ML19242D004
| ML19242D004 | |
| Person / Time | |
|---|---|
| Issue date: | 07/31/1979 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | |
| References | |
| NUREG-0603, NUREG-603, NUDOCS 7908140343 | |
| Download: ML19242D004 (45) | |
Text
NU REG-0603 COMMENTS ON THE NRC SAFETY RESEARCH PROGRAM BUDGET July 1979
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Advisory Committee on Reactor Safeguards U. S. Nuclear Regulatory Commission 4
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N U REG-0603 COMMENTS ON THE NRC SAFETY RESEARCH PROGRAM BUDGET Manuscript Completed: July 1979 Date Published: July 1979 Advisory Committe on Reactor Safeguards U. S. Nuclear Regulatory Commission Washington, D.C. 20555 bb$
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E NUCLE AR REGUL ATORY COMMISSION ADVISORY COMMITTE E ON RE ACTOR SAFEGUARDS 2pjj
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July 19, 1979 The Honorable Joseph M. Hendrie Chairnan U. S. Nuclear Regulatory Commission Washington, DC
Dear Dr. hendrie:
The Advisory Committee on Reactor Safeguards (ACRS) is required to submit each year, prior to December 31, a report to the Congress on the NRC Safety Research Program. %e Commissioners have suggested that a simliar report would be helpful in their consideration of the budget for the Of fice of Nuclear Regulatory Research (RES) if received at an appropriate time. We attached report has been prepared in response to this sugges-tion.
This report includes comments on the budget levels and program plans for the supplemental request for FY 1980 to suppart research related to the accident at Three Mile Island, Unit 2 ('IMI) as well as for the FY 1981 Budget.
For both budgets, the funding levels considered by the ACRS are the original requests by RES and the Budget Review Group (BRG) markup as of July 10, 1979.
In the attached report the ACRS has given special attention to tuth the short-and long-term implications of the TMI accident.
The Committee expects to provide its annual report to Congress by the end of this calendar year taking into account the suggestions of H.R.
Report 96-194, Part 1.
Sinc ely,
/
W Max W. Carbon Chairman
Attachment:
NUREE-0603, " Comments on the NRC Safety Research Program Budget" - A Report to the: NRC from the ACRS 655 157
DREFACE The Advisory Committee on Reactor Safegu=rds (ACRS) is required to submit each year, prior to December 31, a report to the Congress on the NRC Safety Research Program. The Commissioners have suggested that a similar report vauld be helpful in their consideration of the budget for the Office of Nuclear Regulatory Research (RES) if received at an appropriate time.
This report has been prepared in response to that suggestion.
It includes comments on the budget levels and prcx] ram plans for the sunne-mental request for FY 1980 to support research related to the accideat at Three Mile Island, Unit 2 (TMI) as well as for the FY 1981 Budget.
For both budgets, the funding levels considered by the ACRS are the original requests by RES and the Budget Review Group (BRG) markup as of July 10, 1979.
In its current review of the NRC research program, the ACRS has given special attention to both the short-and long-term implications of the TMI accident and their significance to research for both the short-and long-term research programs.
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CONTEtES PART PAGE PREFACE ii 1.
IMPLICATIONS OF THE ACCIDEfC AT THREE MILE ISLAND, UNIT 2 -
1-1 1.1 Needs for New Directions in Research 1-1 1.2 Recommendations for New Directions in Research 1-3 2.
COMMEN"PS ON FY 1980 SUPPLEMENTAL REQUEST FOR T4I-RELATED RESENICH 2-1 2.1 Proposed Request 2-1 2.2 General Recommendations 2-1 2.3 Specific Comments 2-2 3.
OJMMENTS ON FY 1981 BUDGET 3-1 3.1 Introducti,n 3-1 3.2 LOCA-ECCS 3-1 3.3 Fuel Behavior 3-3 3.4 Primary System Integrity 3-4 3.5 Seismic Engineering Safety 3-4 3.6 Fast Breeder Reactors and Advanced Converters 3-7 3.7 Reactor Environmental Effects 3-9 3.8 Fuel Cycle and Waste Management 3-12 3.9 Safeguards 3-15 3.10 Risk Assessment 3-16 3.11 Improved Reactor Safety 3-18 65 i S c)
1.
IMPLICATIONS OF THE ACCIDENT AT THREE MILE ISLAND, UNIT 2 1.1 Needs for New Directions in Research One main lesson learned f rom the T4I accident is that a broader range of safety issues must be considered in planning the research programs of the future. Another lesson learned f rom TVI is that research must be carried out to provide answers to questions of two kinds:
(a)
How to prevent acciients like that at T4I-2; that is, accidents producing severe core damage short of core melting and accompanied by the release of large amounts of radioacLive material into the containment?
(b)
How to mitigate a T4I-type accident that results in even greater core degradation?
The TMI accident involved multiple " mistakes" and failures not now considered in the licensing procedure, and led to consequences not previously encountered.
Much of the activity by the NRC Staf f in the wake of T4I, and much of the TiI-related research proposed for FY 1980, relates to preventing "another TMI", chiefly by designing means to prevent the occurrence of similar mistakes or failures.
Once a mistake has been made or a f ailure has occurred, it is a rela-tively straightforward engineering task to devise means to prevent it from happening again.
It is more difficult to anticipate all, or even most, possible mistakes or failures.
This has been attempted in the regulatory process, but the method leans too heavily on the " single failure" concept and design basis accidents.
If means are to be provided to prevent multiple mistakes or failures, attention must be devoted to the sequences and consequences that could result from many different combinations of multiple mistakes or failures, two or three or five, or even six, as necessary to determine the possible interactions and their consequences, and to provide a basis for prevent-ing or greatly reducing the probability of their occurrence.
This was attempted in the Reactor Safety Study (WASH-1400) but for only two plants and, as learned from the T4I accident, both the kinds of mistakes and their consequences are dependent on the specific design of the nuclear steam supply system and of the balance of plant.
Although the results of the Reactor Safety Study emphasized the rela-tively great contribution to risk of transients and small loss-of-coolant accidents (LOCAs), few of the research requests showed a suitable degree of concern about future problems (transients and small LOCAs) as opposed to problans emphasized in the past, such as large LOCAs and ECCS e f-fectiveness.
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1-2 This situation must be remedied.
Many potential accident scenarios must be examined, and multiple miatakes and multiple rather than single failures must be postulated.
Suen research and its application in the licensing process may provide valuable insight about the problem of how to reduce the probability of TiI-type accidents. Such research need not, and probably should not, lead to nev design basis accidents.
- However, the results obtained should lead to new approaches in the design and licensing of nuclear plants.
The need to consider means to mitigate the consequences of a NI-type accident presents another challenge to the research program.
In this context, a TMI-type accident is considered one that results from a multiplicity of mistakes or failures, at a probability level which has been understated in the past.
If the WI accident involved the " highly improbable" combination of say five mistakes and/or failures, how improbable must we now consider six mistakes, or another sequence or combination of mistakes leading to significantly greater consequences than resulted at TMI?
Within this range of mistakes, it is possible to visualize a sequence leading to core melt rather than the deg ree of damage experienced at MI.
Although research is needed to learn how to prevent the occurrence of such an dCCident, as discussed above, research is needed also to understand its consequences and possible means of mitigating them. The fate of a molten core, whether it penetrates the reactor vessel and containment base slab and enters the ground below, and what happens to it and to the radio-activity it contains thereafter, in various geological and hydrological environments, ic poorly understood and has been studied only cursorily in comparison with the design basis accidents.
Little more is known about the possibility or probability of a steam explosion and its effect on the containment, the last line of defense -- the value of which was demon-strated so clearly at TMI.
Part 2 of this report contains recommendations regarding the FY 1980 Supplemental Budget Request to support, in part, additional research stimulated or required by the TMI accident.
Part 3 of this report contains recommendations regarding the FY 1981 Research Budget and research programs.
The ACRS recognizes that the NRC research program cannot be redirected overnight, nor should it be redirected completely.
Nevertheless, the lesson from mI is that new directions are required, at least in the areas of reactor safety.
Some changes in direction can and should be initiated in FY 1981, only 15 months frco now.
Other changes can be made in future years, but both the user and requester of research, as well as those @o approve, plan, and direct research, must begin now to think about and plan for the research needed to solve future problens before they present themselves.
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l-3 1.2 Recommendations for New Directions in Research In its review of the budget proposals in Parts 2 and 3 of this report, the ACRS has identified a number of areas in which the programs are not yet completely defined in content, but for which the need for research and funding is clear.
The following recommendations for new directions in the NRC Safety Research Progran are intended to provide guidance to the Commission, to the RES Staf f, and to the user of fices, that can be utilized in the detailed formulation of research prograns for FY 1980, to the extent practicable and for FY 1981, and for the development of requests and plans for FY 1982 and beyond.
