NUREG/CR-5734

KIITP-415

Recommendations to the NRC on

Acceptable Standard Format and

Content for the Fundamental 

Nuclear Material Control (FNMC)

Plan Required for Low-Enriched

Uranium Enrichment Facilities

repared by

. W. Moran, W. L. Belew, G. A. Hammond, L. M. Brenner

)ak Ridge K-25 Site

I1st Century Industries, Inc.

Irepared for

J.S. Nuclear Regulatory Commission
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NUREG/CR-5734

K/ITP-415

Recommendations to the NRC on

Acceptable Standard Format and

Content for the Fundamental

Nuclear Material Control (FNMC)

Plan Required for Low-Enriched

Uranium Enrichment Facilities

Manuscript Completed: August 1991

Date Published: November 1991

Prepared by

B. W. Moran, W. L. Belew, Oak Ridge K-25 Site

G. A. Hammond, L. M. Brenner, 21st Century Industries, Inc.

Oak Ridge K-25 Site

Managed by Martin Marietta Energy Systems, Inc.

Oak Ridge K-25 Site

Oak Ridge, TN 37831

Subcontractor:

21st Century Industries, Inc.

P.O. Box 2636

Gaithersburg, MD 20886

Prepared for

Division of Safeguards and Transportation

Office of Nuclear Material Safety and Safeguards

U.S. Nuclear Regulatory Commission

Washington, DC 20555

NRC FIN L1300

Under Contract No. DE-AC05-840R21400
Abstract

A new section, 10 CFR 74.33, has been added to the

material control and accounting (MC&A)

requirements of 10 CFR Part 74. This new section

pertains to U.S. Nuclear Regulatory Commission

(NRC) -licensed uranium enrichment facilities that are

authorized to produce and to possess more than one

effective kilogram of special nuclear material (SNM)

of low strategic significance.

The new section is patterned after 10 CFR 74.31,

which pertains to NRC licensees (other than

production or utilization facilities licensed pursuant to

10 CFR Part 50 or Part 70 and waste disposal

facilities) that arc authorized to possess and use more

than one effective kilogram of unencapsulated SNM of

low strategic significance. Because enrichment

facilities have the potential capability of producing

SNM of moderate strategic significance and also

strategic SNM, certain performance objectives and

MC&A system capabilities are required in 10 CFR

74.33 that are not contained in 10 CFR 74.31.

This document recommends to the NRC information

that the licensee or applicant should provide in the

fundamental nuclear material control (FNMC) plan.

This document also describes methods that should be

acceptable for compliance with the general

performance objectives. While this document is

intended to cover various uranium enrichment

technologies, the primary focus at this time is gas

centrifuge and gaseous diffusion.

Mi NUREG/CR-5734
Contents

- - ~~~~~Page

Abstract .............................................. i

Acronyms ............................................... vii

Introduction ............................................. 1

Pcrformance Objectives and System Features and Capabilities ....................................... 3

Performance Objectives ............................................. 3

System Features and Capabilities . ............................................. 6

1 Organization ................................................ 9

1.1 Corporate Organization ....................... .................. ' 9

1.2 Plant or Site Organization ....................................... 9

1.3 MC&A Organization ....................................... 9

1.3.1 Responsibilities and Authority . ....................................... 9

1.3.2 MC&A Procedures ....................................... 10

1.4 Training and Qualification Requirements ........................................ 10

1.5 MC&A System Description ........................................ 10

2 Measurements ......................................... 11

2.1 M a u e e tPo nt ..................................................... . . . 11

2.1 Measurement Points ............... 11

2.2 Measurement Systems.-.11

2.2.1 Bulk Measurement Systems ............................ 11

2.2.2 Analytical Measurement Systems ............... 11

2.2.3 NDA Measurement Systems ............................ 11

2.2.4 Other Measurement Systems ............................ I 12

2.3 Measurement Unccrtainties ............................. 12

2.4 Measurement Procedures ............ ................ 12

3 Measurement Control Program ............................ 13

3.1 Organization and Management .. 13

3.1.1 Functional Relationships .. 13

3.1.2 Procedures .13

3.1.3 Contractor Program Audits and Reviews .13

3.2 Calibrations .................. 13

3.3 Control Standard Program .................... '.'.'.'.'.14

3.4 Replicate Program ............. . ' 15

3.5 Control Limits .. 16

3.5.1 Measurement Control Data Analysis ................................. 16

3.5.2 Response Actions.......... .......... . 16

4 Statistics ...... 17

4.1 Determination of Measurement Uncertainties ...................................... 17

4.2 Determination of SEID ...................................... 17

v NUREG/CR-5734
Page

5 Physical Inventories . .................................................................. 19

5.1 General Description ........................................................... 19

5.2 Organization, Procedures, and Schedules ............................................ 19

5.3 Typical Inventory Composition ................................................... 19

5.4 Conducting Dynamic Physical Inventories ........................................... 20

5.5 Conducting Static Physical Inventories .............................................. 20

5.6 Inventory Difference Limits and Response Actions .................................... 22

6 Item Control ......................................................................... 23

6.1 Organization ................................................................. 23

6.2 General Description ........................................................... 23

6.3 Item Identity Controls .......................................................... 23

6.4 Storage Controls .............................................................. 23

6.5 Item Monitoring Methodology and Procedures ....................................... 23

6.6 Description of Typical Item Strata ................................................. 24

6.7 Investigation and Resolution of Item Discrepancies .................................... 24

7 Shipper-Receiver Comparisons ............................ ............................... 25

7.1 Receiving Procedures .......................................................... 25

7.2 Determination of Receiver's Values ................................................ 25

7.3 Evaluation of Shipper-Receiver Differences .......................................... 25

7.4 Resolution of Significant Shipper-Receiver Differences ................................. 25

8 Assessment and Review of the Material Control and Accounting Program .......................... 27

8.1 General Description ........................................................... 27

8.2 Report of Findings and Recommendations .......................................... 27

8.3 Management Review and Response to Report Findings and Recommendations .... ........... 28

9 Program for Precluding and Dctecting Unauthorized Production of Enriched Uranium .... ............ 29

9.1 Organization ................................................................. 29

9.2 General Description of Program .................................................. 29

9.3 Data, Information, and Activities to be Monitored ..................................... 30

9.4 Reporting and Documentation Requirements ........................................ 31

10 Resolving Indications of Missing Uranium and of Unauthorized Production of Enriched Uranium .... ... 33

10.1 Methods and Procedures for Identifying Indicators ..................................... 33

10.2 System and Procedures for Investigating and Resolving Indicators ......................... 33

10.3 Response Actions for Unresolved Indicators ......................................... 34

10.4 Documentation Requirements .................................................... 35

11 Informational Aid for Assisting in the Investigation and Recovery of Missing Uranium or Assisting in the

Investigation of Unauthorized Enrichment ................................................. 37

12 Recordkeeping ...................................................................... 39

12.1 Description of Records .......................................................... 39

12.2 Program and Controls for Ensuring an Accurate and Reliable Record System .... ............ 39

Glossary . ............................................................................ 41

NUREG/CR-5734
Acronyms

Detection quantity

Detection thresfiold

Formula kilogram

Fundamental nuclear material control

High-enriched uranium

Item control arca

Inventory difference

Low-enriched uranium

Material balance area

Material control and accounting

Nondestructive assay

Nuclear Materials Management and

Safeguards System

U.S. Nuclear Regulatory Commission

RBIPI

SEID

SM

SNM

SRD

SwU

U

U-233

U-234

U-235

U-238

U3 08

UF 6

wt %

Running book in-process inventory

Standard error of the inventory difference

Source material

Special nuclear material

Shipper-receiver difference

Separative work unit

Uranium

Uranium-233

Uranium-234

Uranium-235

Uranium-238

Urano-uranic oxide

Uranium hexafluoride

Weight percent

NUREG/CR-5734

DQ

DT

FKG

FNMC

HEU

ICA

ID

LEU

MBA

MC&A

NDA

NMMSS

NRC

vii
Introduction

The U.S. Nuclear Regulatory Commission (NRC) has

established nuclear material control and accounting

(MC&A) requirements for uranium enrichment

facilities in Section 74.33 of 10 CFR Part 74, Material

Control and Accounting for Special Nuclear Material."

These requirements (1) apply to uranium enrichment

facilities authorized to produce and to possess lowenriched uranium (LEU) of less than 10 wt % U-235

and (2) necessitate the development of objectives,

criteria, and guidance for evaluating the acceptability

of MC&A plans that applicants are required to

submit. Uranium enrichment facilities, because of the

nature of the operations and the types of materials

that will be on-site, pose two unique problems that

are addressed in the NRC's regulations. First, because

the equipment used to enrich uranium to authorized

enrichment levels also can be used to produce higher

enrichment levels, the NRC cannot rule out the

possibility that this may be done through deliberate

misuse of the equipment. Second, the possibility

exists that undeclared source material (SM) or LEU

feed could be introduced into the process equipment

for unauthorized production of enriched uranium.

MC&A performance objectives are established in 10

CFR 74.33 to protect against, detect, and respond to

such possibilities. In general, the objectives are

consistent with MC&A requirements for other NRClicensed facilities that arc authorized to possess and

use more than one effective kilogram of special

nuclear material (SNM) of low strategic significance.

An applicant's fundamental nuclear material control

(FNMC) plan must demonstrate how the basic

capabilities specified in 10 CFR 74.33(c) will be

achieved and maintained and how such capabilities

will be used to achieve the performance objectives

listed in 10 CFR 74.33(a). Aftcr accepting an FNMC

plan and imposing it as a condition of license, the

NRC will judge the adequacy of a licensee's MC&A

performance by inspecting for compliance with

commitments and practices described in the plan.

Because 10 CFR 74.33 is a performance-oriented

regulation, the objectives are defined rather than the

means for achieving them. Thus, applicants and

licensees have many alternatives with regard to how

their MC&A system and program are designed,

managed, and operated. Hence, this document cannot

begin to covcr all possible methodologies that a licensee might use to achieve the desired objectives.

Instead, this document provides examples of

acceptable MC&A approaches commonly or typically

used by uranium enrichment facilities using gas

centrifuge or gaseous diffusion technology.

This document is intended for use by applicants,

licensees, and NRC safeguards licensing rcviewers.

For the most part, recommended criteria are not to be

regarded as rigid, fixed standards. That is, the lower

effectiveness of one procedure relative to a particular

aspect can be tolerated if there is a compensating

feature, or combination of features, that provides an

overall effective safeguards system. Although not

likely, a licensee could fail to meet most of the criteria

recommended in this document and still achieve the

regulatory objectives. In the final analysis, an NRC

reviewer must make a judgement as to whether the

applicant or licensee can achieve with high probability,

without going beyond its FNMC plan commitments,

the objectives stated in 10 CFR 74.33(a). The

recommendations provided herein pertain to both

applicant submitted FNMC plans and any revisions

made to existing approved plans.

The introduction of this document describes the basis

of the nine general performance objectives of 10 CFR

74.33 and the MC&A system features and capabilities

needed to meet the objectives. The chapters that

follow incorporate and expand on (1) the general

performance objectives and (2) the system features and

capabilities. The chapters are arranged in a different

sequence from the rule making and provide applicants

or licensees an outline for the FNMC plan.

The body of an FNMC plan, corresponding to

Chapters 1 through 12, shall be a condition of license,

and compliance with the FNMC plan commitments

and related procedures will be inspectable.

Explanations and discussions appearing in the body of

the plan should be detailed and precise, as opposed to

general and vague, so that all parties concerned (i.e.,

NRC licensing reviewers, NRC inspectors, and licensee

personnel responsible for plan execution) have a clear

and nonconflicting understanding as to the what, how,

and when aspects of any given plan commitment.

The annex (or appendix) of an FNMC plan should

provide supplementary and general information about

the facility and the MC&A system [e.g., copies of

blank record forms, site map, process diagrams, an

example standard error of the inventory difference

(SEID) calculation, etc.]. The annex will not be

incorporated as a condition of license and will not be

the basis for inspection. Thus, procedures presented

by the applicant or licensee to satisfy regulatory intent

must be in the plan itself, rather than the annex, and

must provide adequate detail so as not to be largely

dependent on examples or supplementary information

in the annex for proper understanding.

1 NUREG/CR-5734
Performance Objectives and

System Features and Capabilities

Performance Objectives

The general performance objectives that should be

addressed by the FNMC plan are set forth in 10 CFR

74.33. 'The basis on which each of the six general

performance objectives were formed is described in

the following paragraphs of this section.

Maintain Accurate, Current; and Reliable

Information of and Periodically Confirm the

Quantities and Location of Source Material and

Special Nuclear MIterial in the Licensecs

Possession

The purpose of this objective is to confirm the

absence of (or to detect the occurrence of) any

significant loss or theft'of SM or SNM. To

maintain current information of the SM and

SNM in their possession, licensees should have

in place a program that provides timely

information about how much material is in their

possession and where that material resides.

Accurate information means that item quantities

for both the element uranium and the isotope

U-235 are based on' measured values or on

reliable factors. Reliable information means

that the quantity of material in an item and the

location of all items is known (with the possible

exception of items' that have been created,

transferred, or consumed within the past 8

hours) and that the location designations are

specific enough to'provide for the retrieval of

the items in a prompt manner. Reliable

information also means that'the quantities and

locations of all classes of material and items

listed in the accounting records are, in fact,

correct and verifiable (with the possible

exception of items that have been created,

transferred, or consumed within the past 8

hours)..'

The licensee or applicant should accurately

account for all SNM and SM that is received

and shipped. This should be accomplished by

maintaining reliable records that are based on

accurate measurements. 'When a shipment is

received, the licensee should begin monitoring

movement and location of the material within

the facility using item control procedures (1) to

monitor the' location and integrity of items until

they are introduced to the'process and (2) to

ensure that all SM and SNM quantities of

record associated with receipts, shipments,

discards, and ending inventory are based on

measurements. Recommendations on the item

control program is provided in Chapter 6 of this

document, and recommendations on

measurements and measurement control

programs is provided in Chapters 2 and 3,

respectively. Monitoring the material in process

may involve the use of process or material

control data. A detailed and accurate

recordkeeping system for the generated data that

provides knowledge of the material's location on

a timely basis should be maintained to support

this function.

Once a year, at intervals not to exceed 370 days,

the licensee should conduct a total plant

inventory and be able to detect, with at least a

90 percent power of detection, an actual loss or

theft of a detection quantity (DQ) that may have

occurred since the last yearly inventory. A DQ

is a site-specific quantity of U-235, the

magnitude of which is discussed in Chapter 4 of

this document.

The licensee should verify the presence of all

SNM and SM currently possessed by the

enrichment facility, as stated in its accounting

records. This verification should be

accomplished by, (1) a dynamic (i.e.,

nonshutdown) physical inventory of the uranium

and U-235 contained within the enrichment

processing equipment and (2) a static physical

inventory of all other uranium material that is

not within the enrichment process system.

Recommendations pertaining to physical

inventories are detailed in Chapter 5 of this

document. In summary, a total plant inventory

involves:

(1) verifying the presence, on a 100 percent

basis, of all uniquely identified SNM and

SM items listed in the accounting records

(2) measuring (by direct measurement or, if

direct measurement is not feasible, by

indirect measurement) all bulk SM and

SNM quantities on hand (i.e.; all SM and

SNM not in item form)

- (3) measuring any items not previously

measured

(4) verifying the integrity of all encapsulated

items and items affixed with tamperindicating seals

(5) measuring a sample of randomly selected

unencapsulated and unsealed items, based

on a statistical sampling plan, to verify the

previously measured quantities of SNM or

-SM contained in the items

The dynamic physical inventory of uranium in

the enrichment process system should be

3 NUREG/CR-5734
Objectives and Capabilities

performed at intervals not to exceed 65 days.

This inventoiy provides a snapshot" of the

amount of material in process at a given time.

The licensee is expected to strike a material

balance around the processing equipment and

any active feed, product, and tails containers

(e.g., UF6 cylinders in feed or withdrawal

stations). This material balance could rely on

indirect measurements and plant process

parameters to estimate (1) the active material in

the enrichment process, (2) the rate at which

feed is being introduced to the process, (3) the

rate at which product and tails are being

removed from the process, and (4) the amount

of process material deposited inside process

equipment. The amount of material estimated

to be inside the process equipment should be

compared to the MC&A records to provide an

indication as to whether a theft or unauthorized

production may have occurred. The loss

detection sensitivity associated with the

bimonthly dynamic inventories should be

sufficicnt to detect a DQ or greater loss or theft

over a 12-month period with at least a 90

percent power of detection. Chapter 5 also

provides recommendations on the conduct of

these physical inventories.

