ML20027C885
| ML20027C885 | |
| Person / Time | |
|---|---|
| Issue date: | 08/11/1982 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-2009, NUDOCS 8210270378 | |
| Download: ML20027C885 (19) | |
Text
DATE ISSUED:
8/11/82 MINUTES OF THE QCRS~AM9 ACRS SUBCOMMITTEE MEETING ON THE SAFETY RESEARCH PROGRAM JULY 7,1982 WASHINGTON, D.C.
INTRODUCTION The ACRS Subcommittee on Safety Research Program held a meeting on July 7, 1982 at 1717 H Street, N.W., Washington, D.C. to continue its discussion on the NRC Safety Research Program and budget for FY 1984 and FY 1985.
The entire meeting was open to public attendance.
Mr. Sam Duraiswamy was the Designated Federal Employee for the meeting.
A list of documents submitted to the Subcommittee is included in Attachment A.
ATTEhDEES ACRS:
C. P. Siess (Subcommittee Chairman), J. C. Mark, D. A. Ward, D. Okrent, P. G. Shewmon, M. Bender, M. W. Carbon, W. M. Mathis, M. S. Plesset, J. J. Ray, and S. Duraiswamy (Designated Federal Empl oyee).
Principal NRC Speakers:
R. Minogue, F. Gillespie, O. Bassett, F. Arsenault, L. Shao, K. Goller and G. Knighton.
EXECUTIVE SESSION Dr. Siess, the Subcommittee Chairman, convened the meeting at 8:40 am and indicated that the purpose of the meeting was to continue discussion of the NRC Safety Research Program and Budget for FY 1984 and FY 1985, and also to discuss a draf t ACRS report to the Commission on the related matter.
He said that the Subcommittee had received neither written comments nor requests for time to make oral statements from members of the public.
Dr. Siess said that the Subcommittee would first hear a presentation from the Office of Nuclear Regulatory Reseasrch (RES) with regard to the current status of the NRC Safety Research Program budget for FY 1984 and FY 1985, and also the changes made to the NRC Safety Research Program subsequent to the June 2,1982 ACRS Subcommittee meeting on the Safety Research Program; then, it would discuss the input provided by various cognizant ACRS Subcom-mittee Chairmen for the ACRS Report to the Commission.
8210270378 820811 PDR ACRS 2009 PDR
e-Nuclear Safety Research Program July 7, 1 982 PRESENTATION BY THE RES - DR. R. MIN 0GUE Status of FY 1983 NRC Safety Research Program Budget Dr. Minogue said that the F.Y 1983 budget for the NRC Safety Research Program has not yet been appropriated by the Congress.
There are some differences of view, such as LOFT, among the Congressional Committees and they are being discussed at the House / Senate Conference Committee.
Although he believes that there is generally strong support in the Congress for the level of fund-ing requested for the NRC Safety Research Program, he is not sure what the final outcome will be.
Significant Changes made to the NRC Safety Research Program and Budget Since the June 2,1982 ACRS Subcommittee Meeting on the Safety Research Program Dr. Minogue said that the following changes have been made to the NRC Safety Research Program and Budget subsequent to the ACRS Subcommittee meeting on the Safety Research Program on June 2,1982:
1.
The costs for the LOFT Consortium have been included with a corresponding increase in the total budget for the NRC Safety Research Program.
2.
Semiscale MOD-5 program has been included as a separate line item under the Decision Unit on Thermal Hydraulic Transients.
With regard to the LOFT Consortium, Dr. Minogue said that if the Department of Energy (DOE) is successful in establishing an international LOFT Con-sortium, NRC as a Consortium member would provide a funding support of
$10 million per year for three years; half of this funding would be in exchange for DOE assuming responsibility for decommissioning with appro-ximately $5 million per year for an actual NRC test program.
He indicated that although there may be some efforts by certain Consortium members to carry out the LOFT Consortium more than three years, NRC has not made any commitment beyond three years.
He mentioned that the Office of Nuclear Reactor Regulation (NRR) has already identifed some specific tests for the LOFT Consortium.
Mr. Bender asked what type of tests were proposed by NRR for the LOFT Consortium.
Dr. Minogue responded that NRR has proposed some small-break transient tests.
