ML19320D597
| ML19320D597 | |
| Person / Time | |
|---|---|
| Issue date: | 06/03/1980 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-1737, NUDOCS 8007210588 | |
| Download: ML19320D597 (13) | |
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1 td d i::ai.::J. i MINT lTES OF THE ACRS SUBCOMMITTEE MEETING June 3, 1980 ON CONCRETE AND CONCRETE STRUCTURES April 22 & 23,1980 Washington, D. C.
.s The ACRS Subcommittee on Concrete and Concrete Structures held a meeting on April 22 and 23,1980 in Room 1167, 1717 H St., N.W., Washington, D.C.
The purposes of this meeting were to review the NRC research program, technical assistance programs, and seismic safety margin program (SSMRP) in the area of Structural Engineering. The notice for the meeting appeared in the Federal Register on Monday, April 7, 1980. A copy of the notice is included as Attachment A.
A list of meeting attendees and a meeting schedule are included as Attachments B and C.
No written statements or requests for time to make oral statements were received from members of the public.
INTRODUCTION Dr. Siess, Subcommittee Chainnan, opened the meeting by indicating that it was being conducted in accordance with the Federal Advisory Comittee Act and the Government in the Sunshine Act.
M:'. Elpidio Igne was the Designated Federal Employe,e 'for the meeting.
The structural engineering research programs that are either part of or are in support of the SSMRP will be discussed at this meeting. There will be other w
reviews of the remaining SSMRP programs by the ACRS Subcomittee on Extreme External phenomena.
R_E_ SEARCH PROGRAM - L. Shao, NRC Staff Mr. Shao, Assistant Director of General Reactor Safety Research of the NRC, stated that, in the past, structural engineering research programs provided assistance to NRR and Standards Development.
In the future, however, the l
l Structural Engineering Research. Branch should also address the needs of I&E.
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The new organization of the Office of General Reactor Safety Research and The Structural the.5tructural Engineering Research Branch were presented.
Engineering Research Branch scope of review encompasses the design of plants struebures from the base of the foundation to the point where safety systems,
components and equipment are af.tached.
Seismic analysis of piping systems is performed in the Mechanical Engineering Branch of NRR.
The NRC's role in perfoming audits and performing confimatory research FWR LOCA and inplane-shear in reinforced concrete contain-was discussed.
BWR large ments were cited as examples where the NRC supported all research.
Attendees at the LOCA research, however, is primarily funded by industry.
meeting did not propose that all research be done by industry or the NRC but that some strong justification for government funding be provided for each Criteria should be established in order to determine who shall fund program.
In cases where the NRC is calling for something that may research programs.
be too conservative, government funding of remarch to quantify safety margins should be required. The NRC should be up-to-date on research so that they are able to ask good questions in order to review and assess possible research areas. Program areas mentioned included the shaker table tests in Japan and the core ladle for FNP. Dr. Sidss and Dr. Zudans indicated that AEs do very little in the way of supporting research except in developing their own tools. Mr. Shao added that AEs usually do not want to do research unless it is for big generic problems like those sponsored by owner's groups.
Mr. Shao stated that the Structural Engineering Research Branch programs are classified into three major areas -- engineering definition of loads, pre-The diction of structural response, and criteria for structural perfomance.
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engineering definition of loads includes items like load factors and the so-Structural response includes structure dynamics analysis called effective SSE.
and soil-structure interaction analysis.
Structural perf:r ance includes the
- r capacity of a structure and the margin for that stru:ture in resisting loads.
f These'three programs supply information and tools for evaluation of safety-The major goal of the Branch is evaluai:fon not design.
related structures.
Dr. Siess indicated that one goal of the Seismic Safety Margin Research Pro-gram (SSMRP) is a knowledge of where and how large the uncertainties are in Mr. Shao stated that two major methods are used to determine seismic analysis.
The first approach is safety uncertainty in structural engineering programs.
The second margin (a deterministic evaluation of capacity against design load.)
approach employs methodology using probabilistic-based assessments in the de-termination of structural adequacy.