The ACRS recognizes that research has already begun in many of these areas, and expects that others will be considered and implemented in a timely fashion.
The ACRS believes that this can and should be done without delaying the ongoing budgetary process.
1.2.1 Priorities and Focus The ACRS believes that the research and regulatory staff of the NRC should, in the reasonably near future, reevaluate the overall priorities, levels of expenditure, and focus of the safety research program.
The ongoing program to a large extent reflects priorities that were estab-lished several years ago and has been strongly influenced by the single failure concept and research needs arising from detailed studies of design basis accidents.
While useful results are being obtained from most ongoing research tasks, it is important that the Staff take a new broad look at the existing and recently proposed levels of support and research directions to evaluate the potential need for major change in emphasis.
The ACRS suggests that the existing structure of the safety research program, which was developed to manage a research program plan estab-lished a few years ago, be reviewed to determine whether modifications are appropriate to meet the requirements of the coming years.
Also, the ACRS notes that the focus of the research program has reflected the needs of the NRC regulatory staff as perceived in past years. Here, too, early attention should be given to an evaluation of the priorities of the detailed existing requests as well as requests arising from changed perceptions in safety research priorities.
1.2.2 Anomalous Transients and Small LOCAs The need for greater emphasis on transierits and small LOCAs has been recognized.
The ACRS recommended increased effort on transients in its 1977 and 1978 reports to Congress, and eraphasized the study of anomalcus transients in its Interim Report No. 3 on mI dated May 16, 1979.
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1-4 A research progran on anomalcus transients should have as its focus the need for greater understanding of the probable course of a wide rarge of possible events leading to severely degraded conditions, in order to provide a better basis for operator training, for improved instrumenta-tion, and for possible on-line computer-diagnostic procedures to aid the operator.
Equally, such studies nhould prcvide insight into the signifi-cance of possible design modifications and into areas of research warrant-ing further study in order to have an appropriate degree of preparedness and background knowledge, Such a program should receive coordinated guidance by a group including representatives from both licensing and research.
1.2.3 Accident Studies The NRC should initiate a series of analytical studies to explore the probable course of events and possible potential consequences of a broad spectrum of accidents which go well beyond the current design bases in terms of the damage to the core and the release of radioactivity to the environnent via both atmospheric and liquid pathways.
In particular, specific studies should be carried out to scope scenarios of serious accidents beginning from the initiating event through to the eventual resting place of a melted core for some of the sequences.
Preliminary guidance for the choice of scenarios to study can be provided by MSH-1400, although the TMI experience showed that many sequences must be considered altered by human intervention at some point.
For each scenario, sufficient technical detail should be provided to obtain insight into such matters as the following:
to what extent can the probability and consequences of the sequence be quantified; what are tne internediate stages in the sequence, and to what extent nay they be af fected by human intervention; how serious is the sequence in terms of its ef fects on human health; where are the trigger points for emergency action, and what are the criteria therefor; etc.?
It is especially important that these studies concern themselves with the identification of significant sequences that have not rcceived sufficient research attention, so that one can develop in advance significant safety procedures, and equipnent, and mitigating actions to avoid surprises of the sort that occurred at mI.
It is expected that such studies would be useful in the specification of instruments to help diagnose and follow the course of an accident, in the identification of new research and developnent needs, in siting consid-erations, in modification of containment, etc.
An ef fort on the order of ten man-years is envisioned.
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1-5 1.2.4 Molten Core Retention The NRC should undertake a conceptual study to examine the practicality of retaining a molten core within containment or significantly reducing the release of radioactivity via liquid pathways following penetration of the containment foundation, in order to help provide insight into the practicality, benefits and costs of such a safety feature.
1.2.5 Power Burst Facility The PDF program should be reoriented to emphasize primarily the study of the processes leading to medium and severe core damage in postulated accidents, the possible consequences of considerable molten fuel in the core, and possible measures to mitigate large scale core melt.
1.2.6 Steam Explosions The ongoing research program on steam explosions should be.substantially augmented to gain a better assessment of their potential role in various postulated accident scenarios, as well as possible insight into measures which could reduce the probability of a large scale thermal reaction, if such a reaction is possible.
1_.2.7 Siting A more extensive evaluation should be made of possible of fsite conse-quences via liquid pathways for postulated accidents involving core melt for a broad range of land-based sites whose characteristics are reason-ably representative of reactor sites in use, projected for use, or of potential interest in long-term planning.
Such an ef fort has already been initiated as part of the NRC research program.
The depth of the program should be sufficient to provide the background information needed for the possible development of hydrologic siting criteria which allow for the possibility and probability of accidents beyond those currently designed for.
A study should be made of the relative and absolute accident risks, with uncertainties, for a wide range of potentially suitable sites.
The study should examine the costs and benefits associated with different types of sites and should include the possible interaction of a serious accident in one reactor on other reactors at the site.
The intent of the study should be to provide insight into the relative advantages and disadvan-tages of more remote siting and power parks.
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1-6 1.2.8 Plant Operations A systematic effort should be made to identify research needs relating to the safety implications of procedures for operation, maintenance, testing and surveillance.
Operating experience should be reviewed to identify existing problems in these areas and to determine problems important to safety.
1.2.9 Transier.t Simulation in Research and Licensing Early consideration should be given to augmentation of the range of NRC capability to simulate various postulated transient and accident sequen-ces to varying degrees of sophistication, including but not limited to real time analysis and permitting a simulation of operator action and intervention.
Developnent of such simulation capability should enable a more detailed understanding of the course of events for various tran-sients, and would be useful in the developnent of improved operator procedures and training, diagnostic instrumentation, and computer-aided guidance to the operator.
1.2.10 Systems Behavior and Interaction A new research program should oe established in systems behavior and interaction w'alch includes ar interdisciplinary approach to safety research including electrical, thermal-hydraulic, mechanical, control, and heating, vertilating and air conditioning systems, under operational, transient and accident conditions.
Such a program should provide in-creased insight into the suitability of existing operational limits, the effect of systen arrangement on its ability to withstand abnormal tran-sient conditions, and the degree to which system design changes can be made to improve safety in one way without adversely influencing safety or reliability under other sets of conditions.
1.2.11 Application of Probabilistic Methodology The ACRS recommends emphasis on the applicatian of probabilistic and other methodology to an evaluation of the adequacy of the single failure criterion and to studies of alternate design approachec to systms and groups of systens important to safety in order to provide a better basis for decision making concerning the optimization of plant design for safety.
1.2.12 Water Specification and Crack Growth The Committee recommends that programs be initiated to develop appropriate water chemistry specifications, particularly in the BWR primary coolant c
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1-7 and Pa secondary coolant, and to establish the ef fect of environmental, fabrication, and operating variables on crack growth rates in the coolant systen boundary.
Cracking is a recurring problem and the NRC lacks a basis for establishing conservative practices to prevent it.
1.2.13 Distu.bance Analysis The ACRS recommends that both the licensing and research arms of the NRC Staff place considerable priority on the developnent of methods for real-time analysis of system disturbances, in an effort to provide improved diagnostic information to the operator concerning abnormal sequences and, as possible, to suggest favored courses of action.
The ACRS anticipates that the ef forts devoted to the developnent of such disturbance analysis systems will, of themselves, provide considerable insight into reactor behavior which will be useful in design and in operator training.
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2.
COMMENTS ON Fi 1980 SUPPLEMENTAL REQUEST R)R TMI-RELATED RESENICH 2.1 Prcposed Request _
Much of the NRC Reactor Safety Research Program will be redirected toward TMI-related problems in Fl 1980.
A portion of this will be funded by reallocations within the RES budget, but a total of $29.8 million has been requested to fund the remainder.
The amounts requested are listed by programs in Table 2.1, together with the changes proposed by the BRG.
The original request f rom REF was for $29.8 mi;.' ion.
This was taodified by the BIC as follows:
Delete $1.6 million for items 1.d, e, f, with the proposed research being funded through internal reprogramming.
Delete $0.4 million for item 3.b; no reason given.
Add $3.0 million to item 8 for FI 1980 and delete a cor-responding amount f rom Fl 1981 to provide for a more orderly growth of the program.
Delete $0.2 million for item 9.a with the proposed re-search being absorbed in the base program.
Delete $3.4 million for item 11 and set aside for Commis-sion consideration and decision on NRC policy direction.
2.2 General Recommendations The ACRS supports a significant redirection of portions of the safu/
research program in FI 1980 to deal with questions raised by the acci-dent at TMI.
