STAND &,

A111Q5

NBSIR 81-2205

National Measurement Laboratory

Office of Measurements for

Nuclear Technology

Annual Report 1980 I

John D. Hoffman

Director

National Measurement Laboratory

H. Thomas Yolken

Chief, Office of Measurements

for Nuclear Technology

National Measurement Laboratory

U.S. Department of Commerce

National Bureau of Standards

Washington, DC 20234

i\

January 1981

Annual Report, Fiscal Year 1980

(October 1 , 1 979 - September 30, 1 980)

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81-2205

1981

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,S. DEPARTMENT OF COMMERCE

^TIONAL BUREAU OF STANDARDS

NBSIR 81-2205

NATIONAL MEASUREMENT LABORATORY

OFFICE OF MEASUREMENTS FOR

NUCLEAR TECHNOLOGY

ANNUAL REPORT 1980

John D. Hoffman

National Bureau of Standards

Library, £-01 Admin. Bldg.

WAR 3 0 1981

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Director

National Measurement Laboratory

H. Thomas Yolken

Chief, Office of Measurements

for Nuclear Technology

National Measurement Laboratory

U.S. Department of Commerce

National Bureau of Standards

Washington, DC 20234

January 1981

Annual Report, Fiscal Year 1980

(October 1 , 1 979 - September 30, 1 980)

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
f> • I’';

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M I ‘ I- .4
Preface

This annual report is a summary of the National Bureau of Standards (NBS)

Measurements for Nuclear Technology (MNT) Program for Fiscal Year 1980. The MNT

activities at NBS are divided into two programs: Nuclear Safeguards and Nuclear

Waste Management. The Nuclear Safeguards Program was the first to be initiated

near the end of Fiscal Year 1977, while the Nuclear Waste Management Program was initiated near the end of Fiscal Year 1980. However, NBS did make significant

contributions to the nuclear safeguards field in years past. For example, in the

1950 's, C. J. Rodden and other NBS scientists founded a laboratory for the measurement of nuclear fuels at NBS. This laboratory was later transferred to the U.S.

Atomic Energy Commission and became known as the New Brunswick Laboratory. In

addition, work by W. Shields and co-workers in the 1960 's established NBS as a world leader in the development of ultra-high accuracy mass spectrometry for

chemical and isotopic assay of nuclear fuels. NBS Standard Reference Materials

for the chemical and isotopic assay of uranium and plutonium provide the foundation

for nuclear safeguards measurements throughout the world.

In a somewhat different area of safeguards technology, J. Schleter and co- workers at NBS provided an entirely new approach to the problem by applying systems

analysis techniques. In the early 1970' s, they developed and implemented a technique that is known as diversion path analysis. Many other organizations are now

applying systems analysis techniques to safeguards problems.

In the mid 1970 's, interest in standardization of measurements for nuclear

safeguards was furthered by the recognition of a need for an NBS program in this area from many organizations. This recognition and support resulted in the

establishment of the Measurements for Nuclear Safeguards Program at NBS.

The Department of Energy (DOE) in late August 1979 invited the National Bureau

of Standards to consider the establishment of an appropriate technical assistance

program to meet the measurement standards needs of the waste disposal problem.

Because of the urgency of the request and the complexity of the problem, NBS

assembled a study group consisting of 13 experts in a variety of scientific and

engineering disciplines. The group was asked by NBS management to study the

problem in a three-month period (Sept. 15 - Dec. 15, 1979), to explore critical

questions, and to define an appropriate NBS technical program in a final report to

be completed and reviewed by March 31, 1980. The report was completed on March 31,

1980, and submitted to DOE. The goal of the NBS program stated in the report is to

provide a measurement base (including reference methods. Standard Reference Materials,

Standard Reference Data, measurement assurance procedures, and scientific laws and

concepts of waste behavior) to allow other organizations to (a) measure short-term

behavior, (b) predict long-term behavior, (c) choose acceptable disposal systems,

and (d) provide quality control of processing and assembly in nuclear waste management. The NBS Nuclear Waste Management Program was initiated in September 1980 and

is completely supported by DOE funds.

The MNT Program is one of several matrix managed efforts at NBS. The programs

provide a focus for the activity, both inside and outside NBS. The programs provide

funds and directions for needed technical work that is done within NBS Centers.

People remain attached to Centers but are funded for specific activities in a matrix

management approach. A program provides central organization for outside inquiries

and for distribution of results. Often programmatic focus can provide improved

assistance to outside agencies with measurement problems. The MNT Program is

operating in this manner.

1
We hope that this annual report will provide the technical conununity with

a view of the Program's direction. We encourage members of the community to

make recommendations to us concerning the program's future direction.

B. Stephen Carpenter

William P. Reed

H. Thomas Yolken

Office of Measurements for

Nuclear Technology

11
TABLE OF CONTENTS

Page

Preface i

1. Introduction 1

2. Personnel 4

3. Measurements for Nuclear Safeguards Program - A Technical Overview . . 7

A. Non-Destructive Assay 7

B. Destructive Analytical Chemistry 26

C. Bulk Measurements 32

D. Applied Mathematics 37

E. Safeguards Systems Studies 38

F. Users Guide, Safeguards Accountability Instrumentation and

Techniques 39

4. Measurements for Nuclear Waste Management Program - A Technical

Overview 40

A. Waste Forms - Leachability Mechanisms 40

B. Waste Forms - Research, Reference Materials Data and

Measurement Methods 40

C. Containers, Backfill and Mathematical Support 41

5 . Appendix

A. NBS Seminars on Measurements for Nuclear Technology 42

B. Committee Participation and Consulting Activities 42

C. Publications from Oct. 1, 1979, to Sept. 30, 1980 44

D. Talks from Oct. 1, 1979, to Sept. 30, 1980 46

E. Sponsored Symposia and Workshops 47

F. Office Chart 48

G. Functional Statements 49

H. NML Organizational Chart 50

I. NBS Organizational Chart 51

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1 . Introduction

The Office of Measurements for Nuclear Technology (OMNT) was established to

provide national measurement standards needed to safeguard nuclear materials.

In addition, during the past year, a task force of NBS scientists examined the

need for measurement standards in nuclear waste management, resulting in the

formation of a program in nuclear waste management. Thus, the OMNT now consists

of two separate activities. Nuclear Safeguards and Nuclear Waste.

Nuclear Safeguards

Introduction

Rapid and sensitive methods to detect the diversion of nuclear materials are an essential objective of the measurements for nuclear technology program. This

objective can be achieved with the aid of accurate and precise methods of measurement of nuclear materials at all phases of manufacture, use, and transfer to

maintain material accounting. Effective and universal measurement standards are required to attain the necessary accuracy of measurement.

The NBS program for nuclear safeguards serves three sets of clients : the

Nuclear Regulatory Commission (NRC) and the U.S. commercial nuclear industry; the

Department of Energy (DOE) (as developer of nuclear safeguards technology and as regulator of nuclear facilities operated for DOE) and U.S. Government -owned DOE

nuclear facilities; and the International Atomic Energy Agency (IAEA) and countries

that have nuclear facilities under the jurisdiction of the Non-Proliferation Treaty.

The FY 1981 NBS nuclear safeguards program is funded by DOE and the Department of

State (DOS)

Goals and Objectives

The goals and objectives of the NBS program are derived from the perceived

needs of the sponsoring agencies - to reduce the risk to the public from the

illegal diversion of nuclear materials by providing a common and accurate standardization basis for measurement of nuclear fuels. This goal is to be achieved for

all of the measurements that need to be made throughout the fuel cycle on a wide

variety of material forms. In order to meet this goal, our objectives are to provide measurement standards and services for the four major measurement areas for

nuclear safeguards accountability. These are listed below.

Tasks

To achieve these goals and objectives, three task areas are utilized that

combine similar technological resources of NBS. These three task areas are

(a) Bulk and Nondestructive Measurements for Nuclear Safeguards

(b) Chemical Measurements for Nuclear Safeguards

(c) Systems Studies and Statistical Analysis

Nuclear Waste Management

Introduction

In August 1979, DOE invited NBS to consider establishment of a technical

program that would contribute to the measurement standards foundation required

for disposal of nuclear waste. A group of NBS scientists was asked by the

1
management of NBS to examine the needs for measurement standards in nuclear waste

management and, if desirable, to recommend a technical program. The NBS study

(funded by DOE) was completed, approved by the NBS Executive Board, and submitted

to DOE on March 31, 1980. DOE staff have reviewed the NBS proposal and have provided a total of $1,850,000 to NBS to initiate a portion of the program in FY 1980

(last quarter) and FY 1981. DOE intends to increase the funding level in future

years to allow additional activities to be included in the program. NBS and DOE

will most likely consummate a Memorandum of Understanding in the nuclear waste

management area.

Goals and Objectives

The summary of the NBS report on nuclear waste management follows . . . The

National Bureau of Standards proposes to support the national program in nuclear

waste disposal by: assisting in the development of measurement techniques and

standards to assess stability, providing knowledge of factors controlling stability

of the waste package, determination and evaluation of data critically needed for

evaluation of alternative waste forms and packages, and development of measurement

standards and procedures needed for quality control. This is an appropriate role

for NBS for several reasons. First, accuracy is required in difficult measurements

that are essential to the solution of a national problem. Second, competence in

similar measurements on other materials already exists at NBS. Third, credibility

of results is extremely important; the traditional NBS measurement and standards

role of third party objectivity with no promotional or regulatory interest is

appropriate. Fourth, certain voluntary consensus standards are needed, as well

as regulatory standards; the existing extensive work of NBS in support of the

voluntary consensus standards system makes a good base for similar standards work

in support of nuclear waste disposal.

The strategy of the NBS program recognizes the need to disseminate existing

NBS capability, mainly in the area of short-term performance, and to concurrently

develop the new scientific basis needed for long-term prediction, and to provide

the additional basis needed for short-term performance capability. For example,

work is needed to improve the accuracy of existing leach tests and develop con- sensus on standard tests to determine short-term performance. This work is

critically needed but must be supplemented by work on the mechanisms controlling

release so that long-term predictions can be made. NBS will accordingly pursue

parallel and interactive efforts centered respectively on reference leach tests

involving chemical analysis and on the kinetics of long-term release. The NBS

strategy also recognizes the importance of collaboration with work already in

progress in a number of government, industry, and university laboratories. NBS

will make optimum use of its existing experimental facilities in carrying out this

work. NBS will concentrate on model systems using the same chemical compounds and

structures, but employing isotopes with no or relatively low levels of radioactivity.

Work on actual, high activity waste forms will be carried out in a cooperative manner

at existing hot cells in other laboratories.

With the foregoing considerations in mind, the overall goal of the NBS program

can be stated as follows: To provide a measurement base (including methods, data,

traceability to basic standards, and assurance procedures) and scientific laws and

concepts of waste behavior to support: (a) measurement of short-term behavior,

(b) prediction of long-term behavior, (c) choice of acceptable disposal systems,

and (d) quality control of processing and assembly in nuclear waste management.

The NBS program is developed in terms of work needed on each component of

the multi-barrier system and the need to monitor the system. The following

technical themes run through much of the work:

2
(a) the interactions between components of the system

(b) quantitative analysis of elements and phases

(c) stability of phases over relatively short times

(d) leach and corrosion rates over relatively short times

(e) mechanisms and quantitative basis of phase changes, mechanical

deterioration, leaching, corrosion, absorption, and transport

(f) predictive scientific laws and concepts to allow choice of disposal

systems

(g) test methods and procedures for quality control

Tasks

To achieve these goals and objectives, the NBS program on nuclear waste has

developed, for FY 1981, three tasks which combine similar technology resources of

NBS. These three task areas are

(a) Leachability Mechanisms for Waste Forms

(b) Nuclear Waste Form Reference Materials and Data

(c) Containers, Overpack, Corrosion and Backfill

3
2 . Personnel

The Office of Measurements for Nuclear Technology (OMNI) is in the NBS

National Measurement Laboratory (see organizational chart in Appendix). The

OMNT consists of two major programs: Measurements for Nuclear Safeguards and

Nuclear Waste Management. Each program is run by the Team Management concept,

which allows members from different centers or programs within NBS to help the

programs run effectively. At the present time, the OMNT interacts with four

centers in NML and two centers and the Continuous Process Technology Program in

NEL. The Management Team concept has been demonstrated to be a fruitful approach

to matrix management.

An FY 1980 organizational chart is shown in the Appendix, Section F.

Tables I and II provide a summary of the NBS-OMNT personnel.

