21J. Kang (ed.), Assessment of the Nuclear Programs of Iran and North Korea, DOI 10.1007/978-94-007-6019-6_2, © Springer Science+Business Media Dordrecht 2013

1 Introduction

This chapter contains a technical analysis of the 100 MWth LWR (in the event of its successful construction) and the Yongbyon uranium enrichment plant that constitute the DPRK’s main nuclear facilities. The analysis is primarily based on a November 12, 2010 meeting between Dr. Siegfried Hecker, the former director of Los Alamos National Laboratory, who is currently with Stanford University, USA, and North Korean of fi cials. During this meeting, North Korean Of fi cials disclosed the existence of an experimental light water reactor (LWR) program and uranium enrichment facility. The chapter also describes a veri fi cation methodology for the entire DPRK nuclear program, including sites, methods and overarching objectives.

2 The DPRK’s New Nuclear Facilities

2.1 100 MWth LWR

Table 1 summarizes the speci fi cations of the DPRK’s light water reactor (LWR) design according to information obtained by Dr. Siegfried Hecker from North Korean of fi cials. The most important characteristic of this reactor that is of interest to the international community is its power rating. The DPRK government informed Dr. Hecker that the LWR is designed to generate around 100 MW of thermal power (100 MWth). However, North Korea was reluctant to disclose its electric power

Verifying the DPRK Nuclear Program

Jin-Soo An

J.-S. An (*) Nonproliferation Research Division, Korea Institute of Nuclear Nonproliferation and Control (KINAC) , 573 Expo-ro , Yuseong-gu, Daejeon 305-348 , Republic of Korea e-mail: jsan@kinac.re.kr

22 J.-S. An

generation capacity and instead said that thermal ef fi ciency (the transformational ef fi ciency from heat power to electric power) was approximately 30%. Accordingly, Dr. Hecker estimates the LWR’s electric power at around 25–30 MWe (Hecker 2010 ) .

According to Dr. Hecker, DPRK of fi cials declared that they had independently fabricated reactor-related parts, including the reactor vessel, pumps and LWR fuel, and that the DPRK possesses suf fi cient uranium ore reserves to fuel the reactor. They also said that research into the manufacture of uranium-dioxide (UO

2 )-type

fuel was currently in progress and that North Korea would soon initiate domestic UO

2 manufacture without external support. In addition, DPRK of fi cials reported

that they had not decided upon whether to use zircaloy or stainless steel for the clad-ding. Other details, such as operating pressure and temperature, coolant fl ow rate, as well as information about the moderator and burn-up rate were not veri fi ed.

The primary system of the LWR, such as the reactor vessel, should be capable of enduring high temperature and pressure. Therefore, LWR fabrication necessarily requires high levels of technology and substantial experience. However, some of these challenges can be mitigated by decreasing the target heat ef fi ciency of the power plant because that would diminish the heat and pressure burden on the primary system.

North Korean of fi cials were especially reluctant to disclose speci fi c electric power generation capabilities to Dr. Hecker. This could be due to equipment perfor-mance defects, construction problems or a general reluctance to admit shortcomings in their LWR fabrication program.

2.2 Uranium Enrichment Facility

According to what North Korean of fi cials told Dr. Hecker on November 12, 2010, the uranium enrichment facility had been built in April 2009 and begun operation in early November 2010, several days prior to Dr. Hecker’s visit to North Korea. Dr. Hecker reported that he saw panels and LED displays within the facility’s control

Table 1 Yongbyon 100 MWth LWR: known speci fi cations

Thermal power 100 MW th

Heat ef fi ciency ~30% Estimated by DPRK scientist Electric power 25–30 MW

e Estimated by Hecker

Fuel type UO 2 Cladding material not fi xed

as of December 2010. Fuel enrichment Average 3.5% (2.2–4%) Fuel 1 core Quantity

(U base) 4,000 kg

Pressure vessel High-strength steel Possibly with a stainless steel liner

Containment vessel ~ D: 22 m, H: 40 m, Thick : 0.9 m

Reinforced concrete

23Verifying the DPRK Nuclear Program

room listing operating parameters. Hecker also reported that the facility had fi ve large panels toward the rear that had numerous LED displays with similar opera-tional information.

North Korea argues that this enrichment facility is intended to supply fuel (3.5% low enriched uranium) to their experimental LWR, which is currently under construction. The points below summarize characteristics of the enrichment facility that are either known or estimable:

Location: Yongbyon Nuclear Fuel Fabrication Plant (re-modeled U-metal manu-• facturing facility, 39.7701 N, 125.7493 E) Chronology:•

Commencement of Construction: April 2009 – Commencement of Operation: Early November 2010 –

Building Size: 120 m × 18 m (two story building) • Capacity: 8,000 kg-SWU/year (per North Korean announcement) • Number of Centrifuges/Cascades/Zone: 2,000/6/2 • Centrifuge Speci fi cations:•

Type: P-2 – 1 (G-2) Outside Diameter: about 20 cm (8 in.) – Height: About 1.8 m (6 ft) – Enrichment Capacity: About 4 kg-SWU/year – Rotor: Iron alloy (Possibly maraging steel) – Case: Aluminum (Probably?) –

Enrichment Level of Product/Tail: Average 3.5%/0.27% • Enriched Uranium Production Capacity (estimated value)•

LEU (3.5%): about 1,800 kg/year – HEU (90%): about 40 kg/year –

Based on disclosed information regarding the Yongbyon enrichment facility, it is possible to deduce the following with regard to the DPRK’s uranium enrichment program:

Since North Korea was able to build centrifuges on the above-mentioned scale • within the relatively short period of one and half years, there could be separate enrichment facilities in another location. Also, the North could build additional clandestine enrichment facilities in the future. Although North Korea reported that it operates all 2,000 centrifuges in the enrich-• ment facility, based on other cases (such as Iran), it is probable that the DPRK will experience dif fi culties in operating centrifuges on this scale.