2. Protect Against and Detect Production of

Uranium Enriched to 10 wt % or More in

U 235 and

3. Protect Against and Detect Unauthorized

Production of Uranium of Low Strategic

Significance

To achieve these two objectives, both of which

are characterized as plant misuse (or

unauthorized production of enriched uranium),

a licensee's program should include monitoring

process operations and monitoring personnel

and process-related activities to provide

detection of unauthorized production of

enriched uranium. Timeliness is (1) an

important aspect of protection and detection

and (2) a function of the U-235 quantity and

the enrichment level associated with the

potential unauthorized production activity.

The licensee should have a program for

monitoring the isotopic composition of process

material at credible product withdrawal points

to provide high assurance of timely detection of

unauthorized production of uranium

enrichments. During cascade startup

operations, transient isotopic assays of between

10 and 20 wt % U-235 may occur. These

transients normally are less than 4 hours in

duration. The higher assay material produced

during the transient should remain in and not be

withdrawn from the cascade. Independent

monitoring should be performed when the

enrichment process system is expected to

undergo an assay transient. The monitoring

program can use process control data and

samples that can be validated and verified or can

use duplicate measuring systems, if necessary.

The enrichment technology installed may

determine the extent of the monitoring program.

For example, gaseous diffusion technology

requires a limited program because of the

difficulty in reconfiguring the equipment to

produce higher enrichments in a short time;

however, gas centrifuge technology will require a

more extensive monitoring program because of

the feasibility of reconfiguring the equipment to

produce higher enrichments in a relatively short

period of time. The program can use

nondestructive assay (NDA) techniques with

fixed or portable detectors or the taking of

samples to be analyzed for U-235 abundance.

The theoretical possibility of misusing the

equipment or plant for unauthorized production

differs for each enrichment technology.

Following are some example scenarios for each

of the main enrichment technology typcs.

Centrifue -This technology is sensitive to

misuse because of the large number'of machines

deployed and the possibility for isolating

individual cascades. Cascades could be

temporarily isolated (e.g., valved off) from the

building process piping and, with temporary

piping and with covert feeding of process

material, used to produce higher-than-licensed

enrichments or to produce greater-than-recorded

quantities. Other operating parameters in the

licensed production line could be surreptitiously

altered'to mask the scenario. Surreptitious

feeding of SM or SNM should be considered

among the possible misuse scenarios.

Gaseous Diffusion - This technology is more

difficult to misuse than centrifuge; however,

higher-than-licensed enrichments can be

achieved by batching material repetitively

through the same process equipment. Product

from one pass could be refed and further

enriched in a second or third pass through the

cascade. However, establishing equilibrium

status takes a relatively long time (i.e., weeks),

and feeding the product from one pass would

probably require use of autoclavc equipment at

the plant's designated feed points. More

credible misuse scenarios for this technology are

(1) altering process parameters to produce more

than an authorized amount of product at

NUREG/CR-5734 4
I I Objectives and Capabilities

licensed enrichment levels (but with reduced

tails enrichment values) and '(2) producing more

than an authorized amount of product by

feeding more than the reported quantity of

normal uranium.

Laser Isotope Separation -Final design of a

commercial plant has not been determined;

therefore, misuse scenarios cannot be fully

identified at this time. In general, however,

expectations are that operating parameters may

be changed to produce higher-than-licensed

enrichments from natural uranium feed.

Because of maintenance requirements, the

process approximates a batch-processing system

and, in this respect, is quite different from the

centrifuge and gaseous diffusion processes,

which are generally continuous. Unauthorized

feed and the corresponding unreported product

and tails are a credible possibility for misuse.

For all three technologies, the program should

be capable of detecting the introduction of any

feed material not declared or entered into the

facility MC&A system. Additional

recommendations pertaining to the monitoring

program are provided in Chapter 9.'

The program should be managed and

maintained independent of the production or

operations organization but should not be

cxcluded from using process monitoring and

production control data.

4. Rcsolve Indications of Missing Uranium

The licensee or applicant should have a

formalized program to resolve any indication

that SM or SNM is missing. Resolution of such

indicators means that the licensee has made a

determination that a theft or loss of SM or

SNM has not occurred. As stated in 10 CFR

74.33(c)(6), only indications that suggest a

possible loss from items greater than 500 grams

of U-235 need to be investigated; a possible loss

detected during a material balance closure needs

to be investigated as stated in 10 CFR

74.33(c)(4). Multiple loss indications from

items within a material balance period must be

resolved even though ihe loss from each event is

less than 500 grams of U-235. This resolution

need not occur until the tot-al potential loss

exceeds 500 grams of U-235.

Resolution of an indicator depends on the type

of indicator. Anomalies at uranium enrichment

plants can indicate a number of scenarios from

simple theft to isotopic substitution concealing

diversion of product material. The resolution

process in some cases should begin with a

thorough review of the MC&A records to locate

blatant errors. These errors might include

omissions of entire items, incorrect entries to

computer programs or records, transcription

errors, incorrect estimates of the amount of

holdup in equipment, or calculational errors. A

detailed examination of the MC&A records for

each material type should identify gross errors.

The next stage in the resolution process would

be to isolate the process or storage area that

appears to be causing the anomaly. Once this is

accomplished, all of the information that

contributed to the SM and SNM quantities for

that location should be verified. If resolution

still is not accomplished, the licensee should

remeasure and'sample material in the process or

storage areas to verify quantities. If the

investigation of an indicator results in a

determination that an actual loss or theft has

occurred, the loss or theft must be reported to

NRC pursuant tol10 CFR 74.11.

S. Resolve Indications of Production of Uranium

Enriched to 10 wt % or More in U-235 and

6. Resolve Indications of Unauthorized Production

of Uranium of Low Strategic Significance

Licensees or applicants are responsible for

developing and following a formalized program

designed to resolve indications of unauthorized

production. Resolution of such an indicator

means that the licensee has made a specific

determination that (1) production of excess

quantities of uranium enriched to less than 10

wt % U-235 and (2) enrichment of uranium to

10 wt % or more in U-235 have not occurred.

The resolution process 'should include the

investigation of all information contributing to

the indication of unauthorized production. The

location of the indicators should be determined

and the process area or storage area isolated to

verify the indication. Instruments and

measurement systems used for monitoring

should be examined to determine if they are

functioning properly; remeasurements should be

conducted as necessary. A thorough

examination of the processing equipment should

be performed to ensure that unauthorized

modifications have not been made. The

presence of uranium enriched to 10 wt % or

more in U-235 should be verified through

remeasuring the material in question whether in

item form or in process equipment. The

material contained in the suspect container or

enrichment process equipment should be

measured by NDA or mass spectrometric

analysis to determine the U-235 isotopic

;5 NUREGiCR-5734
Objectives and Capabilities

abundance. Additional information and

recommcndations pertaining to the

identification, investigation, and resolution of

indications of unauthorized production are

provided in Chapter 10 of this document.

If an investigation results in a licensee determination

that unauthorized production has taken place, this

finding must be reported to the NRC within 1 hour of

such determination pursuant to 10 CFR 74.11.

7. Provide Information to Aid in the Investigation

of Missing Uranium and

8.' Provide Information to Aid in the Investigation

of the Production of Uranium Enriched to 10

Percent or More in the Isotope U-235 and

9. Provide Information to Aid in the Investigation

of Unauthorized Production of Uranium of Low

Strategic Significance

If the NRC and/or other government agencies

deem it necessary to conduct an investigation

relating to actual (or highly suspected) events

pertaining to missing uranium or unauthorized

' enrichment, the licensee is to provide, without

specifically being asked, any information deemed

relevant to (1) the recovery of material involved

in a loss, theft, or. diversion and (2) the

investigation of unauthorized enrichment

activities. That is, the burden shall be on the

licensee t provide (without being asked to) all

information that it recognizes as being relevant,

as opposed to providing only information that

the investigators are knowledgeable enough to

request. Additional information and

recommendations pertaining to providing

information to aid in investigations are provided

in Chapter 11 of this document.

System Features and Capabilities

To meet the nine general objectives, the MC&A

system depends on features and capabilities as follows

and as described in Chapters 1 through 12 of this

document.

(1) A management structure that ensures: (a) clear

overall responsibility for MC&A functions, (b)

independence of MC&A management from

production responsibilities, (c) separation of key

MC&A responsibilities from each other, (d) use

of approved written MC&A procedures, and (e)

the periodic review of these procedures.

(2) A measurement program that ensures that all

quantities of SM and SNM in the'accounting

records are based on measured values.

(3) A measurement control program that ensures

that (a) measurement biases are' estimated,

minimized through implementation of

measurement control programs, and eliminated

(if statistically significant) from inventory

difference values of record; (b) all MC&A

measurement systems are controlled so that

twice the standard error of the inventory

difference, based on all measurement contributions, is less than the greater of 5,000 grams of

U-235 or 0.25 percent of the active inventory for

each total plant material balance; and (c) any

measurements performed under contract are

controlled so that the, licensee can satisfy the

requirements of 3(a) and 3(b).

(4) A physical inventory program that provides for

(a) performing (unless otherwise required to

satisfy 10 CFR Part 75) a dynamic (i.e.,

nonshutdown) physical inventory of in-process

uranium and U-235 at least every 65 days and

performing a static physical inventory of all

other uranium and U-235 contained in enriched,

normal, and depleted uranium located outside of

the enrichment processing equipment at least

every 370 calendar days (with static physical

inventories being conducted in conjunction with

a dynamic physical inventory of in-process

uranium and U-235 so as to provide a total

plant material balance at least' every 370

calendar days); and (b) reconciling and adjusting

the book inventory to the results of the static

physical inventory and resolving, or reporting an

inability to resolve, any inventory difference that

is rejected by a statistical test (which has a 90

percent power of detecting a discrepancy of a

quantity of U-235 established by NRC on a sitespecific basis) within 60 days after the start of

each static physical inventory.

(5) A detection program, independent of

production, that provides high assurance of

detecting (a) production of uranium enriched to

10 wt % or more in U-235 to the extent that

SNM of moderate strategic significance could be

produced within 370 calendar days, (b)

production of uranium enriched to 20 wt % or

more in U-235, and'(c) unauthorized production

of uranium of low strategic significance.

(6) An item control program that assures that (a)

current information is maintained for items with

respect to identity, uranium and U-235 content,

and stored location; and (b) items are stored and

NUREG/CR-5734 6
Objectives and Capabilities

handled, or subsequently measured, in a manner

so that the amount of U-235 involved in any

unauthorized removal of items, or uranium from

items, greater than 500 grams of U-235 will be

detected. Exempted from 6(a) and 6(b) are

licensee-identified items each containing less

than 500 grams of U-235 up to a cumulative

total of 50 kilograms of U-235 and items

existing for less than 14 calendar days.

(7) A resolution program that assures that any

shipper-receiver differences (SRDs) are resolved

that are statistically significant and exceed 500

grams of U-235 on (a) an individual batch basis

and (b) a total shipment basis for all SM and

SNM.

(8) An assessment program that (a) independently

assesses the effcctiveness of the MC&A system

at least every 24 months, (b) documents the

results of the above assessment, (c) documents

management's findings on whether the MC&A

system is currently effective, and (d) documents

any actions taken on recommendations from

prior assessments.

The MC&A recordkeeping requirements of 10 CFR

74.33 are as follows:

(1) Each licensee shall establish records that will

demonstrate that the performance objectives

and the system features and capabilities have

becn met and will maintain these records in an

auditable form, available for inspection, for at

least 3 years, unless a longer retention time is

required by 10 CFR Part 75.

(2) Records that must be maintained pursuant to 10

CFR Part 74 may be the original or a

reproduced copy or a microform, if such

reproduced copy or microform is duly

authenticated by authorized personnel and the

microform is capable of producing a clear and

legible copy after storage for the period specified

by NRC regulations. The record also may be

stored in electronic media with the capability for

producing on demand legible, accurate, and

complete records during the required retention

period. Records such as letters, drawings, and

specifications must include all pertinent

information such as stamps, initials, and

signatures.

(3) The licensee shall maintain adequate safeguards

against tampering with and loss of records.

The following chapters of this document incorporate

and expand on the performance objectives and on the

system features and capabilities of 10 CFR 74.33. The

chapters are arranged in a format and sequence to

provide applicants and licensees an outline for the

FNMC plan.

7 NUREGICR-5734
1 Organization

1.1 Corporate Organization

The corporate structure should be described in detail,

and all corporate organization positions that have

responsibilities related to MC&A at the licensee's site

should be identified. 'A description of the corporatelevel functions, responsibilities, and authorities for

MC&A program oversight and assessments should be

provided. At least one corporate official should have

responsibilities pertaining to the control and

accounting of all SM and SNM possessed by the

licensee.

1.2 Plant or Site Organization

A description of the site's management structure

emphasizing MC&A should be provided. By means of

comprehensive organization charts, the site

management structure should be shown. As a

minimum, the charts should indicate where the

responsibility lies for the following functions:

(1) overall MC&A program or system

(2) SM and SNM custodianship

(3) receiving and shipping of SM and SNM

(4) analytical laboratories

(5) bulk and NDA measurements

(6) sampling operations

(7) measurement control program

(8)

(9)

physical inventories

monitoring program to deter and to detect

unauthorized enrichment activities

(10) on-site nuclear material handling operations

A brief description should be provided for each sitelevel position, outside of the MC&A organization,

that has responsibilities relating to MC&A activities

(e.g., sampling, mass measurements, analytical

measurements, and measurement control). For each

position, the functions, responsibilities, and authorities

should be clearly described.

1.3 MC&A Organization

An organizational chart and position-by-position

description of the entire MC&A organization should

be provided. An individual should be designated as

the overall manager of the MC&A program. To

ensure independence of action and objectivity of

decision, the MC&A manager should either (1) report

directly to the plant or site manager or (2) report to

an individual who reports directly to the plant or site

manager and who has no production responsibilities.

13.1 Responsibilities and Authority

A description that clearly indicates the responsibilities

and authority of each supervisor and manager should

be provided for' the various functions within 'the

MC&A organization. The description should indicate

how the activities of one functional unit or individual

serve as a control over,'or checks on, the activities of

other units or individuals. The FNMC plan should

explain how coordination is achieved and maintained

between the MC&A organization and other plant

organizational groups that perform MC&A-related

activities. A definitive statement should be made

specifying that the MC&A manager will review and

approve all written MC&A procedures, and any future

revisions, both inside and outside of the MC&A

organization, pertaining to MC&A-related activities.

In addition to the MC&A manager function, the

functions to be addressed should include, as a

minimum, the' following:

(1) nuclear material accounting

'(2) measurement control program

(3) item control program

(4) statistics

(5) monitoring program to detect unauthorized

enrichment activities

The discussion pertaining to statistics should identify

those individuals responsible for such activities as

calculation of the SEID, determination of active

inventory, evaluation of SRDs, and determination of

control limits.

Whenever more than one key MC&A function is

assigned to the same person, the FNMC plan should

clearly describe the checks and balances that preclude

the following:

(i) performance of accounting or record control

functions by individuals who also generate

source data

(2) any individual from having sole authority to

overcheck, evaluate, or audit information for

which he or she is responsible

9 NUREG/CR-5734
Organization

1.3.2- MC&A Procedures

MC&A procedures to be described are those

written procedures which, if not performed correctly,

could result in a failure to achieve one or more of the

performance objectives of 10 CFR 74.33(a) and the

features and capabilities of 10 CFR 74.33(c). All

MC&A procedures should be identified in the body of

the FNMC plan. The FNMC plan also should contain

a definitive statement that the procedures will be

followed. This set of MC&A procedures should, as a

minimum, adequately address the following topics,

rcgardless of which facility organizational group is

responsible for the particular topic::

I(1)

(2)

accountability record system

sampling and measurements

(3) measurement control program

(4) item control program

(5) static and dynamic physical inventories

(6) investigation and resolution of loss indicators

(7) investigation and resolution of indicators of

unauthorized enrichment to 10 wt % or more in

U-235

(8) monitoring program to detect unauthorized

production of uranium to enrichments less than

10 wt % U-235

(9) determination of SEID, active inventory, and

inventory difference

(10) providing information to aid in investigations

(11)

(12)

MC&A recordkeeping system 

independent assessment of the effectiveness of

the MC&A program -

1.4 Training and Qualification

Requirements

This section of the FNMC plan should describe the

training programs to be established and maintained to

provide qualified personnel and to provide for the

continuing level of qualification with respect to

personnel assigned to MC&A responsibilities.