Because of the size of the program required, and since ar attempt to fund all of thir research by reprogramming Fi 1980 funds would disrupt seriously the continuity and progress of important ongoing programs, the ACRS agrees that supplemental funding is needed for FY 1980.
The ACRS believes that the proposed level of supplemental funding for FY 1980, at about $30 to $31 million, is appropriate to the extent of the overall program and the portion to be funded by reprogramming.
It is noted that $3 millior, additional is proposed for research on Waste Management, not specifically for IMI-related research, but to provide bf
2-2 more orderly growth of tnis prcryram durira FY 1980 and 1981.
The ACRS finds this acceptable.
The ACRS recommends strongly that the $3.3 miltion for research on Improved Reactor Safety be restored to this request.
This is commented on further below.
Although the ACRS agrees that additional furJs are needed for FY 1980, and that the amount proposed is appropriate, in some cases it does not necessarily agree with the specific programs proposed or with the alloca-tion of funds among them. " nose programs for wt11ch the ACRS believes the content, emphasis, or di ection should be changed are given in the following section.
In making these comments, the ACRS realizes that in many cases the programs have not yet been defined in detail and that changes may be forthcoming in response to its coments.
2.3 Specific Commen*1 The following comments are referenced to the items in Table 2.1.
1.a.
S_ystems Engineering - l'pgrade Semiscale for PWR Transients The ACRS has reservations concerning the proposed up3rade of Semiscale to study PWR transients.
The trail scale of the facility makrs the extrapolation of obser ca';ons to full scale very dif ficult, and the NRC Staff has not had time to sitJy in detail the usefulness of experiments f rom the proposed upg radeo facility.
The Committee is not able to endorse this program at this time.
1.f.
Systems Engineering
'INI Postnortem The ACRS supports the general idea of NRC participation in a 'INI pcst-mortem of safety-related equipr.ent and questions of requalification.
However, it is not clear to the Committee that the timing of such work will be soon enough to justify the proposed level of expenditure.
3.a.
Code Developnent - Modifications and Checking of Existing Codes to Handle Transients The ACRS wishes to emphasize the importance of using available codes to study small LOCAs and anomalous transients.
3.b.
Code Development - Establish Data Bank for Each Operating Reactor.
The ACRS believes that establishment of the prcposed data bank fcr each operating reactor cculd be deferred in relation to other higher priority matters.
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2-3 4.a.
Fuel Behavior - Coolability of Damaged Cores The support of the proposed augmentation of the PBF program to examine phenomena related to degraded cooling and damaged cores is in the context of the general recommendation by the ACRS that the PBF program emphasize experiments related to core damage and to small and large scale fuel melting in the coming years.
11.
Improved Reactor Safety The ACRS recommends strongly that this item be restored. The original Fi 1980 budgc' request for $4.3 nillion was barely sufficie:1t to begin work on the inicial program proposed in NUREG-0438 at the request of the Cong ress. Tne budget for this item was reduced to $1 million by the CMB, and its final disposition by the Congress is still uncertain.
The supplemental request of $3.4 million will restore this item to its original level. Since all of the research originally proposed for this program as well as that now proposed for the revised program can be related to the B1I accident, the ACRS considers it essential that the NRC increase significantly the pace of this program.
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2-4 TABLE 2.1 PROPOSEC FY SO SUPPLEMENTAL REQUEST Budget in Millions 1.
SYSTEMS ENGINEERING RES BRG a.
Upgrade semiscale for PWR transients
$3.0
$3.0 b.
Upgrade TLTA for BNR transients 2.2 2.2 c.
Separate effects and thermal hydraulics 1.3 1.3 tests y) d.
Instrumentation needs developed 0.2 0
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e.
Response of plant equipment to accidents 0.5 0
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f.
TMI postmortem of safety related equipment 0.9 0
and requalifications
$8.1
$6.5 2.
LOPr a.
Modify LOFT to accelerate small LOCAs
$1.0
$1.0 b.
Install improved control room display and
_1_. 0
_ _1. 0 diagnostic system
$2.0
$2.0 3.
CODE DEVELOPMENT bbdifications and checking of existing S3.1
$3.1 a.
codes to handle transients (2) b.
Establish data bank for each operating
_0.4 0
reactor
$3.5
$3.1 4.
FUEL BEHAVIOR a.
Coolability of damaged cores
$2.4
$2.4 b.
Maintaining containment integrity under 0.5 0.5 fuel melt conditions c.
Examination of TMI fuel (planning and 1.0 1.0 transportation) d.
Fission product chemistry and plateout 0.6 0.6 e.
Improved understanding of coolant chemistry 0.5 0.5 f.
Hydrogen behavior in coolant and containment 0.6 0.6
$5.6
$5.6 5.
PRIMARY SYSTEM INTEERITY a.
Hydrogen embrittlement
$0.4
$C.4 Thermal shock of vessel fdF hj_ gh p,{estpre b.
0.6 0.6 3
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$1.0
$1.0
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2-5 TABLE 2.1 (Cont'd)
Budget in Millions 6.
SEISMIC ENGINEERING SAFETY RES_
BRG a.
Containment failure modes
$0.2
$0.2 b.
Response of plant equipnent and struc-1.0 1.0 tures to accident conditions c.
Benchmark testing of structural and
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0.3 0.8 piping system analysis codes
$2.0
$2.0 7.
REACTOR ENVIRONMENTAL EFFECTS a.
Emergency planning and response requirements including data generation and transmission relating to off-site environmental conditions
$0.7 30.7 8.
WASTE MIN GEMENT
$0
$3.0(3) 9.
SAFEGUARDS Ef fects of emergency ccnditions of safeguards a.
I4) effectiveness
$0.2 O
10.
RISK ASSESSMENT a.
Risk implications of decontamination
$0.2
$0.2 alternatives b.
Develop event-trees of accidents leading 1.4 1.4 to core damage c.
Analysis of human error rates and impacts 1.2 1.2 of human errors i.n risk d.
Operational failure data analysis 0.5 0.5
$3.3
$3.3 11.
IMPRGVED REACIDR SAFETY a.
Develop improved control room display and
$0.8
$0 diagnostics b.
Develop improved status monitoring 0.8 0
c.
Define data transmission requirements 0.1 0
d.
Improved containment concepts 0.5 0
e.
Improved safety systems 1.0 0
f.
Improved value/ impact methodology 0.2 0
$3.4 0(5)
TOTAL RES SUPPLEMENT
$29.8
[. I 7 17j BRG RECOMMENDATIONS
$27.2 + $3.4
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set aside
= _ _ _ _ _ _. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _..
2-6 TABLE 2.1 (Cont'd)
NOTES:
(1)
BHG agreed in the need for the indicated efforts but recommended a budget level of $6.5 million.
This allowance was stated to be for the higher priority items and the three programs marked should be funded through internal reprogramming.
(2)
BDG deleted these funds.
(3)
B% concluded that for an orderly growth of waste management pro-grams $3.0 million scheduled for FI-81 should be transferred to FY-80.
(4)
BRG deleted these funds and recommended that this study be absorbed in the base program of $5.0 million.
(5)
BRG set aside these funds for Commission decision.
The BRG com-mented that this was done "in view of the Adminstration's position on Improved Reactor Safety during the FI 80 budget reviews and Congressional action to date on the PI 80 program...."
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3.
COMMENTS ON FY 1981 BUEGET 3.1 Introduction The following sections contain the recommendations of the ACRS regarding the funding levels and programs in each of the major areas cf reactor safety research.
The figures referenced are those requested by RES and those resulting from the BRG mark-up as of July 10, 1979.
These items are )isted in Table 3.1.
3.2 LOCA-ECCS This section includes items from the following program areas:
Systems Engineering LOPr Code Developaent The proposed budget has many items of heavy financial commitment of a long-range nature.
Such budgetary commitments are sometimes necessary but may also contribute to the continuation of significant gaps in the program.
The Committee would view favorably some reallocation of funds from the budget request for a few of the specific items covered in this section to the study of topics indicated in the first chapter of this report.
The budget requests for LOCA-ECCS are listed in Table 3.1 together with changes proposed by the BRG.
Comments on specific items follow.
3.2.1 Systems Engineering a.
The budget for Semiscale includes some "upg rade" in the facility and some corresponding extensions in the test series.
The ACRS recog-nizes the technical limitations of this facility and believes that it is undesirable to view it as an " integral" facility.
It believes, further, that some reduction in the budget for this item could be made to make funds available for other studies already described in this report.
b.
The ACRS supports this budget for Blowdown and 'caficod Heat Transfer.
c.
The budget request for NRC participation in tne international 3-D Flow Distribution studies is $12 million and has been reduced by the BFC to $10 million with $2 million set aside.
The ACRS has no comment on this action.