1 Dr. Hecker reported that North Korea were “most likely” to be “P-2 centrifuges (which were based on the German G-2, that was developed by the Germans as part of the URENCO consor-tium), which typically have high-strength maraging steel rotors that can by spun much faster than the aluminum rotors, thereby increasing the throughput.”

24 J.-S. An

Even though North Korea argues that this facility is intended for the production • of low enriched uranium, the facility could easily be diverted to produce HEU for nuclear weapons. If diverted, the facility could produce around 40 kg of HEU per year, from which one or two HEU bombs could be manufactured. In the context of negotiations over denuclearization, verifying DPRK compli-• ance with any eventual agreement will be dif fi cult. North Korea is not eager to abandon its uranium enrichment program and continues to justify its ongoing nuclear program under the guise of the peaceful pursuit of nuclear power.

3 Veri fi cation

The purpose of veri fi cation is to verify a nation’s reported nuclear-related activities and con fi rm non-existence of un-declared activities.

3.1 Programs and Items to Verify

Issues related to DPRK nuclear veri fi cation can be broadly grouped into (a) the plu-tonium production program, (b) the uranium enrichment program, and (c) the nuclear weapons production program. The complete veri fi cation of North Korea’s nuclear weapons development program, based on Fig. 1 , requires the veri fi cation of:

the history and current status of all nuclear materials that North Korea has • produced, stored or used the history of development of nuclear weapons and their current status • the history and current status of facilities and equipment used for nuclear weapons • development the facilities that manufacture equipment that is used for nuclear weapon • development the current status of human power, especially scientists and engineers, involved • in nuclear weapon related activities

3.2 Major Veri fi cation Methods

In order to verify DPRK compliance, it is necessary to inspect documents, conduct extensive interviews with people involved in the associated programs, and perform nuclear material measurement and sampling.

Document inspection: Match reported data with actual operational records, • verify design information, compare the information in documents with measure-ments on existing nuclear materials and the measurement management record. Record and interview: Photograph and interview key personnel in order to verify • facility scale, instruments, and organizational manpower.

25Verifying the DPRK Nuclear Program

Nuclear material veri fi cation (measurement and sampling): Measure existing • nuclear materials or analyze samples using Non-Destructive Assay or Destructive Assay techniques. 2

3.3 Major Veri fi cation Items by Subject

3.3.1 Plutonium Program-Related Items

Grouped by Facility

Facility and materials

Grouping Items Veri fi cation items

1. Fuel cycle-related facility Uranium Mine Scale, ore quality, operational history Re fi nery Plant Capacity, operational history Conversion Plant Capacity, process, operational history Metalizing Plant Capacity, process, operational history

(continued)

2 Non-Destructive Assay (radiation measurement): A technique that verifies nuclear material’s provenance, quantity and enrichment level by analyzing emitted radiation from the nuclear mate-rial without inducing any physical transformation of the nuclear material.

Fig. 1 DPRK nuclear material fl ow diagram (KINAC (Korea Institute of Nuclear Nonproliferation and Control) Technical Report KINAC/TR-008/2011, p. 47)

26 J.-S. An

– Destructive Assay (chemical analysis): A technique that verifies a nuclear material’s quantity or isotope ratio by sampling a portion of the nuclear material itself or by using an environmental sample from the vicinity of the facility and measuring chemical properties.

– Other techniques: Measure the physical properties of tested sample (weight, thickness of the container, density, etc.)

Facility and materials

Grouping Items Veri fi cation items

2. Nuclear materials Natural Uranium Stock, chemical form, history Plutonium Stock, isotope composition/ratio,

chemical form, history Fuel (New Fuel) Stock, history

3. Reactor 5 MWe GMR Operational history (including thermal power), Spent fuel history

50 MWe GMR Present state 200 MWe GMR Present state IRT-2000 Operational history, spent fuel history,

nuclear material irradiation history Critical Device Operational history and present state

4. Spent fuel 5 MWe Spent Fuel Quantity produced, burn-up, present state, quantity reprocessed

IRT-2000 Spent Fuel Quantity, burn-up, present state 5. Reprocessing plant Radio-chemical

Experimental Laboratory

Capacity, operational history, quantity of recovered Pu

HLW a Storage Facility HLW quantity and composition MLW b Storage Facility MLW quantity and composition

6. Research facility Yongbyon Nuclear Research Center

Scale of facility, substance of study

Universities ” Other Nuclear Research

Laboratories ”

7. Materials and instrument manufacturing facility

Reactor Instruments Scale, instrument production quantity and quality

Uranium Production Related Materials and Instruments

”

Reprocessing-Related Materials and Instruments

”

Import Materials and Instruments

Verify quantity imported, used, and stocked

8. Workers Human Power and Organization

Past and present state veri fi cation

Interview Activity veri fi cation

(continued)

a High level radioactive waste b Medium level radioactive waste

27Verifying the DPRK Nuclear Program

Materials to Verify

Material Use Remarks

1 Uranium ore Uranium production Mine scale, ore quantity and quality, gangue quantity

2 Yellow cake Uranium production TBP, HNO 3 , H

2 SO

4 , etc.

3 UF 4 Uranium metalizing

or F 6 production

HF, F 2 , CaF

2 , H

2 SO

4 , etc.

4 UF 6 Enrichment ”

5 Uranium metal Fuel production Electric furnace, Ca and/or Mg metal powder 6 Fuel rod Reactor operation Fuel fabrication facility, cladding materials 7 Spent fuel Pu production Reprocessing plant, TBP, HNO

3 , H

2 SO

4 ,

NaOH, etc. 8 Plutonium Weapons manufacture HF, F

2 , CaF

2 , H

2 SO

4 , H

2 C

2 O

4 , Ca and/or Mg

metal powder, I 2 , etc.