Nuclear Safety Research Program July 7, 1982 In response to a question from Dr. Siess, Mr. Bassett said that the LOFT Consortium may begin sometime in the middle of FY 1983 and end in the middle of FY 1986, assuming that it will not be extended beyond three years.
Dr. Mark asked about the difference between the nuclear-heated facility and the electrically-heated facility.
Dr. Plesset said that there has been some concern that the power distribution from the electrically-heated rods is not well controlled; however, he believes that the existing analytic capabilities are sufficiently mature to correct for differences between electrically-heated rods and nuclear rods.
He added that the nuclear-heated facility in more expensive than an electrically-heated facility.
In addition, the cost to run a test as well as the time betweer, tests are more in a nuclear-heated f acility than in an electrically-heated facility.
Dr. Siess asked whether there is an estimate for decontamination and decommissioning of LOFT.
Dr. Minogue responded that it depends on the level of contamination of the facility.
If the facility is clean as it is presently, it may cost about $15 million; if it is contaminated more after the final test, then the cost for decontamination and decommissioning will be significantly higher.
Dr. Minogue mentioned that the strongest support for the LOFT Consortium comes from the Federal Republic of Germany (FRG) and the United Kingdom.
He informed the Subcommittee that one of the issues being faced by the LOFT Consortium Group is the test matrix.
A representative from the FRG recommended a series of tests to look at fuel damage; however, NRC does not believe that running fuel damage tests in the LOFT is very practical and feasible.
This issue is being evaluated by the Consortium Group.
He believes that if an agreement on the test matrix is not reached, the LOFT Consortium may not be formed.
Nuclear Safety Research Program July 7, 1982 With regard to the Semiscale MOD-5 Program, Dr. Minogue said that its main objective is to obtain necessary information to validate codes that are used to study certain issues associated with the B&W reactors (Attach-ment C, pages 182).
He discussed briefly the estimated total cost and the schedule for the Semiscale MOD-5 Program (Attachment C, page 3). The total estimated cost for the MOD-5 facility is about 526 million; forty percent, about $10.4 million, of the total cost is expected to be provided by the NRC over a three year period (FY 1983 - 52.8 M, FY 1964 - 55.2 M, FY 1985
- 52.4 M) starting from FY 1983. The industry is expected to fund the remaining sixty percent, about $15.6 million, of the total cost.
He said that the NRC portion of the funding would be obtained by a reduction in effort in the following Decision Units (Attachment C, page 4):
- Waste Management (54.1 M)
- Risk Analysis ($2.0 M)
- Advanced Reactors (51.8 M)
- Thermal Hydraulic Transients (50.9 M)
- Accident Evaluation and Mitigation (51.6 M).
Dr. Siess asked whether they plan to build a new building for the MOD-5.
Dr. flinogue responded that one of the proposal is to modify the existing Semiscale building as necessary and use it for the MOD-5 facility.
i Dr. Minogue discussed how the funding for MOD-5 would impact certain programs such as Waste Management, and Damaged Fuel in the Accident Evaluation and i
Mitigation Decision Unit (Attachment C, page 5).
Dr. Okrent asked whether RES has defined the questions to be answered in the l
Damaged Fuel area.
Dr. Minogue said that the following questions have been formulated (Attachment C, page 6):
I 1.
How accurate / applicable are the current fission product source term data base /models for describing realistic accident be-havior?
1
Nuclear Safety Research Program July 7, 1982 2.
How good are our current estimates of hydrogen source term and timing of release?
3.
What is the magnitude and timing of fuel-behavior-induced loads on containment?
4.
Under what conditions is damaged core debris coolable?
Dr. Okrent asked how and what regulatory approach will be affected by the experimental program associated with the hydrogen source term.
Dr. Minogue responded that the existing regulation requires that analysis related to hydrogen should be performed based on 75 percent metal / water reaction; this percentage may be higher or lower for some accident sequences. He believes that the planned experimental program may provide some additional infonnation on this issue.
Further, it will also proviae information necessary to validate the codes that are used to characterize the system behavior under severe accidents.
Dr. Okrent commented that, in view of the fact that there is a wide range of accident scenarios, he does not believe that the experimental program intended to look at a specific scenario is going to provide information necessary for the decisionmaking process.
Dr. Shewnon said that experiments may help to decide which accident scenario should be looked at.
Dr. Siess asked whether the experimental program on hydrogen would provide information to determine the probability of reaching an upper bound on hydro-gen.