TECHNICAL ASSISTANCE PROGPAMS Mr. Schauer, NRC Staff, described the technical assistance program (TAP) on the Thisisa2-year ($3bO,000) buckling behavior of steel containment shells.
analytical program to study overturning forces that may cause local buckling of the containment shell due to asynsnetric pressure loads created during LOCA blow-This analytical study will extend buckling into the non-linear range of down.
deformation. One of the products of this particular program will be a computer code that can be used by the NRC to check applicant calculations. This program Dr. Hafiz, NRC will analyze a BWR Mark III and PWR ice-condenser containments.
Staff, indicated that one-and two-dimensional a alyses will be compared in order to better understand buckling load. The effect of penetrations on buckling load, the knock-down factor, and the sensitivity of these parameters will also be It was questioned whether this program should be considered technical studied.
assistance or research.
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Mr. Lipinski, of the NRC Structural Engineering Branch, presented a to develop an.tnalytical model to evaluate resistance and ductility o'f The report, concrete slabs under biaxial-tension, bending, and shear.h of con-writtin by SRI International, has been rejected twice for brtac The contractor failed to develop a simplified model that may be tract.
The analytical model used by the NRC Staff for inderendent evaluations.
The should have been verified by comparisons with actual tests results.
Dr. Zudans and contractor did not report any tests with inplane tension.
Dr. Siess pointed out that tests had been perfomed and that the NRC may have picked the wrong consultant.
Structural engineering case reviews (Byron /Braidwood, Grand Gulf, Sout Con-Texas, Midland) are being perfomed as part of a two-part TAP.
sultants are performing a review to include independent calculations of structural design integrity, seismic inputs, missile resistant barriers Dr. Shewmon wanted to know if the NRC Staff and subcompartment pressure.
would use the consultants again after the consultants had developed ex-Mr. Schauer. indicated that this was a one-
' pertise in this type of review.
time program but could be continued if the Staff did not have sufficient manpower to complete additional reviews.
Tne seismology / seismic design review of Seabrook is a $10,000 TAP co awarded to Dr. N.M. Newmark to expand on his work at Seabrook and to The Kennedy-Newmark criteria for.
comment on intervenor contentions.
piping are being extended into the structures area for the technical assistance program dealing with the evaluation of load and load combi-ll nation problems for BWP Mark II and Mark III containments and drywe The upcom'.ng presentation to the ACRS on soil-structure inter-structures.
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action is planned f-taaa
g a.
A review of nuclear plant structural design (ultimate strength of steel containments) is being perfonned for several ice condenser plants (Sequoyah, McGuire, Cook). Dr. Siess indicated that best estimate (with uncertainties) analhsesforcontainmentcapabilityareneeded. Areas such as penetrations, and as-built containment geometry may be governing and must be considered.
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The post-earthquake irlspection requirement is an effort to put together a systematic plan in order to inspect a plant and make an assessment of f
plant structural integrity following an OBE or SSE. The NRC Staff does not have procedures for post-earttquake inspection at this time. The need for this program and the determination of the level of seismic activity before requiring inspection were mentioned.
The Structural Engineering Branch Te:hnical Assistance Programs in structural areas consit t also of seismic review cf SEP plants by Lawrence Livermore Labora-tory and the seismic consultant services of Dr. Newmark.
Mr. Herring of the Engineering Branch of the Division of Operating Reactors, presented the TAP to evaluate masenry design. This program was initiated be-
'cause of design deficiencies found at Trojan and the use at other plants of The masonry (concrete block) walls to support safety-related piping systems.
contract for the program is administered by Brookhkven Natienal Laboratory and subcontracted to Dr. Goldvil at the University of Maryland. The NRC will issue. criteria on the use of masonry walls currently being used to support safety-related large pipes and other components. Mr. Herring indicated that the La Crosse and Zimmer plants had 315 unreinforced mastnry walls. The NRC wants the nuclear industry to resolve this problem; for example, Trojan is The NRC needs to gain already committed to several long-ter n test programs.
expertise in the area of masonry design.