Veri fi cation of Plutonium Production

The veri fi cation of DPRK’s plutonium program will require historical and current data on all related activity of the DPRK. However, the plutonium production reactor in North Korea, the 5 MWe graphite reactors, are unique because plutonium outturn would be veri fi ed using the GRIM (Graphite Isotope Radio Method). It is estimated that this technique will allow for a fairly accurate con fi rmation of plutonium produc-tion; estimates suggest an error range of 1–10% (Gesh 2004 ) or even below 3% (Reid et al. 1999 ) . But this would require utmost cooperation on the part of the DPRK.

3.4 Uranium Enrichment Program-Related Items

First, an agreement on speci fi c veri fi cation methods and steps for the dismantlement of North Korea’s uranium enrichment program should be prepared through negotiations such as the Six Party talks. The most important issues requiring agreement regard sam-pling the North’s declared uranium enrichment related facilities and broad environ-mental sampling in order to detect undeclared uranium enrichment related facilities.

In addition, it would be desirable to negotiate full access (including “snap inspec-tions”) to other suspicious facilities as mandated by the IAEA Additional Protocol. Access should include even those facilities where military or commercial con fi dentiality is claimed provided the IAEA presents adequate justi fi cation for requesting access. For this to occur, the DPRK must agree to the IAEA Additional Protocol or submit to similarly invasive inspections.

Another veri fi cation issue is the history of North Korea’s uranium enrichment program. This entails the veri fi cation of: (a) External support to North Korea’s uranium enrichment program development (e.g. Pakistani support from the late 1990s to the early 2000s), (b) North Korean support to 3rd party countries’ uranium enrichment efforts (e.g. UF

6 export to Libya in the early 2000s), and (c) North Korea’s independent

28 J.-S. An

3 North Korea insists that it developed all uranium enrichment programs with its own indigenous technology and resources.

uranium enrichment program. 3 With these measures, undeclared uranium enrichment activities as well as cases of nonproliferation regime violations could be detected.

In advance of any veri fi cation regime, an agreement on target facilities and the scope of the DPRK uranium enrichment program must be agreed upon through some negotiation format (such as the Six Party Talks) and North Korea should accordingly carry out the agreed-upon nuclear declaration.

3.4.1 Veri fi cation Target Facilities

No. Category Activity or name Veri fi cation item Method

1 Mine/re fi ning Uranium production

Same as Pu veri fi cation program

2 Conversion UF 6 production Site location, capacity,

material balance (U, F

2 , etc.)

Document inspection (design information, log book, etc.), worker interview, inspection, measurement,

3 Enrichment Yongbyon Enrichment Plant

Capacity, plant design, centrifuge quantity and spec. material balance (HEU/LEU/DU) organization and manpower

Unknown enrichment plants

Site location, capacity, centrifuge quantity and spec. material balance (HEU/LEU/DU) organization and manpower

NDA and sampling

4 Research Enrichment research and development

Site location, facility scale and capacity, research substance, research history, organization and manpower

5 Nuclear-related equipment and materials production and/or imports

Local production

Produce, use, stock

Imports Imports, use, stock

(continued)

29Verifying the DPRK Nuclear Program

No. Category Activity or name Veri fi cation item Method

6 Enrichment equipment production (centrifuge, magnetic bearing, etc.)

Equipment production

Site location, facility scale and capacity, research substance, production history, import and export history of equipment and materials, organization and manpower

3.4.2 Materials to Verify

No. Material Use Remarks

1 Uranium ore Uranium production Mine scale, ore quantity and quality, gangue quantity

2 Yellow cake Uranium production TBP, HNO 3 , H

2 SO

4 , etc.

3 UF 4 UF

6 production HF, F

2 , CaF

2 , H

2 SO

4 , etc.

4 UF 6 Uranium enrichment F

2 , etc.

5 Centrifuge components and materials

Centrifuge production High strength materials (aluminum alloy, maraging steel, carbon fi ber, etc.) and high ferromagnetic body, etc.

6 HEU metal Weapons manufacturing Ca, CaF 2 , Mg, MgF

2 , etc.

3.5 Nuclear Weapons Program-Related Items

3.5.1 Veri fi cation Target Facilities

Classi fi cation

Veri fi cation items Category Detail category

1. Weapons/wapons-grade Nuclear weapons Quantity, speci fi c character Nuclear material Plutonium Quantity, speci fi c character

HEU Quantity, enrichment, speci fi c character

Related facilities Weapons manufacturing Scale, speci fi c character Weapons storage Scale, con fi guration, location

2. Weapons study Weapons research Scale, substance of study High explosives tests Scale, location, experimental history,

test instrument, method, etc.

(continued)

30 J.-S. An

3.5.2 Nuclear Weapons-Related Instruments and Devices

Instrument/device Use Related material and facility

1 Implosion device Nuclear material compression

Weapons manufacturing facility, high explosive testing fi eld

2 Neutron generation device

Neutron supply for fi ssion

Alpha emitter (Po-210, Ac-227, etc.) beryllium, tritium, particle acceleration electrode tube

3 SAFF system a Weapons management for safety and control

Weapons manufacturing facility

a Sa fi ng, arming, fusing, fi ring system

3.5.3 Nuclear Weapons-Related Material

Material Use Related material and facility

1 Pu Weapons manufacture Reprocessing plant 2 HEU Weapons manufacture Enrichment plant 3 Po-210 Firing device manufacture Bismuth, IRT-2000 4 H-3 Neutron generation device

manufacture, boosting Li-6, IRT-2000

5 Li-6 Boosting H-3 production Li enrichment plant 6 Beryllium Re fl ector Weapons manufacturing

facility 7 High density materials Tamper 8 High explosives Firing device manufacture