4
Table I

Summary of NBS Personnel Involved in

the OMNI Safeguards Program

Technical or Area

A. Bulk Measurements

Density

Flow

Volume

Mass

Process Measurements

Principal Investigators

G. Baumgarten, D. Cooper,

A. Gaigalas, J. Houser,

E. Johnsen, F. Jones,

B. Robertson, J. Whetstone,

T. Yeh

B. Destructive Chemical and Isotopic Assay

Chemical Assay

Mass Spectrometry

Alpha Spectrometry

Moisture Determination

C. Non-Destructive Assay

Calorimetry 1 Gamma Techniques ? Neutron Techniques;

D. Statistics

Measurement Assurance Programs

Reference Materials

Calibrations

In-Plant Error Analysis

E. Safeguards Systems Studies

F. User's Guide, Safeguards

Accountability

UF6 Mass MAP

J. Fassett, E. Garner,

J. Gramlich, F. Jones,

W. Kelly, H. Kingston,

L. Lucas, L. Machlan,

J. Moody, L. Moore

D. Bakshi, J. Behrens, C. Bowman,

A. Carlson, S. Carpenter, T. Cheng.,

J. Colwell, D. Ditmars, R. Fleming,

M. Ganoczy, D. Garrett, R. Johnson,

L. Lucas, M. Meier, T. Mitlehner,

R. Schrack

H. Ku, J. Lechner, W. Liggett

C . Spiegelman

S. Bologa, M.D.K. Maltese,

J. Schleter

E. Johnsen

5
TABLE II

Summary of NBS Personnel Involved in

the OMNT Waste Program

Technical or Area

A. Waste Forms

1) Leachability Mechanisms

Concepts - Theory

Radiation Effects

Transport, Thermochemistry, \ Microstructures f

Mechanical Properties

2 ) Research and Reference Materials,

Data Measurement Methods

Phase Diagrams of Relevant Ceramics

Leachability Research Materials (Glass)

Leachability Reference Test Methods

B. Containers, Overpacks, Sleeves

Corrosion Mechanisms 1 Data and Methods > Feasibility of Long-Term Deep Test)

C. Backfill

Mechanisms \

Research Materials > Data and Test Methods )

D. Mathematical Support

Statistical Engineering

Submodeling

Principal Investigators

R. Mountain, R. Munro

T. Cheng

R. Roth, A. Franklin

S. Wiederhom

R. Roth

W. Haller, D. Cronin

H. Kingston

J . Kruger

F. Yokel, R. Chung

H. Ku

J . Fong

6
3. Measurements for Nuclear Safeguards Program - A Technical Overview

A description of the technical activities in each of the Program’s four

areas is given in this section. In addition, accomplishments during FY 1980,

the third full year of the Program, are reviewed.

A. Non-Destructive Assay

The NBS effort on standards for non- destructive assay (NDA) of nuclear

materials is motivated by the need for reliable, accurate, timely and economic

methods for the measurement of special nuclear materials. A wide variety of

activities are being carried out in NBS laboratories to fulfill this objective.

The activities may be grouped into thbee major categories: referenc|H!(ft^t^gd$,,T;

standard reference materials, and data development and calibration.

aoiTso H3aii

Cl) Reference Methods

3 Q0HTA0 OTOHq j Reference methods are methSd^jliaVi*i^V<l^ffldrifit rated precision and

] |

accuracy. Due to their complexity, these techni^^s are general^-suit^d-i- - ---^ y only for a specially equipped laboratoijyT 'ffieagT^^eg^aggtjl^dsr- i ; i are used to characterize reference' materials or a!s^ references^ ft^j = '

j and calibrating simpler techniques tha

(a)

nomaoa-x o

are inherently less fccqii’jijt

sensitive nTSt

Resonance Neulron jlac

Advahces in data gatherin

After

and in analysis have t spjn 4^?^^ | | 5nt of a h^gh resolution one-dimeij$i|o^^i^^bsxit5b^^^

Jut r6ir'<tet|iqt(^ an^ thi j successful demonstration of iljtjs; to'" ;' analyze fresh fuel pei'Tff^,‘^i‘trwa > obvioT|is that the speed of datp.; |g|3^^tang

could be greatly in proved by the ievaAopijient of a two- dimens ion4il| ;d^^e$or^ In

collaboration with Oak Ridge Nati >nal Lalporatory, a two-dimensi^hj^lj^Os^tron

*1 ! sensitive proportional counter wa> developed. Initial tests on

j tii|e phavq

j

| shown high resolution 1.0 mm) liicl f|ur|:her dev^^pment on the j | ^dei^ay

to improve the speo d of data takiig. ^

detector, shown in ^Fi’gm’ e ~1, hao been P vxtffgTeh^^jtype' af t\«p -d:|iiijen^^.^,^...| . ,

jdeveloped iit’ cooperation lifilljhp^^^ace

Science Corporation. A small detectoiji about 1" in diameter diameter havinig havinig aififesolution Dissolution

of about 0.1 mm has been developed th^^ utilizes a multi-ch4inei; j^lb^;^0 lectron

amplifier. Plans for testing the deviice are nc^

^^^derwav

i L

lice

Computer calculations have shown that inhomogeneities in sample

thickness, that would cause large errors in the assay of constituents, ican be com- pensated for and the error reduced analysis

of the resonance line in the absorption spectrum. The c^pencfince" of this effect

on sample thickness is shown in Figure 2. With l^is p^lc

samples of spent fuel have been measured treat

_

of fuel as one analysis area. Figure 3 shows th^‘^'trr43smi*^‘^n’1^ettT^ obtained

for the two samples. Analysis of the data is now underway, but a casual examination shows quite obvious differences in isotopic composition between the two

samples. Table 1 lists some of the more obvious examples. The two samples are from the same fuel rod. One sample is taken from the end of the rod where the

neut¥bif"^irk^^^ af the-.^rod

where tfhe^^d’t^bii^^f is- ^trie ^tiraWbifif^iC isotope

buildup is greater in the center cut, an^ the is

less on the end cut. The development of this technique should be a valuable tool

in spent fuel analysis for the safeguards program to determine reactor history

and fuel rod composition.

This work is being performed in the Center for Radiation Research

under the sponsorship of NRC.

a

7
SCINTILLATOR w FIBER OPTICS

PHOTO CATHODE

i

PREAMPLIFIERS

i>

POSITION

ANALYZER

O X- POSITION

O Y- POSITION

RESISTIVE ANODE ENCODER

MICROCHANNEL PLATE

ELECTRON MULTIPLIER

Figure 1. Schematic of two-dimensional neutron detector. The scintillator

material is 1.0 mm thick enriched Li glass. The system has a dead time of 8 microseconds.

8
*^mox ^0

Figure 2. Error induced in sample analysis by non-homogeneity of sample.

The graph shows the error induced by a sample whose density

varies by a factor of ten. The maximum density is Pmax atoms

per bam, and the peak cross section is Qq barns/atom. The curve labelled Ri shows the error obtained by conventional

analysis. The curve labelled R 2 shows the error obtained when

a two-component analysis is used.

9
-ICO

Figure

3.

Neutron

transmission

of

spent

fuel

samples.

The

upper

curve

shows

the

neutron

transmission

fora

sample

cu

from

the

center

ofa

spent

fuel

rod,

the

lower

curve

from

the

end

of

the

same

rod.

The

abscissa

is

neutron

energy

from

1.0

eV

to

20.0

eV.

The

resonances

are

identified

in

Table

1.
Table I

Resonance

in Fig. 3

Neutron

energy (ev)

Atom Remarks

a 1.06 Less in end cut

b 2.70 Much less in end cut

c 5.5 236„ Less in end cut

d 5.9 ^''Ipu Less in end cut

e 6.67 238„ Same in both

f 8.0 Less in end cut

9 8.8 235^ More in end cut

h 10.2 2^0pu Less in end cut

i 10.9 239pu Less in end cut

j 11.6 235y More in end cut

k 11.9 239pu Less in end cut

1 12.3 235^ More in end cut

m 14.4 Less in end cut

n 19.3 235„ More in end cut

11
(b) Van-de-Graaff Techniques

A program to develop Van-de-Graaff based measurement systems

for safeguards standards has been completed in collaboration with the Los

Alamos Scientific Laboratory (LASL) . Dr. Michael Meier of the Neutron Physics

Group has been at LASL since December 1978. Dr. Meier has been working on two

major programs during the past two years at LASL. The first of these areas was

to develop a technique such that a User's Guide for the Van-de-Graaff based

Small Sample Assay Station (SSAS) with the associated support hardware and

software could be produced. This Guide is to acquaint potential users of the

Van-de-Graaff based SSAS with the associated support hardware and software.

The general operation of the SSAS is described in Ref. 1. In brief, the proton

beam is pulsed with a repetition rate of 10 s The 100-millisecond period is

divided into four intervals:

1. 0-35 ms--beam on target for neutron production, rate

10^°-10^^ n/s and SSAS preamp biased off;

2. 35-50 ms--beam off, SSAS preamp biased on and gain

stabilizing;

3. 50-90 ms--beam off, SAS preamp gain stabilized and scaler

electronics counting delayed neutrons; and

4. 90-100 ms--beam off, SSAS preamp biased off and scaler

electronics gated off.

The interrogating neutron flux is monitored by a cadmium- covered ^He proportional

counter (^He) mounted on top of the SSAS, a cylindrical fission chamber (FC) that

surrounds the sample position, a modified long counter (MLC) , and the proton current incident on the neutron producing target. The first three of these signals

are supplied to integral discriminators with biases set between the low pulseheight tail and the thermal peak (^He counters) or fission fragment peak (fission

chamber). The target current is supplied to a commercial current integrator, and

the output pulses, proportional to total charge, are scaled in a scaler board [2]

along with the discriminated monitors' pulse trains.

The SSAS is a very efficient detector based on 39 moderated ^He

proportional counters. During the time that its preamp is biased on and stable,

logic pulses corresponding to ^He(n,p)T events are supplied to another channel

of the scaler. Samples are assayed by measuring the ratio of SSAS events in the

delayed neutron counting period to the interrogating neutron flux. A rabbit

system is used to transport the samples from the Van-de-Graff console to the

irradiation position in the SSAS. An associated clock is started when the sample

is transmitted and an "enable acquisition" dc level (EAL) shifts from zero to

five volts after a preset interval in which the irradiated sample comes to

equilibrium.

The Van-de-Graaff LSI-ll-related hardware is comprised of the

LSI-11 chassis, the interfaces and scaler board, a CRT terminal, and a LA180

printer. There are two types of software control for this system, the

automatic program control and the semi-manual control by the console keyboard.

The second area was the development of procedures for measuring the hydrogen

content of unfired fuel rods using a ^^^Cf hydrogen monitor and the issuing of

a User's Guide for the monitor.

A ^^^Cf hydrogen monitor has been used to determine the hydrogen

contents of 144 unfired ("green") fuel rods being circulated in the New Brunswick

Laboratory fuel measurement evaluation program. The monitor was calibrated with

12
standards fabricated by LASL analytical chemistry group CMB-1. Measurements were

made relative to these standards and overall accuracies of were achieved.

A major problem in the fast neutron assay of High Temperature

Gas-cooled Reactor (HTGR) unfired ("green") rods is the presence of hydrogen

(H) , which moderates the average energy of the interrogating flux and thereby

changes the response of the system. Preliminary work has shown that this effect

enhances the response by about 25% for the 150-mg H content of the rods and 10%

for the 450-mg H content of the polyethylene encapsulation provided for the HTGR

fuel measurement evaluation program, sponsored by New Brunswick Laboratory (NBL)

To make this correction with confidence, accurate measurement of the hydrogen

content must be made. To this end, the hydrogen monitor [3] has been calibrated

and used to measure H content of these rods.

The rods are right circular cylinders 1.4 cm in diameter and 5.0 cm high composed of TRISO-coated UC 2 and ThO beads embedded in a carbon matrix.

For the intercomparison each rod is encapsulated in a sealed polyethylene vial

The hydrogen monitor has been calibrated for measurements in the

vicinity of 600-mg hydrogen. With the current calibration and standards, the

estimate accuracy is +4.5 mg, which is based on the difference in assay results

for the same unknown for two different standards and measurement precisions.

Before proceeding with work that improves the precision of the monitor, more

work will need to be done to remove a n|^3-mg discrepancy. Likely candidates for

investigation are the exact form of the response, which is likely to be more

complex than the simple linear response, and use of calibration standards, which

more closely match the rods.

The software and procedures to be used for calibration and running

of the ^^^Cf hydrogen monitor have been documented in a User’s Guide. Computer software was developed for use with the DEC LSI-11 using the Version 3 operating system.

This work is being performed in the Center for Radiation Research

under the sponsorship of DOE.

References

[1] Adams, E.L., Bourret, S., and Meier, M.M., "Small Sample Assay

Station Users' Guide", to be published as LASL (LAMS) Information Report.

[2] Bourret, S., et al., "Model 516 LSI-11 Six-Channel Scaler",

to be published as part of Ref. 1.

[3] Meier, M.M., and Adams, E.L., "HTGR 'Green' Rod Intercomparison - I. Hydrogen Assay", to be published as part of Ref. 1.

(c) Neutron Tomography

Another major NDA effort is to develop the methodology for highaccuracy measurements and establish reference standards using resonance neutron

tomography with reactor-produced neutrons.