Training procedures and qualification criteria should

be discussed in definitive statements. Minimum

qualification requirements should be stated for each

key MC&A position.

1.5 MC&A System Description

The length of this section and its level of detail will be

dependent on the information provided in the previous

sections of this chapter. The overall MC&A

organization should be described in a manner that

explains how the nine general performance objectives

of 10 CFR 74.33(a) and the features and capabilities of

10 CFR 74.33(c) will be effectively achieved.

The individual who has responsibility for the following

MC&A-related functions should be spccified by title:

(1) overall MC&A program management (Note:

This individual should have no major nonMC&Arelated responsibilities.)

(2) measurements [Note:- Responsibility may be

divided on the basis of type of measurements (e.g.,

analytical laboratory measurements, NDA

measurements, bulk measurements, and

sampling).]

(3) measurement control and statistics

(4) accountability records

(5) item control

(6) physical inventories

(7) custodial responsibilities (e.g., SM and SNM

storage and movement controls)

(8) monitoring program for detecting unauthorized

enrichment activities

(9) investigation and resolution of indicators that

suggest possible loss or possible unauthorized

enrichment activities

(10)

(11)

receiving and shipping of SM and SNM

analytical laboratories

(12) MC&A recordkeeping system and controls

The information in this chapter should include a

description of the policies, instructions, procedures,

duties, responsibilities, and delegation of authority in

sufficient detail to demonstrate the separation or

overchecks built into the MC&A system.

NUREG/CR-5734 10
2 Measurements

2.1 Measurement Points

The FNMC plan should identify and describe each

measurement that is used, either for accounting

purposes or for a monitoring program, to detect an

unauthorized activity. Measurements (1) establish the

quantities in each custodial area, material balance area

(MBA), or item control area (ICA) and in the facility

as a whole, and (2) contribute to the desired capability

to localize losses and to generate and to assess alarms.

Typically, measurement points and/or sampling

stations are selected to provide quantitative

information about material flows and inventories that

will permit detection and localization of any loss or

diversion, or confirmation that no diversion has

occurred. Essentially all nuclear material shipments

and receipts to and from either diffusion or centrifuge

enrichment plants involve UF6 in metal cylinders.

Various non-UF6 materials are present at the plant as

a result of process equipment maintenance, process

vent gas trapping systems, routine equipment

decontamination and cleaning activities, and

laboratory operations. Typically, three functional

types of MBAs and ICAs are present: (1) processing,

(2) storage, and (3) receiving and shipping. The

identification and definition of measurement points

for processing MBAs are necessary because of the

physical, chemical, or isotopic changes of the nuclear

materials that occur in these MBAs. The storage and

the receiving and shipping areas are typically ICAs.

Typical processing MBAs include (1) the cascade or

isotope separations facilitics, (2) decontamination and

recovery areas, (3) laboratory, and (4) feed and

product sampling and transfer areas.>

2.2 Measurement Systems

The FNMC plan should describe in detail each

measurement system used for nuclear material

accounting purposes. The principal elements and

operations involved in the measurement systems for

MC&A at uranium enrichment plants cncompass mass

(or weight) or volume determination; sampling;

chemical, nondestructive, and isotopic analyses; and

process monitoring operations (for pressure, volume,

temperature, and impurities) unique to the

enrichment process operations. Each measurement

system also should be defined or identified by its

unique set of the following parameters: (1)

measurement device or equipment used, (2) standards

used for calibration, and (3) standards used for

control. Additionally, for analytical laboratory

measurements, the following also should be identified:

(1) sampling technique and equipment used, (2)

sample aliquoting technique, and (3) sample

pretreatment methodology. Elements of the

measurement control program (e.g., standards

traceable to a national system) used for validating and

determining control limits, precision, and accuracy

levels for each measurement element used for

accountability are described in Chapter 3.

The FNMC plan should provide descriptions for each

measurement system associated with bulk, analytical,

and NDA measurements, and should identify, where

applicable, any other measurement systems used for

accounting purposes that do not fall within these

categories.

2.2.1 Bulk Measurement Systems

For each mass (or weight) system, the applicant or

licensee should specify the weighing device, the type of

container(s) weighed, material within the containers

being weighed, capacity of the weighing device, range

to be used, and sensitivity of the device. The

description should include the capacity and the

sensitivity of the scale (e.g., capacity not to exceed X

kilograms, and sensitivity to be at least as good as Y

grams).

For each volume measurement system, the FNMC plan

should identify the vessel (e.g., tank, column, etc.),

capacity of the vessel to which the measurement

applies, the material being measured, the volume

measuring device and instrumentation, the sensitivity

of each device and system, and the range of operation

and/or calibration.

2.2.2 Analytical Measurement Systems

For each analytical measurement system, the FNMC

plan should specify the following:

(1) type of material or chemical compound (e.g.,

UF6, uranium alloy, U308, uranyl nitrate

solution)

(2) sampling technique

(3) sample handling (i.c., pre-analysis sample storage

and treatment)

(4) analytical method used

(5) characteristics measurcd (e.g., grams of uranium

per gram sample, U-235 isotopic composition)

(6) measurement interferences

(7) cxpected measurement uncertainty

2.2.3 NDA Measurement Systems

For cach NDA measurement system, the FNMC plan

should identify the following:

11 NUREG/CR-5734
Measurements

(1) the NDA equipment package (i.e., detector and

electronics)

(2) the type of container measured

(3) SM or SNM material type

(4) attribute measured

(5) measurement configuration (including source to

detector distance)

(6) calculational method

(7) expected measurement uncertainties

2.2.4 Other Measurement Systems

If applicable, the FNMC plan also should identify any

other measurement systems used for accounting

purposes that do not fall within the three categories

covered by subsections 2.2.1. 2.2.2, and 2.2.3. For

example, the measurement systems used for

determining the enrichment process system inventory

should be identified.

2.3 Measurement Uncertainties

The expected measurement uncertainties of the

described measurement systems should be provided.

Variance components for calibration, sampling,

random, and systematic error for each measurement

system should be stated. The units in which the errors

are expressed should be clearly identified.

2.4 Measurement Procedures

The licensee or applicant should make a definitive

statement that an approved measurement procedures

(i.e., methods) manual, or set of approved manuals,

will be cstablished and maintained. The organizational

units that are responsible for the preparation, revision,

and approval of measurement procedures should be

stated. A definitive statement also should be made

that a periodic review of the procedures will be

conducted.

A clear statement should be made that a measurement

procedure can not be used for accountability purposes

without documented approval. Each procedure should

be approved by the overall MC&A manager and by the

manager of the organizational unit responsible for

performing the measurement. Measurement

procedures also should be approved by the

measurement control program manager.

The FNMC plan should provide a definitive statement

that all SM and SNM quantities in the material

accounting records will be based on measured values

and that measurement systems will be maintained for

the measurement of all SM and SNM associated with

the following:

(1) additions to inventory (e.g., receipts)

(2) removals from inventory (e.g., shipments and

measured discards)

(3) material on ending inventory

For receipt of material, the licensee may use shipper's

measured values rather than its own measurements,

provided that () a shipper-receiver comparison, based

on attributes or confirmatory measurements, shows no

significant SRD las defined by 10 CFR 74.33(c)(7)]; or

(2) in the case of a significant difference between

shipper and receiver, no significant difference exists

between shipper's value and the umpire value used to

resolve the difference. However, when booking

shipper's values, the shipper's measurement

uncertainty should be used when determining SEID.

NUREGICR-5734 12
3 Measurement Control Program

3.1 Orgpnization and 'Management

Thc organization and management of the

measurement control program should be described in

sufficient detail to show how the measurement quality

assurance function is assigned and how independence

from the analytical laboratory and other units

performing either sample taking or measurements is

maintained. The measurement control program

manager should be at a management level that is

sufficiently high to ensure objectivity and

independence of action. Thus, the measurement

control program manager should either report directly

to the overall MC&A manager or, if in a different

organizational unit, be on the same level as the

MC&A manager.

The licensee's measurement control program should

be properly managed to ensure adequate calibration

frequencies, sufficient control of biases, and sufficient

measurement precision to achieve the capability

required by 10 CFR 74.33(c)(3).

3.1.1 Functional Relationships

The relationship and coordination between the

measurement control program manager, the analytical

laboratory, and other measurement performing groups

necds to be clearly defined. Adequate assurance

should be provided that the measurement control

program manager has the authority to enforce all

applicable measurement control requirements.

3.1.2 Procedures

The measurement control program procedures should

be established and maintained in a manual that is kept

current and readily available. This manual should

contain all the currently applicable written procedurcs

pertaining to measurement control and measurement

quality assurance.' Responsibility for preparation,

revision; and approval of manual procedures should be

specified. Individual measurement control procedures

should have documented approval by the - -

measurement control program manager. The

procedures should address the following:

(1) calibration frequencies and methods'

(2) standards used for calibration (i.e., description

and storage controls)

(3) standards used for control (i.c., method of

obtaining or preparation, and traceability)

(4) control standard measurements

(5) replicate sampling and replicate measurements

(6) verification of process control instrumentation

through comparison with other process

instruments

(7) control limits and control responses

(8) generation and collection of control data

(9) recordkeeping controls and requirements

3.1.3 Contractor Program Audits and

Reviews

If measurement services are provided by an outside

contractor or off-site laboratory, the review program

used to monitor the off-site measurements should be

described. Such reviews are to ensure that the

contractor or off-site laboratory has an acceptable

measurement control program to the extent that use of

the contractor's measurements will not compromise

the licensee's ability to meet any measurement or

measurement control requirement contained in either

10 CFR 74.33(c) or in its FNMC plan. An initial

review of the contractor's measurement control

program should be conducted before licensee use of

measurements performed by the contractor or off-site

laboratory.

All contractor or off-site laboratory assessment

findings and recommendations should be documented

and submitted to both the measurement control

.program manager and the overall MC&A manager

within 30 days of completion of the review. The two

managers should arrive at an agrcement on corrective

actions that should be taken, based on their evaluation

of the report, and should transmit these findings to the

contractor or off-site laboratory in writing. Thc

licensee should not use measurements performcd by

such contractors or off-site laboratories until they have

verified that the corrective actions have been

instituted.

The persons who conduct a contractor review need not

be employed by the licensee; but they should not be

employed by, or in any way associated with, the

contractor or off-site laboratory so that the

independence of the conclusions may be maintained.

3.2 Calibrations

The FNMC plan should summarize the licensee's

calibration program and confirm that the licensee has

written procedures covering the following topics:

(1) calibration frequency for each measurement

device or system

13 13NUREG/CR-5734
Measurement Control

(2) identification of the reference standards used for

calibration of each measurement device or

system

(3) protection and control of standards used to

calibrate measurement systems to maintain the

validity of their certified or assigned values

(4) the range of calibration for each measurement

device or system and the minimum number of

calibration runs (observations) needed to

establish a calibration

Unlike control standards, standards used for

calibrating measurement systems need not be

representative of the process material or items to be

measured by the calibrated device or system. If

practical, the standard used during the calibration

process should be subjected to all the steps involved

in the measurement- process that the process

unknowns are subjected to (e.g., sample pretreatment),

but this need not always be the case. It is the primary

measurement device, not necessarily the entire:

measurement system, that needs to be calibrated,

especially when the primary measurement device is

common to two or more measurement systems. For

example, the Davies & Gray titrimetric method is

often used to analyze samples for uranium

concentration of two or more different material types

(e.g., UF6, U308 , and uranyl nitrate solutions). In this

case, more than one measurement system is involved

because different sampling and sample pretreatment

methods and different control standards are used.

The potassium dichromate titrant, however, is

common to the systems; thus, the titrant is what is

calibrated (or standardized) with a reference standard

such as certified U308 or certified uranium metal.

In the case of nonconsumable standards used to

calibrate measurement systems (e.g., weight standards),

the frequency of recertiication of assigned values

should be specified. The recertification frequency

should be dependent on how often the standards arc

handled, the standard's stability, and the adequacy of

the controls used to maintain the integrity of the

standards. Biannual recertifications of such standards

are usually acceptable.

The FNMC plan should contain a definitive statement

that no SM or SNM accountability value will be based

on a measurement that falls outside the range of

calibration. The FNMC plan also should identify

those measurement systems that are point-calibrated.

A point-calibrated measurement system is one in

which the following are true:

(1) The entire measurement system is calibrated

with a standard or set of standards that are

representative of the process unknowns that are

imeasured by the system. That is, the

representative calibration standard(s) undergoes

all the measurement steps, and in the same

manner, that the unknowns do.

(2) One or more calibration standards are processed

and measured along with each unknown or set

of unknowns measured. That is, both the

standard(s) and unknown(s) are measured during

the same general time interval, with the same

individual measuring both the standard(s) and

unknown(s).

(3) The measurement values assigned to the process

unknowns are derived from the measurement

response observed for the standard(s) that was

measured along with the unknown(s).

(4) The measurement response for each unknown

must fall within plus or minus 10 wt % of the

response for a standard measured at the same

time as the unknown, or as in the case of a low

concentration unknown, the difference between

the unknown's response and the standard's

response should be less that four times the

standard deviation associated with the standard's

response.

3.3 Control Standard Program

For those measurement systems that are not pointcalibrated, a defined program for the periodic

measurement of control standards should be

established and followed. Control standard

measurements serve the dual purpose of (1)

monitoring the stability of a previously determined

calibration factor, and (2) estimating the system bias

over a period of time (e.g., an inventory period). The

minimum total number of control standard

measurements during the time period, as well as the

typical frequency, needs to be specified for each

measurement system. Generally speaking, for each

measurement system, a minimum of two control

standard measurements should be made during each

week that the system is in use. For those systems that

are used less than eight weeks during a given matcrial

balance period, more than two control standard

measurements per week of system use may be

necessary to provide:

(1) a minimum of eight control measurements for

those systems used during the material balance

period to measure material totalling less than

100 kilograms of U-235

NUREGICR-5734 14
Measurement Control

(2) A minimum of 16 control measurements for

those systems used to measure a total of 100 or

more kilograms of U-235

Control standards should be representative of the

process material or items being measured. To be

representative, the standards need not always be

identical to the process unknowns; but any constituent

of the process material, or any factor associated with a

process item, that produces a bias effect on the

measurement should be present to the same degree in

the control standards. For scales used to weigh very

large items, such as UF6 cylinders, the control standard weights should be artifact cylinders (i.e., both

empty and full) of certified mass to avoid a bias effcct

caused by buoyancy or point loading.

For each measurement system that is not pointcalibrated, the control standards to be used for control

standard measurements should be identified and/or

described. Along with material composition and

matrix factors, biases also can be induced by changes

in (among other things) temperature, humidity, line

voltage, and background radiation. Biases also can be

operator or analyst induced. Therefore, the

scheduling of control standard measurements should

be based on the following considerations:

(1) Does the variation between analysts or

operators need to be considered and hence

monitored?

(2) Can environmental variables contribute to

measurement bias?

(3) Is bias likely to vary with respect to the time of

day?

(4) Is a particular bias likely to be long tcrm, short

term, or cyclic in nature?

(5) Is bias a function of the process measurement

values over the range of calibration (i.e., is the

relative percent bias nonuniform over, the range

of calibration)?

(6) What controls or procedures are needed to

ensure that sampling or aliquoting of the

control standard is representative of the

sampling or aliquoting of the process material?

(7) To estimate the bias for each measurement

system, how much alike - in terms of chemical

composition, uranium concentration, density,

homogeneity, and impurity content - should the

control standards be relative to the process

unknowns?

3.4 Replicate Program

Duplicate measurements performed on single samples

(or single items) and/or measurements of replicate

samples are necessary to estimate the combined

analytical and sampling random crror. For

nonsampling measurement systems such as NDA and

weight mcasurement systems, the analytical variance

component can be dcrived either from (1) replicate

measurements performed on the process items, or (2)

the rcplicate data generated from the measurement of

control standards.