., Mr. Martore, of the Engineering Branch of the Division of Operating Reactors, presented the TAP on seismic input and analysis techniques. The basic obfoctive is to provide the NRC Staff with assistance in the review of ongoing seismic
- r analysis of design issued on a need basis. The contractor is Lawrence Liver-morehaboratory.
The evaluation of the margin of safety in the seismic design of El Centro steam r
plant was discussed. The El Centro Unit No. 4 (oil fired-80 MWe) experienced 0.5 to 0.6g peak accelerations during the Imperial Valley earthquake of October 1979. The plant experienced minor damage but went back into operation about one hour after the earthquake. Mr. Martore perceives the final result of this program as a table listing various locations in the structure and various pieces of equipment with their calculated accelerations and the actual accele-l rations received during the earthquake.
SEB RESEARCH PROGRAM _
Mr. Bagchi of the NRC Staff present'ed the research programs for the NRC Struc-tural Engineering Research Branch. Each of these programs is described in The total research budget is $2170K for FY80 and $4900K for FY81.
.the handouts.
Mr. Bagchi ind'icated that large penetrations (e.g. the equipment hatch and the personnel access hatch) were expected to be modeled in computer studies of containments but that the details had not been finalized. Dr. Siess suggested j
that the probability of over-pressure in a containment is a lot higher than that of a' major seismic event.
Dr. Pickel indicated that research considering the L
l buckling of steel containments was addressed in many programs.
Mr. Bagchi noted that the buckling of steel containments is contained in the safety margins and performance of Category I structures. Mr. Bagchi indicated that the re-suits of structural tests showed that there is a very large reduction in fundamental frequenev due tn nnn-linear foundation behavior.
. The funding of the flood hazards and flooding effects program ($50K for This program may FY80),4s only for the structural engineering branch.
assess the probability of damage to nuclear plants due to flooding but the pres nt scope of work is to determine probablistic methods of determining The NRC probabalistic analysis staff (PAS) will perform flood levels.
the probability studies while the structural engineering branch will ex-amine the effects of flooding. PAS is being funded separately for this project.
Dr. Siess said that the proposed water hamer research program in structural This engineering did not come under the cognizance of this subcomittee.
program is not funded for FYs 1980 through 1982.
A study to determine the effects of hydrogen explosion and the behavior of containments under internal hydrogen explosion is aeing perfomed by MIT.
The determination of load combinations for the design of structures is a Some of the input for this program will come from the NRC part of the SSMRP.
The expected results of the SSMRP will form a basis for LOCA program.
fomulatiog load combinations and acceptance criteria.
Damage Dyna.ric testing programs for nuclear power plants were discussed.
asse)sment criteria based on changes in frequency spectrum were considered H
as possible criteria for the detemination of i;he amount of damage occurring as a n
result of seismic activity. The size and amount of the cracks in structures can The need for baseline (original) dynamic be correlated for damage assessment.
Dr. Siess testing for specific frequency spectrum analysis was considered.
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felt that dynamic testing to detemine and verify predicted natural frequencies I
for structures was very important. These types of analysis can be used to l
Dr. Siess said that the ACRS has recommended that benchmark computer codes.
benchmark programs for structural codes and the testing of vendor codes be
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>s 8-designed to use many of the existing experiments and that an experimental If existing experiments progra'm not be developed as part of this effort.
It was noted that are.not available, the NRC Staff should inform the ACRS.
the Japanese, HDR, and San Onofre tests could be used to start a code vali-Structural computer code modeling sensitivity and mathe-
<ft-ion program.
matical algorithms require additional study.
Sandia National Laboratories will be examining containment structure safety margins under extreme loads (seismic and LOCA loads). This program is The failure criteria for a primarily concerned with concrete structure.
containment were discussed. Leakage from tte containment but not bursting of the containment was considered the most prominent failure mode.
Dr. Siess requested a detailed breakdown of the budget between safety margins of category I structures program and the buckling program. Mr. Bagchi of the NRC Staff said that he would provide the budget breakdown.
The research program dealing with the effectiveness of QA and inspection pro-cedures will focus on construction proceduras. This program will detennine the effectiveness of the present requirements.
Dr. Siess felt that this pro-gram did not have enough research content to Lelong 'in the research budget.