The efforts devoted during fiscal year 1980 for the resonance neutron

tomography portion of the NRC supported nuclear safeguards program were (1) furthering

and continuing development of software programming and the library data set; (2) the

finalizing of hardware designs and subsequently the letting out of construction bids;

and (3) the use of three low enrichment U-235 fuel pellets to experimentally verify

the "resonance neutron self-indication effects" with the NBS Reactor.

The need for continuing development of software programming and the

library data set was evident as Eq. 3 in the OMNT Annual Report for 1979 indicated.

13
-Z a„ (E)X,

a„ (E)dE

4 4

= S? - I K.,X. + I L..X. + Z M...X.X.

k . , ik 1 . 1 ik 1 . , . ijk 1 j 1=1 1=1 ijtj '

° E A (E)a (E)dE; e A (E)a^ (E)Qp (E)dE;

^k * i ^k

E 1/2 A (E)a^^(E)ap (E)dE; and e 1/2 4 (E)a^ (E)a^_ (E)Op (E)dE.

%/ i k i j k

is proportional to the detector response with no sample.

where S,

'ik

To ensure that all X.'s would have unique values that are orthogonal to one another, i.e., X. cannot be a function of X. or their combinations. This

requires that th^ cross sections as functioM^of neutron energy (mainly resonance neutrons) have to be clearly and distinctively described for each

and every fissile isotope involved. Our present library data set utilizes

200 cross section data points for each fissile isotope. Their effects will

be determined by comparing theoretically calculated and L^, values with

experimentally measured ones which is by fitting the experimentally generated

curves of fissile sample thickness vs. fissile detector reaction rate for each

different type of fissile material.

In order to solve the multiple non-linear equation set of the

above kind, a derivative method was used. An example involving composites of

three types of isotopes is illustrated here.

S^CXj.Xj.X,) = S^(xp * S^tXj) * S^CXj) -

25,^ . . (1)

where Xj, X2, X3 are the thicknesses of three different types of fissile isotopes,

and M. is defined as before ijk

M

ijk 1/2/4 (E) a,^ (E)o^ (E)Op (E)dE

i i k

If we introduce a filter of known thickness and type dX^ in the neutron beam,

then

S^(Xj + dXj,X2,X3) = Sj^CX^ + dXp + S^(X2) + S^CXj) - 2S;j

( 2 )

( 2 ) - ( 1 )

dS^(dxp . S^(X^

= S,(Xj

+ dXj.Xj.Xj) - S^CXj.Xj.Xj)

* dxp - S^(xp * 2 (Mj 2„X2 . Mj3^X3>dXj ( 3 )

14
dS^(dXi) = * (4) ''"l2k>‘2

* «13kV‘*’‘l

where H -K.^dX. + L.^(dX.)2.

The non-linear equation set (1) is now linearized

dS (dX ) c. ^3)4- = 2dx7 * hk’^l

" «12k’‘2* «13k='3

(5)

The software program for solving Eq. (5) has been incorporated into the VAX-11/780

computer.

The detail design of the reactor-based resonance neutron safeguard

experimental system was completed last April and has successfully gained the

approval of NBS Reactor Hazards Evaluation Committee. The NBS Shops Division is

responsible for the construction of the system and the letting of bids to private

contractors. The scheduled completion date is February 1981. The collimator is

made up of nesting tubes of various diameters so the beam size can be changed from

1/4" (0.64 cm) to about 2 inches (5.08 cm) to facilitate faster count rates with

compromised resolution for larger containers and to accommodate neutron radiography

use. The retrieved collimator tubes will be stored in an auxiliary shield.

In order to verify the resonance neutron self-indication effect

with the NBS Reactor facility, an experiment was conducted to quantitatively

determine the U-235 and U-238 contents in three nuclear fuel pellets supplied

by General Electric Wilmington Manufacturing Department. The known information

is as follows:

Isotopic U-235

enrichment % Density Length Diameter

3.9572 88.15 95.9243 0.432" 0.410"

2.5174 88.168 96.56 0.4395" 0.410"

1.194 88.14 95.52 0.434" 0.410"

A horizontal neutron beam of 1/4" (0.64 cm) diameter was extracted

from the NBSR core on port BT-7. The thermal neutron portion of the beam was removed by using a 0.04" (0.102 cm) thick Cd sheet as filter. The filtered beam

was then transmitted through the fuel pellet and detected by NBS double fission

ionization chamber detectors [ 4 ]

.

The experimental setup and fuel pellet holder are shown in Figure 4.

The holder was made with a lucite block of approximately 15 cm long, 5 cm wide and

1 cm thick. Four holes were drilled to accommodate the three fuel pellets and a blank reference hole. The electronics block diagram is shown in Figure 5.

The three fuel pellets, along with the blank hole, were scanned

by the neutron beam and detected with U-235, Pu-239 double fission chamber

detectors and then with U-235, U-233 detectors. The reason for using Pu-239 and

U-233 detectors was that the fission cross section for U-238 was very small.

15
E

-cO • (U z

*3- I — H iH M = fl

(4-t C0

V4

(0 PD

"TOa«

(0 4JO

JZ

CO

(U

(1) u

CO

cxo 0 iJ u 0

r» o o• rH O 0 W U (1) fHO m 43

»< 3 0 O U >M

ir> 4) •H

4-1

O ««-l o o

43M 4-1

UX

>. 4J

•o o

<uX* c

(U o > -H O 44 O -H

(0 0) o

V4 (X

«0

0) (U 43

*J

H

•Ho3 • tH oj

4-1 U-l 0) o 0> 0 w o u

OJ 0) 4J

4-1 0) 43 -

•H

B cn

rt 'O CM

4J <; o

(0 4J I a o o

>-( o o

•H fH 0 iH

•H

<0 >

>sst

43 =«t: O *0

(U 3

iH C0 fHO » M CO

•U sfe co • U CM

=::» 0) 43 mV • fH fH CO fH O 4J •H a 0) 3 f*

0) • 0) 4J xi a

•H 0) U 4J 01

Mo

CO *H H 43 O 44

44acM

<U 0

4J

U

CD •a to c ® O CO

'0

<u

(/> to <

f4

0) T3

rHo

a:

+4

0)

<u o0)3

tx§

<ucxoo

I/) (D iH

<u HCO CO cr> u

CO CO 4^ 4-> •H CM U

4-1 1 •H 3 43

Xl cw 44

CO 0) Xi 43 T3 0 • o 0 C O

44 3 3 o 43 CM <u 0) O m O u

44 CO fH 3

0) 3 CM • bO Q fH 1 •H 43 C3 44 tu 3 3 3 O O 3

•H T3 CO 43

CO CO CO

CO CO CM

•H CO 1 •o a 3» u • • .. CO u

16
Figure 5 . Each side of the dual fission chamber is monitored

independently by a triple-scaler pulse-processing

system as shown here. The integral discriminator

counts, Sl and Sjj, are the primary (redundant)

counting data. The relative positions of the

discriminator levels Vl and Vy to the peak of the

pulse-height distribution, Vpg^ are established

with the aid of the multi-channel analyzer. The

SCA count Sq(^ provides a sensitive gain check;

VgC =1-37

17
A count rate of > 1000 cps was obtained using very thin fission

foil in all detectors, thus no corrections were made for detector dead time,

self-absorptions , and background noise. A total count of > 50,000 was accumulated for each data point.

The equation for U-235, U-238 mixed composition sample says

S, == S - K..X. + ik 1

2

E L

i=l

X.^ + ik 1

E M. X.X.

. . ijk 1 1 i=j

( 6 )

where i can be U-235 or U-238 and K can be U-233, U-235 or Pu-239.

If the neutron flux c|) (E) is known, one can then calculate the

, K.j^'s, L.j^'s and thus evaluate U-235 and U-238

three pellets using ine measured values from either the

U-235, Pu-239 detector set or U-235, U-233 detector set. Another approach is

using two fuel pellets as known standards, and if we further neglect the contributions from the second order terms, then one can experimentally determine the

various K.j^'s and thus the first order approximation for the U-235 and U-238

contents in the third pellet. The dropping of second order terms will introduce

an error 'v 15% for a sample thickness of 1 mm.

coefficients S°

contents in all

The following table lists the measured U-235 and U-238 contents in

grams in the third pellet as compared to the known quantities.

Known Measured with Measured with

quantities* U-235, Pu-239 detectors** U-233, U-235 detectors**

U-235 0.2174 0.185 0.03 0.193 0.03

U-238 5.2764 5.581 +^ 0.05 5.476 +^0.49

*Corrected for 1/4” neutron beam size. ^ **Errors were estimated second order effects.

The measured U-235 content in the third pellet is about 11% of

the known U-235 quantity when the U-233 and U-235 detectors set are used and

about 15% with the U-235, Pu-239 set. The accuracies for the measured U-238

content in the third pellet are 4% and 6%, respectively, for the two sets of

detectors. The fact that all neutrons with energies below 0.5 eV were filtered

out in the beam caused the Pu-239 detector to perform less satisfactorily

relative to U-233 and U-235 detectors, since 60% of the resonance strength for

Pu-239 lies in the 0.3 eV region. Nevertheless, the results indicate a reasonably accurate estimation of U-235 and U-238 contents can be obtained in

a very short time (< 1 min.) with the self- indication method with counting

statistics of 0.1%.

One also sees the need for incorporating the second order terms.

Presently we are preparing a set of standard Pu-239, U-235, and U-238 discs of

various thicknesses from NBS Standard Reference Materials which will be used in an upcoming experiment to measure cj) (E) as well as these first order and second

order coefficients. This will afford a much more stringent test of our methodology and reduce the measurement uncertainty to less than 1%.

18
In summary, it would require approximately one day to inspect a nuclear waste container approximately the size of a gallon paint can. This

conclusion assumes that it would require 110,000 transmission measurements with

a resolution of 4 mm and 3% counting statistics. The assumption is made that

the container will be scanned at 64 points in a plane orthogonal to its axis.

The container will be rotated in two-degree increments following each orthogonal

64-point scan. Following each complete 180° rotation cycle, the container will

be stepped axially and the process repeated for a total of 20.

The amount of time needed for the entire interrogation, together

with resolution and counting statistics, can be greatly improved by incorporating

a linear series of detectors and a reactor power of 20 MW.

This program is being carried out in the Center for Materials

Science under the sponsorship of NRC.

References

[4] Grundl, J.A., Gilliam, D.M., Dudey, N.D., and Dopek, R.J.,

Nucl. Tech. 25, 237 (1975).
(d) Calorimetry

The overall goal of the calorimetric activity is to provide

measurement assurance and traceability to National Standards for calorimetric

measurements made in the industrial assay of plutonium-bearing solids. This

activity aims at* the establishment of an automated calorimetric measuring

system which will be used to periodically check the certified power of encapsulated plutonium heat sources submitted by major industrial producers.

Major steps were taken in FY 1980 to realize the NBS goal of

providing traceability to National Standards for calorimetric measurements made

in the industrial assay of plutonium-bearing solids. These included (1) further

testing of a Mound-designed heat-flow calorimeter, together with an automated

data acquisition system (this included power measurements on two Mound-fabricated,

encapsulated plutonium heat standards) ; (2) design and start of construction of an NBS heat-flow calorimeter; and (3) preparation of an NBS "General Reference

Material" Report of Investigation to accompany Mound- calibrated plutonium heat

standards

.

(1)

The twin-bridge, heat-flow calorimeter obtained previously on loan from the Mound facility was tested in measuring the total decay

power of two calibrated plutonium heat sources (nominal powers 0.25 W and 4.0 W,

respectively) . The sources were loaded automatically, and calorimeter data were recorded with an automated data acquisition system built around a Hewlett-Packard*

9835 desktop computer. The NBS power data for both sources had a range of 20 ppm

and a standard deviation of about 10 ppm. They agreed with the Mound predicted

powers for these sources within the combined measurement uncertainties of NBS and

Mound

.

(2) Design specifications for an NBS twin-bridge, heat-flow

calorimeter were developed, using NBS experience with the Mound calorimeter as a guide. While the gross physical features and operating principles of the NBS

calorimeter follow the Mound design, some changes in construction materials, such

as use of stainless steel for all submarine parts and use of 0-rings instead of

gasket seals, were used to improve the reliability. In addition, the calorimeter

was designed to by symmetrical, so that either of its two sensing chambers could

be used as a reference chamber. The main calorimeter body has been completed, and

we are presently constructing the thermal sensing elements, including heaters and

resistance thermometers.