The licensee should cnsure that replicate samples are

independent of one another. The number of replicate

samples measured for each analytical mcasurement

system during an inventory period should be equal to

at least one of the following:

(1) 100 percent of the accountability batches

sampled (when less than 15 batches)

(2) the greater of 15 samples or 15 percent of the

accountability batches sampled

(3) 50 samples (when 15 percent of the batches is

greater than 50)

For each measurement system involving sampling and

analysis, the FNMC plan should indicate (1) how many

samples' are taken and measured for each accountability batch measurement,'and (2) how many analyses

are performed on each accountability sample. If two

or more samples are used and two analyses per sample

are performed for each accountability batch

measuremcnt, replicate requirements are automatically

met. If, however, one sample per batch is normally

used for accountability purposes, the replicate program

should include a periodic taking of a second (i.e.,

replicate) sample. Replicate or repeat measurements

can be made on the same or similarproduction items.

The scatter in the repeat measurements is used to

estimate the random error variance using a statistical

technique known as the one-way analysis of variance. -(The statistical methods described in Statistical

Methods for Nuclear Material Management,

NUREG/CR-4604, are recommended by NRC for

.satisfying the statistical requirements of 10 CFR 74.33;

see also Chapter 4 of this document.) Replication not

only improves the precision of results obtained from

the statistical analysis of the measurement data, it also

can detect gross errors in the data.

15 NUREG/CR-5734
Measurement Control

3.5 Control limits

Both warning and out-of-control limits should be

established and used for both control standard and

replicate measurements for those measurement

systems used for nuclear material accountability. For

point-calibrated systems, the assigned value of the

standard(s) measured along with the unknown(s) is

assumed to be valid. If the standard's true value could

change because of factors such as evaporation,

moisture pickup, or oxidation, the value of the

standard should be checked periodically. Therefore,

control limits for the verification measurements

associated with such standards should be established.

This is especially true for those point-calibrated

systems that use a single standard, or aliquots from a

single standard, over any extended period of time.

The warning and out-of-control limits are normally set

by the licensee based on a tradeoff between (1) the

cost of investigating and resolving incidents where

limits are exceeded and (2) the cost of accepting

measurements of poor quality. Warning limits set at

the 0.05 level of significance and out-of-control limits

set at the 0.001 level of significance are usually

sufficient. When a system generates a control

measurement that falls beyond an out-of-control limit,

the system should not be used for accounting purposes

until it has been brought back into control (i.e., within

the upper and lower warning limit).

Control limits should be recalculated at a

predetermined frequency and modified if required.

The FNMC plan should clearly explain how control

limits are established and the frequency for

redetermining them.

3.5.1 Measurement Control Data Analysis

Measurement control data such as control standard

measurement results and the differences between

measurement values of replicate pairs should be

plotted manually on graphs or entered into a

computer data base for generation of control charts.

All control charts should be reviewed at least once

every two weeks unless a measurement system was not

used during that period. The review should assess the

frequency of control data exceeding either the warning

or the out-of-control limits and also evaluate for any

significant trends.

3.5.2 Response Actions

Either the analyst or the operator performing a

control measurement or the supervisor should have the

responsibility for promptly reporting any control

measurement that exceeds an out-of-control limit.

Such reporting should be made to the measurement

control program manager (or his or her designee), who

should have the responsibility and authority to carry

out the necessary response and corrective action.

Minimum response and minimum corrective action

requirements should be clearly defined. In addition,

the measurement control manager (or his or her'

designee) should be responsible for, and have the

authority for, determining and executing additional

response and corrective actions as deemed appropriate.

The minimum response to a reported incident of a

control measurement exceeding an out-of-control limit

should consist of the following:

(1) verifying that the measurement system in

question has been taken out of service with

respect to accountability measurements

(2) documenting the occurrence of the event

(3) performing at least two additional control

measurements

(4) performing additional control measurements, if

results of item 3 do not show the system to be

back in control, using a different control

standard or different replicate sample (as

appropriate), or recalibrating the measurement

system, or making any necessary system repairs

For those measurement systems that make a significant

contribution to the SEID, the response to an out-ofcontrol condition also should include the

remeasurement of any samples (or items) that were

measured before the out-of-control condition but after

the last within-control measurement. The validity of

the previous measurements can be established without

a complete remeasurement of all the samples (or

items) involved if remeasurement on a "last in, first

out" basis is used. That is, the last sample (or item)

measured before the out-of-control measurement,

should be the first to be remeasured, and continuing in

reverse order until two consecutive remeasurements

are found to be in agreement with their initial

measurement at the 95 percent confidence level.

NUREG/CR-5734 16
4 Statistics

4.1 Determination of Measurement

Uncertainties

To achieve the objectives and capabilities of 10 CFR

74.33, each licensee or applicant should institute a

statistical program that evaluates the MC&A data to

ensure that (1) the measurement data are analyzed in

a rigorous manner and (2) hypotheses concerning the

status of the nuclear material possessed are

appropriately tested. NRC sponsored the

development of a comprehensive reference that

specifically addresses the statistical treatment of

measurement control and accounting data. The

statistical methods described in this reference,

Statistical Methods for Nuclear Material Management,"

NUREG/CR-4604, are recommended by NRC for

satisfying the statistical requirements of 10 CFR 74.33.

The FNMC plan should

(1) contain a detailed discussion of the procedures

and methodologies for estimating measurement

variance components

(2) discuss how biases are determined and how bias

corrections are applied, including:

(a) how often biases are estimated

(b) how the bias' effect on the measured

quantity of material in the item is

determined

(c) when and how bias corrections to items

are made

(d) how their effect on inventory difference is

determined

(e) when and how bias corrections are

applied to the inventory difference (ID)

(3) describe the procedure and means for

determining active inventory

(4) provide all relevant information regarding the

determination of the SEID

(5) specify the DQ, which should not exceed 1.3

percent of the annual quantity of U-235

introduced into the enrichment process, except

when 1.3 percent of additions to process is less

that 25 kilograms of U-235, in which case the

DQ need not be less than 25 kilograms of U235

(6) specify the methodology for determining ID

threshold values to be used to provide a 90

percent power of detecting a loss of a DQ, as

required by 10 CFR 74.33 (c)(4). (See Chapter 5

for additional information on inventory

difference limits and response actions.)

There should be a definitive statement in the FNMC

plan for independent verification of the correctness of

the SEID calculation for each total plant material

balance. If the SEID value is calculated using a

computer,; the verification may involve two or more

persons to check for correctness of the input data and

to check the correctness of a sample calculation used

to verify the computer program.

4.2 Determination of SEID

As defined in 10 CFR 74.4, the "standard error of

inventory difference" means the standard deviation of

an inventory difference that takes into account all

measurement error contributions to the components of

the ID. For strategic SNM facilities, nonmeasurement

contributors to the ID are not to be included in the

SEID calculation. However, for facilities possessing

only SNM of low strategic significance, the NRC

allows licensees to take limited credit for

nonmeasurement contributors. It is not really possible

to quantify the nonmeasurement contribution to the

uncertainty associated with an ID, but 10 CFR 74.33

licensees are permitted to assume that the total

nonmeasurement contribution to SEID equals the

total measurement error contribution. When including

only measurement uncertainty, SEID can be expressed

as follows:

k

SEID = [ (G,)z (ar1),2 + ()2 / n I 1/2

where

k = number of measurement systems

Gi = total grams uranium (or U-235)

measured during inventory period by

measurement system i

(ci), = systematic error standard deviation for

measurement system i

(ai), = random error standard deviation for

measurement system i

n = number of batches (items) measured by

measurement system i

When taking the maximum allowable credit for

nonmeasurement contribution (which assumes a 1:1

ratio of measurement to nonmeasurement

contributions),

k

SEID = [2 1 (Gi)2 {(aj),2 + (g)r/n}

i=l I 12

In theory, SEID provides the uncertainty, at the 67

percent confidence level, of the inventory difference.

17 NUREG/CR-5734
Statistics

The FNMC plan must provide all relevant information

regarding the determination of SEID. There should

also be a commitment that at least two individuals

independently verify the correctness of the SEID

calculation for each total plant material balance. If

the SEID value is calculated by a computer, the

verification by two or more persons involves a

checking for correctness of the input data used by the

computer to calculate SEID.

NUREG/CR-5734 18
5 Physical Inventories

5.1 General Description

The applicant or licensee should provide a general

description of how both dynamic (i.e., nonshutdown)

inventories of the enrichment process system and

static inventories of the balance of the plant will be

planned, conducted,'assessed, and reported. For

enrichment facilities using laser isotopic separation

technology, a total plant shutdown inventory may,be

required.

The FNMC plan should contain a definitive statement

that physical inventory functions and responsibilities

will be reviewed comprehensively with the involved

individuals before the start of each dynamic and static

inventory.

For static inventories, a book inventory listing, derived

from the MC&A record system, should be generated

just before the actual start of the inventory, such

listing shall include all SM and SNM that the records

indicate should be possessed by the licensee at the

inventory cutoff time, except for' material to be

covered by the dynamic inventory that is to be

conducted in'conjunction with the static inventory.

For dynamic inventories, a book inventory quantity, to

which the results of the dynamic physical inventory

will be compared, is needed.. One approach to

estimate the in-process inventory is to use a running

book in-process inventory" (RBIPI) technique. The

RBIPI is the quantity of uranium and U-235

calculated as follows:

RBIPI = BI + CI - CO

where

BI = beginning in-process inventory (i.e.,

inventory at the start of the current

inventory period) as determined from the

previous dynamic inventory

CI = cumulative measured input to the

enrichment process for the current

dynamic inventory period.

CO cumulative measured output from the

enrichment process for the current

dynamic inventory period

Hence, the inventory difference associated with a

dynamic physical inventory is derived from the

following equation:

ID = RBIPI - El = (BI + Cl) - (CO +,EI)

where

El ending in-process inventory as determined

from the dynamic physical inventory

The inventory difference and related information

associated with each dynamic physical inventory are to

be reported to the NRC, pursuant to 74.17(a), on an

NRC Form 327 as the results of a physical inventory

associated with material code 89 (uranium in'

cascades). The inventory difference and related

information associated with each static inventory are to

be reported to the NRC on separate NRC Forms 327

for DOE/NRC material type codes 10, 20, and 81 (i.e.,

depleted, enriched, and normal uranium,'respectively).

In addition'to these submittals, the results of the

plant-wide material balance, for total uranium element

and total U-235 isotope (across all four material type

codes), associated with-each annual physical inventory

must be reported on a separate NRC Form 327.

5.2 Organization, Procedures, and

Schedules

The FNMC plan should explain the makeup and duties

of the typical physical inventory organization for both

dynamic and static inventories. The individual having

responsibility for the coordination of the physical

inventory effort should be identified;by position title.

The FNMC plan also should indicate how the

preparation and modification of inventory procedures

are to be controlled.

The FNMC plan should contain a definitive statement

that specific inventory instructions will be prepared

and issued for each dynamic and static inventory.

5.3 Typical Inventory Composition

The typical expected in-process inventory within the

enrichment equipment for both uranium and U-235 at

the time of the dynamic physical inventory should be

specified. Unlike other bulk nuclear material

processing facilities, uranium enrichment facilities

increase the strategic value of the uranium under

complex dynamic operating conditions. For gascentrifuge and gaseous diffusion plants, the in-process

inventory should be specified by accounting for UF6

gas, solid UF6, and residual holdup solids deposited

within equipment.

A typical composition, by material type codes, of a

static physical inventory also should be presented. The

total inventory of UF6 cylinders should be accounted

for by material type (i.e., tails, feed, and product). If

different size cylinders or other containers are used

19 I9NUREG/CR-5734
Physical Inventories

within any of the three UF6 categories, they should be

treated as different item strata.

Enrichment plants typically are divided into a number

of MBAs and ICAs to reflect the functional activities

as follows:

Processingt - An MBA in which occur (1) routine

transfers of nuclear material from one container to

another, (2) changes in isotopic or chemical assay, or

(3) changes in chemical or physical form. Various

measurements are required to define materials flows

through the process and to perform physical

inventories so that periodic material balances can be

completed for the MBA. Because these measurements

have associated uncertainties, a processing MBA will

normally have a nonzero inventory difference for each

inventory. Of the total plant MBAs and ICAs, a

relatively small number might be processing MBAs.

Examples are the isotope separation operations (e.g.,

enrichment cascade facilities); decontamination and

recovery operations; analytical laboratory; and

material rebatching, blending, and sampling

operations. Physical inventories for'the enrichment

process system and decontamination and recovery

operations are the most complex and involve the most

coordination and careful timing.-

Storage -ICAs in which all materials are sealed in

containers with measured values and are being stored

for future processing or shipment. Some minor

sampling of containers can occur in a storage ICA.

Because nuclear materials in a storage ICA are

primarily accounted for on an item basis, a true

storage ICA typically will have a zero inventory

difference for each inventory period when all items are

accounted for and their integrity and previously

documented measured values are confirmed.

Receiving and shipping - An ICA from which

materials are shipped or into which materials are

received from off-site. This ICA type will normally

serve as an interim storage area and will see more

activity (i.e., changes in current inventory) than the

typical storage ICA. At some facilities, sampling and

rebatching of items may occur in this ICA.

5.4. Conducting Dynamic Physical

Inventories

A description of the dynamic inventory methodology,

including cutoff and inventory minimization

procedures, should be presented; and all

measurements (including sampling) should be

identified. The FNMC plan should contain sufficient

information to show how the total in-process

inventory for both uranium and U-235 is obtained.

The means for measuring or estimating residual

process material (i.e., holdup) should be addressed in

detail. The change or variation in such deposited

holdup from one dynamic inventory to the next also

should be discussed.

Because of the size and complexity of a gaseous

enrichment cascade system and the continuous

dynamic operations, a detailed inventory notice should

be prepared for each dynamic inventory. The notice

should be issued to all involved parties and should

contain instructions that define the timing and

performance of various inventory steps and conditions

under which the inventory is to be taken. Specific

sampling points throughout the cascade and 

instructions on data'submission to the accountability

organization should be identified. The instructions

should take into account the current cascade'

configuration (e.g., equipment offstream) and types of

feed and withdrawal streams. The instructions should

highlight any required deviation from normal inventory

procedures contained in the plant's operating

procedures. The basic procedures for the cascade inprocess inventory should (1) maintain the cascade in a

steady-state operating condition for at least 24 hours

before inventory time, (2) record the necessary process

measurement data and collect process samples over a

period of about six hours before inventory time, and

(3) establish'a complete feed and withdrawal system

switch over to pre-inventoried containers at inventory

time'so that the amount of material in the active

containers at the feed and withdrawal stations can bc

measured. Unless special circumstances require a

change, the time for a routine inventory should be

established (e.g., at 2400 hours) on the last'day of the

inventory period. For the gaseous enrichment

processes, the dynamic gas-phase inventory requires

recording gas pressure and temperature readings for

equipment throughout the process system, quantities

of UF6 contained in desublimers (i.e., cold traps) and

chemical traps, and other measurements (e.g.,

concentration of impurity gases). ypically, many data

points are collected during these operations for

calculating the in-process inventory for input into

established computer models and calculation programs.

These programs incorporate fLxed-cascade parameters

such as equipment volumes, compressor circuit

balances, and gas law relationships.

5.5 Conducting Static Physical

Inventories

A description of the procedurcs and methodologies

associated with performing static physical inventories

should be provided in sufficient detail to demonstrate

that valid inventories will be conducted. Such

description should include a general outline of the

following:

NUREG/CR-5734 20
Physical Inventories

(1) organization and separation of functions

(2) assignment of inventory teams and their training

in the use of uniform practices

(3) obtaining, verifying, and recording of source

data

(4) control of inventory forms

(5) assurance that item counts verify the presence

of each item while preventing any item from

being counted more than once

(6) implementation of cutoff and material, handling

procedures for nonenrichment processes (e.g.,

scrap recovery)

Decontamination and recovery also is a complex

operation involving the disassembly and

decontamination of failed pieces of process

equipment, cleaning of UF6 cylinders, and recovery of

uranium from various types of scrap materials. The

basic inventory procedure should involve establishing

a cutoff of movement of materials into the MBA and

processing all materials to a mcasurable form, such as

containers of solution or oxide. Except for the

decontamination enclosure in which in-process

solutions are mixed, sampled, and measured

volumetrically, the inventory process should involve

emptying and flushing of process systems and piping,

which then could be measured using NDA techniques

to establish levels of residual holdup.

