dated August 14, 1980, by Ors. W. R. Stratton, A. P. Malinauskas and D. O. Campbell, the tiRC staff invited the authors to discuss the content.and bases of their letter.
A meeting was held for this purpose at'9:00 A.M., October 22, 1980 in room P-il8 at the Phillips Building.
The first presentation was given by Dr. A. P. Malinauskas. Dr. Malinauskas' main topic was the chemical form of iodine in.the fuel rod and during it's release from the fuel during an accident. Dr. Malinauskas reviewed several His themodynamic and post-irradiation fission product release studies.
i emphasis, however, was on the Gap Purge Experiments by Lorenz, Jsborne, C)llins, and Malinauskas. These experiments involved fully irradiated fuel e?ements from the H. B. Robinson and Peach Bottom plants.
In these experi-melts, iodine released from the fuel gap during heating (up to a maximum ci about 16000 C) 'was deposited.along with Cesium i. a thermal gradient tube at temperatures between 200 and 9000 C, indicating that the iodine fom could not have been elemental iodine vapor, but, most likely, was cesium iodide.
Malinauskas also mentioned obserhations of concurrent release of small quantities of cesium and iodine into the primary cooling system during normal operation (" iodine spiking phenomenon").,
In his review of previous experiments, Malinauskas acknowledged that the release of 1 trom LWR fuel was observed, but noted that such releases occurred when the carrier gas included air (intentionally or unintentionally).~
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Another possibility for compromising results can arise from the use of l
quartz in high temperature test apparatus, which can lead to the formation This reaction, as well as possible air ingress of cesium silicates and I.
2 were postulated to have invalidated the results of Castleman et ai (1965-1967),
who observed elemental iodine releases in steam atmospheres. Similar problems l
were postulated for experiments conducted in the United Kingdom and Japan.
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l Malinauskas concluded that iodine resides in the fuel as an iodide, which cost likely is CsI, not in the volatile elemental fonn.
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Hinutes ci :).uting of October 22, 1939 OCT 3 0 L;30 Dr. Campbell followed with a presentation of iodine chemistry in an aqueous environment. He reviewed the chemical species identified in the literature, and discussed the significant volatile species, i.e. molecular iodine (1 organic iodides, and other species with some state of positive valance, 2),ined hypoiodous acia (Hul) by some investigators,.although the ter existance of the latter form has never' been conclusively proven. He quoted the authoritative work of A. Eggleton, who calculated iodine volatility based on data available in the literature (1967), which he presented in the form of " partition coefficients."
Campbell then discussed the iodine chemistry following the TMI-2 accident.
He noted that he believed the value quoted for the iodine concentration (on 4/1/80) in the Kemcny report to be in error by an order of cagnitude.
The partitio'n coefficient expected at TMI if the iodine were released as 2 was 5 x 10, which would put about 0.1% of the iodine released into the 4
1 Actual measurements, however, were stated to be lower by about gas phase.
a factor of 10, i.e. 0.007% according. to the ' sample taken on 3/31/79. Sump water samples, however, contained a substantial amount of copper (of uniden-tified origen), as well as iron, nickel, aluminum, and calcium. The copper and iron of the' sump water sa ples was largely reduced cuprous and ferrous oxides, indicating that any iodine in the sump water would have to exist as iodide. Thus, Campbell concluded that the water in the TMI reactor building was strongly reducing, and, therefore, essentially no oxidation of iodide occurred.
Campbell concluded with a discussion of organic iodides and radiation effects on iodine chemistry. He stated that, although predominant in the pre-purge atmosphere at TMI-2, organic iodides, cs a total, ccnstitute a very small fraction of the iodine introduced into the containment. Concerning radiation effects, he noted C. C..Lin's finding that the OH radical oxidizes iodide, which react further to form iodate at low concentrations, but concluded that He concluded that organic iodide fonn,uct under realistic accid is not a significant reaction prod 12 ation will be lower than that predicted by.Postma and Zavadoski (WASH-1233), since little.I2 is postulated to per-severe in the containment atmosphed......