(3) In order to establish traceability to national standards

for calorimetric heat-flow measurements in assaying radioactive materials, a service similar to the one offered by NBS to the radiopharmaceutical industry

has been proposed. This is essentially a Measurement Assurance Program (MAP) in

which traceability to national standards is established through a programmed

exchange of measurement artifacts between major suppliers (in this instance, of

calibrated radioactive heat sources) and NBS. As a first step in this direction,

power measurements have been carried out on three Mound-calibrated heat standards

in an NBS ice calorimeter, and it has been determined that the NBS and Mound

*Certain commercial equipment, instruments, or materials are identified in

this paper in order to adequately specify the experimental procedure. In no

case does such identification imply recommendation or endorsement by the National

Bureau of Standards, nor does it imply that the material or equipment identified

is necessarily the best available for the purpose.

20
measured powers are in agreement within their combined uncertainties for all

three standards. Cooperative efforts between Mound and NBS scientists, together

with the Office of Standard Reference Materials, have produced a "General

Reference Materials" Certificate (GM-10) which documents these NBS/Mound

intercomparisons. Mound will be authorized to distribute this certificate

(together with its own calibration certificate and data) , along with each newlycalibrated source it provides. A copy of the NBS certificate for GM-10 appears

as Figure 6. As soon as the NBS heat-flow calorimeter is operational, a formal MAP

between Mound and NBS covering calibrated plutonium heat standards will be started.

This work is being carried out in the Center for Thermodynamics and

Molecular Science under the sponsorship of NRC and DOE.

(2) Standard Reference Materials for NDA

(a) U-235 SRMs

A major portion of the effort in this Sub-Task has continued to

be the development of the low-enriched UaOe NDA Gamma-Ray Spectrometry NBS SRMs.

This effort has been a collaborative one with NBL, LASL, NBS and the Euratom

Laboratories of JRC-Ispra, CBNM and KfK. During November 1979, a meeting was held at CBNM in Geel, Belgium, to review the results from each organization on the pre- experiment study, as well as to finalize the procedures and measurements

needed for the certification of the SRMs.

The final design of the aluminum containers for the material was approved (Figure 7) , and the production of the 900 cans needed was done by the

NBS Shops. Upon completion, these containers were then shipped to CBNM for

critical dimension measurements and filling with low-enriched UaOe. The filling

of containers with the isotopic standards began with the 0.318% material,

and continued in the order of increasing enrichment (0.7128%, 1.943% and 2.950%).

The 4.5% enriched material, which is to be included within the set of Reference

Materials, has not arrived at CBNM.

Prior to the canning of the material, 13 (1-gram) samples were

taken from each isotopic enrichment batch for mass spectrometry analysis, and

one (20-gram) sample was taken for the ^^^U/U determination by gamma- ray

spectrometry. In addition, each 20-gram sample will be sent to NBL for uranium

assay. A set of ultrasonic devices will be placed in the top of each can after

filling, and then a representative number of each batch will be sent to NBS for

critical evaluation by gamma-ray spectrometry.

Effort also has been devoted to investigating the contribution of

^^®U decay daughter products (^^“^Pa and ^^**"'pa) to the 185 keV gamma-ray line

observed from low-enriched samples. This study has continued through the use of uranium oxide samples of known isotopic abundance. Gamma- ray spectroscopy has been performed on 11.5-gram samples whose isotopic abundances

ranged from 0.0004% to 0.7198%. This isotopic range was chosen because the

contribution from ^^**Pa and ^^‘^"'Pa is most significant.

In addition to the gamma-ray spectroscopy, these samples are to

undergo chemical separation, since secular equilibrium exists. The uranium is

separated from its decay daughter products, thorium and protactinium. After

separation, the two fractions (uranium and thorium-protactinium) are then

measured by gamma-ray spectrometry. By monitoring the uranium fraction over

21
Figure 6

Special Report

GM 10

Encapsulated Plutonium Heat Source

Introduction

The enclosed encapsulated plutonium heat source provides a convenient, measured standard for calorimeter

calibration [1] in the calorimetric assay of plutonium-bearing solids. This report summarizes the NBS

measurements made on this reference material. The reference is produced and certified by the Mound Facility*,

Monsanto Research Corporation, Miamisburg, Ohio.

Description of Source

This heat source, fabricated and calibrated at the Mound Facility, consists of a doubly encapsulated sample

of plutonium-oxide. The sealing of both inner and outer capsules has been carried out using documented and

reproducible welding procedures. Nondestructive testing (radiography and He leak tests) has been conducted

to ensure the integrity of each capsule. Since the active materials are largely alpha-particle emitters, helium gas

will accumulate within the inner capsule. The capsules have a conservative design life of five years. The lack of long-term compatibility and creep data for the materials of construction precludes the assignment of longer

working lifetimes to the sources at this time. Therefore, it is strongly recommended that this source be returned

three years from the date of receipt to the Mound Facility for reevaluation and recertification. This source should be handled with the normal precautions for alpha-particle emitters and stored in the container provided

when not in use.

Certification

This source has been calibrated at the Mound Facility using Mound heat-flow calorimeters and electrical standards traceable to the National Bureau of Standards. A separate certificate issued by the Mound Facility

accompanies this reference material. Selected Mound plutonium heat sources similar to the one accompanying

the Mound certificate have been independently measured in a precision Bunsen ice calorimeter at NBS. riie calibration results accompanying that certificate are in the form of computer printout and microfiche giving

the decay power calculated from these measurements, day-by-day. for a three-year period after the calibration.

Also included are the physical parameters of the source including materials of construction and measured

radiation dose rates.

•Mound I acilily is operated by Monsanto R«earch Corporation for the U.S. Department of Energy under Contract No. DE-AC04-76-

DI>(XX)53.

22
Figure 6 (continued)

NBS Measurements on Mound-Encapsulated Sources

Each measurement in a precision Bunsen ice calorimeter reflects the average (unweighted) of at least 10 independent determinations of heat flux (power) for a single source. Three such measurements were carried out on Mound sources of nominal power, 0.23W, 1.5W, and l.OW, and are summarized below. The first two are documented extensively in [2]. Mound Source Designation

0.23WB 1.5WB l.OWK

Mound Predicted Power“[W] 0.22544 1.44942 0.97027

NBS-Measured Power* [W] 0.22517 1.44936 0.96996

Number of NBS Measurements 16 19 11

sn,‘’ m 0.00005 0.00004 0.00034

Estimated NBS Overall Uncertainty‘S [W] 0.0003 0.0007 0.0014

*] ndividual data for each source calculated for a single time mid-way through the measurements scries for that source. = Computed standard deviation of the mean. 'Sum of maximum conceivable systematic errors and 999c confidence limits for the mean.

At NBS measurements were carried out by D. Ditmars of the Chemical Thermodynamics Division and at Mound Facility by K. C. Jordan, Senior Research Specialist.

Packaging and reshipment of this source to the Mound Facility for testing and recalibration must follow all applicable Department of Transportation, U.S. Department of Energy and/or U.S. Nuclear Regulatory

Commission regulations. All shipments should be addressed to:

C. L. Fellers. Group Leader

Safeguards Research and Development

Monsanto Research Corporation

Mound l-'acility P.O. Box 32

Miamisburg, Oliio 45.342

[1] ANSI Standard NT5.22-1975. “Calibration Techniques for the Calorimetric Assay of Plutonium-Bearing

Solids Applied to Nuclear Materials Control'*, available from American National Standards Institute. 1430 Broadway, New York, New York 1001 S.

[2] D. Ditmars. Inti. .1. Appl. Radiat. Isotopes 22> (1976).

23
080 !

M-Q* ro»

24

i

Figure

7.

New

Aluminum

Container

Design

Drawing
time, an indication of the 185 keV gamma- ray line buildup reflects the protactinium interference due to decay, while the thorium-protactinium

fraction provides more quantitative information based on the protactinium decay.

This work is being carried out in the Center for Analytical Chemistry

under the sponsorship of NRC and DOE, with statistical help from the Center for

Applied Mathematics.

A commercially available, pure- germanium detector has been ordered,

evaluated, and accepted. This detector is presently being calibrated and further

tested for stability in preparation for its use in the certification of the NBS

Plutonium Isotopic Reference Materials, particularly the NDA standards.

Much discussion and information collection has been carried out,

both individually and at group meetings, to determine more accurately the needs

of the national (and, to a lesser extent, international) safeguards community

for plutonium Standard Reference Materials (SRMs) . A meeting of representatives

from all of the major U.S. facilities involved was held at NBS on October 15 and

16, 1980. At that meeting the needs and position of the U.S. safeguards community

were defined in preparation for a later meeting to discuss joint international

efforts to certify these SRMs on an international basis.

This work is being carried out in the Center for Radiation Research

under the sponsorship of DOE, with statistical help from the Center for Applied

Mathematics

.

(3) Data Development and Calibration

(a) Radioactivity Program

The half-life of ^**^Pu has been followed by measuring the ingrowth of ^“^^Am in a sample of ^**^Pu purified in March 1977. 47ra(LS)-Ycoincidence and -anticoincidence counting methods have been used. The results

to date remain consistent with a half-life of 14.35 ^ 0.15 y. It is planned

to measure the sample periodically for several more years.

The half-life of ^**°Pu is being determined from measurements of

the total alpha-particle-emission rate of a well- characterized sample of ^**°Pu02 . This ^‘*°Pu02, prepared at the Los Alamos Scientific Laboratory, has been provided

to several national laboratories for measurement of the ^“*°Pu half-life as part

of their participation in the DOE Half-Life Evaluation Committee. The results

of the measurements are to be published jointly, as was the case with the previous ^^^Pu half-life study.

This work is being carried out in the Center for Radiation Research

under the sponsorship of DOE, with statistical help from the Center for Applied

Mathematics

.

(b) Fission Track Monitor Evaluation

One of the activities completed within NBS during the last fiscal

year was the field testing and evaluation of a fission track reactor power

monitor for the International Atomic Energy Agency (IAEA) . The purpose of this

task was to evaluate the capability of the track-etch monitor for providing an independent record of the nuclear reactor's power history and to provide information concerning the neutron energy spectrum.

25
The track-etch monitor evaluated was an externally-powered device

designed to record the neutron flux from operating reactors and similar sources for extended periods of time. A strip of 35 mm wide polymer tape is drawn past a group of fissionable deposits which have been exposed to the local neutron flux.

A fraction of the fission fragments generated penetrate the tape producing radiationdamaged tracks that are subsequently etched and counted to permit a reconstruction of

the temporal flux history to which the monitor was exposed. Each monitor is equipped

with sufficient tape to cover a year of reactor operation time. The monitor is

designed to operate at a neutron flux of 10® ncm ^s

In one of the actual field tests, a monitor was installed above

the shroud at the Maine Yankee Power Reactor in Wiscassett, Maine, for ten

months. During this period of time, the 855 Megawatt reactor underwent four

unscheduled shut-downs and over eight changes in reactor power-levels. The

14.5 meter tape was removed from the monitor, chemically etched to reveal the

fission tracks, which were measured. The investigation of the tape indicated

that the monitor was able to record the changes in reactor power but had suffered several mechanical malfunctions, and furthermore was location-dependent

for optimum neutron flux measurement. A second monitor was placed in the

Wisconsin Public Service Corporation's Kewaunee Nuclear Power Plant for a shorter period of time, and similar information was obtained.

The final conclusion reported to the IAEA was that the monitor

would technically perform the functions that were required of it; however, it

would not be completely reliable due to frequent mechanical failure. The IAEA

was also advised that the only means to achieve the unattended monitoring

of power reactors was to completely redesign the motor-gear train assembly of

the monitor.

This work is being performed in the Center for Analytical Chemistry

under the sponsorship of the International Safeguards Project Office (ISPO) at the

Brookhaven National Laboratory.

B. Destructive Analytical Chemistry

The goal of the Destructive Analytical Chemistry Task is to provide

standardization for wet chemical and mass spectrometric methodology used for

the assay of nuclear materials. The research of this Task is divided into

three major components:

• Research to produce and certify Standard Reference Materials (SRMs)

• Support for Measurement Assurance Programs (MAPs)

• Chemical and isotopic measurements to support NDA

When requested, and as needed, assistance is provided to other domestic

laboratories in government and industry. Assistance is also provided to other

countries and to international and/or multinational organizations in the

accurate measurement of certified reference materials.

(1) Standard Reference Materials

The research, development and production necessary to certify and

distribute an NBS SRM generally requires the cooperative effort at NBS of

Program Offices, Centers and Divisions. In addition, there is usually a need

for support of materials fabricators and of other academic, government or

26
industrial laboratories. This approach is beneficial, cost effective and

conserves the limited resources available for standardization by utilizing

the best scientific talent available.

(a) ^**‘*Pu Spike SRM

Approximately 900 bottles containing 1 mg of ^**‘*Pu spike have

been prepared at Los Alamos Scientific Laboratory (LASL) . Measurements have

been made at NBS using isotope dilution mass spectrometry (IDMS) to determine

the isotopic composition and elemental concentration of this material. These

measurements and those made at New Brunswick Laboratory (NBL) by coulometry

and at LASL by coulometry and IDMS will be used to certify the ^‘***Pu as an NBS

Standard Reference Material. All measurements have been completed.