Special item storage and handling or tamperindicating methods, which are used to ensure that the

previously measured and recorded SM or SNM

content values can be used for inventory purposes

without remeasurements, also should be described. In

addition, the FNMC plan also should provide a

description of how item identities are verified and how

tampering with the contents of items will be detected

or prevented.

Items that are not encapsulated, affixed with tamperindicating seals, or otherwise protected to ensure the

validity of prior measurements need special attention.

The basis for determining which items are to be

measured at physical inventory time and the justification of any proposed alternatives to measurement

of any SM and SNM included in the inventory should

be presented. If statistical sampling is proposed as an

alternative method to 100 percent verification, the

FNMC plan should describe the sampling plan. Such

description should include:

(1) the method of segregating the types of items to

be sampled (i.e., selected for remeasurement)

(2) the procedure for calculating the sample size

(i.e., the number of items) for each stratum

(3) the quality of the measurement methods used to

verify original measurement values

(4) the procedure for reconciling discrepancies

between original and remeasurement values, and

for scheduling additional tests and

remeasurements

(5) the basis for discarding an original SM or SNM

value and replacing it with a remeasurement

value

One acceptable means for establishing the number of

items (to be randomly selected for remeasurement)

from a given stratum to give the required 90 percent

power of detection of loss of a detection quantity is

given by the following equation:

n = N 11 - (0.10)2q

where

n = number of items to be remeasured

N = total number of items in a stratum

x = maximum U-235 content per item

(kilograms)

g = DQ = detection quantity. (kilograms

-U-235)

The FNMC plan also should contain a definitive

statement that all items on ending inventory that havc

not been previously measured will be measured for

inventory purposes.

The decision rationale for determining when the

element and isotope factors for items, objects, or

containers will be measured directly for inventory and

when they may be based on other measurements

should be presented in the FNMC plan. For example,

if the U-235 contained in liquid waste batches is

derived by applying an average enrichment factor to

the measured uranium element content, the rationale

for such practice (as opposed to measuring each batch

for both uranium and U-235 content) should be

discussed, and the method for establishing the average

enrichment factor should be described.

If the content of items is established through prior

measurements and those items are tamper-indicating

or access to them is controlled, the SM or SNM

quantity in those items may be based on those

measured values. Otherwise, verification of SM or

SNM content can be achieved by reweighing either (1)

all items within a given stratum or (2) randomly

selected items from the stratum based on a statistical

sampling plan. A statistical sampling plan will not be

21 NUREG/CR-5734
Physical Inventories

acceptable if there is any likelihood of any significant

change in the uranium concentration (or weight

fraction) or in the uranium isotopic distribution

because of such factors as oxidation, change in

moisture content, commingling with materials of

different enrichments, or different compositions.

5.6 Inventory Difference Limits and

Response Actions

Each licensee should have a well-defined system for

evaluating both dynamic and total plant IDs and

taking actions when IDs exceed certain predetermined

thresholds. As a minimum, there should be three

response levels for excessive IDs. The following

would be an acceptable approach for three increasing

levels of response actions with respect to static

physical inventories:

Warning-level ID U-235 ID ! 1.7 (SEID) +

500 grams or

U ID : 1.7 (SEID) +

10 kg U

Significant ID U or U-235 ID 2 3 (S

problem

Major ID problem U-235 ID 2 DQ - 1.3

(SEID)

EID)

For dynamic physical inventories, the following three

response levels for excessive IDs would be acceptable:

Major ID problem U-235 ID 2 DQ - 1.3 (SEID) - (cumulative enrichment

process system U-235 ID for

past 10 months)

All of the above limits are expressed in terms of

absolute values of ID without regard for algebraic sign.

The minimum response for a warning-level ID should

be a documented licensee investigation conducted by

the MC&A organization. Such an investigation should

provide a conclusion for the probable cause of the

excessive ID and give recommendations for avoiding

recurrences. When a warning-level ID is positive, it

should be regarded as being equivalent to an indicator

of a possible loss that requires investigation and

resolution (see Chapter 9).

For a significant ID problem, an extensive

investigation by the licensee should be conducted. If a

significant ID problem cannot be satisfactorily

explained, a static or dynamic reinventory may be

needed.

For any unresolved ID determination that remains a

major ID problem (without regard to algebraic sign),

the licensee should conduct a plant-wide reinventory

and investigation. The NRC considers a positive ID

large enough to be a major ID problcm as a very

serious condition.

Warning-level ID

Significant ID

problem

U or U-235 ID 2 (SEID)

U or U-235 ID 2 3 (SEID) The FNMC plan should fully describe in definitive

statements the minimum response actions for each ID

action level.

NUREG/CR-5734 22
6 Item Control

6.1 Organization

The FNMC plan should identify the individual

responsible for overseeing the item control program

by position title. Positions of those individuals who

have significant item control program responsibilities

also should be identified.

6.2 General Description

The applicant or licensee should state that the overall

MC&A system will maintain a record of all SM and

SNM items, regardless of quantity or duration of

existence. In addition, the item control program

should provide current knowledge of the location,

identity, and quantity of all SNM and SM contained in

all items that are not exempt from item control.

Items that can be exempt from item control program

coverage are:

(1) items having an existence time of less than 14

calendar days

(2) any licensee-identified items listed by material

-type containing less than 500 grams of U-235

each but not to cxceed a plant total of 50

kilograms of U-235

Each item that is not exempt from the item control

program should be stored and handled in a manner

that cnables detection of, and provides protection

against, unauthorized or unrecorded removals of SM

and SNM. All items, whether or not they arc subject

to item control rogram'coverage, should have a

unique identity. For items subject to the item control

program, the following are acceptable means for

providing unique identity:

(1) a unique alpha-numeric identification on a

tamper-indicating seal applied to a containcr of

SM or SNM

(2) a unique alpha-numeric identification

permanently inscribed, embossed, or stamped on

the container or item itself

(3) a uniquely prenumbered (or bar-coded) label

applied to each item having good adhesive

qualities such that its removal from an item

would preclude its reuse

Location designations shown by the MC&A records

need not be unique, but location designations should

be specific enough so that any item may be located

within 1 hour. Longer times may be acceptable but

should be further justified in the FNMC plan. The

MC&A record system should be controlled in such a

manner that the record of an item's existence cannot

be destroyed or falsified without a high probability of

detection. Each nonexempt item should be stored and

handled in a manner that enables detection of, and

provides protection against, unauthorized or

unrecorded removals of SM and SNM.

6.3 Item Identity Controls

Descriptions should be provided of the item records

showing how items are identified for each material

type and each type of container. If the unique number

on a tamper-indicating seal is the basis for providing

unique item identity, the FNMC plan should:

(1) describe the type of seal used

(2) describe how the seals are obtained and what

measures are implemented to ensure that

duplicate (counterfeit) seals are not

manufactured

(3) describe how the seals are stored, controlled,

issued, and accounted for

(4) describe how seal usage and disposal records are

maintained and controlled

Similar information should be provided for other

methods of unique item identity (e.g., labels).

6.4 Storage Controls

Item storage areas and controls should be fully

described in the FNMC plan. In particular, controls

that are used as the basis for ensuring the values of

prior measurements, as opposed to remeasuring the

item at inventory time, should be discussed in detail

and the Tationale for accepting prior measurements

explained. Any controls used to ensure the validity of

prior measurements should be equivalent to the

protection provided by tamper-indicating seals.

Both administrative controls (e.g., custodian

assignments and limiting authorized access to storage

areas) and physical controls (e.g., locked and alarmed

doors) should be identified.

6.5 Item Monitoring Methodology and

Procedures

As part of the item control program, a licensee should

maintain a system of item monitoring that:

(1) verifies that items shown in the MC&A records

are actually stored and identified in the manner

indicated in the records

23 NUREG/CR-5734
Item Control

(2) verifies that generated items and changes in

item locations are properly recorded in the

MC&A record system in a timely manner

(3) can detect, with high probability, any real loss of

items, or uranium from items amounting to 500

grams or more of U-235

The item monitoring system should conduct the

following activities at least on a monthly basis:

(1) for each item inventory stratum, compare the

actual storage status to the recorded status of a

sufficient sample of randomly selected items

from the item control program records

(2) for each item inventory stratum, check the

accuracy of the MC&A records for a sufficient

sample of randomly selected items from each

storage area

(3) check the accuracy of a sufficient sample of

randomly selected production records of created

and consumed items

The actual frequency of the above activities, and the

size of the random sample, should be a function of the

expected discrepancy rate based on prior observations.

The FNMC plan should contain definitive

commitments for resolving discrepancies.

6.6 Description of Typical Item Strata

The FNMC plan should describe the expected item

population in terms of the following:

(1) type of item (i.e., stratum)

(2) expected range of the number of items within

each stratum

(3) the average uranium and U-235 content of the

items within each stratum

(4) the expected rate of item generation and

consumption for each stratum

6.7 Investigation and Resolution of

Item Discrepancies

The applicant or licensee should provide definitive

statements of the procedures and controls that will

ensure that all incidents involving missing or

compromised items or falsified item records will be

investigated. A compromised item is (1) one

displaying evidence of tampering or (2) an

unencapsulated and unsealed item assigned to a

controlled, limited-access storage area that is found

elsewhere.

If any unsealed or unencapsulated item is located after

having been determined to be missing, or if an item is

found to be compromised, the contents should be

reestablished by measurement (e.g., by NDA or by

weighing, sampling, and analysis). Recommendations

on resolution of indicators (Chapter 10 of this

document) should be used to resolve item

discrepancies.

NUREG/CR-5734 24
7 Shipper-Receiver Comparisons

7.1 Receiving Procedures where

The first action to be taken on receipt of SM and

SNM should be the verification of the number of

items, the item identities, and the integrity of the

tamper-indicating seals. The applicant or licensee

should specify what other checks and measurements

are conducted and when they are conducted after

receipt. The FNMC plan should state, for each

material type, the maximum elapsed time (following

actual receipt) for determining whether or not a

significant SRD exists.

For any SNM received, and also for any received SM

of foreign origin, the licensee must provide all

appropriate information on the DOE/NRC Form 741

that accompanies the shipment. (NOTE: See

NUREG/BR-0006 for instructions and requirements

for completing DOE/NRC Form 741.)

7.2 Determination of Receiver's

Values

For normal and depleted UF6, the licensee may

establish receiver's values by (1) measuring the U-235

isotopic concentration (either by NDA or by sampling

and analysis), (2) weighing each cylinder, and (3) using

a nominal percent uranium factor.

SNM receipts and any SM receipts not in the form of

UF6 should be measured for total quantity, uranium

concentration, and U-235 enrichment.

7.3 Evaluation of Shipper-Receiver

Differences

When shipper's measurement uncertainty (or standard

error) information is available, the following should

define the combined measurement standard error:

combined standard error = [(aS)2 + (P)2] V.

as = shipper's measurement standard error

aR = receiver's measurement standard error

If the shipper's measurement uncertainty values are

not available, the receiver can assume that the

shipper's measurement uncertainty is equal to (but no

greater than) its own uncertainty. In this situation

(i.e., both shipper and receiver have the same

measurement uncertainty), the following becomes the

combined mcasurement standard error:

combined standard error = [2 (aR)2] v. =

1.414 R

The difference between the shipper's value and the

receiver's value (i.e., the SRD), in terms of either

(1) an individual container (for container batches) or a

single batch or lot (when more than one container per

batch), as appropriate, or (2) the total shipment, must

be regarded as significant whenever the SRD exceeds

both 500 grams of U-235 and twice the combined

standard error.

7.4 Resolution of Significant ShipperReceiver Differences

The FNMC plan should describe the steps involved

with the investigation of a significant SRD and discuss

how such difference is resolved. The criteria for

defining a resolved SRD also should be presented.

Generally, resolution of a significant SRD involves a

referee (or umpire) measurement of a retainer

sample(s) but not of the material weight. The

resolution process should specify whose weight value is

used in the resolution process if shipper's and

receiver's weights differ by more than one-half of the

total combined standard error.

25 NUREG/CR-5734
8 Assessment and Review of the Material Control

and Accounting Program

8.1 General Description

The capabilities, pcrformance, and overall effectiveness of the licensee's MC&A program should be

independently reviewed and assessed at least every 24

months. The FNMC plan should describe the

assessment and review program in terms of:

(1) maximum interval between assessments

(2)

1 (3)

selection procedures for the assessment team

number of team members to be selected

(4) qualification and expertise of team members

(5) independence of individual team members from

the MC&A responsibilities and activities they

will be reviewing and assessing

(6) maximum elapsed time and minimum actual

effort to be used for completion of the

assessment and issuance of a final team report

The cntire MC&A program generally should be

reviewed and evaluated during each assessment.

When this occurs, intervals between assessments can

be as much as 24 calendar months. However, if individual assessments only cover part of the MC&A

system, individual subsystems should be assessed at

intervals no greater than 12 calendar months. Thus,

the type of assessment (partial or total) and the

maximum interval between assessments should be

specified. "Interval" means the elapsed time between

either the start of or termination of successive

assessments.

The responsibility and authority for the assessment

program should lie at least one level higher in the

licensee's organizational structure than that of the

MC&A manager. Such responsibility should include

selecting the assessment team leader and initiating

corrective actions. Team members may be selected

from the facility staff or from outside, but an

individual member should not participate in the

assessment of the parts of the MC&A system for

which that person has direct responsibility. Hence,

the MC&A manager may not be a team member.

Also, a given individual should not assess the parts of

the system that are the responsibility of another team

member if the other team member is assessing the

given individual's area. The leader of the assessment

team should have no responsibilities for managing any

of the MC&A elements being assessed.

The minimum number of individuals on any given

assessment should be dependent on the knowledge

and expertise of the team relative to MC&A activities

and their experience in conducting assessments.

Personnel assigned to the assessment team should have

a demonstrated understanding of the objectives and

the requirements of the MC&A program and should

have sufficient knowledge and experience to be able to

judge the adequacy of the parts of the system they

review. The team should have authority to investigate

all aspects of the MC&A system and should be given

access to all necessary information.

To provide a meaningful and timely assessment, the

review and evaluation process'should not be

protracted. The actual review and investigation

activities should be completed in 30 calendar days,

with an additional 15 calendar days allowed for

completing and issuing a final team report.

8.2 Report of Findings and

Recommendations

The areas to be reviewed should encompass the entire

MC&A system, and the level of detail of the reviews

should be sufficient to ensure that the assessment team

has adequate information to make reasoned judgments

of the MC&A system effectiveness. The team report,

as a minimum, should state findings pertaining to:

(1) organizational effectiveness to manage and

execute MC&A activities

(2) management responsiveness to indications of

losses of uranium and possible unauthorized

enrichment activities

(3) staff training and competency to carry out

MC&A functions

(4) reliability and accuracy of accountability

measurements made on SM and SNM

(5) effectiveness of the measurement control

program in monitoring measurement systems

and its sufficiency to meet the requirements for

controlling and estimating both bias and SEID

(6)

(7)

soundness of the material accounting records

effectiveness of the item control program to

track and to provide current knowledge of items

(8) capability to promptly locate items and

effectiveness in doing so

(9) timeliness and effectiveness of SRD evaluations

and resolution of excessive SRDs

27 NUREG/CR-5734
Assessment

(10) soundness and effectiveness of the inventorytaking procedures

(11) capability to confirm the presence of SM and

SNM

(12) capability to detect and resolve indications of

unauthorized enrichment activities, and the

effectiveness of doing so

(13) capability to detect and resolve indications of

missing uranium

On completion of each assessment, the findings and

recommendations for corrective action, if any, should

be documented. The written report should be

distributed to the plant manager, the MC&A manager,

and other managers affected by the assessment.

8.3 Management Review and

Response to Report Findings and

Recommendations

Management should review the assessment report and

take the necessary actions to correct MC&A system

deficiencies. The management review should be

documented within 30 days following the submittal of

the assessment team's report, and it should include a

schedule for the correction of deficiencies. Corrective

actions, if any, that pertain to daily or weekly activities

should be initiated promptly after the submittal of the

final assessment report.