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3-2 d.
The ACRS recommends that the funds requested for ECC Bms_s_Research be reallocated to other research projects having higher priority.
e.
The proposal tar Model Development Experiments has an expanded budget which includes some containment intercompartment flow tests which could contribute to improved code description of containment.
The objectives of the program are reasanable and should be approved.
- f. & g.
These items are Operational Safety and Technical Support, The ACRS notes that the BRG has set aside totally the request for Operational Safety and has reduced the budget for Technical Support.
The ACRS believes that the increase in the budget request is, in part, a conse-quence of ACRS recommendations in its 1978 Report to Congress.
In particular, those recommendations related to human factors (man-machine interface, appliceble to both operator action and maintenance action),
computer controls, and operational safety studies (evaluation of opera-tional experience and incidents).
The ACRS recommends that the funds requested for these programs be provided.
The programs on fire protection, qualification testing, and noise diag-nostics are well along and should be completed, but some attenuation and elimination can be tolerated here if other priorities so require.
3.2.2 LO?r The budget request for LOPT is $49.3 million and the BRG recommended
$48.0 million by reducing the Facility Sugport item from $11.3 to $10.0 million.
The ACRS supports the request for $49.3 million since it believes that the test prog rams in the facility would thereby be accel-erated.
3.2.3 Code Development The request for this budget item is $15.2 million which has been reduced to $13.2 million by the BRG. The entire reduction was in TRAC Assessment and AJplications which the CRG indicated contained some duplication in TRAC Application funds in RES and NRR.
The ACRS cannot comment on this point except to say that TRAC Assessment and Applications are important activities.
3.2.4 Concluding Remarks It is evident that the LWR safety research on LOCA-ECCS, which has long been concerned with the large break problem, has properly been broadened to consider the complete spectrum of loss of coolant accidents.
The ACRS strongly urges a rapid and thorough expansion of safety research to include an extended examination of safety problems,which arise on 6 b 'J II
3-3 the secondary side of PWRs.
Loss of coolant on the primary side can be initiated by failures elsewhere than in the primary system.
The loss of electrical power, for example, eauld produce loss of pumps and valves on both the primary and secondary sideo simultaneously as a consequence of loss of motor and/or control power.
Loss of environmental control for equignent may cause rapid and permanent loss of critical equipnent long before actual core damage occurs.
3.3 Fuel Behavior 3.3.1 Clad and Fuel; Fuel Codes This work is of substantial aid in reaching regulatory decisions, and should continue at current levels.
Work on modeling severe over-heating, as in 'IMI, is encouraged.
3.3.2 In-Pile Testing (PBF)
PBF represents about 60% of the total fuel behavior research budget. The information on fuel behavior during reactivitv insertion accidents (RIA) is still felt by NRR to be inadequate.
If these accidents are of suffi-ciently low risk (low probability and/or low energy insertions), such research is not necessary. NRR should reevaluate the regulatory require--
ments.
If consideration of RIA is unnecessary, then the PBF program should probably be phased out over the next few years unless the reactor can be of appreciable aid in studying flow starvation and fuel meltirt3 accidents.
3.3.3 In-Pile Testing (Other)
These are confirmatory programs related to core behavior following a large LOCA.
The priority is probably low.
The NRU work should be terminated in FY 1983 as planned.
Although the ESSOR program has attractive aspects, it should be reviewed carefully before commitments are made.
3.3.4 Fuel Melt This work currently includes steam explosions and interactions of molten fuel with concrete.
In NUREG-0496 the ACRS recommended that work on phenomena important to the course of postulated core melt accidents should continue to have high priority.
In sections 1.2.4 and 1.2.6 of this report, the ACRS has recommended an augmented research program on steam explosions and a conceptual study to examine the practicality of core retention within containment. The ACRS recommends that the existing program be reoriented and strengthened accordingly.
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3-4 3.4 Primary System Int grity Primary system integrity is concerned with detecting the presence of incipient cracks in the pr mary systen and predicting their growth.
3.4.1 Fracture Mechanics This orgoing program addresses important questions.
It should continue as planned.
3.4.2 Operating Effects This prcgram consists of two areas, Irradiation Ef fects and Dosimetry, a valuable well organized program, and Steam Generators, about which the ACRS has reservations.
The main theme of this latter program involves a detailed, destructive examination of one of the Sorry steam generators at PNL.
The work should be limited to the correlation between NDE indications and tube integrity until a careful study has indicated the positive contribution to be made by additional work.
3.4.3 Non-Destructive Examination This is an expanding program on an important topic.
The coherence, as well as coordination, with regulatory needs, leaves something to be desired. The program should be funded, but the ACRS urges that the NRR and RES managements improve the coordination of the program on Primary Vessel Integrity and regulatory needs.
3.4.4 Corrosion and Cracking The recurrent problems of pipe cracking in BhRs and NRs are disquiet-ing.
The new program on cracking in BWR piping should be encouraged and should be broadened to consider the corrosion accelerated crackey3 being found in PWR systems.
The question of water chemistry limit >
required to approach more trouble-free operating conditions should also be addressed.
3.5 Seismic Engineering Safety The requested budget proposes growth from $8.4 million in FY 17.9 to
$19.9 million in FY 1981.
The major growth is proposed in the areas of structural and mechanical engineering.
The BRG has proposed a funding level of $13.9 million in FY 1981.
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3-5 3.5.1 Structural Engineering With regard to the Seismic Safety Margins Research Program (SSMRP),
the ACRS agrees, in principle, to the proposed growth in funding.
However, the ACRS wishes to defer detailed comment at this time.
The ACRS agrees that a program which would lead to the benchmarkiry of structural codes and to the development of an inhouse analytical capability for spot audit calculations by the Staff has merit.
'Ihe ACRS recommends that such a benchmark program be designed to use many of the existiry experiments to test the vendor codes and that an experi-mental program not be developed as part of this ef fort.
The benchmark problems should be designed so that input parameters are exercised over the full rarge, and resulting sensitivities and validity limits can be identified.
The ACRS agrees that a program on water ha uner is needed.
The planning of such a program should be interdisciplinary, involving personnel expert in mechanical components, thermal hydraulics, accident analysis and probabilistic and system considerations.
The ACRS supports the program on load combinations, and recommends that the work be planned in cooperation with the Probabilistic Analysis Staff.
With regard to containment studies, the ACRS wishes to support work on the buckling failure modes.
The experimental program should be designed to yield information directly relevant to such failure.
The ACRS wishes to see a better defined program before of fering a recommendation on the containment safety margins program.
The ACRS supports the proposed work on engineering characterization of seismic input motion and on flood hazards and flooding effects.
Other proposed projects deserving attention, but at a lower priority, include the following:
Adequacy of codes and standards - concrete Safety margins for structures other than containments Dynamic testing Damage assessment of structures Ductility under impactive loads bE
3-6 3.5.2 Mechanical Engineering The ACRS supports the SSMRP program and the work on load combinations.
The latter program should be planned jointly with the Probabilistic Analysis Staff.
The ACRS supports an analytical program on the benchmarking of piping codes and the proposed ASME code assessment effort.
The remarks made with respect to the benchmarking of structural codes apply also here.
With some reservations, the ACRS supports the proposed program on purap and valve operability, with a caution that considerable care will be required to limit the costs and yet make the results of generic value.
The ACRS agrees that some means of ascertaining the degree and signifi-cance of damage after a serious earthquake is important for the long-term and supports minor participation in the HER program in the FRG while an appropriate U.S. program is developed.
The ACRS also supports a program on the seismic qualification of mechani-cal and electrical equipent.
Other proposed projects deserving attention, but at a lower priority, include the following:
Snubbers (with no experimental program)
HDR mechanical component analysis and testing HDR monitoring and test evaluation 3.5.3 Site Safety The ACRS supports the research programs on seismicity and tectonics.
The Committee notes the absence of research programs on hydrology as it might reflect on site suitability, particularly in the event of a serious accident involving core melt.
The ACRS recommends that within either the seismicity program or under the SSMRP, priority should be given to provision of an estimation of the recurrence interval for earthquakes of successively greater intensities, together with an evaluation of the uncertainties in such estimates for present or projected reactor sites, as well as on some suitable regional basis.
The recurrence intervals examined should extend as far as a mil-lion or ten million years.
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3-7 The ACRS is not prepared at this time to endorse the large proposed growth in the program on atmospheric transport and diffusion of radio-active materials.
3.5.4 Summary The ACRS recommends a funding level of about $17 million for FY 1983.
The Committee also suggests that further attention be given to the reliability of electrical systems and components under earthquake conditions.