3.5.4 Nuclear Testing Ground Veri fi cation

North Korea has performed two nuclear tests at a nuclear testing facility in Poongye-ri, Kilchu-gun, Hamgyongbuk-do. Veri fi cation of the test site is also required. Veri fi cation items are as follows:

Location: locations of tunnel entrances, zero rooms, various aids • Types and number of facilities • Type of Detonator • Nuclear material: Type and quantity of nuclear materials used in tests • Explosive power: Hypothetical explosive power versus actual explosive power • (verify whether boreholes were drilled in order to sample after nuclear test; verify measurement result) Type, performance, and quantity of nuclear test observation-related equipment • Type, performance, and quantity of nuclear testing ground facilities and maintenance-• related equipment

31Verifying the DPRK Nuclear Program

Type, performance, and quantity of other nuclear test-related equipmentType, • performance, and quantity of other nuclear test-related equipment Others:•

Nuclear test data – Existence of critical, subcritical experimental facilities – Evidence of thermonuclear testing –

4 Conclusion

This chapter has provided an overview of what is known about the North Korean experimental light water reactor and uranium enrichment facility. Based on what was disclosed by North Korean of fi cials to Dr. Siegfried Hecker during a November 12, 2010 meeting, it appears that the light water reactor that North Korea is con-structing is designed to generate 100 MW of thermal power and its core will contain about 4,000 kg of low-enriched uranium (LEU). The uranium centrifuge program is estimated to have 2,000 centrifuges with a total capacity of 8,000 kg-SWU/year. This can produce about 1,800 kg/year of LEU (3.5%) or about 40 kg/year of HEU (90%).

The central goal of veri fi cation in the DPRK case is to determine the exact quantities of weapons grade material (Pu, HEU) produced and used by the DPRK. This will involve understanding in great detail the histories of and what have been produced by the uranium enrichment program, the plutonium production program, and the nuclear weaponization program. Under ideal circumstances and with an extensive effort, this goal should be partially achievable. With active DPRK cooperation, the quantity of Pu can be con fi rmed almost exactly with a margin of error of a few percent by GRIM (Graphite Isotope Radio Method). However, no technical method currently exists for accurately determining the quantity of HEU produced. Additionally, HEU veri fi cation will become more dif fi cult as time passes. However, some useful information may be available through interviews of personnel involved in these programs and the examination of historical documents.

Appendices

Appendix A

Table 2 provides estimates of the minimum temperatures and pressures required for operation, based on operational data from existing 1,000 MWe-class PWRs (assum-ing a 1,000 MWe LWR’s heat power is 2,815 MWth, reactor temperature is 323°C

32 J.-S. An

Tabl

e 2

Tem

pera

ture

s an

d eq

uilib

rium

ste

am p

ress

ures

for

Pri

mar

y Sy

stem

by

heat

ef fi

cien

cy le

vels

Rea

ctor

ope

ratio

n co

nditi

on

Rea

ctor

des

ign

base

s (o

pera

tion

tem

p. +

27)

Tem

p. (

°C)

Equ

ilibr

ium

st

eam

pre

ssur

e (k

gf/c

m 2 )

Rat

io (

stea

m p

ress

ure)

/(1

,000

MW

e LW

R

stea

m p

ress

ure)

Te

mp.

(°C

)

Equ

ilibr

ium

st

eam

pre

ssur

e (k

gf/c

m 2 )

Rat

io (

stea

m p

ress

ure)

/(1

,000

MW

e LW

R s

team

pr

essu

re)

1,00

0 M

We

LWR

(3

5.5%

) 32

3.0

119.

7 1

350

168.

5 1

Hea

t ef fi

cien

cy 3

0%

254.

0 43

.3

0.36

28

1 66

.3

0.39

H

eat e

f fi ci

ency

25%

20

3.8

17.1

0.

143

230.

8 28

.9

0.17

H

eat e

f fi ci

ency

20%

16

2.4

6.7

0.06

18

9.4

12.6

0.

075

a Bas

ed o

n th

e as

sum

ptio

n th

at a

1,0

00 M

We

LWR

’s h

eat p

ower

is 2

,815

MW

th, r

eact

or te

mpe

ratu

re is

323

°C, a

nd c

onde

nser

tem

pera

ture

is 5

0°C

b B

ased

on

the

abov

e co

nditi

ons,

we

assu

me

that

act

ual h

eat e

f fi ci

enci

es in

all

case

s ar

e 77

.5%

of

idea

l ef fi

cien

cies

33Verifying the DPRK Nuclear Program

and condenser temperature is 50°C 4 ). However, without the detailed operational parameters of North Korea’s reactor, these estimates are necessarily approximate. Therefore this approximation demonstrates the hypothetical temperature and pres-sure burden exerted on the LWR’s main elements based on differing heat ef fi ciency levels.

As shown in the table above, for example, by decreasing heat ef fi ciency from 35.5 to 25%, the temperature required for operation of the LWR’s Primary System drops by 119 and pressure drops to 1/6 level of the previous level. This indicates that it is possible to manufacture a reactor vessel and other related instruments utilizing a lower level of technology by sacri fi cing heat ef fi ciency.

4 To smooth calculations, in calculating reactor efficiency, we assume that heat efficiencies in all cases were 77.5% of the ideal heat engine’s heat efficiencies.

[Reference] Table 2 Calculations (Fig. 2 )

Fig. 2 A schematic of PWR Nuclear Steam Supply System (This fi gure modi fi ed from http://en.wikipedia.org/wiki/File:PressurizedWaterReactor.gif )

(continued)

34 J.-S. An

5 This is a hypothetical temperature. 6 In the absence of actual temperature information we substituted an arbitrary temperature. If temperature changes, heat efficiency would change, but the system and overall trends would not change significantly.