The FNMC plan should address resolution and followup actions associated with concerns identified in the

assessment report. The individuals responsible for

resolving identified concerns, and the timeliness of

such resolution, should be specified.

NUREGICR-5734 28
9 Program for Precluding and Detecting Unauthorized

Production of Enriched Uranium

9.1 Organization

The individual responsible for executing the program

for detecting unauthorized production of enriched

uranium should be identified. This individual need

not be part of the MC&A organization, but should be

independent of the production organization. Other

personnel who are assigned responsibilities in this

program also should be independent of production

supervision. This program should be well coordinated

with both MC&A and production'management..

The overall organization, including the minimum

staffing requirements and functions, should be in the

FNMC plan. A definitive statement should be made

that the program director will have the necessary

authority to carry out all aspects of the program.

9.2 General Description of Program

Alternative approaches are available to detect

unauthorized production of enriched uranium. The

overall design of this program should include an

analysis of potentially credible means by which

unauthorized production could occur. That is, for

each conccivable and credible scenario for

unauthorized production, a surveillance or an

enrichment monitoring system for the timely detection

of that scenario should exist. The' analysis should be

extensive and conducted by individuals having a

thorough knowledge of the processing equipment and

enrichment technology. All conceptual and credible

scenarios for unauthorized production of uranium

enriched to 10wt % or more in U-235 by the'

employed enrichment technology should be identified.

These scenarios should include cascade isolation,

process system adjustments, batch recycle processing,

cascade interconnections, and cascade reconfiguration

(to increase the number of stages).

The program should be capable of satisfying the

following detection criteria:

(1) For any unauthorized production (from

undeclared feed) of LEU with an enrichment of

less 'than 10 wt'% U-235, detection'should occur

before the quantity of U-235 contained in such

LEU amounts to '25 kilograms.

(2) For any unauthorized'production of LEU with

an enrichment within the range of 10.00 to

19.99 wt % U-235, detection must occur before

the quantity of U-235 contained in such LEU

amounts to 10 kilograms.

(3) For any unauthorized production of highenriched uranium (HEU, i.e., 220% U-235),

detection must occur before the quantity of U235 contained in such HEU amounts to 1

kilogram.

The FNMC plan should address the following aspects

of the program that are aimed at protecting against

and detecting unauthorized production of uranium of

low strategic significance:

(1) the type of surveillance, and its frequency, to be

applied to the processing areas

(2) the type of surveillance, and its frequency, to be

applied to the process control room and other

areas where operation of processing equipment

can be controlled or modified

(3) the type of surveillance, and its frequency, to be

applied to potential feed and withdrawal areas

(4) process monitoring activities (e.g., radiation

monitoring and flow metering), other than

process sampling, that could contribute to the

detection of unauthorized production

(5) use of tamper-indicating seals on process valves

and flanges

(6) personnel access controls that limit the number

of individuals who could gain access to the

enrichment processing equipment or its control

mechanisms

(7) physical security controls such as locked and

* alarmed doors, closed-circuit television monitors,

tc., that would detect unauthorized access to

processing equipment or product material

(8) production control activities that could

contribute to the detection of unauthorized

production

(9) employee education and informant protection

(e.g., whistle-blower protection rules) to increase

the probability of detection and reporting of

potential unauthorized activities by.facility

personnel

(10) notification of appropriate MC&A personnel by

operations organizations of the operating status

of the enrichment process system, especially

when a cascade is isolated from the process

stream

29 NUREG/CR-5734
Detecting Unauthorized Production

To address the unauthorized production of uranium

enriched to 10 wt % or more U-235, the following

types of measures should be considered:

(1) process design features that preclude production

of higher enrichments from being conducted

simultaneously with normal (i.e., authorized)

production

(2) personnel access controls that limit the number

of individuals who could gain access to the

enrichment processing equipment or its control

mechanisms

(3) physical security controls such as locked and - alarmed doors, closed-circuit television

monitors, etc., that would detect unauthorized

access to processing equipment or product

material

(4) process control systems that could detect

unauthorized use of production equipment

(5) production control systems that could detect

unauthorized production of 2 10 wt % U-235

(6) technical safeguards systems (e.g., optical

surveillance, tamper-indicating seals, radiation

monitors, flow meters, and visual inspection

procedures) that could detect unauthorized

ploduction of enriched uranium

(7) nuclear material, minor isotope, and separative

work unit (SWU) balances

In describing the portion of the program aimed at

protecting against and detecting production of

uranium enriched to or greater than 10 wt % U-235,

the FNMC plan should address the following, in

addition to the previously stated aspects for detecting

unauthorized production:

(1) location of the sampling ports, and frequency of

sampling, to be used for monitoring product

streams

(2) the means for verifying the validity of process

(3)

control measurements and laboratory

enrichment measurements (i.e., how would

falsification of process measurements be

detected?)

the type of equipment or instrumentation (in

addition to and independent from that used and

controlled by production personnel) to be used

for monitoring purposes

9.3 Data, Information, and Activities

to be Monitored

The specific data, information, and activities to be

monitored should be identified. The frequency of each

specified monitoring activity and frequency of data

evaluation should be addressed.

The means for independently assessing the authorized

process enrichment parameters needs to be shown. To

accomplish this, the program should address

verification of the following:

(1) weighing, sampling, and isotopic assay of

material introduced at the feed station(s)

(2) weighing, sampling, and isotopic assay of

material withdrawn at the product and tails

withdrawal stations

(3) sampling and isotopic assay of in-process

material at randomly selected points

(4) consistency of the quantity of U-235 determined

to be in the product and tails with the quantity

in feed

(5) determination of the SWU balance

For gaseous diffusion and gas centrifuge facilities, the

licensee or applicant should consider monitoring

process parameters such as UF6 gas pressures, flow

rates, enrichments, valve positions, cascade configuration and connections, and tracking of all potential UF6

containers in the process area. Verification of

measurements also can be obtained by independent

observations of measurement processes and by using

NDA techniques to verify isotopic ratios and contents

of containers. The purpose is to ensure that the

facility has not been, and is not being, misused.

The overall design of the program should include

analyses on all processing and product streams to

determine where uranium isotopic measurements

should be made and at what frequency they should be

performed to preclude clandestine enrichment

activities. That is, for each credible scenario for

clandestine enrichment, a monitoring system for the

timely detection of any implementation of that

scenario should be implemented. Because the activity

of most interest is whether unauthorized HEU is being

produced, NDA measurement techniques for

enrichment may be very practical. Either manual

measurements using portable NDA instruments can be

used or the instruments can be permanently affrxed to

the process equipment. In the former case,

administrative controls should be used to prevent

collusion of the measurement personnel with a

NUREG/CR-5734 30
Detecting Unauthorized Production

potential clandestine perpetrator. In the latter case,

frequent inspection and testing of the instruments

should be performed to prevent tampering or

disabling of the NDA measurement system.

The scenario analysis performed should address each

product stream regardless of material type or

composition and be conducted by individuals having a

thorough knowledge of the processing equipment and

enrichment technology. Credible means for producing

uranium at enrichment levels equal to or greater than

10 wt % U-235 should be identified. These

approaches should include process system adjustments,

batch recycle processing, cascade interconnections, and

cascade reconfiguration (e.g., to increase the number

of stages).

The extensiveness and complexity of the monitoring

program should be dependent on such factors as:

(1) the minimum time required to produce HEU

containing 1 kilogram of U-235

(2) process design features that would preclude

unauthorized enrichment from being conducted

simultaneously with normal, authorized

enrichment

(3) personnel access controls that limit the number

of individuals who could gain access to the

enrichment processing equipment or its control

mechanisms

(4) physical security controls such as locked and

alarmed doors, closed-circuit television

monitors, etc., that would detect unauthorized

access to enrichment equipment, feed or

product material, or the enrichment production

area

(5) process control systems that would detect

unauthorized use of enrichment equipment

The FNMC plan should address such aspects as:

(1) type and frequency of uranium isotopic

measurements

(2) type and frequency of NDA monitoring

measurements

(3) required accuracy of the isotopic measurements

(4) administrative controls to be applied to all

monitoring measurements

The means for independently verifying the authorized

process enrichment parameters given in this section

should be shown. The specific data, which will be

collected and analyzed, should be identified. The

frequency of the measurements and of data evaluations

should be stated.

Some examples of technical measures that could satisfy

the licensee's responsibility for addressing

unauthorized production and for providing auditability

of the conclusion that unauthorized production has

not occurred are identified as follows for the three

leading enrichment technologies:

Centrifue - The installation of supplemental

materials verification techniques such as NDA

measurements, process and cylinder sampling, flow

measurements, cylinder weighings, and item

verification will assist in detecting missing material or

out-of-balance conditions. Instrumentation used for

these techniques could be tamper-indicating, and

additional containment and surveillance techniques

could provide evidence of both unreported cascade

reconfiguration and suspect feed or withdrawal in the

cascade hall. Potential containment and surveillance

techniques include radiation measurement and

surveillance instrumentation such as personnel and

vehicle portal monitors, package monitors, perimeter

barrier sensor systems, optical surveillance

instrumentation, and tamper-indicating seals.

Gaseous Diffusion - The installation of in-line

enrichment monitors and gas flow meters at the

product withdrawal points could address most

unauthorized production scenarios. Materials

accounting techniques could be supplemented by

containment and surveillance techniques such as

radiation measurement and surveillance

instrumentation for personnel, packages, and vehicles;

perimeter barrier sensor systems; optical surveillance

instrumentation; and tamper-indicating seals to assist

in addressing theft scenarios.

Laser sotope Separation - Examples will need to be

developed upon completion of commercial designs.

9.4 Reporting and Documentation

Requirements

The applicant or licensee should make a definitive

statement defining the basis for declaring that (1)

unauthorized production of enrichment has taken

place, and (2) unauthorized production of uranium of

low strategic significance has taken place. Whenever

systems indicate that unauthorized production of

uranium enrichment may have occurred or may be

31 NUREG/CR-5734
Detecting Unauthorized Production

occurring, that determination becomes an indicator'

that should be subject to the investigation and

resolution requirements of 10 CFR 74.33(c)(5). If

actual unauthorized production of enriched uranium is

discovered, that discovery must be reported to the

NRC within 1 hour as required by 10 CFR 74.11.

NUREGICR-5734 32
10 Resolving Indications of Missing Uranium and of Unauthorized

Production of Enriched Uranium

10.1 Methods and Procedures for

Identifying Indicators

The FNMC plan should discuss the means by which

the licensee will resolve indicators of (1) missing

uranium involving 500 grams or more of U-235 or (2)

unauthorized production. The three generic types of

indicators are as follows:

(1) indications that SM or SNM is missing

(2) indications that the enrichment equipment has

been or is being used to produce undeclared

uranium enriched to less than 10 wt % for

unauthorized use or distribution

(3) indications that the enrichment cquipment has

been or is being used to produce uranium

enriched to 10 wt % or more in U-235

The licensee's resolution program should address the

possible indicators of missing uranium. The FNMC

plan should enumerate all the potential indicators that

can be postulated for indicator types 1 through 3

above and develop resolution procedures for each.

The following are examples of possible indicators of

missing uranium:

(1) lack of agreement of dynamic or static

inventories with the MC&A records

(2) determination through the item control

program that a specific item is not in its

authorized location and its actual location is

not immediately known

(3) discovery that an item's integrity or its

tamper-indicating seal was compromised

(4) information from the process control system

indicating potential loss of material from the

process system (e.g., improper valve settings)

(5) an allegation of theft or diversion

Examples of possible indicators of unauthorized

production of uranium enriched to less than 10 wt %

U-235 are:

(1) presence of unauthorized product, feed or tails

cylinders

(2) SWU imbalances (e.g., reduced production

capacity)

(3) presence of tails at enrichments lower than the

design range

(4) presence of excess mass or amount of tails, or

other ID

(5) discovery of records tampering

(6) discovery of unauthorized feed or withdrawal

equipment or reset valve configurations to

permit feeding and withdrawal

(7) unauthorized operational activities in the

enrichment process facilities

(8) receipt of allegations

Examples of possible indicators of unauthorized

production of uranium enriched to 10 wt % or greater

in U-235 are:

(1) any of the preceding items

(2) any measurement from a stream monitoring

program that indicates out-of-specification

enrichment concenitrations for any feed,

product, or tails stream

(3) unauthorized reconfiguration, isolation, or

' interconnection of enrichment equipment, or

changes in valve settings

(4) equipment used for monitoring enrichment

levels in product streams not functioning -properly or compromised

(5) an allegation that unauthorized production of

uranium enriched to 10 wt % or more in U-235

has occurred or is'under way

(6) radiation signatures or background radiation

levels greater than normally expected

10.2 System and Procedures for

Investigating and Resolving

Indicators

At least one major MC&A procedure should address

the system and procedures for investigating and

resolving indicators because this topic pertains to three

of the performance objectives of 10 CFR 74.33(a).

Thus, the licensee should have well-defined procedures

for investigating indicators of both (1) possible missing

uranium (involving 500 grams or more of U-235), and

(2) possible unauthorized production activities.

33 NUREGICR-5734
Resolving Indicators

Likewise, there should be established criteria for

defining what constitutes resolution of an investigated

indicator.

Resolution of an indicator means that the licensee has

made a determination that loss, theft, or unauthorized

production of uranium has not occurred and is not

occurring. For each type of indicator, the licensee

should develop detailed'resolution procedures and

should describe or outline them in the FNMC plan.

Any investigation of an indication of a loss or

unauthorized production should provide, whenever

possible, (1) an estimate of the quantity of SM and/or

SNM involved, (2) the material type or physical form

of the material, (3) the type of unauthorized activity

detected, (4) the time frame within which the loss or

activity could have occurred, (5) the most probable

cause(s), and (6) recommendations for precluding

reoccurrence.

In the case of indicators that loss or theft of more

than 500 grams of U-235 may have occurred, the

resolution process should include (1) thoroughly

checking the accountability records and source

information, (2) locating the source of the problem,

(3) isolating the exact reason for the problem within

the area or processing unit, (4) determining the

amounts of SNM or SM involved,'and (5) making a

determination that the indication is or is not resolved.

The resolution procedures should be prepared in such

a manner that no individual that could have been

responsible for the potential' loss also would be

responsible for its resolution. If an investigation of an

indicator results in a conclusion that the indication is

true, such conclusion must be reported to the NRC

within 1 hour of its determination pursuant to 10

CFR 74.11. The FNMC plan should show the

reasonable time allowed for resolution. In general, a

time not exceeding 72 hours should be adequate.

In the case of indicators of unauthorized production

of uranium enriched to less than 10 wt % U-235, the

licensee should verify that the indicator is true,

determine its cause, and conclude if unauthorized

production has occurred or is occurring. If an

investigation of an indicator results in a conclusion

that the indication is true, such conclusion must be

reported to the NRC within 1 hour of its

determination pursuant to 10 CFR 74.11. The FNMC

plan should show the reasonable time allowed for

resolution. In general, 72 hours should be adequate.

:~~~~~~~~~~~~~~~~~~~~~

In the case of indicators of unauthorized productions

of enrichments of 10 wt % or greater in U-235, the

resolution process should include investigation of all

the information that contributed to the indication of

such unauthorized production. On receipt of an

indication that uranium enriched to 10 wt % or more

has been discovered, the licensee should immediately

isolate the process area or storage area from which the

indication came to verify the indication. The

instruments and measurement systems used for

monitoring should be examined to determine if they

are functioning properly. A thorough examination of

the processing equipment should be performed to

ensure that unauthorized modifications were not made.

The presence of uranium enriched to 10 wt % or more

in U-235 should be verified through remeasuring the

material in question whether in item form or in

process equipment. If this investigation determines

that an indication of unauthorized production of

enrichments of 10 wt % or more in U-235 is true, this

condition is reportable pursuant to 10 CFR 74.11.

The FNMC plan should show the reasonable time

allowed for resolution. In general, 72 hours should be

adequate.

If the investigation conducted to resolve the indication

does not observe the production of uranium enriched

to 10 wt % or more in U-235, further measures are

needed before the licensee may conclude that the

indicator is fully resolved. To protect against the

relocation and concealment of the enriched uranium, a

thorough investigation of the entire facility should be

performed by individuals who are independent of the

processing organization.