NBS analyzed seven ^‘***Pu samples. Each was spiked with one of

three SRM 949e (plutonium assay standard, 97.456% ^^^Pu) solutions prepared for

this spike calibration and equilibrated by reduction and oxidation of the mixed

solutions. This work was done by LASL and NBS personnel at LASL. Prior to mass spectrometric analysis at NBS, the samples were purified by ion exchange

chromatography to remove daughter products, primarily and ^**^Am, which

represent potential mass spectrometric isobaric interferences.

A pulse- counting detector was installed in a standard NBS-design

thermal ionization mass spectrometer, replacing the conventional Faraday cage

detector, in order to make high sensitivity measurements requiring only nanogram

quantities of plutonium per determination. Thus, the radiation hazard and

instrument contamination was reduced by greater than a factor of 1,000 relative

to the conventional triple-filament mass spectrometric procedure which requires

4 yg of sample per determination.

The pulse- counting measurement system consists of a 17-stage

electron multiplier of Swiss manufacture with the "Rajchman" structure and

Cu-Be conversion dynode, a high-speed non- overloading discriminator-amplifier,

and a high-speed commercial counter. The voltages to the dynodes of the

multiplier are fed off a high- impedance divider string external to the vacuum

and supplied by a commercial power supply. The theoretical deadtime of the

system as calibrated by a double-pulse generator with nanosecond pulse capabilities was verified by an empirical calibration utilizing the uranium isotopic SRMs

.

The mass spectrometric loading technique utilized was an electrodeposition process in which the plutonium is plated directly onto the sample

filament. Approximately 0.1 to 0.2 ng of Pu was plated onto the filament in a reproducible fashion as evidenced by the mass spectrometric behavior observed

throughout the analytical program. This amount was determined by high-efficiency

a- counting measurements made on representative filaments.

The correction factor for isotopic fractionation was determined

from the analysis of plutonium isotopic SRMs 947 and 948. Multiple determinations were made throughout the spike calibration program to guarantee control

of the measurement process and provide an indication of measurement precision.

The correction factor for fractionation determined from the ^"^^Pu/^^^Pu certified/

experimental values for the standards was applied to all experimental ratios. The

compositions of the SRM 949e spike material and ^'*‘*Pu material were determined by

duplicate mass spectrometric analyses of three samples of each material. Duplicate

determinations of the seven spiked ^‘***Pu samples were also made. A total of 54 mass spectrometric analyses were made using an estimated 5-10 ng of Pu. Conventional

procedures would have required 200 yg.

27
The grand average o£ all calculated concentrations (1.9948 ^

0.0012 yM/mL) indicates a precision in ratio measurement of ^ 0.1%, which is

consistent with precision of standards measurements and experimental ratios

.

The dominant error in this measurement procedure is due to the extrapolation

of the correction factor determined on the “Pu/ ^Pu ratio of the standards

to the ^**‘*Pu/^^^Pu ratio of the unknowns. This factor increases the confidence

limit for the result to 0.16%. The results of the collaborating laboratories are summarized in the following table.

Comparison of Results

^**^Pu Concentration

Lab Technique Samples Determinations Value Measured S.D.

NBS IDMS (^^^Pu Spike) 7 16 1.9947 +0.0012

NBL Coulometry 9 9 1.9941 +0.0004

LASL Coulometry 5 5 1.9944 +0.0015

IDMS (^‘‘^Pu Spike) 1 6 1.9925 1^0.0014

This work is being performed in the Center for Analytical Chemistry

under the sponsorship of DOE.

(b) Spike SRM

Approximately 400 ampoules of a spike, SRM 995, have been

prepared containing 5 mg U in 10 mL of HNO3 (1 + 19) . Before ampouling, the

uranium was purified by anion exchange chromatography to remove ^^^Th and other

daughter products.

The concentration of uranium in the ampoules of the SRM were determined by thermal ionization isotope dilution mass spectrometry following a sampling

plan supplied by the NBS Center for Applied Mathematics: eight ampoules were

chosen for use in the assay of the SRM. Separate aliquots from each of the

ampoules were spiked with known amounts of (SRM 993) and uranium metal

(SRM 960, assay standard). In addition, eight aliquots of SRM 993 were spiked

with SRM 960 as a cross check on the assay of these materials. Thus, all three

SRMs have been assayed against each other.

The statistical design of the experiment allowed for the assessment

of the following parameters: ampoule- to-ampoule variations among the samples,

sample-to-sample variations among the and natural uranium metal spikes,

inconsistency in the concentration previously assigned to the spike SRM, and

finally the measurement error in the concentration of the spike SRM. No

ampoule-to-ampoule or sample-to-sample variations were detected from the statistical

evaluation of the data. The concentration of spike (SRM 995) was found to be

489.93 yg U/g with an uncertainty at the 99% confidence interval of jjO.037%. This

uncertainty can be divided into a -^0.011% random error component and a -*^0.026%

possible systematic error. The isotopic composition of SRM 995 was also determined

mass spectrometrically using both Faraday cage and ion counting detection systems.

The content of the SRM was found to be 99.9245 -f 0.0006 atom percent.

This work is being performed in the Center for Analytical Chemistry

under the sponsorship of NRC, with statistical help from the Center for Applied

Mathematics

.

28
(2) Methodology for Chemical Assay of Nuclear Materials

High-precision and high-accuracy chemical assay techniques are essential

if there is to be adequate safeguarding of the nuclear materials in the fuel cycle.

These techniques, in conjunction with well characterized SRMs, help provide a sound

base for materials measurement and accountability. Chemical assay procedures are also essential to the preparation of high-accuracy primary reference materials of

known isotopic composition for mass spectrometer calibration.

(a) Moisture in PuOa

The experimental phase of this Sub-Task was completed on schedule

in this fiscal year, culminating the work on moisture in plutonium dioxide (PuOa)

.

An investigation was made of vessels, lids and septa for relatively

short-term storage of methanol containing water extracted from metal oxides or other materials; storage prior to titration of the methanol -water mixture is con- venient. The two systems of most promise are the Reacti-Vial System* consisting

of borosilicate glass vials (5 mL capacity) or flasks (10 or 25 mL capacity) and

Teflon vial closures with Mininert* valves; and Vacutainers* (10 mL capacity),

partially evacuated test tubes with rubber stoppers. The Reacti-Vial System is

satisfactory, but care must be taken to leak-test the valve. The most satisfactory

of the Vacutainers investigated is the Becton-Dickenson* No. 6440, with uncoated

inner surface and glycerine- lubricated pink rubber stopper. The Vacutainer

does contribute water vapor from the head space; the contribution of water

from the pink stopper is much less than that from the red stopper in more

recent use.

The paper, "Telescopic Viewer in Syringe Calibration", appeared

in the February 1980 issue of Analytical Chemistry. A manuscript, "Calculation

of Solvent-Water Mixture Volumes", has been accepted for publication in Analytical

Chemistry. The manuscript presents a procedure which enables calculation of the

ratio of the volume of a solvent-water mixture to the sum of the volumes the

components would occupy separately; expressions have been derived for the general

case and have been applied to the determination of water by Karl Fischer titration

of water extracted from various substances into methanol which is then introduced

into a titration vessel volumetrically

.

A manuscript, "Buoyancy Correction and Weighing on Analytical

Balances", by R.M. Schoonover and F.E. Jones, has been submitted to Analytical

Chemistry. This manuscript treats, in detail, buoyancy corrections to be

applied to weighing on analytical balances. These corrections are applicable

to the several weighings involved in the Karl Fischer titration determination of

moisture in PuOa.

A manuscript reviewing the moisture in PuOa problem and discussing

moisture determination methods is in preparation.

*Certain commercial equipment, instruments, or materials are identified in

this paper in order to adequately specify the experimental procedure. In no

case does such identification imply recommendation or endorsement by the National

Bureau of Standards, nor does it imply that the material or equipment identified

is necessarily the best available for the purpose.

29
A visit was made to the Monsanto Mound Laboratories at Miamisburg,

Ohio, to discuss the possibility of making moisture measurements (by Karl Fischer

titration) on PuOa at Mound. The suggestion was very well received by Mound

personnel, and there appeared to be no insurmountable technical problems. Contacts

were then made to acquire PuOa on which to make the measurements. It was decided

that the better course of action would be to make the measurements at a facility

which had proximate access to an excellent source of supply of several different

batches of PUO2 . Consequently, a visit was made to the Hanford Engineering

Development Laboratories (HEDL) operated for DOE by the Westinghouse Hanford

Company at Richland, Washington, to arrange to acquire several samples of PuOa

from the Rockwell Hanford Operations, and to make the measurements at HEDL. In

preparation for the measurements, Karl Fischer titration apparatus was modified

for use in a glovebox and other accessory equipment was acquired.

Measurements of the moisture content of PuOa were made by Karl

Fischer titration on three 15-gram samples from three different suppliers:

Rockwell Hanford Operations (RHO) (sample designated Pu 113) ; the Savannah

River Plant (Pu 124) ; and Los Alamos Scientific Laboratories (Pu 135) . The

moisture content of 200-milligram samples of the same oxide was determined using

a Model 902H Moisture Evolution Analyzer operated at 400 ®C. The Karl Fischer

work in the glovebox and the Moisture Evolution Analyzer work were done by a HEDL technician. Each of the 15-gram samples was milled for 15 minutes in 25

milliliters of methyl alcohol in a Spex Mixer/Mill vial containing three tungsten

carbide pellets supplied by RHO. As a blank, 25 milliliters of methyl alcohol was similarly milled. A methyl alcohol-water mixture prepared at NBS and injected

into Vacutainers was used to standardize the titrator. The Karl Fischer (KF)

titration measurements were carried out very successfully; the mean values of the

moisture content and the corresponding relative standard deviation of the mean

are shown in the table below. The values determined using the Moisture Evolution

Analyzer (single observations) are also shown in the table. Since the MEA result

for Pu 113 was much lower than the Karl Fischer result, HEDL subsequently made MEA

measurements on two samples taken from different places in the can; the results

were 0.0735% and 0.0750%. Since the KF and MEA results on Pu 124 and Pu 135 were

in satisfactory agreement, it is apparent that the milling and extraction in

methyl alcohol removed more moisture from Pu 113 than did the oven at 400 ®C in

the MEA. The results of the KF measurements will be presented at the January 1981

meeting of ASTM Committee C26 at Ft. Myers, Florida, with the ultimate intent of

having the KF procedure included in an existing ASTM Standard.

Measurements of the Moisture Content of PuOa

KF Titration Moisture Evolution Analyzer

Pu 113

Pu 124

Pu 135

Mean Value of

Moisture Content (%)

0.3008

0.7490

0.4702

Standard Deviation

of Mean

0.0043

0.0078

0.030

Mean Value of

Moisture Content (%)

0.0857

0.704

0.500

This work is being performed in the Center for Mechanical Engineering

and Process Technology under the sponsorship of DOE.

30
(b) Resin Beads

High sensitivity isotopic measurements of uranium and plutonium

by thermal ionization mass spectrometry using an anion resin bead as the emitter

has been investigated. The use of the resin bead has been studied for its

promising advantages in facilitating shipping, minimizing sample size, and

sample handling in the isotopic analysis of uranium (U) and plutonium (Pu) for

required nuclear safeguard measurements. Some of the specific advantages of

the resin bead technique result from (1) the selective absorption by the beads

of U and Pu from the fission and actinide produces in dissolver solutions, (2) the

ability to load and analyze beads directly in the mass spectrometer, and (3) high

ion yield from the bead matrix which markedly reduces the requires sample size and

thus the potential radiation hazard.

The NBS effort in the U and Pu isotopic analysis program has been

directed at the critical evaluation of the resin bead technique with respect to

achievable precision and accuracy. Factors which affect this are ionization

efficiency, ion beam stability, fractionation control, and isobaric interferences.

The parameters associated with the loading of U on resin beads have been investigated for the purpose of producing reference bead materials. The loading procedure

has a demonstrated affect on loading efficiency (amount of U per bead divided by

the total bead capacity) and ionization efficiency, parameters which critically

affect mass spectrometric reproducibility and precision. These investigations

have required the development of individual bead assay procedures, batch assay

procedures, and extensive mass spectrometric investigations.

As a part of the NBS effort, a round robin has been organized to

introduce laboratories which have the capability of making high sensitivity mea- surements to the resin bead technique and to receive, in turn, an indication of

measurement state-of-the-art as related to U and Pu resin bead analysis. The

response to requested participation in the round robin was excellent, and 12

laboratories agreed to participate. The laboratories have been sent the first

set of samples and partial results have been received. These first samples

contained U at the 30 ng and 300 ng levels. The second samples will contain U

at the 2 ng level and the third set of samples will contain Pu at the 2 ng level.

A fourth set of samples containing both U and Pu at the ng level is planned.