The 1,000 MWe class LWR’s heat power is approximately 2,815 MWth, so its heat ef fi ciency is approximately 35.5%. In a normal operational state, this reactor’s temperature is approximately 323°C 5 (with an equilibrium steam pressure of 119.7 kgf/cm 2 ). Assuming the Secondary System condenser’s temperature is 50°C, 6 the theoretical heat ef fi ciency is as follows, based on the second law of thermodynamics: Given following equation, a 1,000 MWe reactor’s maximum theoretical heat ef fi ciency is 45.8%.

Here, theoretical heat ef fi ciency = (T 1 − T

2 )/T

1

T 1 = high temperature of engine (absolute temperature)

T 2 = lower temperature of engine (condensate temperature in steam turbine)

With a theoretical heat ef fi ciency of 45.8% and an actual heat ef fi ciency of approximately 35.5% (due to heat losses and mechanical problems), the esti-mated ratio between theoretical and actual heat ef fi ciency is about 77.5%. Therefore, based on this measure, actual ef fi ciency should be 77.5% of the theoretical ef fi ciency. This parameter would require a reactor core tempera-ture (x) (under a case of 25% heat ef fi ciency) of 203.8°C, which is 119°C lower than 323°C. The equilibrium steam pressure of 203.8° is 17.12 kgf/cm 2 , which is much lower than 119.7 kgf/cm 2 . (Approximately 14% of equilibrium steam pressure for 323°C).

Moreover, for safety reasons, reactor vessels are designed to endure up to 350°C (equilibrium steam pressure of 168.5 kgf/cm 2 , which is 27°C higher than the operational temperature. Under a case of 25% heat ef fi ciency, again due to safety considerations, an equilibrium steam pressure of 230.8, which is 27°C higher than 203.8°C (operational temperature), is merely 28.9 kgf/cm 2 , which is 17% of 350.

Although North Korea is currently unable to build a 1,000 MWe class LWR, it might be able to build a small-sized experimental LWR with lowered heat ef fi ciency. Successfully operating a LWR could provide the DPRK with justi fi cation for continued uranium enrichment. Moreover, in the context of negotiations over denuclearization, the DPRK could use the LWR facility as a bargaining chip or seek to extract compensation in exchange for its abandonment.

[Reference] Table 2 Calculations (Fig. 2)—(continued)

Appendix B

Veri fi cation Instruments (Based on IAEA Inspection Instruments)

(1)

Ver

i fi ca

tion

Mea

sure

men

ts a

t Nat

ural

and

Low

Enr

iche

d U

rani

um C

onve

rsio

n an

d Fa

bric

atio

n Pl

ants

(IA

EA

, IA

EA

Saf

egua

rds

Man

ual

SMC

5 (2

003)

, p. 1

3)

Mat

eria

l C

ateg

ory

Mai

n st

ratu

m

Mat

eria

l typ

e co

mpo

nent

s D

efec

t ty

pe

Def

ect d

escr

iptio

n M

easu

rem

ents

req

uire

d A

pplic

able

m

etho

d R

ecom

men

ded

inst

rum

ents

In-d

irec

t-us

e Fr

esh

fuel

(as

sem

blie

s bu

ndle

s, r

ods)

(F

F, F

R)

DU

, NU

, LE

U

Gro

ss

Rep

lace

d by

dum

my,

or

mis

sing

Id

enti fi

catio

n, r

adia

tion

()

U r

adia

tion

(LE

U)

A (

1), H

M

MC

N, M

MC

C,

MM

CG

, HM

-5

LE

U

Part

ial

Low

er U

-235

C

onte

nt

U a

nd U

-235

Con

tent

F

UN

CL

+ H

M-5

(2),

FR

SC,

MM

CN

+ H

M-5

(2)

D

U, N

U, L

EU

B

ias

(4)

U c

onte

nt b

ias

U a

nd U

-235

con

tent

B

+ D

(3

) FR

SC

Sint

ered

pel

lets

(PL

),

gree

n pe

llets

, po

wde

r (P

D),

sc

rap

(SC

)

DU

, NU

, LE

U

Gro

ss

No

uran

ium

U

rad

iatio

n H

M

MC

N, M

MC

C,

MM

CG

, HM

-5 (

4)

Part

ial

Part

of

uran

ium

m

issi

ng

U a

nd U

-235

con

tent

B

+ F

E

BA

L +

MM

CN

LE

U

Bia

s U

con

tent

bia

s U

and

U-2

35 c

onte

nt

B +

D

EB

AL

+ D

A

UF 6 c

ylin

der

(VF)

(5)

L

EU

G

ross

N

o ur

aniu

m

Ura

nium

pre

senc

e H

A

cous

tic +

MM

CN

or

MM

CG

(6)

Pa

rtia

l L

ower

U-2

35

cont

ent

U a

nd U

-235

con

tent

B

+ F

L

CB

S +

MM

CG

+ U

LTG

, L

CB

S +

MM

CN

B

ias

U c

onte

nt b

ias

U a

nd U

-235

con

tent

B

+ D

L

CB

S +

DA

N

U

Gro

ss

No

uran

ium

U

rani

um p

rese

nce

H

Aco

ustic

+ M

MC

N o

r M

MC

G (

6)

Part

ial

Part

of

uran

ium

m

issi

ng

U c

onte

nt

B +

H (

7)

LC

BS

+ M

MC

N o

r M

MC

G

(con

tinue

d)

Mat

eria

l C

ateg

ory

Mai

n st

ratu

m

Mat

eria

l typ

e co

mpo

nent

s D

efec

t ty

pe

Def

ect d

escr

iptio

n M

easu

rem

ents

req

uire

d A

pplic

able

m

etho

d R

ecom

men

ded

inst

rum

ents

DU

G

ross

N

o ur

aniu

m

Ura

nium

pre

senc

e H

A

cous

tic +

MM

CN

or

MM

CG

(6)

W

aste

D

U, N

U, L

EU

G

ross

N

o ur

aniu

m

Rad

iatio

n (D

N)

U

radi

atio

n (L

EU

) H

M

MC

N, M

MC

C,

MM

CG

, HM

-5

Not

es:

(1)

Whe

re a

pplic

able

. (2

) H

M-5

use

d fo

r ac

tive

leng

th m

easu

rem

ent.

