Oak Ridge National Laborato

Special Exposure Cohort

Petition Evaluation Report

SEC‐00189

Timothy Taulbee, PhD, CHP

Research Health Scientist

National Institute for Occupational Safety and Health

Division of Compensation Analysis and Support

September 2012

Denver, CO
Special Exposure Cohort

Evaluation Team

 DCAS Lead – Timothy Taulbee

 ORAU SEC Lead – Mike Kubiak ORAU Lead Technical Evaluator – Mike Dom

• Roger Halsey• Keith Varnado• Ray Clark
Petition Overview

 83.13 petition received on July 18, 2011

 Petition qualified on October 11, 2011

 Notification to ABRWH on January 6, 2012 

NIOSH would exceed 180‐day deadline due 

data retrieval difficulties

 SEC Evaluation Report sent to ABRWH on A

22, 2012

 SEC Evaluation Report received by Petition

August 31, 2012
Petition Overview - cont.

 Petitioner requested class:

All contractor employees, subcontractoremployees, and AEC employees who were

monitored or should have been monitored 

any of the various radionuclides and fission

products present at the X‐10 plant while w

in all areas at the Oak Ridge National Labo(X‐10) from January 1, 1943 through Decem

31, 1952.
Petition Overview - cont.

 Class evaluated by NIOSH:

All employees of the Department of Energy

predecessor agencies, and their contractor

subcontractors who worked in any area at Oak Ridge National Laboratory (X‐10) in O

Ridge, Tennessee, from January 1, 1943 thJuly 31, 1955.
Proposed Class Definition

All employees of the Department of Energy, i

predecessor agencies, and their contractors a

subcontractors who worked in any area at thRidge National Laboratory (X‐10) in Oak Ridg

Tennessee, from June 17, 1943 through July 3

1955, for a number of work days aggregating least 250 work days, occurring either solely u

this employment, or in combination with wor

within the parameters established for one or 

other classes of employees in the Special Exp

Cohort.
Overview

 How did NIOSH develop this recommendatio

• ORNL Historical Background• Evaluation of Critical Exposure Issues

• Monitoring Data

• Feasibility of Dose Reconstruction
ORNL Historical Background

 Construction of X‐10 started in February 194

Bldg 205 - May 1943 

Bldg 105 – June 19

ORNL 
ORNL Background

 Reactor Critical on November 4, 1943

Bldgs. 105 and 205 – October 1943 ORNL Web site 2012
Start of Radiological Operatio

June 17, 1943

 Ground breaking February 1943

 Photographic evidence indicates constructio

June 1943

 First uranium slug shipment from Aluminum

Company of America (ALCOA) left on June 1

 Uranium stored somewhere onsite until bei

loaded into the graphite reactor around Oct

1943
Early ORNL Milestones

 Graphite Reactor Critical – November 4, 194 First discharge of irradiated uranium targets 

of November 1943

 1.54 mg of plutonium separated and sent to

University of Chicago – December 31, 1943

 First shipment of plutonium to Los Alamos i

February 1944

 By the end of war, 326.4 grams of plutonium 

been produced (1945)
ORNL Map ‐ 1955
Reactor Development

 1943 – Graphite reactor 1945 – Critical experiments in Bldg. 205 1949 – Low Intensity Test Reactor (LITR)

• Full scale mock‐up of the MTR reactor (INL)

 1950 – Bulk Shielding Reactor (BSR)

• Swimming pool style

 1952 – Homogeneous Reactor Experiment (H 1952 – Tower Shielding Experiment

 1953 – Aircraft Reactor Experiment
ORNL Reactors

LITR 

Tower Shielding Reactor 

Homogeneous Reactor Vessel (before installation and operation) Bulk Shielding Re
Isotope Production