It could be accomplished as a technical assistance contract on specific items.
1 Dr. Siess cormiented on j
The procurement of research programs was discussed.
his observation that the NRC research staff seemed to be insulated from the detailed cost breakdown of research programs. Mr. Bagchi statad that some SSMRP contracts are sub-contracted out by Lawrence Livermora Laboratory without input from the NRC Staff. The NRC Staff only sees the winning proposal. Direct It access to the actual researchers performing the contract was discussed.
was felt that the process of subcontracting should be influenced by those who have the ultimate responsibility for the project. DOE (in their water reactor
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safety program) has turned over the management of the entire program.to a national laboratory; the responsibility for the results, however, remain
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with DOE.
The jubcomittee considered the degree of control available to supervisory paneis in directing large research programs.
Since money is obligated yearly, a great degree of control is available. Concerns were expressed in redirecking large research programs toward the changing needs of the users.
The redirectico of LOFT toward small scale breaks was presented as an example of the difficulties in redirecting projects.
Funding for SSMRP was discussed.
Studies on the adequacy of codes and standards, computer code benchmarking, and safety margins may be reduced if supple-mental funding for FY80 is not forthcoming.
Dr. Costello, NRC Structural Engineering Research 3 ranch, outlined the current SSMRP projects related to structural engineering. The first project, soil-struc,ture interaction (SSI), will identify sources of uncertainty in state-of-the-art SSI methods and estimate the effects of these uncertainties on plant.
' safety calculations. Task l of the SSI project (a review and critique of present methods) has been completed. The additional tasks (implementation of analytical tools, definition of soil properties, and sensitivity studies) are still in progress.
An interim report on the definition of soil properties will be released soon.
The second project, structural building response, will evaluate state-of-the-art analysis techniques for major structures and develop structural analysis packages for SSMRP calculations. The third project will develop SMACS software and perfom selected'best estimate vs evaluation studies for structural building and subsystem responses.
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NOTES:
(1) For additional details. a complete transcript of the meeting is-available jn the NR; Fablic Document Room,1717 H St., N.W. Washington, D.C. 20555
.,_. or from International Verbatim Reporters, Inc., 499 South Capitol St.,S.W.,
' Suite 107, Washington, D.C. 20002.
(2) Materials provided to the Subcommittee at this meeting are on file in the ACRS Office.
In general, these materials include:
a.
Research Programs and Budgets for the Structural Engineering Research Branch.
b.
SSMRP Projects c.
Technical Assistance Requirements for Seismic Input and Analysis Techniques.
d.
Systematic Evaluation Program (SEP) Tecnnical Assistance Programs in Structural Areas.
e.
Structural Engineering Branch Technical Assistance Progrtms.
f.
Proposed FY 1982 Budget NRC Structural Engineering Research Branch.
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ATTACHMENT A i
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Federal Register / Vcl. 45. No. 68 / Endry. April 7.1980 / N tices 5 ' *-
23554 October 1.1979. (44 FR 56408). oral or (the licensu) which revised the Ucense
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and Technical Specifications for by m:mbers of the Subcommittee.its written statements may be presented by operation of the Nine Mile Point Nuclear consult:nts, and Staff. Persons desiring )members of the public. recordings wi!!
Station. Unit No.1 [the facility) located,
23 make oral statements should notify be permitted only during those portions in Oswego Comty.New York.ne the Dreignated Federal Employee as far of the meeting when a transcript la being amendment is effective as ofits date of in adycace as practicable so that appropriate arrangements can be made kept and questions may be asked only issuance.
to allow the necessary time during the by members of the Subcommittee.its The amendment consists of changes consultants. and Sta!!. Persons desiring The agenda for subject meeting shall to make oral statements should notifv to the Technical Specifications to
=reting for such statemen*s.
i the Designated Federal Employee sv.ar modify the power.to. flow curve and Tussday. AprdC.19ets.!:0:19.nr untilthe 1 appropriate arrangements can be made during plant load changes. In addition.