(3)

Pelle

t sam

plin

g at

rod

load

ing

stat

ion

(+E

BA

L).

A r

od s

cann

er m

ay b

e us

ed in

stea

d if

the

nucl

ear

mat

eria

l con

tent

in th

e ro

ds is

det

erm

ined

with

RSD

< 0

.06:

in

this

cas

e w

eigh

ing

is n

ot r

equi

red.

(4

) H

M-5

not

to b

e us

ed w

ith n

este

d (g

ross

+ p

artia

l + b

ias

defe

cts)

sam

plin

g pl

ans.

(5

) Fo

r U

F6 th

e op

erat

or’s

dec

lara

tion

of u

rani

um c

once

ntra

tion

is a

ccep

ted

if it

doe

s no

t dif

fer

by m

ore

than

0.0

03 f

rom

the

stoi

chio

met

ric

valu

e (0

.676

).

(6)

For

veri

fyin

g he

els

in U

F 6 cyl

inde

rs, w

eigh

ing

and

radi

atio

n m

easu

rem

ents

can

be

used

. (7

) E

nric

hmen

t mea

sure

men

ts f

or n

atur

al U

F 6 are

not

req

uire

d fo

r pa

rtia

l def

ects

.

(con

tinue

d)

(2)

Ver

i fi ca

tion

Mea

sure

men

ts a

t Enr

ichm

ent P

lant

s (I

AE

A 2

003a

)

Mat

eria

l cat

egor

y M

ain

stra

tum

M

ater

ial t

ype

com

pone

nts

Def

ect t

ype

Def

ect d

escr

iptio

n M

easu

rem

ents

re

quir

ed

App

licab

le

met

hod

Rec

omm

ende

d in

stru

men

ts

in-d

irec

t- U

SE

UF 6 C

ylin

der

(UF)

(1)

L

EU

G

ross

N

o ur

aniu

m

Ura

nium

pre

senc

e H

A

cous

tic +

MM

CN

or

MM

CG

(2)

Pa

rtia

l L

ower

U-2

35

cont

ent

U a

nd U

-235

co

nten

t B

+ F

L

CB

S +

MM

CG

+ U

LTG

, L

CB

S +

MM

CN

B

ias

U c

onte

nt b

ias

U a

nd U

-235

co

nten

t B

+ D

L

CB

S +

DA

NU

G

ross

N

o ur

aniu

m

Ura

nium

pre

senc

e H

A

cous

tic +

MM

CN

or

MM

CG

(2)

Pa

rtia

l Pa

rt o

f ur

aniu

m

mis

sing

U

and

U-2

35

cont

ent

B +

H

LC

BS

+ M

MC

G +

ULT

G,

LC

BS

+ M

MC

N o

r M

MC

G

Bia

s (3

) U

con

tent

bia

s U

and

U-2

35

cont

ent

B +

D

LC

BS

+ D

A

DU

G

ross

N

o ur

aniu

m

Ura

nium

pre

senc

e H

A

cous

tic +

MM

CN

or

MM

CG

(2)

Pa

rtia

l Pa

rt o

f ur

aniu

m

mis

sing

U

con

tent

B

+ H

L

CB

S +

MM

CG

+ U

LTG

, L

CB

S +

MM

CN

or

MM

CG

B

ias

U c

onte

nt b

ias

U a

nd U

-235

co

nten

t B

+ D

L

CB

S +

DA

(con

tinue

d)

Mat

eria

l cat

egor

y M

ain

stra

tum

M

ater

ial t

ype

com

pone

nts

Def

ect t

ype

Def

ect d

escr

iptio

n M

easu

rem

ents

re

quir

ed

App

licab

le

met

hod

Rec

omm

ende

d in

stru

men

ts

LE

U/H

EU

U

-235

enr

ichm

ent

20%

A

bsen

ce o

f H

EU

H

, D

CH

EM

, CE

MO

, DA

LE

U/N

U/D

U

PAR

TIA

L

Part

of

uran

ium

m

issi

ng

U c

onte

nt

F PN

UH

Was

te

LE

U/N

U/D

U

Gro

ss

No

uran

ium

U

rani

um p

rese

nce

H

MM

CN

, MM

CC

, MM

CG

, H

M-5

Not

es:

(1)

The

ope

rato

r’s

decl

arat

ion

of u

rani

um c

once

ntra

tion

is a

ccep

ted

if it

doe

s no

t dif

fer

by m

ore

than

0.0

03 f

rom

the

stoi

chio

met

ric

valu

e (0

.676

).

(2)

For

veri

fyin

g he

els

in U

F 6 cyl

inde

rs, w

eigh

ing

and

radi

atio

n m

easu

rem

ents

are

req

uire

d.

(3)

App

licab

le to

fee

d cy

linde

rs w

here

fee

d m

ay b

e ot

her

than

nat

ural

ura

nium

acc

ordi

ng to

Des

ign

Info

rmat

ion.