The resin bead program has been operated in close contact with

Oak Ridge National Laboratory (ORNL) , which is the principle promoter and active

user of the technique. A set of resin beads containing both U and Pu were

prepared at ORNL and independently analyzed by both ORNL and NBS. These beads

contained material representative of 30,000 megawatt-days burn-up from a LWR and

had been spiked with ^**^Pu and for isotope dilution analysis. A set of the

beads has been forwarded to the IAEA in Zeibersdorf, Austria, for calibration and

standardization of their instrumentation.

Analysis of this mixed uranium/plutonium bead material has

demonstrated that to reproduce isotopic fractionation, the variability of

which limits measurement precision and accuracy, requires careful control of

the time and temperature program of the mass spectrometric procedure. Although

this statement is generally true for all thermal ionization measurements, the

fact that two elements, both at the nanogram level and both with five isotopes, are measured from a single sample makes control of isotopic fractionation more

critical and more difficult. The mass spectrometric procedure used must also

allow correction for the mutual ^^®Pu and isobaric interferences. Initial

31
attempts to bum-off Pu quickly prior to the U measurements required too hot a temperature which resulted in severe uranium isotopic fractionation. Subsequently, a procedure was followed that utilized a lower temperature and slower

rate of Pu burn-offs, and, although necessitating a correction of a few percent

for the ^^®Pu in the signal, resulted in much less severe and much more reproducible uranium isotopic fractionation. The measurement precisions for

the ^“^^Pu/^^^Pu and the 2 33^^2 3 8^ ratios of this material were 0.15% and 0.10%,

respectively (la) .

This work is being performed in the Center for Analytical Chemistry

under the sponsorship of DOE and ISPO.

(3) Investigations of Sample-Mounting Techniques for Uranium Isotopic

Analysis by Thermal Ionization Mass Spectrometry

The accuracy and precision of mass spectrometric isotope ratio measurements is limited by the ability to control isotopic fractionation during the

ionization process. This mass -dependent fractionation appears to be dependent

on the molecular species being volatilized from the sample filaments. In the

case of uranium, the per mass fractionation correction (ratio of true ratio to

measured ratio) can be altered by as much as 0.1% depending on the conditions

under which the uranium nitrate solution is dried on the sample filaments prior

to insertion into the mass spectrometer.

The effects of static and dynamic air flow environments have been

investigated, along with different drying temperatures which produce different

uranium oxides on the filaments. Microscopic examination of the filaments

during sample drying has revealed that the filament temperature at which con- version to the various oxides occurs is not reproducible and that in some cases

the oxide form changes during the few minutes between completion of the sample

mounting and insertion into the mass spectrometer. These observations have

resulted in the development of a drying technique which keeps the drying temperature low to prevent oxide formation. This technique has been successfully

applied to the assay of the spike SRM and has demonstrated the capability

of accuracies and precisions of better than 0.05%.

Additional studies directed toward the identification and control of

the chemical species formed on the mass spectrometer filaments is continuing

with the eventual goal of achieving routine precisions of 0.01% for uranium

isotopic measurements.

This work is being performed in the Center for Analytical Chemistry

under the sponsorship of NRC and DOE.

C. Bulk Measurements

The Bulk Measurements Task occupies a position of strategic importance in

both the NBS Nuclear Safeguards Program and in nuclear safeguards in general.

The activities of the Task involve the determination of the quantity of nuclear

material in specific areas and processes in a nuclear fuel cycle plant and

between specific areas and processes. Measurements of mass, volume, density,

flow, pressure and temperature contribute to the determination of the quantity

of nuclear material; the measurements of these physical variables interact with

each other and with the activities of the other three Tasks in the NBS Nuclear

Safeguards Program.

32 1
(1) Flow

A system has been designed and constructed for checking the calibration

of the NBS laser Doppler velocimeter (LDV) system. The LDV system measures fluid

velocity inside our 5 cm diameter by 60 cm long glass test section. The calibration check is necessary because when the laser beam passes through the curved

glass, the beam is bent in a way that is difficult to describe theoretically

and with sufficient accuracy. This is true even though the round glass tube is

totally immersed in water contained within flat glass windows. The calibration

system uses a wire traveling longitudinally through the pipe at a known constant

velocity. The wire can be moved to any location in the pipe cross section by two

stepping motors interfaced to the same computer that operates the LDV system.

Figure 8 shows the measured fringe spacing as a function of the wire

position across the beam waist. The spacing is constant to within a fraction

of a percent for both the green and blue beams. Figure 9 shows that the measured

fringe spacing at various locations in the pipe volume is constant to within a fraction of a percent. As demonstrated by the data, the calibration of the LDV

system has been completed successfully.

Work on the correlation flow meter has progressed from the preliminary

version used to measure the velocity of bubbles in water flowing in a pipe to a more sensitive and noise-free system which is under construction at present. The

sensing electrode consists of a wire offset from the ground plane and facing an electrically active plate located across a 3/4" glass tube. The wire and the

active plate form a capacitor which, together with a balancing capacitor, are connected to the input of a tuned amplifier. The capacitive bridge was balanced

to about 50 yV out of 10 V at a frequency of 1 MHz. The output of the tuned

amplifier was fed into a phase sensitive detector (PSD) operating at 1 MHz. Due

to the sensitivity of the above detector it was found that the output of the PSD

changed over a period of minutes. This variation was traced to changes in the

properties of the flowing tap water, for example, its bubble content. To eliminate

the slow variation, a design of a computer based feedback circuit was initiated.

The feedback circuit samples the integrated output of the PSD and adjusts the

values of two photoresistors located in the bridge circuit in order to minimize

the PSD signal.

This work is being performed by the Continuous Process Technology

Program under the sponsorship of DOE.

(2) UFe Mass Measurement Implementation Program

The objective of this Sub-Task is the improvement of in-facility

weighing of large UFe cylinders. The effort involves the implementation of

a Measurement Assurance Program (MAP) for the measurement of the mass of UFe

cylinders, filled with UFe oi" empty. The MAP provides continually verifiable

evidence of performance of the mass measurement process, giving timely and

quantitative uncertainty statements for the mass measurements.

A draft standard operating procedure was sent to participating

organizations for comment.

The 306 Replica Mass Standard (RMS), with mass determined by NBS, was first shipped to Oak Ridge to be used in calibrating the Oak Ridge In-House

Standards . The RMS clyinder was then shipped from Oak Ridge to the General

33
Electric Co. (G.E.) Facility at Wilmington, NC, where it was used to recalibrate

the G.E. In-House Standards, and then on to the Combustion Engineering Co.

facility at Hematite, MO, where they were used to calibrate In-House Standards.

This work is being performed in the Continuous Process Technology

Center and the Center for Applied Mathematics, under the sponsorship of NRC.

34
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D. Applied Mathematics

The applied mathematics effort in support of safeguards consists not only

of independent efforts, but also of collaborative efforts with other scientists

at NBS. (1)

Some Effective Statistical Approaches for Presenting Interlaboratory

NDA Enrichment Measurements . In order to realistically evaluate measurements on prototype and primary reference materials measured by several different nondestructive

assay (NDA) labs, it is necessary to distinguish real differences between

laboratory findings and artificial differences such as those caused by artifacts

of individual peak area calculations. This report provides guidance for locating

and assessing the magnitude of these peak area artifacts. In particular, it provides a variety of algorithms for linear peak area computations which make the

standards appear either most or least homogeneous, under a variety of statistical

criteria. The criteria include the usual F statistic as well as the standardized

range.

(2) Robust Inference for Items Measured a Few Times . Estimation methods

that de-emphasize the measurements that appear to be most in error offer the possibility of improved performance. This possibility, which occurs when the measurement error is non-Gaussian, is explored for some measurement designs not covered

by previous work on robust methods. In these designs, each item in a collection

of somewhat dissimilar items is to be measured two or three times, and the total

for the entire collection is to be estimated. The methods are based on the

assumption that the measurement errors for different items are from the same population. A method is proposed for each of three cases: three replicate

measurements on each item, two replicate measurements by one method and one measurement by another method on each item, and two replicate measurements on

each item. All the methods use the differences between the measurements on the same item to obtain a scale estimate by which the sizes of the measurement errors

are judged. How the methods adjust the measurements differs from case to case. When there are three measurements per item, the most dissimilar of the three is

downweighted. When there are only two measurements per item, the measurements

for the entire collection are used to judge which measurements to downweight.

The methods include estimates of the uncertainty due to measurement error, which

are also obtained from the differences between the measurements on the same item.

(3) Inventory Difference Calculations: Problems and Possibilities

(preliminary abstract of report in preparation) . The origin, development, and

termination of the "error study" task funded by the Nuclear Regulatory Commission

at the National Bureau of Standards is presented in this report.

Other reports which grew (at least partially) out of this study are listed and related to the intent of this study.

A general approach to the calculation of Inventory Difference (ID) and

its Limit of Error (LEID) was devised and refined through visits to a selected fuelfabrication facility. Hiis approach is discussed, with emphasis on the importance

of having measurements "under control" and on the possibility of automating the

computations. The concepts of "measurement process" and "Measurement Assurance

Program" are also discussed and their importance shown. Possible problem areas,

both those observed at the studied facility and others, are given, along with

possible directions for resolution.

37
'

Finally, new approaches to the calculation of ID and LEID being

developed elsewhere are described and their relation to the approach being

considered herein elucidated.

All of the statistical work is being done in the Center for Applied

Mathematics with the support of NRC and DOE.

E. Safeguards Systems Studies

The objective of Safeguards Systems Studies is to provide technical support

to the safeguards program of the DOE Office of Safeguards and Security (DOE/SS)

and the U.S. Initiative Program for international safeguards. Systems analysis

studies are performed leading to a more effective utilization of data and information from all sources for achieving safeguards goals. Program efforts contribute

sound technical input for design, development and operation of DOE/SS and domestic

nuclear plant programs that will be effective in protecting against covert diversion of special nuclear materials (SNM) by persons authorized access to the

material or international programs aimed at detecting diversion by the State.

Task activities addressed completion of the Concepts for Safeguards Information

j Systems study, modification of Diversion Path Analysis Computer Program 2, and

j adaptation of Diversion Path Analysis concepts to evaluation of international

safeguards as applied by the International Atomic Energy Agency.

(1) Concepts for Safeguards Information Systems

Concepts for Safeguards Information Systems (CSIS) are based on the

theory that meaningful safeguards decisions can only be formulated through

effective use of information from all pertinent sources, both within and, when

appropriate, from outside of DOE. Examination of DOE facilities, operations

offices and headquarters safeguards activities, coupled with the information

flowing in the present system, served as the basis of the safeguards information

system framework defined in CSIS. CSIS is generic in nature and, in this context,

the framework is defined by a heirarchy of decision makers whose safeguards

responsibilities and tasks are specified. Based on these specifications, the

information needs of each decision maker were developed and aligned with the

information generated, records maintained and interactions between decision

makers throughout the heirarchy. The application of CSIS will provide a check

of completeness of information flow and content of flow between decision makers

and serve primarily as a guide for designing, upgrading and implementing a sitespecific information system for safeguards.

Development of the concepts and framework for the generic safeguards

information system were completed and the draft document describing CSIS was submitted to DOE/SS.

(2) Diversion Path Analysis

Diversion Path Analysis (DPA) is a safeguards evaluation tool that can |

be used to determine the vulnerability of domestic material control and material

|

accounting (MC^MA) subsystems of safeguards to the threat of theft of SNM by a j knowledgeable insider. DPA specifically addresses diversion of SNM from its author-|

ized location within a domestic plant by a person who has access to the process areal

and/or the material. It is used to evaluate the ability of the MC^MA subsystems to

detect the loss of a fraction of the amount of SNM needed to construct a clandestine

nuclear explosive. Using the methodology, facility personnel systematically determin

(1) how, from the diverter's viewpoint, to covertly acquire SNM and conceal the theft

from the MC^MA subsystems; (2) how soon the MC5MA subsystems would indicate the theft

38
and (3) what modifications to the plant's safeguards system would be necessary

to eliminate, or reduce the severity of, the identified vulnerabilities.

DPAs completed during the last year by contractor personnel at Idaho

and Savannah River were assessed by NBS at the request of the Directors of

Safeguards and Security for the respective DOE Operations Offices. The Savannah

River personnel developed a Diversion Vulnerability Index while performing the

analyses at that site. This Index represents a crude cost-benefit measure and

assisted contractor management in selecting modifications for implementation.

Because of its potential usefulness at other sites, DPA Computer Program 2,

which assists in assembling modification data, was revised to include computation

of the Index.

(3) International Safeguards

In recent years, the International Atomic Energy Agency (IAEA) Board

of Governors has requested the IAEA Secretariat to increase the extent to which

the effectiveness of IAEA safeguards is gauged by objective analysis. A method

has been proposed, which is an adaptation of Diversion Path Analysis, to increase

both the uniformity and objectivity of effectiveness evaluation analyses. Development of the method represents a cooperative effort being performed under the U.S.