3.6 Fast Breeder Reactors and Advanced Converters This section relates to Items 7 and 8 in Table 3.1.
The tentative budget for FY 1980 shows an allocation of 313.7 million for Fast Breeder Research.
There is some indication that an additional $3.7 million may be allocated by Congress, specifically for research related to Gas Cooled Reactors.
RES has requested $22.1 million for Fast Breeder Research in FY 1981 and $3.9 million for Advanced Converters.
The BRG has set aside for Commission decision all of the requested funds in this category. In its 1978 Report to Congress the ACRS commented:
"Unless the U4FBR and other advanced reactor develognent pro-grams are to be deferred for an extended period of time, the ACRS recommends that the Congress continue to regard advanced reactor safety research as a high national priority because of the time required to resolve important safety questions.
Many of the current safety problems associated with light-water reactors have resulted f rcxn the fact that safety re-search lagged behind reactor development.
If an advanced reactor prcgram is to be pursued in the U.S., related safety research should be carried out concurrently with develop-ment. 'Ihis will permit licensing to proceed in an orderly fashion when specific projects for advanced reactors are submitted."
The ACRS reiterates its conviction that an Advanced keactor Research program should be carried on.
RES states that the $22.1 million represents a 25 percent increase over the original 1980 requests of about $16 million, plus escalation, and identified this increase as needed to respond to the recommendations of the ACRS as given in its 1978 report.
Tbe ACRS endorses the level of $22.1 million for Fast Reactors, and 43.9 million for Advanced Converters for FY 1981 as requested by RES.
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3-8 The ACRS har the following comments based on the prcgrams proposed for Fast Breeder Reactors and for Advanced Converters.
3.6.1 Fast Breeder Reactors a.
Analysis This is primarily code developnent and qualification, but includes some work on accident delineation which purports to be responsive to the ACRS recommendation of 1978 that "NRC undertake a comprehensive study of the safety questions that are likely to arise for commercial WFBRs.... The ACRS believes that there is a high-priority need to review all possible sources of serious accidents (e.g.,
loss of shutdewn-heat removal capability), their probabilities, and their level of seriousness in plants of comercial size.
Considerable use of probabilistic analysis techniques shoeld be made.
Preliminary conceptual designs should be utilized in the studies as a means for focusing on an integrated approach to the solution of problems such as post-accident heat removal."
How-ever, the ACRS also commented concerning the SIMMER code.
"... it is doubtful that the code can ever be validated in the sense of precise calculations of such parameters as pressure, temperature, energy release, etc.
Rather, the ACRS believes that the primary value of the code will lead to increased understanding of the event....
The ACRS expects that reduction of the code development goals will lead to more modest experi-mental needs and lower costs than previously anticipated."
The intent was that addditional emphasis be given to investigation of a broad spectrum of accidents.
The ACRS does not believe that the proposed FY 1981 allocation givea enough enphasis to non-CDA related accidents.
Attention is directed again to the recommendation quoted in part abcVe.
It is believed that both accident delineation and accident prevention should receive greater attention than now seems indicated.
In addition, the accident delineation work that is proposed seems to put too much emphasis on the CRBR.
However, the SIMMER code and the other analytical activities are viewed as important and valuable activities, and need to be continued at a level adequate to sustain those activities.
b.
Safety Test Facility Studies These are stated by RES to be in response to the ACRS comment that 'It is recommended that the NRC carry out a study to determine whether new experimental facilities or programs will be needed to demonstrate the va)idity of natural convection cooling on commercial-sized WFBRs for both pool-and loop-type reactors."
It is proposed to reactivate STF studies and use SSC and COMMIX for this purpose.
It is not clear that the necessary determination can be carried out using this approach.
We recommend that RES carry out additional planning of methods to resolve this issue, and review it with the ACRS.
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3-9 c.
Aerosol Release and Transport This is a combination of analyses and experiments aimed at an important problem area.
The work seems well planned and is producing results.
d.
Materials Interaction This item includes funds for loop design and fabrication and for a series of fuel tests.
It is clear that fuel research needs to be done.
While the NRC needs to do work on problems crucial to licensing concerns, more determined ef fort should be made to have the fuel developers assume a larger part of the investigative burden.
In addition, more effort is needed to obtain a more precise formulation of the questions to be asked and how the answers are to be obtained with these facilities.
e.
System Integrity The proposed program involves testing of the CONTAIN code and carrying out a set of experiments associated with core melt retention, core debris coolability, and container cell liner re onse to accident loads.
Some of the work on core melt retent' s also useful in connection with licensing concerns of the RIP.
Th ark associated with this item seems appropriate to future needs in the development and licensing of fast reactors.
However the ACRS believes, as recommended in its 1978 r e po r t, that specific attention should be given to the study of alternate containment systems and to conceptual studies of systens for retaining a molten core in containment.
3.6.2 Gas Cooled Reactors The funds requested would be used primarily to support Fort St. Vrain related questions on structural graphite, the response of the core to seismic loads, and primary system integ r i ty.
The proposed work is needed, especially if eventual developnent of the GCR is anticipated.
The approach being used is somewhat fragmented.
In aeneral, as in last year's report to the Congresc indicated, the ACRS recommends that a broader spectrum of possible fast reactor acci-dents be examined. The Advanced Reactors program proposed for FY 1981 moves very slightly in that direction.
The movement should be accel-erated as soon as feasible.
3.7 Reactor Environmental Effects In a broad sense, this subject area involves three specific subunits:
(a) identification and control of the sources of radiation within 4rc 3n.
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3-10 nuclear power plants and their potentiality for release; (b) the avenues through which released radionuclides can be environmentally transported to population groups, and (c) the health impacts of the resulting ex-posures. The last two items in this list appear to be adequately ad-dressed within the current prcgram; this is not the case pith respect to the first.
In fact, the ACRS was unable to identify a r mearch project specifically directed to this topic. Therefore, the Committee reiterates the recommendations given in its 1978 report, namely, that the NRC develop and implement programs to address the following areas:
(a)
Research to determine the basic factors that govern radionuclide buildup in reactor cooling systems, includirg the possible influence of operating practices such as rapid temperature variations, load-following, end-of-fuel-cycle operation, and variations in coolant chemistry.
(b)
Research to develop improved means for removing radioactive mater-ials from the primary coolant circuit.
Before such systems can be developed, however, there is a need for the acquisition of much better data on the chemical and physical properties of the material deposited, and on the mechanisms of its formation, deposition, and removal.
These data are required to help establish criteria for controlling the amount and character of radioactive material present in the coolant circuit for purposes of meeting the as low as reasonably achievable (AUOM) criter-ion.
In the case of item (a) a research prcgram needs to be developed and funded.
Since EPRI is active in this area, this program should be closely coordinated with that organization.
In the case of item (b),
the program as oo*1ined in the proposed FY 1981 budget is both un-focused and inadec.te; this needs to be corrected.
In addition to the above, the ACRS recommends that efforts to inprove the measurements of neutron exposures in nuclear power plants be contin-ued.
The proposed FY 1981 funding for research on this item, which is covered under item 9.f.,
" Occupational Radiation Exposure," appears adequate.
The ACRS also recommends that greater attention be directed to research on reduction of occupational exposures during repairs, inspection, or replacement of major nuclear power plant components.
Estimates show, for example, that with current practices, occupational exposures associ-ated with the replacement of the steam generators at several U.S.
power plants will be high.
Since the building layout, for example, the size and location of equipnent hatches, can have important effects on the
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3-11 complexity of major maintenance operations, such factors should be analyzed in detail.
Research to confirm imp;oved decontaminating pro-cedures that could be applied prior to the removal of such units might also be beneficial.
The budget allocation for research on these needs (Item 9.h., " Decommissioning") appears reasonable if the work is properly oriented.
Another area that needs to be addressed within this program relates to emergency planning and post-accident recovery.
The Three Mile Island accident revealed a number of deficiencies in our ability to assess and respond to such situations.
Specific needs in this area include:
(a)
Research on steps that might be implemented in the recovery and reentry phase following an accident.
This prog ram should include evaluations of designs and procedures to facilitate the decontamina-tion and recovery of major nuclear power plant systems.
It should also include research on procedures to aid decisions by medical and cther authorities concerning the affected offsite population; methods for decontaminating and reclaiming of fsite land, buildings, and equip-ment; and the establishment of dose limits or guides for population groups desiring to return to areas that have been evacuated.
These tyres of problens do not appear to be adequately covered in the cur-rent budget.
(b)
Research on the developnent of instrumentation, and methods for quick interpretation and estimation of the timing, nature, and quantity of radionuclide releases in the event of a serious accident.
Current budgetary allocations for research on these types of problems (con-tained within i tems 9.a. and e.) appear to be inadequate.
The Commit-tee recommends that they be increased.