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in advance as practicable so that allow additional operational flexibility be as fcitows(
to allow the necessary time during the corrections have been made to the conclusion ofbusiness The Subcommitiee may meet in Executive i meeting for such statements.
license to reflect the present power Sessen with any ofIta consultants who may [l The agenda for this meeting shall be limiteions at the end of cycle.
be presint, to explore and exchange their as follows:
Tha vplications for the amendment prehmmery optruons regarding setters which abould be considered dunna the meeting.
Tuesday and Wednesdar. AprilMcndD, complies wih the standards and At the conclusion of the Execuuve Seseion.Jasa Ahnt. unf# W concksion of requirements of the Atomic Energy Act tv Subcommittee wdl hear presentations by i business soch doy
.of1954, as amended (the Act), and the arW hld discussions with representatives of.
& Subcommittee may meet in Executive Comminion's t' des and regulations. The the NRC Staff. the nucient industry, various Session. with any ofits consultants who may '
Commission has made appropriate tulities, and their consultants and other be present, to explore and exchange their Endings as required by the Act and the la addition. it may be necessary for the preliminary opinions regarding matters which Commission's rules and regulations in 10 ht: rested persone.
abou!d be considered dunna the meeting.
CFR Chapter I which are set forth in the Subccmmittee to hold one or more cloud At the conclusion of the Executive Session. license amendment. Prior public notica sessi:na for the purpose of exploring matters the Subcommittee wi!! hear presentations by invoinns propnetary informati:m. I have and hold discussions with represent Wee of of this amendment was not required de.crmined. In accordance with Subsection the NRC Staff. their consultants, and other since de amen 6ent does et win a told)of the Federal Advisory Committee Act l Interested persons.
significant hazards consideration.
(Pub. L 92-463). that, should such sessions be In addinon. It may be.necewary for the The Commission has determined that requireiit is necepary to close these Subcommittee to hold one or more closed the issuance of this amendment will not sessions to protect propnetary information.
senicas for the purpose of explanns =atters See 5 U.1C. 55:(cK4).
involving preprietary tafortsation. I have result in any significant environmental impact and that pursuant to 10 CFR Further information regardin'g toples d
ih e o 13 be discussed. whether the meeting
'Q.Np*d Ai 51.5(d)(4) an snvironmentalimpact has bien canceaed or rescheduled. the (P A.1.sm).that. shodd suu susione bestatement or negative declaration and
,,qmred. it is necewary to close these environmental impact appraisal need Chdtman's ruling on requests for the I
cpportunity to present oral statements sessions to protect proprietary information.
not be prepared in connection with and the time allotted therefor can be See s U.1C. s5:b(cx4).
' issuance of this amendment.
cbtnined by a prepaid telephone call to Further information regarding topics For further details with respect to this th2 cognizant Designated Federal to be discussed.whether the meeting action, see (1) the cpplication for Employee.Mr. Peter Tam (telephone has been cancelled or rescheduled. the amendment dated June 28.1979. (2) 202/634-14131 between 8:15 a.m. andChairtnan's ruling on requests for the Amend:nent No.36 to IJeense No. DPR-3.00 p.m EST.
opportunity to present oral statements 63, and (3) the Commission's related and the time allotted for the Dated: AprG1.1980.
presentations can be obtained by a Safety Evaluation. A!! of these items are prepaid telephone call to the cognhant available for public inspection at the John C. Hoyta.
Advisory Commit:ee Monegement Oficer.
Designated Federal Employee. Mr.
Commission's Public Document Room.
va om e. ions rw m a.s Elpidio G. Igne (telephone 202/634-3314) 1717 H Street.N.W Washicaton.D.C.
enAn.a coca no es.es between 8:15 a.m. and 5:00 p.m EST.
and at the Oswego County OfSce Building. 46 E. Bndge Street. Oswego.
Dated April 1.teso.
New York 13128. A copy ofitems (:) and Advloory Canmntee on Reactor Jeha C.Heyte,
, m ma& &aked upon muut Advisory Committee Mar agement Oficen
.ddressed to the U.S. Nucleer ConYte nd C e S ctures:
ya o,,.