Ur. Stratton concluded the' presentation witFa discussion of past experience with accidents involving a substantial release of fission products,. ranging.. _ r from the IJRX accident in 1952 to.the TMI-2 accident in-1979,,.-Ne divided accidents into two categories, i.e. those with a reducing-environment, and.
those with an oxidizing environor.nt _.._.
In addition to the flRX reactor accibei$t, Strakton listed Sf!AP, SPIRT, SL1, ETR, and PRTR as examples.of accidents with reducing environments,.and noted.
that no iodine was released.in these accidents. with the exception of a minor.
release (0.5%).,for the SL1 accident.
In contrast to thIse accidents, Stratton noted substantial iodine releases in the Windscale and NRU reactor accidents, and the Heater 3 experiments in 1958.
Stratton stated that the group strongly recommends' that the fiRC establish a task force to examine fission product behavior.
Minutes of. acting of October 22 E3 DGT 3 0 650 Questions by the staff were invited during and following these presentations.
In response to staff questions, Malinauskas emphasized that the stated con-clusions were not applicable to those accidents in which the fission products are released into an atmosphere containing air. Stratton stated that their remarks were intended to address those accidents where containment integrity is maintained.
Stratton also clarified that the phrase " current fiRC models" contained in the August 14 letter referred to Regulatory Guides 1.3 and 1.4.
The staff pointed out that fiRC's c0rrent regulatory models are not restricted to Reg. Guides 1.3 and 1.4, and that the iodine partition' coefficient models of Eggleton are used by the staff to evaluate the behavior of iodine in aqueous environments.
Other staff comments emphasized the regulatory philosophy, that the design basis accident analyses, as reflected in Reg. Guide;1.3 and 1.4, and TID-14844, was not intended to be a realistic treatment of accidents, but.an intention-ally conservative treatment of a hypothetical " design basis" event. The three authors of the August 14. letter agreed that the Reg. Guide 1.3 and 1.4 assump-tions were indeed conservative, but.noted that this conservatism distorts the actual risk to the public as perceived by them.
The meeting concluded with an expression of the staff's appreciation of the willingness of Drs. Stratton, Malinauskas, and Campbell to elaborate on and discuss with the.flRC staff the content and basis of their August 14 letter to Chairman Ahearne.
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NOTE TO: Thomas E. !!urley, Director Division of Reactor Safety Research FROM:
R. R. Sherry Experimental Advanced Safety Technology Branch -
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SUBJECT:
RESEARCH PROGRAMS RELATED TO IODINE RELEASE AND TRANSPORT UNDER ACCIDENT CONnITIONS~
i This note summarizes our current and planned research programs which provide information related to understanding iodine species behavior (in particular CsI) under accident conditions.
As you are aware, NRC regulatory assumptions related to iodine behavior s
(within containment) assume the existence of only three physiochemical forms of iodine - molecular (91 percent), organic (4 percent), and particulate (5 percent).
However, since about the time of the RSS, a number of investigators have become concerned that the principal form of iodine released under LWR accident conditions may not be 1, but CsI.
2 The following paragraphs describe our current and planned research programs which address this question.
Fission Product Release From Defected LNR Fuel - ORhl This program, which was completed last year, has provided most of the evidence which exists on the chemical forms.of fission products released from fuel rods under LWR accident conditions.
Under this program, equilibrium thermodynamic calculations, separate effects tests, and heating tests with segments of commerciallyiirradiated fuel rod segments
. have provided evidence indicating that the principal iodine chemical species released from defected fuel rods into a steam environment is Cs!.
I Secarate Effects Tests for TRAP Code Development - Sandia 7
The purpose of this program is to measure the vapor pressure of important fission product species at elevated temperature and to investigate the chemical reactions betw'en fission products and (1) steam (and H ), (2)
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2 prototypic RCS surfaces, and (3) other fission products under high 9
temperature (Tmax = 1000*C) conditions. Tests, so far, using Cs1 have indicated that Csl is stable at temperatures up to approximately 800*C in nitrogen / steam and nitrogen /H2 gas mixtures and does not readily react with stainless steel or nickel surfaces.