To assist in complying with the recommendations given above, the ACRS suggests that certain projects now planned within this budgetary category might be reduced and/or deleted.
Candidates to be considered include several sub-elements listed in " Ecological Processes," " Ecological Impacts" and "Socioeconomics and Regional" (Items 9.b., d., a nd e. ).
Reductions or deletions might also be considered under "Ef fluent Control" (Item 9.g.), particularly those projects directed to further refinements in techniques for assessments of compliance with 10 CFR 50, Appendix I.
The ACRS believes that the BFC recommended overall level of funding at $6.2 million is adequate.
However, we urge that greater efforts be directed to establishing priorities for research in these areas and that care be taken in developing better procedures for the identifica-tion and selection of projects to be funded.
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3-12 3.8 Fuel Cycle and Waste Management These two categories are discussed jointly inasmuch as several of the perceived needs in the Waste Management category are included within the Fuel Cycle budget.
In its review, the ACRS has noted an urgent need for the NRC Staff to define clearly the goals of its waste management program and to establish priorities for the various tasks to be performed.
Compli-cating this situation is the fact that NMSS, which has a projected Pt 1981 budget of $18.1 million and conducts extensive research in this subject area, has been assigned lead responsibility for waste manage-ment activities within NRC.
The proposed FY 1981 RES waste management budget, in contrast, is $12.9 million.
Although the long-term disposal of high-level wastes is a problem, the NRC faces immediate challenges relative to setting criteria for the disposal of low-level wastes, for the management of uranium mill tail-ings, and for the handling of spent fuel from commercial nuclear power plants.
The current research prcgram does not appear to reflect the relative urgency with which each of these problems needs to be addressed.
Attention to research problems associated with the handling, storage and retrieval of spent fuel, for example, appears to be inadequate.
In addition, the lack of clearly defined goals and specification as to how each research project fits into the overall program plan have resulted in a plethora of ongoing projects which ar' difficult to review and manage.
The need for better coordination and direction is obvious.
A portion of these problems appears to be due to a shortage of quali-fied personnel.
This is particularly true with respect to needs in the geological area.
At present, the NRC does not have a sound concept of research needa associated with the determination of geologic and subsur-face conditions that affect the storage of nuclear waste underground.
The proposed Fi 1981 budget, for example, allocates only $200 thousand for research on " Geochemical Processes" associated with high level waste disposal.
Funds for research on "Geotechnical Engineering" also appear minimal, and no funds have been designated for research on " Shaft and Borehole Sealing Technolcgy Evaluation".
It is urged that these portions of the program be examined by competent geologists who are trained and experienced in subsurface investigation, design and construction.
Until such time as full-time staff members qualified in this area can be employed, use of consultants should be explored.
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3-13 Another factor contributing to problems in waste management research is the lack of adequate communication by the NRC Staff with other agencies and organizations active in conducting research or developing policy related to this subject.
These groups include the DOE, USGS, and EPA as well as the NAS-NAE and NCRP.
Even within NRC, there appears to be a lack of adequate interaction and communication among the major program offices.
However, the recently instituted Waste Management Review Group should help to resolve these problems. The importance of such communica-tion is illustrated by the fact that the current DOE radioactive waste budget is approaching $1 billion per year.
To the maximum possible extent, the NRC should keep abreast of the work being done by these other agencies and use every possible avenue to ensure that their work yields results of maximum benefit to NRC needs.
3.8.1 Specific Research and Technical Needs Comments on specific areas are given below.
Criteria for Waste Disposal one of the major roles that NRC will play in the management of radio-active wastes will be to develop criteria for their safe disposal.
Although additional data are needed, the ACRS urges that the NRC begin now to develop such criteria.
Even a cursory effort in this regard muld help identify needed program elements and would assist in es-tablishing priorities for research on topics such as site selection and monitcring, the ef fects of radionuclide migration, and requirements for waste disposal operations associated with decontamination and decom-missioning.
This 5 mld, in turn, provide guidance as to how each program element assiscs in meeting the overall need.
'Ihe developnent of such criteria muld also serve as a guide for determining when ade-quate research had been completed and engineering design could begin.
Increased Attention to Low-Level Wastes Data presented to the ACRS indicate that over 90% of the total volume of radioactive wastes being generated today are in the low-level cate-gory.
Although these contain less than 1% of the total radioactivity to be handled, the volume of such wastes for calendar year 1977 was about 2.5 million cubic feet.
Indications are that the handling of such wastes at the burial sites is largely done by hand (with associated high per-sonnel doses).
Becauce the waste containers are randomly placed in the trenches, space utilization is poor, voids exist, and retrievability would be difficult.
Because of poor plannirg and management, several existing low-level waste disposal sites have had to be shut down and will represent continuing problems for years to come.
Because of the lack of 655 i1n.
3-14 criteria for disposal of such wastes, commercial companies are continuing current operations and planning for the futura without clear guidance on proper procedures. The ACRS urges that the NRC address these problems as promptly as possible and provide the industry with the guidance it needs.
To the extent that research is needed to solve certain aspects of these problems, it should be given top priority.
These efforts should include increased research on methods, such as incineration and acid digestion, that can be used for reducing the volumes of the wastes to be handled, taking into account the active DOS programs in this area.
Proposed FY 1981 allocations in this area (Item 10.b.) appear inadequate.
In addi-tion, no funds have been included in the proposed budget allocation for research on seeking " Alternatives to Shallow Land Burial".
'Ihis is an important area that should be addressed in a meaningful way.
- Lastly, funds for research on the decommissioning and long-term care of low level waste burial sites (Item ll.b. ) appear to be totally inadequate (only one of four designated research project areas is to be funded and then only at a level of $100 thousand.)
Ground Water Hydrology Research on both high level and low level waste management includes items directed to ground water hydrology.
The ACRS recommends that these ef forts be closely coordinated with related studies on core melt accidents so as to assure maximum interchange of information.
Methods for Assaying Wastes One area not apparently addressed by the current research program is the need for the developnent of equignent for assaying the radio-nuclide content of waste packages as received at waste disposal sites.
Such equipnent is necessary for determining whether wastes as received are within the overall radionuclide limits and whether they contain acceptable concentrations of the transuranics. No funds are allocated to these needs in the proposed FY 1981 budget.
The Committee recommends that this situation be corrected.
Management of Gaseous Wastes - Fuel Cycle NRC research on waste management is directed almost exclusively to the handling and disposal of liquid and solid wastes.
The Committee recommends that attention also be directed to research needs for the removal, confinement, and long-tenn storage of gaseous wastes.
The experience at 'IMI, for example, showed that problems were encountered in the holdup systen for gaseous waste releases.
The proposed FY 1981 budget allocates $150 thousand for research in this area (Item 10.a.).
To the extent practicable, these problems should be more adequately addressed.
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3-15 Emergency Planning The proposed FY 1981 budget includes an item (10.c.) directed to research on "Decorporation Techniques for Radionuclides".
The objective of this effort would be to evaluate methods for effecting the removal of radio-nuclides deposited internally.
Unfortunately, this effort is not at present scheduled to be funded.
The ACRS recommends that funds be provided for research in this area and that it be directed primarily to counter-measure actions in nuclear accidents.
3.9 Safeguards The proposed budget for research on safeguards and security in FY 1981 is $4.9 million, which is about the same as the amounts for FY 1980 and FY 1979.
In each of these areas (safeguards and physical security), major and increasing expenditures will be devoted to the developnent of criteria and procedures for assessing compliance with the new and more exacting rules being put in effect (10 CFR 73.55, already promulgated, and 73.45 and 73.46, in preparation).
The major additional items relating to safeguards are directed at the establishment and exercise of a system for material control and accounting; though supporting (non-research) funds are still needed for the developnent of measurenent standards for the great variety of materials containing SNM which require accurate accounting.
The major additional items relating to physical security are directed at the assessment of ef fectiveness of security provisions (alarm, and access control systens; selection, training and performance of guard forces; etc.), and the analysis of vital areas requiring maximum protection, along with studies of possible plant design options which might provide improved protection for vital areas.
The particular programs just mentioned constitute a reasonable and desirable continuation of work initiated during the past few years.
The funds required for these studies are expected to decrease, and the work now seems to be needed in these areas is expected to be completed by or about FY 1983.
Some useful results have already been obtained f rom work on these problems; the need for and the form of the new upgraded rules have been influenced by these studies; some new per-ceptions of sensitivities have been uncovered; and some of the models for assessing ef fectiveness of physical protection systens have beea used by the Staff and by applicants.
There is also an evident need for the guidance documents to provide criteria, methods and procedures to assist licensees in complying with the new, more stringent rules.