10.3 Response Actions for Unresolved

Indicators

Response actions to unresolved indicators should be

clearly defined and should be on a graded scale

appropriate to the level of potential safeguards

significance. The responsibility and authority for

initiating and executing response actions also should

be defined.

For indicators of missing uranium, the level of

safeguards concern is related to such factors as:

(1) whether the potential missing uranium is

depleted, natural, or enriched

(2) the potential quantity of U-235 involved

(3) the material attractiveness (from the standpoint

of its potential use in a nuclear explosive

device) of the potential missing uranium

relative to its composition or form (i.e., U

metal, U308, uranyl nitrate solution, UF6, scrap,

or waste)

At LEU enrichment facilities, indicators of

unauthorized production of uranium enrichment

generally have a higher level of safeguards concern

than indicators of missing uranium. The degree of

NUREG/CR-5734 34
Resolving Indicators

concern for unauthorized production indicators is

related to such factors as:

(1) whether the indicator pertains to unauthorized

production in the planning stage, currently in

progress, or already accomplished

(2) whether the potentially produced material is

low strategic SNM, moderately strategic SNM,

or strategic SNM

(3) the potential quantity of unauthorized material

already produced

10.4 Documentation Requirements

The FNMC plan should identify all documentation

requirements associated with the licensee's program

for the reporting, investigation, and resolution of

missing uranium indicators and of unauthorized

production indicators. Review and approval

requirements and document custodial responsibility

also should be defined. As a minimum, documentation

of the following should be included:

(1) investigation procedures

(2) resolution procedures

(3) reporting of indicator to MC&A management

including date and time the indicator was

reported, name of individual who discovered the

indicator, and description of indication

(4) investigation findings and conclusion, including

resolution status, date issued, name and

signature of principal investigator, and approval

signature of MC&A manager

(5) reports made to NRC for unresolved indicators

and for indicators determined to be real,

including date and time the report was made,

method of communication, and name of NRC

individual contacted

35 NUREG/CR-5734
11 Informational Aid for Assisting in the Investigation and

Recovery of Missing Uranium or Assisting in the

Investigation of Unauthorized Enrichment

When an investigation relating to actual (or highly

suspected) events pertaining to missing uranium or

unauthorized enrichment is conducted by the NRC

and/or other government agencies, the licensee is to

have ready for and to provide to the investigators any

information deemed relevant to (1) the recovery of

material involved in a loss, theft, or diversion and (2)

unauthorized production of uranium enrichment. The

burden shall be on the licensee to provide (without

being asked to) all information that it recognizes as

being relevant, as opposed to only providing

information that the investigators are knowledgeable

enough -to ask for. This information would include

production records, accountability data, and routinely

prepared reports. Kinds of information that may aid

the investigation are:

(1) data or observations that led the operator to

determine that a loss or theft of uranium or

unauthorized production may have occurred

(2) data, observations, and assessments associated

with attempts to resolve the indication of

missing material or unauthorized production

Information indicating that a loss of uranium may

have occurred are those provided by physical

inventories, the item control program, and shipperreceiver comparisons (Chapters 5, 6, and 7,

respectively). This information could include:

(1) material accountability data records and reports

(2) inventory records

(3) inventory difference and propagation of error

calculations

(4) inventory reconciliation reports

(5) indications of unrecorded or unauthorized

removals of SM or SNM from storage or

process locations

(6) reports of apparent destruction or falsification

of records of an items existence

(7) records of broken tamper-indicating devices or

compromised item integrity

(8) indications of unauthorized entry into SM and

SNM storage areas

(9) Reports from monthly item status inspections

(10) material receipt and log-in records

(11) results from shipper-receiver difference

evaluations

(12) process monitoring and control records

Information indicating that unauthorized production

may have occurred are those provided by the program

for precluding and detecting unauthorized production

(Chapter 9). This information could include:

(1) reports assessing potentially credible means for

unauthorized enrichment

(2) -indications of unauthorized activities in

enrichment process areas

(3) indications of anomalous process configurations

(4) indications of anomalous process conditions

(5) indications of unauthorized entry into the

enrichment process areas

(6) indications of anomalous enrichment levels

(e.g., process sample or radiation measurement

data)

(7) indications of anomalous feed, product, or tails

quantities

(8) indications of unauthorized feed or withdrawal

locations and/or containers

(9) anomalous production data (e.g., SWU

imbalances)

Information associated with resolving indications of

missing uranium and of unauthorized production are

provided in Chapter 10. This information would

include:

(1) the type of unauthorized activity detected

(2) the interval during which the loss or

unauthorized production may have occurred

(3) the amount of material and form of the

material involved in the loss

(4) estimates of the extent of unauthorized

production

(5) results of measures to validate indicators

(6) results of extended measures to resolve

indicators

37 NUREG/CR-5734
Assisting Investigations

(7) results from special inventories (or

reinventories) and tests performed

(8) audit results of the SM and SNM accountability

source data

(9) assessments of measurement data and

measurement controls

(10) results from reviews of the material control and

accounting program and status of corrective

actions

(11) history of indicator investigation and resolution

activities

(12) indicator investigation and resolution

procedures and conclusions

(13) probable cause of the loss

(14) any abnormal events that may have contributed

to or caused the loss

(15) the names of the people who could have been

responsible for the loss

Much of the backup information necessary to assist in

an investigation would be records maintained in the

facility records system described in Chapter 12.

NUREG/CR-5734 38
12 Recordkeeping

12.1 Description of Records

The FNMC plan should identify all records, forms,

reports, and standard operating procedures that must

be retained for a minimum of 3 years, as required by

10 CFR 74.33(d). Such records should include, but

are not limited to, the following:

(1) documents that define changes in the MC&A

management structure or changes in

responsibilities relating to MC&A positions;

(2) procedures pertaining to any accountability or

10 CFR 74.33(c)(5) related measurement or

sampling operation

(3) forms used to record or to report measurement

data and measurement results, including source

data

(4) forms and notebooks used to record calibration

data associated with any accountability

measurement system

(5) forms and notebooks used to record quantities,

volumes, and other data associated with the

preparation of standards, both calibration and

control, used in connection with accountability

measurement systems

(6) forms and official memos used to record or

report measurement control program data,

control limit calculations, and out-of-control

investigations

(7) forms listings and instructions associated with a

physical inventory, both dynamic and static

(8) forms and formal worksheets used in the

calculation of SEID, ID, and active inventory

values

(9) ledgers, journals, and computer printout sheets

associated with the accountability system

(10) ledgers, journals, and computer printout sheets

associated with the item control program,

including seal usage and "attesting to" records

(11) DOE/NRC forms 741 and 742

(12) forms, memos, and reports associated with

identification of, investigation of, and

resolution of significant SRDs

(13) loss indication and alleged theft investigation

reports

(14) investigation reports pertaining to indications of

activities related to unauthorized production of

enriched uranium

(15) investigation reports pertaining to excessive IDs

(16) official reports containing the findings and

recommendations of MC&A system assessments

and any letters or memos pertaining to response

actions to assessment team recommendations

(17) forms used for recording data associated with

the monitoring program

(18) monitoring program status or summary reports

(19) records of training sessions including date given,

topics covered, name of instructor(s), names

and signatures of those attending

(20) training, qualification, and requalification

reports and records

Examples of the more important MC&A forms should

be provided in the FNMC plan annex or appendix.

The retained records and reports should contain

sufficient detail to enable NRC inspectors to

determine that the licensee has implemented system

features and capabilities of 10 CFR 74.33(c) and has

met the general performance objectives of 10 CFR

74.33(a).

12.2 Program and Controls for

Ensuring an Accurate and

Reliable Record System

The FNMC plan should describe the controls used to

ensure that records are highly accurate and reliable.

The record system also should provide a capability for

easy traceability of all SM and SNM transactions from

source data to final accounting records.

The following topics should be addressed:

(1) the auditing system or program to verify the

correctness and completeness of records

(2) the overchecks for preventing or detecting

missing or falsified data and records

(3) the plan for reconstructing lost or destroyed SM

and SNM records

(4) the access controls used to ensure that only

authorized persons can update and correct

records

39 NUREG/CR-5734
Recordkeeping

(5) the protection and redundance of the record

system such that any act of record alteration or

destruction will not eliminate the ability to

provide a complete and correct set of SM and SNM

control and accounting information needed to achieve

the perfornance objectives of 10 CFR 74.33(a)

NUREG/CR-5734 40
Glossary

The following terms are defined in the context of (1)

their usage in this document and/or (2) how they.

should be used if contained in the fundamental

nuclear matcrial control (FNMC) plans submitted

pursuant to 10 CFR 74.33(b).

ACCOUNTABILITY - The 'detarmination of, and

current record maintenance of, source material (SM)

and special nuclear material (SNM) quantities associated with (1) receipts, (2) shipments, (3) measured

discards, (4) transfers into or between material

balance areas (MBAs) and/or item control areas

(ICAs), and (5) total material on current inventory.

ACCOUNTANCY (ACCOUNTING) - The records

(c.g., ledgers, journals, sourcc documents, etc.)

associated with accountability.

ACrIVE INVENTORY -The sum of beginning

inventory (BI), additions to inventory (A), removals

from inventory (R), and ending inventory (El) after all

common terms have been totally excluded. A

common term is any SM or SNM matcrial value (or

item) that appears in both BI and EI, or both BI and

R, or both A and R, or both A and El, with both

values derived from the same measurement (and thus,

does not contribute to the uncertainty associated with

the current period inventory difference). The active

inventory is used as an indicator of processing

throughput and/or processing activity. 

ADDITIONS TO INVENTORY - Quantities of SM

and SNM materials received by a plantw and which,

prior to such receipt, was not part of the plant's total

possessed SM or SNM quantity.

ARTIFACT STANDARD -A container or item, of

certified mass, having a size, shape, and mass that is

representative of a particular type of process-related

item or container (e.g., a UF6 cylinder). Weighing

error caused by buoyancy is eliminated by the use of

artifact standards for scale calibrations.

ASSIGNED VALUE - A value for mass, volume,- SM

or SNM concentration, SM or SNM quantity, etc.,.

assigned to a standard weight, standard material, etc.,

used for calibrating and/or controlling a measurement

device or system. An assigned value may not

necessarily be a certified value, but, nevertheless, it is

the best estimate of the standard's true value.

AUDITABILITY -The availability of evidence to

U.S. Nuclear Regulatory Commission (NRC)

inspectors demonstrating the validity of a licensee's

conclusion that unauthorized production has not

taken place.

AUTHORIZED LEVELS - The maximum uranium

enrichment level [i.e., weight percent (wt %) U-2351

and the maximum quantity of U-235 (contained in

enriched uranium) -that can be possessed as specified

by an issued NRC license.

BEGINNING INVENTORY - For each material type

code, the total itemized quantity of SM or SNM

possessed by a facility at the start of a material balance

period (i.e., inventory period). The beginning

inventory quantity for any given material balance

period is (by definition) exactly equal to the ending

inventory quantity for the immediately previous period.

BIAS (MEASUREMENT BIAS) - A constant, -

unidirectional component of error that affects all

members of a measurement data set. Thus, a bias can

be estimated from the deviation of the mean of several

measurements of a representative standard from the

reference value (or assigned value) of such standard.

CALIBRATION - The process of determining the

numerical relationship between the observed output of

a measurement system and!thc actual value 6f the

characteristic being measured, as based on primary or

reference standards.

CERTIFIED STANDARD - A standard weight,

material, device, or instrument having an assigned

value that is guaranteed to be within specified limits by

a nationally or internationally recognized organization

(e.g., bureau, laboratory, etc.) that issues and/or

certifies standards.

CHECK STANDARD (BENCH STANDARD,

WORKING STANDARD) -A standard, not

necessarily traceable to a primary standard, that is used

routinely (e.g., daily or weekly) to check (or verify) the

reliability of a measurement device, instrument, etc.

(including those of accountability measurement

systems). Such standards are not, however, used, for

the actual calibration or control of accountability

measurement systems.

COMBINED STANDARD ERROR -An error band

derived from the respective standard error values

associated with each of two measurements (usually

independent of each other) performed on a given 

material quantity. For both measurement values (of

the pair) to be regarded as being in agreement, they

must not differ from each other by more than the

calculated combined standard error, which is normally

calculated by taking the square root of.the sum of

squared individual standard errors.; That is:

combined S.E. = [(ai)2 + (cf)2] 1 

CONTROL STANDARD -,A standard that (1) is

representative of the process material being measured

and (2) is itself measured periodically to monitor for

41 41NUREG/CR-5734
Glossary

and to estimate any bias associated with the

measurements of the process material in question.

A control standard must be traceable to a primary or

reference standard.

CUSTODIAN - A designated individual who is

responsible for (1) the control and movement of all

SM and SNM within a specified control area, and

(2) maintaining records relative to all SM and SNM

that is transferred into or out of the area and that is

currently located within the control area. Control

areas are usually designated as MBAs or ICAs. From

the standpoint of good safeguards practice, a single

individual should not be a custodian of more than one

control area.

DEPLETED URANIUM - Any uranium-bearing

material whose combined U-233 plus U-235 isotopic

content is less than 0.70 wt % (relative to total

uranium elemental content).

DETECTION QUANTITY (DQ) - A site-specific

U-235 quantity in SM or SNM for licensees whose

processing activities are limited to SNM of low

strategic significance. The DQ is normally a function

of annual throughput, but for low-throughput lowenriched uranium (LEU) facilities, the DQ need not

be less than 25 kilograms of U-235. The DQ also can

be described as a goal quantity, the loss or theft of

which must be detected with a 90 percent (or better)

probability at the time of a physical inventory.

DETECTION THRESHOLD (DT) -An inventory

difference (ID) limit that will be exceeded (with

90 percent or higher probability) by an ID resulting

from the taking of a physical inventory whenever there

has been an actual loss of a detection quantity. The

DT is a function of both the DQ and the standard

error of the inventory difference (SEID), as shown by

the following equation:

DT = DQ - 1.3 (SEID)

EFFECTIVE KILOGRAM - An effective kilogram

of SNM means (I) for plutonium and U-233, their

weight in kilograms; (2) for uranium with an

cnrichment in the isotope U-235 of 1.00 wt % (i.e.,

0.01'g U-235/g U) and ab6ve, its element weight in

kilograms' multiplied by the square of its enrichment

expressed as a decimal weight fraction; and (3) for

uranium with an enrichment in U-235 below 1.00

wt %, but above 0.71 wt %, its element weight in kilograms multiplied by 0.0001.

ENDING INVENTORY - For each material type

code, the total itemized quantity of SM or SNM

possessed by a facility at the end of a material balance

period, as determined by a physical inventory. The

ending inventory quantity for any given material

balance period is (by definition) exactly equal to the

beginning inventory quantity for the next period.

ENRICHED URANIUM -Any uranium-bearing

material that does not qualify as natural uranium and

whose combined U-233 plus U-235 isotopic content is

0.72 wt % or higher relative to total uranium

elemental content.

FORMULA KILOGRAM (FKG)- The number of

formula kilograms is computed by the following

equation:

FKG = (grams U-235 contained in high-enriched

uranium) + 2.5 (grams U-233 + plutonium)

1000 grams

FORMULA QUANTITY - Strategic SNM in any

combination in a quantity of 5.00 FKGs or more.

HIGH-ENRICHED URANIUM (HEU) - Any

uranium-bearing material whose U-235 isotopic

content is 20.00 wt % or more relative to total

uranium elemental content.

INVENTORY DIFFERENCE (ID) -The arithmetic

difference between a book inventory and the

corresponding physical inventory, calculated by subtracting ending inventory (El) plus removals from

inventory (R) from beginning inventory (BI) plus

additions to inventory (A). Mathematically, this can

be expressed as:

ID = (BI + A) - (El + R)

INVENTORY RECONCILIATION -The adjustment

of the book record quantity of both element and fissile

isotopes to reflect the results of a physical inventory.

In the broad sense, inventory reconciliation also

includes the activities of calculating (1) the ID for the

material balance period in question, (2) the - uncertainty (i.e., SEID) value associated with the ID,

(3) the active inventory for the period; and (4) any bias

adjustment and/or prior period adjustment associated

with the ID value.

ITEM - Any discrete quantity or container of SM or

SNM, not undergoing processing, having a unique

identity and also having assigned uranium and U-235

quantities.