Dr. Minogue responded that this program would not help to determine the probability; it would help to validate the codes used in analysis associated with hydrogen.
Indicating that the ACRS as well as the NRR do not seem to support the expensive experimental programs in the Damaged Fuel area, Dr. Siess asked who is actually supporting these programs and why? Mr. Burdick from the Division of Risk Analysis of RES responded that the risk analysis group needs the information on the production of hydrogen to assess the possible
Nuclear Safety Research Program July 7, 1982 damage to the containment.
He added that they will have more confidence in the results of an analysis performed by using a code that has been developed on the basis of some experimental data than in the results that were obtained by using a code that was based on non-experimental data.
Dr. Okrent commented that he is not convinced that the need for such expensive experimental programs in the Damaged Fuel area has been adequately justified.
He does not believe that these programs will provide the information necessary for the decisionmaking process in this area.
Dr. Mark commented that since the main concern is to get rid of the hydrogen as soon as it is generated, he believes that the NRC Staff should concentrate on assuring themselves that the hydrogen generated under accident conditions could be burned without affecting the containment integrity; he does not believe that they need to have validated codes to determine rate of hydrogen generation.
With regard to the research in the Advanced Reactors area, Dr. Mark commented that it is a mistake for not including any research associated with the post CRBR-LMFBRs.
Dr. Minogue responded that the decision has been made by the Commission to limit the research only to support the CRBR licensing activities.
He believes that such a decision is based on the uncertainty associated with the Administration's view on this issue.
Should a broader national LMFBR program appear likely for initiation, the NRC would reconsider the question of future LMFBR research.
Dr. Okrent and Dr. Siess commented that although we have about 500 reactor years of experience with LWRs, we are still spending about $200 million per year for research associated with LWRs; it seems that we may have to wait to gain that much experience with LMFBRs prior to doing research in that area.
Dr. Minogue discussed briefly the nature of comments received from the research user of fices and how RES factored those comments in the FY 1984
- 1985 budget development process ( Attachment C, page 6).
He said that RES has either accommodated all of the NRR technical comments or have
Nuclear Safety Research Program July 7, 1982 reached some common ground on issues where they have some difference of opinions.
However, in the Seismology / Geology area, NRR has not yet endorsed the expanded research program developed by RES.
With regard to the comments from the Office of Nuclear Material Safety and Safeguards (NMSS) and the Office of Inspection and Enforcement (l&E), Dr.
Minogue said that RES has incorporated essentially all of their comments.
He mentioned that NMSS has submitted a new prioritized program list for Safeguards research and it is being discussed by RES and NMSS Staffs.
Dr. Okrent asked at what level the program to look at design features to minimize the sabotage has been funded?
Mr. Goller responded that it is funded at about $0.35 million per year starting with FY 1983.
Dr. Okrent commented that although the program in the Damaged Fuel area is not defined well, the Staff has been spending about $15 or more million in that area.
However, it is not clear to him why they intend to spend only about $0.35 million to look at design features to minimize the sabotage.
He is not sure how the relative importance of various issues has been decided by the RES.
Dr. Minogue responded that in his opinion sabotage is only one possible l
initiating mechanism of common cause failures.
They have a substantial ef fort in the Severe Accident Research area to look at all of the common cause failures.
Dr. Okrent commented that he does not believe that all of the initiating mechanisms to common cause failures can be treated in a same manner. Common cause failure due to sabotage involves different thinking than that due to maintenance or design errors.
He asked what kind of research has been done so far to identify design features to reduce the likelihood of a sabotage fran insiders or outsiders.
Mr. Goller responded that research has been done to identify design features for new plants to minimize the potential for and consequences of sabotage.
Research was also done to identify necessary modifications in the existing
Nuclear Safety Research Program July 7, 1982 plants to minimize or prevent the likelihood of sabotage.
The results of these research programs are expected of very shortly.
They plan to evaluate these results and determine whether the design measures identified are cost effective and if so how they should be implemented. He mentioned that there is also a rulemaking effort underway which would include require-ments for design to minimize the possibility of sabotage.
Dr. Okrent asked whether RES thinks that enough research has been done in the sabotage area.
Mr. Goller responded that until they evaluate the re-suits of the research that has already been done in this area, they cannot decide whether additional research is necessary.