(con

tinue

d)

(3)

Ver

i fi ca

tion

Mea

sure

men

ts a

t Gra

phite

Mod

erat

e R

eact

or (

IAE

A 2

003b

)

Mat

eria

l cat

egor

y M

ain

stra

tum

M

ater

ial t

ype

com

pone

nts

Def

ect t

ype

Def

ect d

escr

iptio

n M

easu

rem

ents

re

quir

ed

App

licab

le

met

hods

R

ecom

men

ded

inst

rum

ents

Uni

rrad

iate

d di

rect

ed u

se

Fres

h fu

el a

ssem

bles

, el

emen

ts (

FM),

ro

ds, p

ins,

pla

tes

(FR

), c

oupo

ns

(CP)

Pu H

EU

G

ross

R

epla

cem

ent w

ith

LE

U, o

r m

issi

ng

Pu r

adia

tion/

U

radi

atio

n H

M

MC

N, N

MC

G, M

MC

C

Part

ial

Rod

, pin

, pla

te,

coup

on

repl

acem

ents

U/U

-235

con

tent

, Pu

con

tent

F

UN

CL

+ M

H-5

for

HE

U

AW

CC

, PN

CL

+ H

RG

S fo

r M

OX

, H

LN

C +

HR

GS

Bul

k M

ater

ial (

SM)

Pu H

EU

G

ross

N

o U

/Pu

U r

adia

tion

H

MM

CN

, MM

CG

, MM

CC

Pu

rad

iatio

n Pa

rtia

l Pa

rt o

f U

Pu

mis

sing

U

/U-2

35 c

onte

nt/

Pu c

onte

nt

B +

F

EB

AL

+ M

MC

N +

ULT

G,

EB

AL

+ M

MC

G +

HLT

G

(HE

U)

HL

NC

+ H

RG

S(M

OX

) B

ias

U/P

u co

nten

t bia

s U

/U-2

35 c

onte

nt/

Pu c

onte

nt

B +

D

EB

AL

+ D

A

Irra

diat

ed

dire

cted

use

Sp

ent f

uel a

ssem

bles

, el

emen

t (SF

) sp

ent f

uel r

ods,

pi

ns, p

late

s (S

R)

PU, H

EU

DN

LE

U

Gro

ss

Rep

lace

d by

du

mm

y, o

r m

issi

ng

Rad

iatio

n H

IC

VD

, MM

CN

, SFA

T,

CPM

U, H

SGM

Irra

diat

ed b

ulk

mat

eria

l (IM

) PU

, HE

U, D

NL

EU

G

ross

N

o U

, or

Pu

Rad

iatio

n H

C

PMU

, HSG

M, M

MC

G,

MM

CN

, MM

CC

In

dire

ct u

se

Fres

h fu

el a

ssem

bles

, el

emen

ts (

FE),

fr

esh

fuel

rod

s,

pins

, pla

tes

(FR

),

Cou

pons

(C

P)

DN

LE

U

Gro

ss

Rep

lace

d by

du

mm

y, o

r m

issi

ng

Rad

iatio

n H

M

H-5

, MM

CN

, MM

CG

, M

MC

C

Bul

k m

ater

ial (

SM,

WA

, SC

) D

NL

EU

G

ross

N

o U

U

rad

iatio

n H

H

M-4

, MM

CN

, MM

CC

Pa

rtia

l Pa

rt o

f U

mis

sing

U

/U-2

35

radi

atio

n B

+ F

E

BA

L +

MM

CN

, E

BA

L +

MM

CG

+ U

LTG

L

EU

B

ias

U c

onte

nt b

ias

U/U

-235

con

tent

B

+ D

E

BA

L +

DA

(4)

Ver

i fi ca

tion

Mea

sure

men

ts a

t Rep

roce

ssin

g Pl

ants

(IA

EA

200

3c )

Mat

eria

l cat

egor

y M

ain

stra

tum

M

ater

ial t

ype

com

pone

nts

Def

ect t

ype

Def

ect d

escr

iptio

n M

easu

rem

ents

re

quir

ed

App

licab

le

met

hods

R

ecom

men

ded

inst

rum

ents

Uni

rrad

iate

d di

rect

ed u

se

Pu n

itrat

e so

lutio

n (S

O)

Pu

Gro

ss/p

artia

l/bia

s N

o Pu

, Par

t of

Pu

mis

sing

, Pu

cont

ent b

ias

Pu C

onte

nt

(B o

r C

) +

(D

or

E)

EB

AL

or

ELT

M +

DA

or

KE

DG

PuO

2 pow

der

(PD

) Pu

G

ross

N

o Pu

Pu

rad

iatio

n H

H

LN

C, M

MC

G, M

MC

N,

MM

CC

Pa

rtia

l Pa

rt o

f Pu

mis

sing

Pu

con

tent

F

B +

F

HL

NC

+ H

RG

S E

BA

L +

INV

S +

HR

GS

Bia

s Pu

con

tent

bia

s Pu

con

tent

B

+ D

E

BA

L +

DA

D

isso

lver

sol

utio

n (D

S)

Pu

Gro

ss/p

artia

l/bia

s N

o Pu

, Par

t of

Pu

mis

sing

, Pu

cont

ent b

ias

Pu c

onte

nt

C +

D o

r E

E

LTM

+ D

A o

r H

KE

D

DN

LE

U

Gro

ss/p

artia

l/bia

s N

o Pu

, Par

t of

Pu

mis

sing

, Pu

cont

ent b

ias

U/U

-235

con

tent

C

+ D

or

E

ELT

M +

DA

or

HK

ED

Irra

diat

ed

dire

cted

use

M

easu

red

disc

ards

, was

te

(WL

, WS)

Pu, D

NL

EU

G

ross

Pu

or

U m

issi

ng

Pu/U

rad

iatio

n H

M

MC

G, M

MC

N, M

MC

C,

DA

Spen

t fue

l (SF

) PU

, DN

LE

U

Gro

ss

Ass

embl

y re

plac

ed b

y du

mm

y, o

r m

issi

ng

Rad

iatio

n H

IC

VD

, FD

ET,

CPM

U,

HSG

M, S

FAT

Mat

eria

l cat

egor

y M

ain

stra

tum

M

ater

ial t

ype

com

pone

nts

Def

ect t

ype

Def

ect d

escr

iptio

n M

easu

rem

ents

re

quir

ed

App

licab

le

met

hods

R

ecom

men

ded

inst

rum

ents

Indi

rect

use

U

rani

um s

olut

ion

(SO

) D

NL

EU

G

ross

/par

tial/b

ias

No

U, P

art o

f U

m

issi

ng, U

C

onte

nt B

ias

U/U

-235

Con

tent

(B

or C) +

D

EB

AL

or

ELT

M +

DA

Ura

nium

pow

der

(PD

) D

LE

U

Gro

ss

No

U

U r

adia

tion

H

MM

CN

, MM

CG

, MM

CC

Pa

rtia

l Pa

rt o

f U

mis

sing

U

/U-2

35 c

onte

nt

B +

F

EB

AL

+ M

MC

N o

r (M

MC

G +

ULT

G)