.,3,u o.e s.,i
- Regulatory Commission. Washington.
g8 amuse coca neo.ew D.C. 20555. Attention: Dircector, The ACRS Subcommittee on Concrete Division of Operating Reactors.
i and Concrete Stnictures will hold a IDocket No. 50-2201 Deted at Beenda.Ma: Sand &is 286 day J mieting on April:.:- 3.1980la Room omarch 19eo.
1167.1717 H St., NW., Washington, DC Magara Mohawk Power Corg For & Nuclear Regulatory Com ion.
to review " user needs" in structural Issuance of Facility Ucense engineering and the way in which these Amendment Mmu A.lppdito.
i chief.opemting Recetore EmachNo. A needs have been and are being met.
The U.S. Nuclear Regulatory Notice of this meeting was published
. Commission (the Commission) has Dieision of Operating Reactors.
In accordance with theyrocedures issued Amendment No. 36 to Faci!!ty ps o iaan rc.m ea :-
f March 19.1980.
cutlined in the Feders! Register on Operating Ucense No.DPR-63 to snusa coom ws.a Niagara Mohawk Power Corporation 6.
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ATTACHMENT B ACRS SUBCOMMITTEE MEETING ON CONCRETE AND CONCRETE STRUCTURES April 22 & 23,1980 i i Washington, D. C.
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ATTENDEES:
OTHERS ACRS Richard Orr, W. Offshore Power Systems C. Siess, Chairman J. W. Klingelhoffer IEEE P. Shewmon N. Nunley, IURI W. Mathis Noel T. Winter, IURI T. Pickel, ACRS Consultant James P. Allen, III, Stone & Webster M. White, Bruce J. Mann, Sen. Subcom. on N.R.
- 2. Zudans, J. G. Stampelos, ACRS Fellow T. McCreless, Staff E. Igne NRC B. S. Browzin, RES Carolyn Butler, RES J. F. Costello, J. J. Burns, RES, MERS C. W. Burger, RES Goutam Bagchi, RES, SRB Larry Shao, RES
- 5. P. Chan, NRR, SEB S. E.. Polk, NRR/SEB John C. Lane, NRR/SEB H. W. Lee, SEB R. E. Lipinski, SEB P. T. Kuo, ARR, SEB S. Kim, SEB D. C. Jeng, NRR/ DSS /SEB G. P. Tan, NRR/ DSS /SEB Frank Rinaldi, NRR/ DSS /SEB John 5. Ma, NRR/ DSS /SEB J. Martore, NRR/ DOR A. Hafiz, DSS F. Schaver, NRR T. Murphy, NRR l
K. S. Herring, NRR Howt.rd Wong5 IE/TP Gunter Arndt, OSD
ATTACHMENT C ACRS SUBCOMMITTEE MEETING ON CONCRETE AND CONCRETE STRUCTURES APRIL 22 and 23,1980 WASHINGTON, DC
- 4:~L APRIL 22,1930
- r APPROXIMATE TIME 8:30 a.m.
If INTRODUCTION I I.' RESEARCH PROGRAt PLAN 9:00 a.m.
e Overview and Individual Programs 10:25 a.m. - 10:40 a.m.
o..................'
BREAK III. TECHNICAL ASSISTANCE PROGRAM 10:40 a.m.
Structural Engineering Branch e
12:10 p.m.
Engineering Branch e
12:40 p.m.
Inspection and Enforcement e
1:10 p.m.
- LUNCH 2:10 p.m.
Systematic Evaluation Program Branch e
3:00 p.m.
BUDGET. qR IV 3:45 p.m. - 4:00 p.m.
e..........*.......*
BREAK 4:00 p.m.
V.
ACRS COMMENT ON FUTURE DIRECTION p
4:30 p.m.
C VI. ADJOURNMENT APRIL 23,1980 8:30 a.m.-
I.
CHAIRMAN'S(COMMENT 9:00 a.m.
II.
SSMtP - STRUCTURAL PORTION 11:00 a.m.
III. ACRS CAUCUS and DISCUSSION WITH STAFF M MD - 12:00 noon l
IV. ADJOURNMENT kW
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