Dr. Mark requested a copy of the report based on the research in the Sabotage area.
Mr. Goller said that he will send a copy to Dr. Mark, in response to a question from Dr. Siess with regard to the Technical Assistance Program (TAP) activities, Dr. Minogue said that they do not have any definitive criterion to decide which research should be carried out under the TAP.
Further, he does not believe that there is a need for a specific criterion for TAP research; most of the research done in this area is short term and aimed at answering specific licensing questions.
He believes that there is no duplication between research performed by RES and TAP research done by research user offices.
Mr. Knighton, NRR, added that NRC procedures require that any TAP research with a funding level of $100,000 or more should be reviewed by all of the NRC offices i
to avoid duplication, t
l Dr. Siess asked how much money NRR and NMSS are spending for TAP activities.
l Mr. Gillespie said that NRR has a funding level of about $40 million and NMSS has about $17 million for TAP activities.
Dr. Carbon asked whether there is a program to perform probabilistic risk assessment of CRBR.
Dr. Minogue responded that although RES has proposed a program in this area with a funding level of about $0.35 million in FY 1982 and $1.2 million in FY 1983, NRR has not yet endorsed that program.
Nuclear Safety Research Program July 7, 1982 RES is still discussing this issue with NRR.
If it is not resolved, RES may self endorse this program.
DISCUSSION OF THE DRAFT ACRS REPORT TO THE COMMISSION ON THE NRC SAFETY RESEARCH PROGRAM BUDGET FOR FY 1984 AND 1985 The Subcommittee discussed several issues such as the following prior to reading the draft chapters of the ACRS report to the Commission:
- Format for the ACRS report to the Commission.
Items to be included in the General Comment Section of the report.
- Adequacy of the overall NRC Safety Research Program support budget for FY 1984 and FY 1985.
- ACRS priorities and reallocation of funding for certain research dreas.
- PBF, ACRR, and NRU experimental programs.
- LOFT Consortium.
- Semiscale MOD-5 program and the appropriateness of the source of funding for this program.
Based on its discussion of the above items, the Subcommittee has decided to recommend the following to the full Committee:
- For FY 1984, endorse the total funding of $209.5 million recommended by the ED0 with some reallocations and reemphasis based on ACRS priorities.
The Subcommittee was not able to reach any conclu-sions with regard to reallocations of funding for certain re-(
search programs with the exception of the following.
It decided to pursue discussion of this matter with the full Committee:
- Increase the funding for the Advanced Reactors Decision Unit by $1 million per year for both FY 1984 and FY 1985 to support a probabilistic risk assessment study of CRBR.
L
Nuclear Safety Research Program July 7, 1982
- Increase the funding for the Facility Operatings Decision Unit by $1.5 millon per year for both years to support additional research in the Human Factors, and in the Sabotage areas.
- With regard to the total funding of $195 million for FY 1985 recommended by the EDO, the Subcommittee felt that it does not seen appropriate to request lesser funding for FY 1985 than for FY 1984.
The Subcommittee felt that, although some of the existing programs will be completed or greatly reduced in size as research objectives are reached, it seems highly likely that new questions will arise between now and the beginning of FY 1985. On this basis, the Subcommittee decided that the total funding for FY 1985 should be increased.
However, it did not decide how much increase should be recommended.
It decided to pursue this matter with the full Committee.
- Do not endorse the experimental programs in PBF Phase 11, NRO, and ACRR.
- Any additional spending on LOFT is not appropriate; continuation of the LOFT Program will not be cost effective and therefore, do not support NRC participation in the LOFT Consortium.
- The Subcommittee decided to recommend that the proposed Semiscale MOD-5 facility be made available as soon as possible for the simulation of B&W reactor configuration so as to aid NRR to perform its required regulatory functions for this f amily of reactors.
The N00-5 facility should be located at the Idaho National Engineering Laboratory so that the program can profit from the significant experimental and theoretical experience already gained with other versions of Semiscale.
With regard to the funding support for the Semiscale MOD-5 program, the Subcommittee decided to reiterate, the previous ACRS recommendation
Nuclear Safety Research Program July 7, 1982 that the NRC seek significant financial contribution from the indu stry.
The Subcommittee felt that it does not seem appropriate to reduce certain important research programs in FY 1984 to provide for the NRC portion of the funding of $5.2 million for 140D-5.