ITEM CONTROL AREA (ICA) - An identifiable

physical area for the storage and control of SM and

SNM items. Control of items moving into or out of

an ICA is by item identity and SM and SNM quantity

as determined from previous measurement.

NUREG/CR-5734 42
Glossary

ITEM CONTROL PROGRAM - A system that

tracks (i.e., records) the creation, identity, location,

and disposition of all SM and SNM items of certain

predetermined item categories. In addition, item

control programs usually provide a periodic ' verification of item existence and location for static

items.

LOW-ENRICHED URANIUM (LEU) -Any

uranium-bearing material whose U-235 isotopic

content is greater than 0.72 wt % but less than 20.00

wt % relative to total uranium elemental content.

MATERIAL BALANCE -A comparison on a

measured basis of beginning inventory plus additions

to inventory to ending inventory plus removals from

inventory for a given control area (or combination of

control areas) over a specified period of time.

MATERIAL BALANCE AREA (MBA) - An

identifiable physical area for the physical and

administrative control of nuclear material such that

the quantity of nuclear material being moved into or

out of the MBA is represented by a measured value

(for both element and isotope).

MATERIAL BALANCE PERIOD -The time span

to which a material balance or physical inventory

pertains.

MATERIAL TYPE CODES - Number codes for

identifying basic material types with respect to SM,

SNM, and by-product materials. These codes are used

by the Nuclear Materials Management and Safeguards

System (NMMSS) for tracking U.S.-owned and U.S.-

possessed materials worldwide. For SM and SNM,

eight material type codes have been assigned as

follows:

CODE MATERIAL TYPE

. 10 ; Depleted Uranium

20 Enriched Uranium (*)

50 Plutonium

I 70 Uranium-233 ("")

CODE

81 - 83

88

89

MATERIAL TYPE

Normal Uranium

Plutonium-238 ("')

norium

Uranium in Cascades

*For DOE/NRC Form 742, material code 20 has 4 subcodes

to denote enrichment range: El, E2, E3, and E4. For NRC Form

327, material code 20 has 2 subcodes: LEU and lIEU.

*'Uranium materials should be regarded as material code 70

if the U-233 isotopic abundance is greater than (1) 10.00 wt %

relative to total uranium elemental content or (2) both (a) the U233 isotopic abundance is greater than the U-235 isotopic

abundance and (b) the U-233 isotopic abundance exceeds 5.00 wt %

relative to total elemental uranium content; otherwise report as material code 10, 20, or 81, as appropriate. 

"Plutonium materials should be regarded as material code

83 if the plutonium-238 isotopic abundance is greater than 10.00 wt

% relative to total plutonium elemental content; otherwise, report as material code 50.

MEASURED DISCARD - A batch or quantity of

waste, whose SM or SNM content has been

determined by measurement, that (1) has been shipped

to a disposal site, released to the environment, or

stored on site, and (2) has been taken off the

accounting ledgers as part of the current inventory of

possessed SM and SNM.

MEASUREMENT -The process of determining a (1)

uranium elemental concentration, (2) specific uranium

isotopic content, (3) U-235 enrichment (i.e., isotopic

abundance), (4) bulk material mass or item mass, or

(5) bulk material volume. Measurement values are

derived through a calibration process that establishes

the relationship between instrument (i.e., device)

response and the parameter being determined.

MEASUREMENT CONTROL PROGRAM - A

managed program for monitoring and controlling both

accuracy and precision of SM and SNM accountability

measurements.

NATURAL URANIUM - Any uranium-bearing

material whose''uranium isotopic distribution has not

been altered from its naturally occurring state.

Natural uranium is nominally 99.283 wt % U-238,

0.711 wt % U-235,' and 0.006 wt % U-234.

NORMAL URANIUM - Any uranium-bearing

material having a uranium isotopic distribution that

can be characterized as being (1)'0.700 wt % to 0.724

wt % in combin'ed U-233 plus U-235 and (2) at least

99.200 wt % in U-238. (NOTE: All natural uranium

having a U-235 isotopic abundance in the range of

0.700 wt % to 0.724 wt % is normal uranium, but not

all normal uranium is natural uranium.)

PHYSICAL INVENTORY -A determination by

physical means (visual and measurement) of the

quantity of SM'or SNM on hand for a given material

type code at a specified point in time. The primary

purpose for a physical'inventory is to confirm the

absence of (or to detect) a loss, theft, or diversion of

SM or SNM. For the conclusion drawn from a

physical inventory to be meaningful, not only does the

physical presence of all material (or at least the vast

majority of the material) need to be confirmed, but the

quantities of material in the inventory also need to be

remeasured, or other assurance provided, to verify that

prior measurements are still valid. Physical inventories

are to be conducted on a "plant" as well as on a

"material type code" basis.

PLANT -For SM and SNM control and accounting

purposes, a plant-is defined as a set of processes or

operations (on the same site, but not necessarily all in

the same building) coordinated into a single

43 NUREG/CR-5734
Glossary

manufacturing, research and development, or testing

effort. Most licensees have only one plant in this

context. Independent on-site manufacturing efforts,

such as a scrap recovery operation serving both on-site

and off-site customers, should be treated as separate

plants.

POINT-CALIBRATED MEASUREMENT

SYSTEM - A measurement system in which the

measurement value assigned to an unknown measured

by the system is derived from the response obtained

from the measurement of a representative calibration

standard(s) that was measured along with (i.e., at the

same time as) the unknown. The standard(s) must

undergo all the measurement steps (e.g., aliquoting,

sample pretreatment, etc.), and in the same manner,

as the unknown. Point-calibrated measurement

systems can be regarded as bias free, provided that

adequate controls are in place to ensure the validity of

the standard's assigned value.

PRIMARY STANDARD - Any device or matcrial

having a characteristic or parameter (such as mass,

uranium concentration, uranium isotopic distribution,

etc.) whose value is certified (within a specified

uncertainty) by a nationally or internationally

recognized bureau, laboratory, etc., that issues and/or

certifies standards.

PRIOR PERIOD ADJUSTMENT - Any correction

(i.e., adjustment) to an ID value because of a

correction applied to a component of beginning

inventory after the inventory period started. Such corrections may be because of resolution of a shipperreceiver difference (SRD) on material received during

a prior inventory period, correction of a recording

error, etc. Because these types of corrections have

nothing to do with current period losses or errors, and

because the official beginning inventory value is not

adjusted, an adjustment to the ID value (derived from

the ID equation) is necessary to obtain an ID that

reflects only current period activity.

PROCESS MONITORING - A system of monitoring

production data (e.g., flow rates, yields, densities, etc.)

and- of production control or quality control

measurements (as opposed to accountability

measurements) that could provide early (i.e., timely)

detection of an anomaly that may indicate a significant

loss or theft of SM or SNM or indicate unauthorized

enrichment activities.

RANDOM ERROR - The variation encountered in

all measurement work, characterized by the random

occurrence of both positive and negative deviations

from a mean value.

RECEIPT - A quantity of SM or SNM in a shipment

received by a facility from another facility.

REFERENCE STANDARD -A material, device, or

instrument whose assigned value is traceable to a

national standard (i.e., primary standard) or nationally

accepted measurement system.

REMOVALS FROM INVENTORY - All measured

quantities of SM and SNM falling within the categories

of (1) shipments, (2)'measured discards released to the

environment, (3) measured discards transported offsite, and (4) measured discards stored on-site and

formally transferred in the accounting records to a

holding account via a DOE/NRC Form 741 transaction.

RESOLUTION OF AN INDICATOR - A definitive

determination (with auditable evidence) by the licensee

that an indicated possible theft or unauthorized

production of uranium has not occurred and is not

occurring.

RUNNING BOOK IN-PROCESS INVENTORY

(RBIPI) - The dynamic inventory of a process system

calculated by subtracting the cumulative measured

outputs from the process system (CO) from the

beginning inventory (BI) plus the cumulative measured

inputs to the process system (CI). Mathematically, this

can be expressed as:

RBIPI = BI + CI - CO

SHIPPER-RECEIVER DIFFERENCE (SRD) -The

difference between what a sending facility (i.e.,

shipper) claims was contained in a shipment (of SM or

SNM) and what the receiving facility claims was

received, where both shipper's and receiver's values are

based on measurement.

SOURCE MATERIAL (SM) - (1) Natural uranium

or thorium, or depleted uranium, or any combination

thereof, in any physical or chemical form, or (2) ores

that contain 0.05 wt % or more of (a) uranium, (b)

thorium, or (c) any combination thereof. Source

material does not include SNM.

SPECLAL NUCLEAR MATERIAL (SNM) - (1)

Plutonium, U-233, uranium enriched in U-235, and any

other material that the NRC, pursuant to the

provisions of Section 51 of the Atomic Encrgy Act of

1954 (as amended), determines to be SNM; or (2) any

material artificially enriched in any of the foregoing.

There are three levels of strategic significance applied

to SNM, depending on the type and quantity, defined

as follows:

NUREG/CR-5734 44
Glossary

SNM OF HIGH STRATEGIC SIGNIFICANCE -

Same as FORMULA QUANTITY (sec definition).

SNM OF MODERATE STRATEGIC SIGNIFICANCE - (1) Less than a formula quantity, but

more than 1,000 grams of U-235 contained in

HEU, or more than 500 grams of U-233 or

plutonium, or more than a combined quantity of

1,000 formula grams when formula grams are

computed by the following equation:

formula grams = (grams U-235 in HEU) +

2 (grams U-233 + grams Pu)

or (2) 10,000 grams or more of U-235 contained in

LEU enriched to 10.00 wt % or more, but less

than 20.00 wt %, U-235.

SNM OF LOW STRATEGIC SIGNIFICANCE -

(1) Less than an amount of SNM of moderate

strategic significance, but more than 15 grams of

(a) U-235 contained in HEU, (b) U-233,

(c) plutonium, or (d) any combination thereof;

(2) less than 10,000 grams but more than 1,000

grams of U-235 contained in LEU enriched to

10.00 wt % or more (but less than 20.00 wt o)

U-235; or (3) 10,000 grams or more of U-235

contained in LEU enriched above natural but less

than 10.00 wt % U-235.

STANDARD -See definitions for CERTIFIED

STANDARD, CHECK STANDARD, CONTROL

STANDARD, PRIMARY STANDARD, and

REFERENCE STANDARD.

STANDARD DEVIATION - The random error (at

the 67 perccnt confidence level) associated with a

single value of a data set, which in turn' is also a

measure (or indication) of the precision relating to a

set of measurements (or set of data) pertaining to the

same item or sample of material. Standard deviation

is calculated as follows:

std. dev. = l :i 

nwhere

n = number of measurements performed

;= the value obtaincd for the i th

measurement for i = 1, 2, 3 ....... n

x = the average value for all n measurements

STANDARD ERROR - The random error (at the 67

percent confidence level) associated with the average,

or mean, value of a data set derived from repetitive

determinations on the same item or sample.

Mathematically, standard error is the standard

deviation divided by the square root of the number of

individual measurements used to derive the mean

value.

STANDARD ERROR OF THE INVENTORY

DIFFERENCE (SEID) - (1) For licensees subject to

10 CFR 74.31 or 74.33, SEID is equal to the square

root of the sum of both measurement and nonmeasurement variances associated with the ID.

(2) For licensees subject to 10 CFR 74.59, SEID is

equal to the square root of only the measurement

variance associated with the ID.

STANDARD REFERENCE MATERIAL - A

material or substance that qualifies as a primary

standard and whose concentration with rcspect to a

nuclide or isotope, a chemical element, or chemical

compound is certified within a specified uncertainty.

SYSTEMATIC ERROR - A unidirectional error that

affects all members of a data set. The terms bias" and

"systematic error" are often interchanged. However,

any determined bias (i.e., a bias estimated from control

standard measurements) has an uncertainty value

associated with it. Thus, after correcting for any

estimated bias, the uncertainty of that bias can be

regarded as a systematic error. If an estimated bias is

not applied as a correction, the combination of the

bias plus its uncertainty should be regarded as the

systematic error.

TRACEABILITY - The ability to relate individual

measurement results to national standards (i.e.,

primary standards) or nationally accepted measurement

systems through an unbroken chain of comparisons.

UNAUTHORIZED PRODUCTION - (1) The misuse

of plant or equipment to deliberately produce uranium

at an enrichment level greater than permitted by

license, or (2) the production of a quantity of enriched

uranium grcater than reported to the NRC (e.g., by

undeclared feed or by unrecorded lowering of the tails

assay).

45 NUREG/CR-5734
NRC FORM 335 U.S. NUCLEAR REGULATORY COMMISSION . REPORT NUMBER

(2-89) (Assigned by NRC. Add Vol., Suspp., Rev..

NRCM 1102, end Addendum Numbers, if mny.)

3201,3202 BIBLIOGRAPHIC DATA SHEET

Mc instructions on the reverse) NUREG/CR-5734

2. TITLE AND SUBTITLE K/ITP-415

Recommendations to the NRC on Acceptable Standard Format and

Content for the Fundamental Nuclear Material Control (FNMC) 3. DATEREPORTPUBLISHED

Plan Required for Low-Enriched Uranium Enrichment Facilities MONTH YEAR

November 1991

4. FIN OR GRANT NUMBER

L1300

5. AUTHORIS) 6. TYPE OF REPORT

B.W. Moran, W.L. Belew, Oak Ridge K-25 Site Technical

G.A. Hammond, L.M. Brenner, 21st Century Industries, Inc. 7.PERIOD COVERED (inciusive ares)

8. PERFORMING ORGANIZATION -NAME AND ADDRESS li NRC.provide Division, Office or Region, U.S. Nuclear RegulatoryCommission andmailing address;iitcontractor, provide name and mailing addrss.)

Oak Ridge K-25 Site

Oak Ridge, TN 37831

Subcontractor: 21st Century Industries, Inc.

P. 0. Box 2636

Gaithersburg, MD 20886

9. SPONSORING ORGANIZATION - NAME AND ADDRESS Ill NRC. type "Same as aba ve"ii contractor, provide NRC Division. Ollice or Region, U.S. Nuclear Regulatory Commission.

9. SPONSO R ING ORGAN IZATION -NAME AND ADD RESS i NRC, tpe Soab ow-e;iftcontractor,provide NRCDOivision, Ofiikeor Region, US Nuciear Reguiatorv Commission,

and mailing address.)

Division of Safeguards and Transportation

Office of Nuclear Material Safety and Safeguards

U.S. Nuclear Regulatory Commission

Washinqton, DC 20555

10. SUPPLEMENTARY NOTES

11. ABSTRACT 200 words or less)

A new section, 10 CFR 74.33, has been added to the material control and accounting (MC&A)

requirements of 10 CFR Part 74. This new section pertains to U.S. Nuclear Regulatory Commission (NRC) -

licensed uranium enrichment facilities that are authorized to produce and to possess more than one effectivc

kilogram of special nuclear material (SNM) of low strategic significance.

The new section is patterned after 10 CFR 7431, which pertains to NRC licensees (other than

production or utilization facilities licensed pursuant to 10 CFR Part 50 and waste disposal facilities) that are

authorized to possess and use more than one effective kilogram of unencapsulated SNM of low strategic

significance. Because enrichment facilities have the potential capability of producing SNM of moderate

strategic significance, and also strategic SNM, certain performance objectives and MC&A system capabilities

are required in 10 CER 74.33 in addition to those contained in 10 CFR 74.31.

This document recommends to the NRC information that the licensee or applicant should provide

in the fundamental nuclear material control (FNMC) plan. This document also describes methods that should

be acceptable for compliance with the general performance objectives. While this document is intended to

cover various uranium enrichment technologies, the primary focus at this time is gas centrifuge and gaseous

diffusion.

12. KEY WORDS/DESCR!PTORS IList words or phrases that will assis researchers In locating the report. 13. AVAILABILITY STATEMENT

Enrichment Unlimited

Safeguards 14. SECURITY CLASSIFICATION

Source Material I This Page

Special Nuclear Material Unclassified

Material Control (Ths Repo)

Material Accountability Unclassified

Fundamental Nuclear.Material Control:- 15. NUMBER OF PAGES

Low-Enriched Uranium

16. PRICE

NRC FORM 335 12-891
THIS DOCUMENT WAS PRINTED USING RECYCLED PAPER
UNITED STATES

NUCLEAR REGULATORY COMMISSION

WASHINGTON, D.C. 20555

OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE, 300

PERMIT No. G-67

I