(As an indication of this, the number of items of noncompliance reported as a result of physical security inspections of power plants increased between CY 1977 and 1978 by a distinctly larger factor than did the number of inspections.)
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3-16 The programs already referred to would appear to be among the most important current objectives for safeguard research; and would warrant a higher priority than, for example, a project to assess the impact of an event such as the 'IMI accident upon safeguards perfo rmance, from which the most probable outcome would be the preparation in retrospect for a repetition of that event.
A really low present priority could properly be assigned to a project to evaluate the safeguards issues associated with laser isotope separation, important as that may become when laser separation should reach the stage of a practically feasible technology.
This situation does not, of course, apply to centrifuge separation, since a large number of these are running ef fectively, and have been for some time.
Considering the time that may be required to solve some of the main problems posed in the safeguards and other fields, the ACRS would judge that the funding level for safeguards research is reasonable.
3.10 Risk Assessment The requested budget for Risk Assessment is $12.6 million for W 1981; the BRG reduced this to $7.3 million.
The ACRS has previously urged an increasing level of research effort in probabilistic analysis. The ACRS strongly supports the requested funding level of $12.6 million.
The ACRS has several comments related to specific tasks delineated for work under Risk Assessment.
(a)
The proposed studies on Class 3-8 accidents appear to be of rela-tively low priority and their discontinuance should be considered.
(b)
A concentrated effort should be made to develop possible quantita-tive risk acceptance criteria for proposed NRC use.
(c)
The nuclear fuel cycle risk program might be maintained at an equivalent W 1979 dollar level, to help fund other activities of higher priority, some of which are identified in Part 1 of this report.
(d)
The studies on risk from flood should be focused to provide at least preliminary input into the licensing process before FY 1981.
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3-17 (e)
The work on human error rate analysis should be organized so as to provide as much input as practical into the provision of guidelines for improved human performance and operating procedures.
The probabil-istic methodology should be used to evaluate operating procedures for possible misinterpretation and other sources of human error in order to help reduce the probability of degradation of a transient into an acci-dent.
(f)
The developnent of computer-assisted operator guidance to help reduce the chance of human error due to the complexity of a transient or the existence of false er contradictory signals will require an inter-disciplinary approach in which probabilistic methodology will play an important role.
Appropriate steps should be initiated by the Proba-bilistic Analysis Staff (PAS) soon, and if necessary, funding should be reallocated within PAS to begin work on the relevant methodology.
(g)
The developnent and application of probabilistic methodology within the NRC Staff has been slowed by the lack of knowledgeable personnel.
PAS has run a one-week intensive course.
However, a course of this duration appears to be too short to provide the training and appreciation needed for the application of these methods.
It is recommended that a longer (four to six week) course be developed, possibly in conjunction with some university, which would enable provision of a greater capa-bility within the NRC Staf f with regard to the application of proba-bilistic methodology.
(h)
The PAS Program includes some plans to look at time-dependent fail-ure rates.
However, it is not clear whether there are plans to study the possible implications to safety of the potential for system degrada-tion.
Time-dependent failure rates should be developed for various significant systen components and the possible effects on safety esti-mated for their possible impact on inspection requirements and other licensing considerations.
(i)
With regard to er..ergency preparedness, the ACRS recommends that a short research program be implemented soon to develop means, as practi-cal, of ascertaining the time, rate, type, and amount of radioactivity that might escape from containment into the atmosphere during postulated accidents.
The ACRS has the following general comments concerning the Risk Assessment program:
(a)
The ACRS believes that rather than risk assessment, per se, this
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3-18 group should be pursuing primarily the developent and application of probabilistic methodola3y for use in improving the safety of reactors and to assist in the licensing process.
Risk assessment wuld remain an activity but one having a lower priority.
(b) The PAS has provided recommendations to NRR concerning the potential for risk reduction arising from generic issues and other licensing issues.
The same approach should be applied to a review of the NRC safety research program in order to help assess whether the current levels of funding are in rough balance with the risk reduction potential and other factors of potential importance in judging the priority to be given various research tasks and programs.
(c)
There is a need for closer interaction between the PAS and the NRC Staff in the of fices of Nuclear Reactor Regulation, Inspection and Enfo rcement, and Standards Developent.
Need exists for close interac-tion between PAS and an NRR group that includes experts in the several kinds of systems (electrical, mechanical, air, thermal-hydraulic, con-trol, etc.) important to reactor safety, so that a continus.ng and current assessment can be made of the safety implications of potential design changes or of operating experiences in a manner that includes interactive aspects and reliability and risk aspects.
(d)
Several of the general recommendations made ir. ? art 1 will involve ef forts by PAS beyond those delineated in their proposed work scope for FY 1981.
These include:
1.2.3, Accident Studies; 1.2.4, Molten Core Retention; 1.2.7, Siting; 1.2.9, Traasient Simulation in Research and Licensing; 1.2.11, Application of Probabilistic Methodology; and 1.2.13, Disturbance Analysis.
The ACES recommendation of a funding level of $12.6 million in W 1981 is made in recognition that these efforts will require additional resources.
3.11 Improved Reactor Safety In 1977, the Congress directed the NRC to prepare a long-range plan for research to improve reactor safety.
This plan was developed and pre-sented to the Congress in April 1978 (NUREI;-0438).
In late FY 1979, work was begun on this program, at a very low level, using reprogrammed unobligated FY 1978 funds and some obtained by reallocations within the RES budget.
The FY 1980 budget request for $4.3 million was reduced by the OMB to $1.0 millica.
Congress has not yet approved an appropriation i[U g w ].
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3-19 for FY 1980, but an additional $3.4 million has been included in the NRC's supplemental request for FY 1980.
The ACRS support for this increase has been indicated in Part 2 of this report.
The budget request of $6.6 million for FY 1981 has been set aside for Commission decision by the BRG in view of the uncertainties in direc-tion provided by OMB and the Congress in view of their actions on the FY 1980 budget requests.
The ACRS has indicated repeatedly its strong support fo r a vigorous and well-funded program of research to improve reactor safety, in its report to the Commission on NURE-0438 and in its reports to Congress in 1977 and 1978. It con".inues to support this program and urges strongly that the full amount requested be restored to the FY 1981 budget.
Although the ACRS supports the level of fundli., oroposed for FY 1981, it does not agree with the currently proposed allocation of funds among the various program areas originally listed in NURE-0438.
Specially, the ACRS recommends the following changes in scope and emphasis, within the proposed budget level:
(a) Alternate Containment Concepts.
This program should be augmented in both FY 1980 and 1981, with the objective of examining all types of containments in greater depth.
(b) Alternate Decay Heat Removal Concepts.
This program should be augmented in both FY 1980 and 1981, in directions leading to conceptual design studies for both PWR and BWR systems.
The goal by the end of FY 1981 or 1982 should be completion of studies leading to two or more possible design approaches for each type of reactor systen.
(c)
Alternate ECCS Concepts.
The proposed funding for this program is considered adequate at the levels requested for FY 1981.
(d)
Human Interaction.
The proposed funding for this program is considered adequate at the levels requested for FY 1981.
(e)
Advanced Seismic Design.
The ACRS believes that work in this area might well be deferred until af ter FY 1981 in order to permit the augmentations in other areas recom-mended above.
Such deferral will also permit the new data, knowledge,
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3-20 and insights that are expected to be obtained from the Seismic Safety Margins Research Program to be used in the planning and execution of research on advanced seismic designs.
(f) Scoping Studies of Other Possible Improvements.
%is program should be augmented in FY 1981, in order to provide timely guidance for further work in subsequent years.
In view of the TMI accident, a promising area deserving of early study is core retention measures and their potential for mitigating the release of radioactivity through the liquid pathway.
(g)
Improved Value-Impact Methodology.
The ACRS believes that the developnent and use of this methodology is important but that its application is not limited to the evaluation of proposed concepts or systems to improve reactor sa fety.
It can and should be used to evaluate the values and impacts of such new criteria as those re;ating to pipe breaks inside and outside containment, fire protection, a nd A'IMS, and to determining the extent to which these improvements in safety should be applied to new plants, plants under construction, and plants already in operation.
W is methodology can be used also in determining the potential value of research programs con-sidered to be chiefly confirmatory in nature.
At the same time, the ACRS believes that this methodology has only marginal value for the selection of new topics relating to improved reactor safety.
The pro-cedures followed in arriving at the five areas listed in NURDG-0438 were considered by the ACRS to be quite adegn-3te at the time.
This judgment has been confirmed by the fact that all the proposed TMI-related research to improve reactor safety falls well within the scope of the principal areas identified in NUREII-0438. For these reasons, the ACRS believes that, although research on improved value-impact methodology is desirable and should be.;onducted, the funds for this research should not be taken from the relatively small sums requested for research to improve reactor safety.