Initiative Program. The method is intended to direct, with minor variations, three

distinct modes of application. First, it can be used to guide generation of the

model safeguards approach and associated design assessment of a generic facility

type. Second, it can be used to develop the facility safeguards approach, for a specific facility that resembles the generic facility, and derive the implementation assessment for that approach. Third, it can be employed to carry out the

performance evaluation of an IAEA safeguards inspection of the facility based on the facility safeguards approach developed during the second mode of application.

A draft set of instructions and guidelines was developed for conducting

the first mode of application. This draft is currently undergoing revision based

on experience gained in developing case studies for two types of generic facilities.

The implementation experience has indicated, however, that the guidance provided for

this phase of the analysis is both practical and credible.

F. Users Guide, Safeguards Accountability Instrumentation and Techniques

The primary objective of the Users Guide is to provide specific recommendations on how facilities should be designed to accommodate the necessary measurements to meet the SNM accountability goals of the safeguards program. The Guide

will discuss how the measurement instruments and accountability systems should be

installed and will outline the supporting services required. The Guide will also

discuss facility design considerations so that the instruments can be efficiently

calibrated, operated and repaired, either manually or remotely.

The preliminary draft of the Guide, which was completed during the previous

fiscal year, was revised to reflect certain directives from the NRG. Discussions

were held with the persons at Mound Laboratories who are preparing a Handbook of

Nuclear Safeguards Measurement Methods . The purpose of these discussions was to assure that the two documents would be complementary.

The first rough draft of the Guide was completed and copies sent to contributors for comment and/or correction. In its draft form, the document had a length

of approximately 18,000 words.

After the cut-off date for comments. May 30, 1980, the Guide was rewritten

into its final form. It is now undergoing editorial review.

39
4. Measurements and Standards for Nuclear Waste Management - A Technical

Overview

The Program of Measurements and Standards for Nuclear Waste Management was established late in fiscal year 1980, after an extensive study of the materials

and measurements problems involved in nuclear waste management. As a result,

most of the efforts expended have focused on program startup. However, technical

progress has been made in specific areas.

The technical plans for the Nuclear Waste Program are divided into the

following areas: (1) Waste Forms Teachability Mechanisms; (2) Waste Forms

Research, Reference Materials Data and Measurement Methods; and (3) Containers,

Backfill and Math Support.

A. Waste Forms - Teachability Mechanisms

This task will review existing efforts by others, as well as carry out

experiments in selected areas at NBS to improve and understand the mechanisms

involved in leaching of radioactive waste species from an immobilizing matrix.

In order to accomplish this, the role or effect of radiation, mechanical properties, microstructure, microchemistry, thermodynamics, transport mechanisms,

thermochemistry, and various other disruptive processes will be investigated.

Planned activities for fiscal year 1981 include the completion of a set of

Monte Carlo calculations to analyze the energy deposition processes in the waste

matrix, evaluation of existing models of mass transport in solids for their applicability to the nuclear waste problem, and institution of experimental studies

concerning the structural stability and transport properties of crystalline

material containing large ratios.

B. Waste Forms - Research, Reference Materials Data and Measurement Methods

This task includes the development and dissemination of generic research

materials with well-characterized elemental composition to aid in the development

and promulgation of leach tests. Materials (glass) with varying leach rates

containing non-radioactive cesium, strontium, etc., will be provided.

Current activities include advising the Materials Characterization Center

(MCC) on the MCC-1 leach test and round robin, and providing a borosilicate glass

for use in that round robin. Development of a set of generic reference leach tests

in cooperation with Battelle’s MCC is a long range goal. During FY 1981 NBS will

develop the capability to perform several of the proposed reference leach tests

and, if required, suggest changes to the procedures to improve precision.

In addition to the above work, a literature survey is planned to compile,

evaluate, and publish a compendium of standard reference data on phase equilibria

of materials used for nuclear waste encapsulation. This will be done through the

existing mechanisms used to publish "Phase Diagrams for Ceramists", co-sponsored

by NBS and the American Ceramic Society. The compendium will include critically

evaluated phase diagrams which are one of the components needed for waste form

processing and for characterizing the compatibility and interaction of the waste

form with the geologic environment.

40
During fiscal year 1981, a comprehensive literature survey of all existing

published (archival) literature, including the first five volumes of "Phase

Diagrams for Ceramists", will be undertaken.

C. Containers, Backfill and Mathematical Support

This task is focused on the container and backfill material and includes

also the statistical and quality control effort for the whole program.

In the area of containers, existing efforts to understand corrosion

mechanisms will be reviewed, and specific research will be carried out in selected

areas to improve the understanding of degradation mechanisms of candidate materials,

particularly as they apply to long-term prediction and accelerated testing.

During fiscal year 1981, existing data and literature will be reviewed on possible canister degradation mechanisms and test methods, and state-of-the-art

information will be assembled for publication.

In order to provide well-characterized materials for use in NBS tests and

materials research by other laboratories, a complete stock of analyzed research

alloys will be developed during the coming year.

Also planned is a cooperative effort with the MCC in surveying and evaluating

existing data on underground corrosion of potential canister materials. A bibliography of existing data and literature on corrosion of alloys underground should

be completed.

Work on the backfill effort for the Nuclear Waste Program includes a review

of existing efforts elsewhere, as well as performing selected research at NBS to

improve the understanding of the basic functional mechanisms (excluding sorption

coefficient) related to emplacement of backfill materials. The information

obtained will be disseminated via publications and will provide support to other

NBS efforts. In addition, a workshop on backfills is being planned for

September 1981.

In order to promote compatibility of testing, the development and dissemination of research materials is planned. Possible candidate materials include

common clays such as illite, kaolinite, and montmoril Unite, as well as zeolites

and sand-bentonite mixtures. These materials will be evaluated and characterized

for homogeneity, elemental composition, structure, physical size, loss of weight

on drying, and stability in packaging.

Extensive use of statistical services available at NBS is planned for the

effective use of the interlaboratory testing required in the performance of these

tasks

.

41
5 . Appendix

A. NBS Seminars on Measurements for Nuclear Technology

NBS Nuclear Safeguards Seminar, ’’Safeguards Non-Destructive Assay Program”,

by Walter G. Martin, U.S. Nuclear Regulatory Commission, February 21, 1980.

NBS Nuclear Safeguards Seminar, ’’Measurements for Nuclear Materials

Safeguards - Their Development, Calibration, and Evaluation”, by Carleton Bingham,

Director, New Brunswick Laboratory, March 6, 1980.

NBS Nuclear Safeguards Seminar, ’’Overview of International Nuclear Safeguards”, by William M. Murphey, Arms Control and Disarmament Agency, April 25,

1980.

B. Committee Participation and Consulting Activities

(1) Committee Participation

James W. Behrens - Member, DOE Cross Section Evaluation Working Group

(CSEWG) , Standards Subcommittee; Member, Safeguards Committee, Institute for

Nuclear Materials Management

Charles D. Bowman - Member, Department of Energy (DOE) Nuclear Data

Committee

Stephen M. Baloga - Member, Technical Program Committee for American

Nuclear Society Topical Conference, ’’Measurement Technology for Safeguards and

Materials Control”, Kiawah Island, SC, November 26-30, 1979

B. Stephen Carpenter - Board of Directors, American Nuclear Society;

Member, Isotope and Radiations Division, Technical Committee for Nuclear Safeguards;

Member, Institute of Nuclear Materials Management Subcommittee INMM-9.3 on Nondestructive Assay of Standards Committee N15 on Methods of Nuclear Material

Control; Member, Department of Energy, Office of Safeguards and Security, Ad Hoc

Task Group on Measurements and Standards

Randall S. Caswell - Member, International Society of Radiology,

International Commission on Radiation Units and Measurement

Allan D. Carlson - Member, DOE Cross Section Evaluation Working Group

(CSEWG) , Standards Subcommittee

David A. Ditmars - Member, INMM 8.4, ’’Calibration Techniques in the

Calorimetric Assay of Pu-Bearing Solids”; Member, NBS Pu Steering Committee

James A. Grundl - Member, ASTM E10.05, Committee on Neutron Dosimetry

J.M. Robin Hutchinson - Chairman, International Committee of Radionuclide

Metrology (ICRM), Subcommittee on Low-Level Techniques Group; Member, American

National Standards Institute (ANSI) Committee on Nuclear Instruments and

Detectors; Secretary, ANSI Subcommittee N42.2 on Procedural Standards for

Calibration of Detectors for Radioactive Measurements

Harry H. Ku - serves on the Steering Committee of the Safeguards

Analytical Laboratory Evaluation Program

42
James A. Lechner - Member of American Society for Testing and Materials

(ASTM) Committee C26 on Nuclear Fuel Cycle; Member of ASTM Committee N15; advising

the Institute for Nuclear Materials Management Committee 9.4 on revised standard

for measurement control of NDA processes

Lawrence A. Machlan - Member, Plutonium Steering Committee at NBS;

Member, ASTM C26 (Nuclear Fuel Cycle)

43
William P. Reed - Member, ASTM C26, "Nuclear Fuel Cycle"; Member, ANSI

N15.9, "Nondestructive Assay"

Paul E. Pontius - Member, INMM8.1 Subcommittee on Mass Calibration

Techniques for Nuclear Material Control; Member, INMM8.2 Subcommittee on Volume

Calibration for Nuclear Material Safeguards

James R. Whetstone - Member, INMM8.2 Subcommittee on Volume Calibration

for Nuclear Material Safeguards

(2) Consulting Activities

Stephen M. Baloga and John C. Schleter - Consultants to DOE Savannah

River Operations Office during assessment of Diversion Path Analyses for Savannah

River Plant facilities; Consultants to DOE Idaho Operations Office during assess- ment of Diversion Path Analyses for Idaho National Engineering Laboratory facilities

Stephen M. Baloga - Consultant to DOE Savannah River Operations Office on statistical sampling plans and nuclear material measurements for inventory

verification

Charles D. Bowman - Performed a neutron dosimetry review for the Fusion

Materials Irradiation Test Facility (FMIT) , Hanford Engineering Development

Laboratory; performed linac neutron measurements for Lawrence Livermore National

Laboratory, Physics Division; performed gamma ray laser research for Los Alamos

Scientific Laboratory, Physics Division

Ronald G. Johnson - Performed photonuclear research for Lawrence

Livermore National Laboratory

Paul E. Pontius - Consultant to LASL on Bulk Measurements

Roald A. Schrack - Performed measurements for international safeguards

on special nuclear material for International Safeguards Project Office

C. Publications (from October 1, 1979 to September 30, 1980)

Baloga, S. M., and Hakkila, E, A., "Measurement Trends for Future Safeguards Systems", LA-UR-80-1817, Los Alamos Scientific Laboratory, June 1980;

also. Nuclear Materials Management, Proceedings Issue, Vol. IX (in press).

Baumgarten, G. P., Brame, V., Cooper, D. G., and Robertson, B., "Automated Tank

Calibrator", in Measurement Technology for Safeguards and Material Control

(Proceedings of ANS Topical Meeting, Kiawah Island, SC, November 26-30, 1979)

,

NBS Special Publication 582, pp. 517-533 (1980).

Behrens, J. W. , Systematics of Fission Cross Sections in the MeV Range--

An Update, Trans. Am. Nucl. Soc. 34, 770 (1980).

Behrens, J. W. , Johnson, R. G., and Bowman, C. D., "Pin-Hole Camera Imaging

of Neutrons Using a Position-Sensitive Proportional Counter, Trans. Am. Nucl.

Soc. 663-664 (1980).

Behrens, J. W., Schrack, R. A., and Bowman, C. D., Resonance Neutron

Radiography Using a Position-Sensitive Proportional Counter, ANS Annual Meeting,

June 3-7, 1979, Trans. Am. Nucl. Soc. 12^, 207, 208 (1979).

44
Behrens, J. W., Schrack, R. A., Carlson, A. D., and Bowman, C. D.,

Resonance Neutron Radiography for Nondestructive Evaluation and Assay Applications, Proc. Int. Conf. on Nucl. Cross Sections for Tech., Univ. of Tenn.,

Knoxville, TN, Oct. 22-26, 1979.

Behrens, J. W., Schrack, R. A., and Bowman, C. D., Nondestructive

Examination of a Defective Silver Braze Using Resonance-Neutron Radiography,

Nucl. Tech. 78 (1980).

Bowman, C. D., and Schrack, R. A., Influence of Vibrations of Gas Molecules

on Neutron Reaction Cross Sections, Phys. Rev. C No. 1, 58-64 (Jan. 1980);

also. Proceedings of an Int. Conf. on Neutron Physics and Nuclear Data for

Reactors and Other Applied Purposes, held at Harwell, U.K., Sept. 25-29, 1978,

published by OECD Nuclear Energy Agency (1979), pp. 736-741.

Bowman, C. D., Efficient Neutron Production Using Low-Energy Electron Beams,

Nucl. Sci. Eng. 7£, 12-15 (1980).