It thought that all of this funding should be taken from the Damaged Fuel program included in the Accident Evaluation and tiitigation Decision Unit.
- In view of the understanding that NRR does not endorse a proposed program under SStiRP to perform a probabilistic seismic safety study of a BWR, the Subcommittee decided to reiterate the previous ACRS recommendation that such a study be included.
- The Subcommittee felt that since the modification of Appendix K is not completely the responsibility of RES, it would be oetter to write a separate letter to the Comission including ACRS views on this issue.
The Subcommittee read the draf t chapters and/or sections ' the ACRS report l
to the Commission provided by the various cognizant Subcommittee Chairmen.
l It suggested some changes, additions, and deletions and indicated that another l
draf t should be prepared incorporating the coments and suggestions provided by the Subcommittee for discussion at the full Committee meeting on July 8, I
1982.
Dr. Siess thanked all participants and adjourned the meeting at 5:20 p.m.
I i
Additional meeting details can be obtained from a transcript of this meeting available in the NRC Public Document Room,1717 H Street, N.W.,
Washington, D.C., or can be purchased from Alderson Reporting Company, l
Inc., 400 Virginia Avenue, S.W., Washington, D.C. 20024, (202) 554-2345.
Saf ety Researcn Program Meeting July 7, 1982 LIST OF DOCUMEjiTS,,S,UBMMITTED TO THE SUB_CoyfilTTELL 1.
Current Status of the FY 1964-1935 f4RC Safety Researcn Program Budget, R. Minogue, dated Juif 7, 1982.
2.
RLS Responses to tne ACRS General Conments and Recommendations delineated in fiURLb-OS64 AlTACHMLNT A
(k) p
,m, 06/10/82 NUCLEAR REGULATORY RESEARCH FY 1984-85 BUDGET (DOLLARS IN MILLIONS)
FY 83 FY 84 FY 85 FY 82 CONG.
REQ RE0 REACTOR / FACILITY SAFETY REACTOR & FACILITY ENGR.
$ 33.1
$'37.0
$ 40.5
$ 42.8 FACILITY OPERATIONS 13.0 13.5 16.8 17.1 THERMAL HYDRAULIC TRANSIENTS 16.3 21.7 27.5 22.6 i
SITING & HEALTH 9.3 9.0 11.0 11.7 RISK ANALYSIS 16.0 15.9 19.3 22.2 TOTAL
$ 87.7
$ 97.1
$115.1
$116.4 REACTOR ACCIDENTS l
ACCIDENT EVAL. & MITIGATION 33.1 47.2 45.4 38.6 LOSS OF COOLANT ACCIDENTS 14.6 11.1 10.5 9.2 LOFT 42.0 15.0 17.5 10.0 TOTAL 89.7 73.3 73.4 57.8 ADVANCED REACTORS 7.5 12.7 9.5 8.5 WASTE MANAGEMENT 11.9 12.1 11.9 12.3 TOTALPROGRA.kSUPPORT
$196.8
$195.2
$209.9
$195.0
.m z-=-
=_ x w _.__'
plinpfMF OF RFMisrAIF MnDS DFKIGN (TWO LOOP BY FOUR PUMP INTEGRAL SYSTEMS TEST FACILITY)
NEEDS IDENTIFIED FOR B&W AND CE DESIGNS:
1.
B&W - PREDICTED CYCLIC BEHAVIOR WITH TWO-PHASE MIXTURE IN NATURAL CIRCULATION.
2.
BtW - REACTOR VESSEL - EFFECT OF DOWNCOE R VENT VALVES
\\
UNDER ACCIDENT CONDITIONS.
t N
3.
B&W - STUDY EFFECTS OF SECONDARY SIDE UPSETS ON PRIMARY i
SYSTEM.
t 4.
CE - EVALUATE EFFECTS OF STOPPING OE PUFF IN EACH LOOP WITH SBi.0CA.
l l
h TracusoErtT C e1
e 4
FYK RIE NTAI FACIIITY IFRIEN CRITFRIA 1.
SCALE POWER TO VOLl#E RATIO 0F BsW NSSS.
2.
PRESERVE ELEVATIONS.
3.'