655 10.
3-21 TABLE 3.1 FY 81 BUIX;ET BUDGET (In millions)
SYSTEMS ENGINEERING a.
Semiscale
$ 8.1
$ 8.1 b.
Blowdown & Reflood Heat Transfer 8.4 8.4 II) c.
3-D Flow Distribution 12.0 10.0/2.0 d.
ECC Bypass Research 0.9 0.9 e.
Model Development Experiments 3.5 3.5 f.
Operational Safety 9.8 0.0/9.8(2) g.
Technical Support 2.6 1.9
$45.3
$32.8 II)BRG set aside for NRC consideration due to change in scope of the effort and also because $1 million is for contingencies not included in NRC directed ceiling of $59 million for this program.
(2)BRG set aside for NRC consideration because this funding is generally for new ef forts proposed oy RES and out-year impacts reflect significant growth.
BUDGET (In millions)
LDFT a.
Program Planning and Analysis
$ 5.0
$ 5.0 b.
Fuel 8.3 8.3 c.
Operations 8.9 8.9 d.
Instrumentation 9.0 9.0 e.
Facility Support 11.3 10.0(3) f.
Engineering and Physics 6.5 6.5 g.
Advanced Fuel Instrumentation 0.3 0.3
$49.3
$,8.0 (3)BRG said that accuracy and timing of scheduling and testing not precise or exact enough that full request is required by FY 81.
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3-22 TABLE 3.1 (Cone)
BUDGET (In millions)
REE BRG 3.
CODE DEVELOPMEt!T a.
Systems Codes S 6.3
$ 6.3 b.
Component Codes 1.6 1.6 I4) c.
TRAC Assessment and Applications 7.3 5.3
$15.2
$13.2 (4)BRG said that RES has not adequately demonstrated that $2.0 million TRAC application is not duplicative with the NRR program.
BUDGET (In millions)
FUEL BEHAVIOR a.
Clad and Fuel
$ 2.6
$ 2.6 b.
Fuel Codes 1.5 1.5 c.
In-Pile Testing (PBF) 16.1 16.1 d.
In-Pile Testing (Other) 4.2 4.2 e.
Fuel Melt 4.1 3.5(5) 328.5 557 5 (5)BRG deleted low priority fuel melt effort for FNP.
BUDGET (In millions)
PRIMARY SYSTEM INTEGRITY a.
Fracture Mechanics S 5.9
$ 5.9 b.
Operating Effects 6.3 6.3 c.
Nondestructive examination 2.9 2.9
$15.1
$15.1 655 i?4
3-23 TABLE 3.1 (Cont)
BUD 3ET (In millions)
SEISMIC EmINEERING SAFETY a.
Structural Engineering
$6.0
$ 3.9 b.
Mechanical Engineering 7.4 3.8 c.
Site Safety 6.5 6.2
$19.9 3T3T9(6)
(6)BRG reduction was based on 1 priority of this research (as assigned by RES). BRG level was.: aid to be suf ficient for RES to pursue a logical progression of effort started with FY 80 supplement.
BUDGET (In millions)
FAST BREEDER REACTOR a.
Analysis
$ 7.8 b.
Safety Test Facility Studies
.7 c.
Aerosol Release and Transport 3.0 d.
Materials Interactions 4.6 e.
Systems Integrity
_ 6.0 7)
$22.1 0.0/22.1
}BRG set aside entire amount for Commission consideration. BRG recom-mended that NRC priorities should be on LWR programs.
BUDGET (In millions)
ADVANCED CONVERTERS I) a.
GCR Program
$ 3.9 0.0/3.9
$ 3.9 30.0/3.9(8)
I0)BRG set aside entire program based on the Administration's decis!vn to terminate domestic program in FY 79.
( t; F)
}05
3-24 TABLE 3.1 (Cont)
BUDGET (In millions)
REACTOR SNIR0tMEffrAL EFFECTS a.
Physical Transport and Effluent
$2.1
$1.3 Characteristics b.
Ecological Processes 0.6 0.4 c.
Radiation Dosimetry and Health 1.2 1.1 Effects d.
Ecological Impacts 1.7 0.3 e.
Socioeconomics and Regional 1.2 0.5 f.
Occupational Radiation Exposure 1.1 0.9 g.
Effluent Control 1.0 0.8 h.
Decommissioning 0.9 0.9 T93 i$6.2I9)
(9)BRG provided minimum level on many areas (except those dealing with probicsn of low level radiation exposure) because of low priority of programs.
BUDGET (In millions)
FUEL CYCLE a.
Effluent Control
$0.7
$0.3 b.
Safety 1.4 1.3 c.
Occupational / Health 1.6 1.2 d.
Environmental Impacts 0.1 0.1 e.
Transportation 1.5 1.5 f.
Decommissioning 0.6 0.6
$5.9
$5.0(10)
(10)BRG reduced funding as some parts of program are not clearly supported by user needs or are supported by outdated requests.
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3-25 TABLE 3.1 (Cont)
BUDGET (In millions)
W\\STE MAtuCEMEm' a.
liigh Level Waste
$ 8.1 b.
Low Level Waste 5.7 c.
Tailings 2.1
.n 5 9 S12.9 (11)BTC fully funded these programs but recommended a shif t of $3.0 million to FY 80 to provide for a more orderly growth of the program.
BUDGET (In millions)
SAFEGUARDS a.
Evaluation Methods
$2.2
$2.t b.
Inspection Methods 0.5 0.5 c.
Alternative Strategies 4.^
2.3 N7
$4.9 (12)
(12)BFC reduced level because program contained ef forts that are not expected to be needed in the near future. 30.4 million set aside on Breeder Safeguards for Commission decision.
BUDGET (In millions)
RISK ASSESSMENT a.
Methodology and Software
$ 2.5
$ 1.8 b.
Reactor Systems Analysis and Li. censing Support 3.6 1.6 c.
Nuclear Fuel Cycle Risk 2.0 1.4 d.
Training Program 0.1 0.1 e.
Reliability and Human Error D2ta Analysis 2.6 2.1 f.
Acceptable Risk Criteria 0.3 0.2 g.
Improvements to Reactor Safety
, p/ /
Study 0.3 0.1 b ', O I
h.
Operational Safety Data Analysis 1.2
$12.6
$ 7.3(13)
(13)BRG said that program appears to be expanding at too rapid a pace for the number of qualified people that are available.
-=
3-26 TABLE 3.1 (Cont)
BUDJET (In millions)
IMPROVED REACTOR SAFETY
~-
a.
Alternate Containment
$0.8 b.
Alternate Decay lieat Removal 0.4 c.
Alternate ECCS Concepts 1.0 d.
Iluman Interaction 2.7 e.
Seismic Design 1.0 f.
Scoping Studies 0.4 g.
Improved Value-Impact Methodology 0_.
(14)BRG set aside entire program in view of the Administration's position on Improved Reactor Safety during FY 80 budget reviews and Congressional action to date on FY 80 program.
iOh
U S. NUCLE A R REGUL ATORY COMMISSION BIBLIOGRAPHIC DATA SHEET NUREG-0603 4 TITLE AN D SUBTIT LE LAdd Volume No. of approproste) 2 g rave pier,n)
Comments on the NRC Safety Research Program Budget 3 HE CIPIE N T'S ACCE SSION NO
- 7. AU T HO H (Si 5 D ATE HEPOHT COYPLE TE D l YE AH M ON TH Advisory Committee on Reactor Safeguards July 1979 9 PE HF OHM lNG OHGANI/ A TION N AYE AND M AILING ADDHE S5 (/ccrude /r Codel D A TE RE POH T ISSUE D l v AH voNTH Advisory Committee on Reactor Safeguards July 1979 US Nuclear Regulatory Commission e a,3. e 3,,,,,
Washington, DC 20555 8 (L eave blan h 1 12 SPONSOHIN G OHG ANil A TION N AME AND M AI LING ADD HE SS //"r /s.7e IP Co+1 10 PHOJE C T T AS A ACH A UNIT NO 11 CON T H AC s NP 13 TYPE OF HE POHT vF st on c o v e nt o u o u ve aarni 15 SUPPLE VE N T A R Y N O TE S 14 /t e au-nen /
16 ABST H ACT (200 w ords or lessl Recommendations of the Advisory Committee on Reactor Safeguards are presented to the Commissioners for their consideration for both FY-80 supplement and FY-81 budget for the NRC safety research program.
Special attention to both short-and long-term implications of the Three Mile Island accident and their significance to research for both the short-and long-term research programs are included.
F 17 AC Y WOR DS AND DOCUME NT AN AL YSIS 17a DE SC hip TOHS fi )
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