LE

U

Bia

s U

con

tent

bia

s U

/U-2

35 c

onte

nt

B +

D

EB

AL

+ D

A

* A

: Ide

nti fi

catio

n (o

ptio

nally

usi

ng r

ando

m s

elec

tion)

B: W

eigh

ing

C

: Vol

ume

dete

rmin

atio

n

D: S

ampl

ing

and

anal

ysis

E: V

aria

bles

by

ND

A (

bias

def

ects

)

F: V

aria

bles

by

ND

A in

attr

ibut

e m

ode

(par

tial d

efec

ts)

G

: Cri

tical

ity c

heck

for

ver

i fi ca

tion

H

: Attr

ibut

e te

st b

y N

DA

(gr

oss

defe

cts)

M

: Fac

ility

spe

ci fi c

met

hod

for

in-p

roce

ss in

vent

ory

veri

fi cat

ion

42 J.-S. An

(5) Main Application Field of Veri fi cation Instruments (IAEA 2003d )

Name Full name Use

AWCC Active Well Coincidence Counter U/Pu measuring CEMO Continuous Enrichment Monitor CHEM Cascade Header Enrichment

Meter CPMU High-Range Underwater Monitor DA Destructive Analysis U/Pu measuring EBAL Facility Electronic Balance Sample weighing ELTM Electromanometer FDET Fork Detector Irrad. Fuel

Measurement Syste, Spent fuel veri fi cation

FRSC Rod Scanner (Facility) GBUV Gamma Burnup Veri fi er Pu measuring in spent fuel HCRS High Counter Rate System HKED Hybrid XRF/K-Edge Instrument U/Pu measuring HLNC High Level Neutron Coincidence

Counter Pu veri fi cation in vessel

HM-5 Hand-held Assay Probe U/Pu veri fi cation HRGS High Resolution Gamma

Spectrometer, generically refers to following equipment: SLNC, HRCS or MCRS

HSGM High Sensitivity Gamma Monitor U/Pu veri fi cation ICVD Improved Cerenkov Viewing

Device Spent fuel veri fi cation

INVS Inventory Sample Coincidence Counter

Pu veri fi cation

KEDG K-Edge Densitometer Pu concentration measuring in solution

LCBS Load-cell Based Weighing System for UF6 Cylinders

Weighing

MCRS Medium Count Rate System PD2O Densitometers PLBC Plutonium Bottle Counter MMCC Portable Multi-channel Analyzer

(PMCA) + CdTe Detector U measuring

MMCG PMCA + Ge Detector U measuring MMCN PMCA + NaI Detector U measuring PNCL Plutonium Neutron Coincidence

Counter Pu measuring in MOX

PSMC Plutonium Scrap Multiplicity Counter

Pu measuring

PWCC Passive Well Coincidence Counter

Pu measuring

SFAT Spent Fuel Attribute Tester U/Pu veri fi cation in spent fuel

ULTG Ultrasonic Thickness Gauge Cylinder thickness measure

(continued)

43Verifying the DPRK Nuclear Program

Name Full name Use

UNCL Neutron Coincidence Collar U measuring in new fuel UWCC Underwater Neutron Coincidence

Counter Pu measuring in MOX

UWTV Underwater TV Monitoring

(6) Analyze Environmental Samples to Detect Undeclared Facilities 7

Sample Detection nuclide Analysis method

Soil U-233/235/236/238, Pu-239/240, Cs-134/137, Sr-90, etc.

Titration, a , g -spectroscopy b -counting

Air Gas I-129/131, Kr-85, Gas-chromatography a , g -spectroscopy b -counting

Particle U-233/235/236/238, Pu-239/240, Cs-134/137 etc.

Liquid Solution I-129/131, Liquid-chromatography a , g -spectroscopy b -counting

Suspension U-233/235/236/238, Pu-239/240, Cs-134/137, etc.

Others (Flora, etc.) U-233/235/236/238, Pu-239/240, Cs-134/137, Sr-90, C-14, etc.

Gas-chromatography a , g -Spectroscopy b -counting titration

References

Gesh CJ (2004) A graphite isotope ratio method primer – a method for estimating plutonium pro-duction in graphite moderated reactors. PNNL-14568, Feb 2004, p 8

Hecker SS (2010) A return trip to North Korea’s Yongbyon Nuclear Complex. Center for International Security and Cooperation, Stanford University, Stanford, 20 Nov 2010

IAEA (2003a) IAEA safeguards manual SMC8, p 9 IAEA (2003b) IAEA safeguards manual SMC8, p 75 IAEA (2003c) IAEA safeguards manual SMC7, p 19 IAEA (2003d) IAEA Safeguards Manual SMC14 (2003) Annex 1, p 18 Reid BD, Morgan WC, Love EF Jr, Gerlach DC, Petersen SL, Livingston JV, Greenwood LR,

McNeece JP (1999) Graphite isotope ratio method development report: irradiation test demon-stration of uranium as a low fl uence indicator, PNNL-13056, p 11

(continued)

7 Summary from IAEA STR-348, Environmental Sampling for Safeguards, SGCP-PSA Inspection Measurement Quality Unit, September 2005.