REPRESENT BtW DESIGN FEATURES:
VENT. VALVES AND H0T LE6 CANDY-CANE.
i CAPABILITY TO REPRESENT EITER BtW RAISED-LOOP OR LOWER 4.
s.\\
LOOP DESIGN.
\\
5.
CAPABILITY OF REPRESENTING EITHER ONCE-THROUGH OR U-TtBE i
6.
PROVIDE THE ABOVE WHILE RETAINING CAPABILITY TO REPRESENT XEY THERMAL HYDRAULIC PHENDENA.
(
o C -p
9-SEMISCALE N005 l
I Design I
l n " 11-Procurement g
I I
81dg Prep i
l s Factitty Coast i
1 i
IRst Check out s
i
$M 15 -
(13) 10 -
(7)
TOTAL COST (5.2)
(6) 5-(2.8)
NRC COST (2.4) e-3 I
O i
i i
FY 1983 FY 1984 FY 1985 d
l n
JULY 1982 l
SEMISCALE MOD 5 REDUCTIONS TO RES FY 1984-1985 g
r l-JUNE BUDGET SUBMISSIONS TO FUND MOD 5 l
l l
FY 1983 FY 1984 FY 1985 WASTE MANAGEMENT
$1.5
$1.5
$1.1 RISK 1.0 1.0 0
CRBR 0.3 1.0
.5 THERMAL HYDRAULIC IRANS!ENTS SEMISCALE
.8 CODES 0.'1 ACCIDENT EvAtuATioN & Mir:GArioN DAMAGED FUEL 1.4 IMPROVED SAFETY SYSTEMS 0.2 TOTAL
$2.8
$5.2
$2.4 L
2
O P
JULY 1]
RES PROGRAM IMPACTS TO FUND MOD 5 i
WAST,E, MANAGEMENT PROGRAM SLOWED WITH PRINCIPAL IMPACT TO REDUCE WORK ON PERFORMANCE i
AS,SESSMENT AND ON THE EFFECTS OF REPOSITORY CONSTRUCTION ON SURROUNDING ROCK.
CANCEL WORK ON NDT METHODS AND ALTERNATIVES TO SHALLOW bMD BURIAL.
RISK DEFER TO FY 1985 RISK ASSESSMENT OF MATERIALS FACILITIES AND UPDATE OF REACTOR RISK STUDY.
DELAY ACCIDENT SOURCE TERM HANDBOOK FOR FUEL CYCLE FACILITIES.
CRBR ADJUST RESOURCES TO USER NEEDS.
DAMAGED FUEL FuRTHER LIMIT IN-PILE FUEL DAMAGE EXPERIMENTS AS REQUESTED BY NRR.
SEMISCALE l
TRANSFER SEMISCALE SUPPORT PERSONNEL TO MOD 5.
l 2
Wf
't l
l
~
Q
( ~.,
OFFICE COMENTS
]
84-85 BUDGET I
Ell o WE flAVEiESSENTIALLY INCORPORATED ALL TECHNICAL C0tK NTS..
REQUESTED SPECIFIC INCLUSION OF SEMISCALE MOD 5 SUGGESTED AREAS FROM WHICH TO REDIRECT FUNDING IDENTIFIED AREAS OF CLOSE COORDINATION ESS REQUESTED AN INCREASED STAFFING LEVEL IN WASTE MNAGEENT (STANDARDS l
o SUPPORT)
STAFFING CONSTRAINED BY OFFICE PERSONNEL CEILING 0BJECTED TO COMPARING THE RISK OF FUEL CYCLE AND REACTOR OPERATIONS o
AND TO THE ASSUMPTION THAT EVENT TREE / FAULT TREE ANALYSIS WILL BE t
USEFUL IN LICENSING RESTRUCTURED PROGRAM TO DEEMPHASIZE RISK C0 FARIS0N AND EXPLORE ALTERNATIVES TO EVENT TREE / FAULT TREE ANALYSIS o SUBMITTED A NEW PRIORITIZED PROJECT LIST FOR SAFEGUARDS RESEARCH RES/NMSS STAFF DISCUSSIONS ARE ONGOING FOR RESOLUTION IE o WE HAVE INCORPORATED ALL COMMENTS
- SUGGESTED CURTAILENT OF DEVELOPENT OF ADDITIONAL REACTOR ACCIDENT
. SCENARIOS FOR EERGENCY PLANNING
/
p'(ep
_..