I have asked Sandia to investigate the high temperature
- stability of Cs! in N /02 and N /H 0/02 2
2 2 environments. They plan to do this in the near future.
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Thomas E. Murley SEP 1 2 133C Fission Product Transoort Analysis - ECL The TRAP code is currently capable of modelling steam phase Csl transport within the primary system (although in the past iodine was assumed to be in elemental form for calculational exercises - e.g., sensitivity studies.
It can be expected that TRAP calculations will show that when iodine is in the form of Csl the amount of iodine condensing on primary system surfaces and " washing out" within the RCS will be significantly4arger than if the assumed chemical form for iodine is 1.
In addition, Cs!
2 that does not condense on a system surface may nucleate (or condense on other particies) to form aerosols. Hence, the iodine form in the con-tainment atmosphere under accident conditions may be primarily particu-late Cs! (assumming the CsI is not oxidized upon entry into containment) rather than elemental iodine.
Fission Product Release from High Temaerature Fuel - ORNL In this research program we plan to investigate fission product release frcm LUR fuel rods into a steam environment under severe core damage and core melt temperature conditions (1000*-2800*C). As part of this program, methods (e.g., laser Raman spectroscopy) of deterrining the chemical form (s) of fission products released from the rods will be investigated.
Fissior. Product Transoort Verification Facility - Undesignated Plans are currently being developed to ccnduct integral experiments for validating the large fission product transport codes (e.g., TRAP-MELT, CORRAL, CONTAIN, etc.).. In this program (to be conducted in the ORNL/NSPP and/or HEDL/CSTF facilities), it will be possible to determine the transport behavior of Csl under large-scale, near-prototypic conditions and to determine if our current computer models are, adequate for describ-ing the transport behavior of CsI.
Iodine and Tellurium Behavior Under Accident Conditions - ORNL ;
The purpose of this research (which is part of Don Hoatson's coolant chemistry program) is to~ investigate the chemical species of iodine and..
tellurium during' vapor phase and liquid transport.in RCS or containmente e_
aqueous solutions as_a functio.n of the local thermo-chemical-. conditions.,_
(chemistry, temperature ~, pressure, etc.).
This program will include a determination of_ the partitioning of these species between the liquid and vapor phases.
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3-SEP 1219D Thomas E. Murley Fission Product Source Term Definition for Degraded Core Cooling Conditions -
ORNL The Office of Standards Development has recently requested that RES initiate a short term (< 1 year) program to develop fission product source terms for accidelits more severe than a design basis LOCA to aid OSD in developing regulatory guides in the areas of biological shielding iequirements for fluid systems which penetrate containment (e.g., ECC, letdown) and for preparing interim recommendations for degraded core accident analysis source terms. The primary objective of this effort will be to review and evaluate the existing fission product release and transport data base and to generate source terms applicable.to a range of degraded core conditions, accident scenarios, and potential transport pathways. An important aspect of this program will be to provide real-istic source terms for the volatile fission products (noble gases, io' dine,andcesium).
NC R. R. Sherry Experimental Advanced Safety Technology Branch Divisicn of Reactor Safety Research u.--
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Suggested Agenda Release During Accidents Commission Meeting on Fission Product 18, 1980 November 10:00 A.M.
Iodine Release During Accidentslinauskas and Campbell:
I.
Presentation by Drs. Stratton, Ma 14, 1980 letter Synopsis of technical bases for their Aug.fety, margi 1.
a)
Impact of the perceived excessive sa b) releases Presentation by F. von Hipple 2.
Staff Response to Question 3.
2:00 P.M.
t Estimates of Consequences of Acciden s tives:
Presentations by industry representa II.
1.
C. Starr, M. Levinson, I. Wall Comments by De W ikarski 2.
Presentatic as by Dr. H. Kouts 3.
i Comments by the Staff irements (NRR)
Potential Impact on Regulatory Requ ce Spectrum (RES)
III.
Impact on Core Melt Accident ConsequenIodine Rele 1.
2.
NRC Research Programs Related to 3.
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