Bowman, C. D., and Johnson, R. G., Reports to the DOE Nuclear Data Committee,

BNL-NCS-27800, D0E/NDC-19/U, NEANDC(US) -207/U, INDC(USA) -83/U, 112-126 (May 1980).

Canada, T. R. , and Carpenter, B. S., Editors, Proceedings of Measurement

Technology for Safeguards and Materials Control, NBS Special Publication 582 (1980)

Carpenter, B. S., Pilione, L. J., Schroder, I. G., Roe, J. W., and Sanatani, S

"Evaluation of Reactor Track-Etch Power Monitor", Proceedings of Measurement

Technology for Safeguards and Materials Control, NBS Special Publication 582,

p. 234 (1980).

Ditmars, D. A., Special Reference Material Report, GM-10, "Encapsulated

Plutonium Heat Source".

Fassett, J. D., Kelly, W. R., Machlan, L. A., and Moore, L. J., "Mass

Spectrometric Isotope Metrology of Uranium on Resin Beads", Radioelement Analysis,

Progress, and Problems, W. S. Lyon, Ed., pp. 357-364, Ann Arbor, Press 1980.

Garrett, D., and Chang, T., "Nuclear Safeguard Interrogation of Waste

Containers with Resonant Neutrons", Proc. 40th ASNT National Fall Conf., 1980,

Houston, TX.

Johnson, R. G., Behrens, J. W., and Bowman, C. D., Source Imaging for FMIT

Using a Neutron Pin-Hole Camera, Proc. Symp. on Neutron Cross Sections from

10-50 MeV, Brookhaven, NY, May 12, 1980.

Jones, F. E., Schoonover, R. M., and Houser, J. F., "In-Tank Measurement

of Solution Density", in Measurement Technology for Safeguards and Material

Control (Proceedings of ANS Topical Meeting, Kiawah Island, SC, November 26-30,

1979), NBS Special Publication 582, pp. 534-537 (1980).

Jones, F. E., Schoonover, R. M., and Houser, J. F., "In-Tank Measurement

of Solution Density", J. Res. Nat. Bur. Stand. (U.S.) 85 , No. 3, pp. 219-221 (1980)

Liggett, W., "Assession Errors Related to Characteristics of the Items

Measured", Nuclear Materials Mngmt. 9^, pp. 78-82 (1980).

45
Schrack, R. A., and Bowman, C. D. , Calculation and Measurement of Fission

and Delayed Neutron Yields in U 3 O and UO2 , Nucl. Sci. 5 Eng. 75, 275 (1980).

Schrack, R. A., and Bowman, C. D., Chemical Dependence of Uranium Fission,

Proc. of the Int. Conf. on Nucl. Cross Sections for Tech., Univ. of Tenn.

,

Knoxville, TN, Oct. 22-26, 1979.

Schrack, R. A., Behrens, J. W. , Bowman, C. D., and Carlson, A. D., Safeguards Reference Measurement System Utilizing Resonance Neutron Radiography,

Proc. of the Topical Conf. "Measurement Technology for Safeguards and Materials

Control", held on Kiawah Island, SC, Nov. 26-29, 1979.

D. Talks (from Oct. 1, 1979 to Sept. 30, 1980)

Baloga, S. M., "Statistical Problems Associated with the Verification of

Nuclear Material Inventories at DOE Facilities", NBS Statistical Engineering

Laboratory Seminar, March 11, 1980.

Baloga, S. M., "Measurement Trends for Future Safeguards Systems", INMM

21st Annual Meeting, Palm Beach, FL, June 30-July 2, 1980.

Baumgarten, G. P., Brame, V., Cooper, D. G., and Robertson, B., "Automated

Tank Calibrator", American Nuclear Society Topical Meeting, Measurement Technology for Safeguards and Material Control, November 26-30, 1979, Kiawah Island, SC.

Behrens, J. W. , "Non-Destructive Assay of Fresh Nuclear Fuel Using Resonance

Neutron Radiography", Rennselaer Polytechnic Institute, Troy, NY, March 3, 1980.

Bowman, C. D., "Molecular Binding Effects on Neutron Nuclear Cross Section",

Univ. of Missouri, Columbia, MO, Oct. 31, 1979; Univ. of Missouri, Rolla, MO,

Nov. 1, 1979; Washington University, Nov. 2, 1979.

Bowman, C. D., "Resonance Neutron Radiography", Atomic Energy Research

Establishment, Harwell, England, March 14, 1980.

Bowman, C. D., "White Source Use in a Neutron Standards Laboratory", IAEA

Consultants Meeting on Neutron Source Properties, Kossuth Lajon University,

Debrecen, Hungary, March 17, 1980.

Bowman, C. D., "Accelerator Source for Neutron Nuclear Data Measurements",

as chairman of the Accelerator Sources Working Group, IAEA Consultants Meeting

on Neutron Source Properties, March 17-21, 1980.

Bowman, C. D., "Neutron Standards Measurements and Related Physics Research",

American Physical Society Meeting, Washington, DC, April 30, 1980.

Bowman, C. D., "Neutron Source for 10-50 MeV Cross Sections", as chairman of

the Neutron Sources Working Group of the Conference on 10-50 MeV Cross Sections,

Brookhaven National Laboratory, May 19-21, 1980.

Bowman, C. D., "Neutron Powder Diffraction Measurements Using the NBS 100-MeV

Electron Linac", Lawrence Livermore National Laboratory, Livermore, CA, Sept. 15,

1980.

Bowman, C. D., "Efficient Neutron Production Using 12 MeV Electrons", Sixth

Conf. on the Application of Accelerators in Res. ^ Industry, Nov. 3, 1980, Denton, TX

46
Carpenter, B. S., "Evaluation of Reactor Track-Etch Power Monitor", American

Nuclear Society Topical Meeting, Measurement Technology for Safeguards and

Materials Control, November 26-30, 1979, Kiawah Island, SC.

Fassett, J. D., Kelly, W. R. , Machlan, L. A., and Moore, L. J., "Mass

Spectrometric Isotope Metrology of Uranium on Resin Beads", 23rd Conf. on Analyt. Chem. in Energy Tech., Gatlinburg, TN, Oct. 10, 1979.

Fassett, J. D., "Systematic Errors in Isotope Ratio Measurements Using

Thermal Ionization and Pulse Counting Detection", 28th Analytical Conference

on Mass Spectrometry and Allied Topics, New York City, NY, May 26, 1980.

Garner, E. L. , and Machlan, L. A., "Mass Spectrometric Measurements to

Determine the Half-Life of ^**^Pu", American Nuclear Society Topical Meeting,

Measurement Technology for Safeguards and Material Control, November 26-30,

1979, Kiawah Island, SC.

Garrett, D. , and Cheng, T. , "Nuclear Safeguard Interrogation of Waste

Containers with Resonant Neutrons", talk presented at the 40th ASNT National

Fall Conference on Quality Testing Show, 1980, Houston, TX.

Gramlich, J. W., "Sample Mounting Techniques for High Accuracy Uranium

Isotopic Analysis", 28th Annual Conference on Mass Spectrometry and Allied

Topics, New York, NY, May 27, 1980.

Jones, F. E., Schoonover, R. M. , and Houser, J. F., "In-Tank Measurement

of Solution Density", American Nuclear Society Topical Meeting, Measurement

Technology for Safeguards and Material Control, November 26-30, 1979, Kiawah

Island, SC.

Reed, W. P., "The Role of Standard Reference Materials in Achieving Measurement Traceability", American Nuclear Society Topical Meeting, Measurement Technology

for Safeguards and Material Control, November 26-30, 1979, Kiawah Island, SC.

Schleter, J. C., "Diversion Path Analysis", DOE/NRC R8D Exchange Seminar,

June 13, 1980.

Schrack, R. A., "Quantitative Isotope-Selective Assay Using Resonance

Neutron Radiography", University of Glasgow, Glasgow, Scotland, March 25, 1980.

Schrack, R. A., Behrens, J. W. , Johnson, R. G., and Bowman, C. D., "Resonance

Neutron Radiography Using an Electron Linac", Sixth Conference on the Application

of Accelerators in Research and Industry, Nov. 3, 1980, Denton, TX.

Yolken, H. T., "National and International System of Measurement Standards

for Nuclear Safeguards", U.S. DOE/ IAEA International Training Course on Nuclear

Materials Accountability and Control for Safeguards Purposes, Santa Fe, NM,

May 27-June 6, 1980.

E. Sponsored Symposia and Workshops

Measurement Technology for Safeguards and Materials Control (Kiawah

Island, SC), November 1979

47
F. Office of Measurements for Nuclear TechnologySafeguards Management Team*

David A. Ditmars (CTMS)

Adolphas K. Gaigalas (CPTP)

John W. Gramlich (GAG)

Nuclear Waste Management Team*

Thomas E. Gills (OSRM)

Wolfgang K. Haller (CMS)

Howard S. Kingston (CAC)

*Bench Scientists devoting part of

their time helping to manage the

program.

48
G. Functional Statements

NATIONAL MEASUREMENT LABORATORY

Provides the national system of physical and chemical and materials

measurement; coordinates the system with measurement systems of other nations,

and furnishes essential services leading to accurate and uniform physical and

chemical measurement throughout the Nation's scientific community, industry,

and commerce; conducts materials research leading to improved methods of

measurement, standards, and data on the properties of materials needed by

industry, commerce, educational institutions, and government; provides advisory

and research services to other government agencies; conducts physical and

chemical research; develops, produces, and distributes standard reference

materials; provides standard reference data; provides calibration services; and

collaborates with the Bureau's major organizational imits in carrying out its

responsibilities

OFFICE OF MEASUREMENTS FOR NUCLEAR TECHNOLOGY

Provides the Nation with needed measurement standards and services for

nuclear technology in the areas of nuclear waste management and safeguarding

nuclear materials; plans, directs, and coordinates the Program's laboratory

work that is carried out within NBS units; and disseminates these standards

and services domestically and to other nations and to international organizations.

49
H. NML Organizational Chart
I . NBS Organizational Chart

DIRECTOR

Deputy Director

ASSOCIATE DIRECTOR FOR

PROGRAMS, BUDGET A FINANCE

Program Office Budget Office Office of the Comptroller

Planning Office

NATIONAL ENGINEERING

LABORATORY

Center for Applied Mathematics

Canter for Electronics & Electrical Engineering Center for Mechanical Engineering &

Process Technology

Center for Building Technology

Center for Fire Research

Center for Consumer Product Technology

Center for Field Methods

OFFICE OF THE DIRECTOR

NBS/BOULDER LABORATORIES

DIRECTOR OF ADMINISTRATIVE &

INFORMATION SYSTEMS

Center for Information Systems

Center for Facilities Management

Public Information Division Personnel Division Management & Organization Division

NATIONAL MEASUREMENT

LABORATORY

Center for Absolute Physical Quantities Center for Radiation Research

Center for Thermodynamics & Molecular

Science

Center for Analytical Chemistry Center for Materials Science

INSTITUTE FOR COMPUTER

SCIENCES & TECHNOLOGY

Systems & Software Division Computer Systems Engineering Division

51
/ NBS«114A iREv. 2>eo) U.S, DEPT. OF COMM. 1. PUBLICATION OR 2. Performing Organ. Report NoJ 3. Publication Date BIBLIOGRAPHIC DATA

REPORT NO.

SHEET (See instructions) NBSIR 81-2205 NBSIR 81-2205 January 1981

4. TITLE AND SUBTITLE

Office of Measurements for Nuclear Technology 1980 Annual Report

5. AUTHOR(S)

H. Thomas Yolken, William P. Reed, and B. Stephen Carpenter

6. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions)

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

7. Contract/Grant No.

t. Type of Report & Period Covered

Office Annual Report

Fiscal Year 1980

9.

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State. ZIP)

NBS

10.

SUPPLEMENTARY NOTES

Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11.

ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bi bliography or literature survey, mention it here)

This annual report is a summary of the National Bureau of Standards (NBS)

Measurements for Nuclear Technology (MNT) Program for Fiscal Year 1980. The MNT

activities at NBS are divided into two programs: Nuclear Safeguards and Nuclear

Waste Management.

The MNT Program is one of several matrix managed efforts at NBS. The programs

provide a focus for the activity, both inside and outside NBS. The programs provide

funds and directions for needed technical work that is done within NBS Centers.

People remain attached to Centers but are funded for specific activities in a matrix

management approach. A program provides central organization for outside inquiries

and for distribution of results. Often programmatic focus can provide improved

assistance to outside agencies with measurement problems. The MNT Program is

operating in this manner.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolons)

accountability guide; bulk measurements; isotopic assay; leachability studies;

nondestructive assay; nuclear safeguards; nuclear waste management; Standard Reference

Materials; statistical evaluation

13. AVAILABILITY

Unlimited For Official Distribution. Do Not Release to NTIS

Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

[XJJOrder From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

56

15. Price

$ 8.00

USCOMM-OC e043-P80