 August 1946 ‐ First

radioisotopeshipment for medical

research

 First year of

production 60different isotopes

were shipped

Removal of first radioisotopes for medical 
Isotope Production







Main isotopes shipped wer

Y‐12 Connection

• Calutrons ‐ stable isotopes

• Cyclotron ‐ radioisotopes

Some separations

conducted at ORNL (X‐10)

e C‐14, P‐32, I‐13

Review 1992 
Uranium‐233 Production

 1944 ‐ Labscale preparation and testing of th

carbonate

 1946 – Research and Development for Uran

extraction (Thorium is the target material)

 1948 – Temproary pilot plant for thorium ex

built in 706HB

 1949 – Thorium extraction runs begin

 1954 – Thorex Pilot Plant installed in buildin

(3019)
Evaluation of Critical Exposure I

 Internal Dose

• Plutonium• Uranium• Mixed Fission Products

• Thorium• Exotic Radionuclides

 External Dose

• Beta / Gamma Monitoring• Neutrons
Internal Dose Monitoring

 Hierarchy of internal data

• Personal bioassay

—urine, feces, whole body count, chest count

• Personal breathing zone sampling

• Representative breathing zone sampling

• Surface contamination measurements

• Source term
Plutonium

 First plutonium monitoring data February 19 Urine samples sent to Argonne National Lab

(ANL) for analysis

 Several positive results could have resulted 

impure lanthanum carrier used in analysis

 Sampling and analysis improved over 6 mon

period
Plutonium– cont.

 Plutonium production operations ended in 1

however, research continued

Urine monitoringdecreasedsignificantly in 1946

but picked up in

1947 and increased

into the 1950s


Plutonium– cont.

 Approximately 1500 air samples are availab

1944 through 1947

 Sample descriptions indicate many were tak

from hood face

 Interviews with former workers indicate the

samplers were positioned at head height wi

intent of sampling the breathing zone

 Most samples were from 706 Radiochemistr

building (i.e. research)
Plutonium– cont.

 Based on availability of plutonium bioassay 

results in conjunction with alpha air sample 

from research facilities, dose reconstruction 

plutonium exposures is believed to be feasib
Uranium

 NIOSH has not located any uranium bioassa

until 1949

 A 1949 plutonium bioassay logbook indicate

sample split and a co‐analysis for Uranium‐2
Uranium– cont.

 According to a 1954 review of the urinalysis

program, ORNL began processing plutonium 

uranium urinalysis onsite in 1947

 NIOSH has not located any uranium urinalys

results before 1949
Uranium (Air Sample) – cont.

 Majority (80%) of 1944‐1947 air sample data 

radiochemistry building (706)

 Limited data (8%) from separations facility 

where plutonium was separated from uranimixed fission products

 NIOSH found a few air sample logsheets atta

correspondence indicating a routine air mon

program
Uranium– cont.

 Interviews with former workers confirmed r

air monitoring program

 Monthly reports also indicate a routine air

monitoring program and report number of s

collected

• (≈ 60 samples per week in 1948 = 3000 per year)
Uranium– cont.

 To date, neither NIOSH nor DOE has been ab

locate these air sample results through exha

records searches

 As a result, NIOSH finds that reconstruction 

internal doses to uranium is infeasible from 

1943 through December 31 1948
Mixed Fission Products

 No mixed fission product bioassay has been 

until 1950
Mixed Fission Products – cont

 1954 review of urinalysis program indicated 

the capability to monitor for mixed fission p

was developed in 1949

 In August 1949 ORNL‐368 Procedure for the

radiochemical analysis of barium, strontium

rare earths was published

 Some very limited incident based sampling w

conducted in 1949 based weekly and month

reports
Mixed Fission Products – cont

 Difficulties with obtaining fission product sa

and request methodology appears to have cin 1951 resulting in more robust monitoring

program

 Most of the air sampling data was for produ

contamination in the air (alpha)

 Limited air sampling data for beta/gamma e
Mixed Fission Products – cont

 Limited data for separations facility (205), m

sample data was for Radiochemistry Buildin

 Evidence indicates no bioassay program for 

fission products until late 1949

 Limited air sample data for separations facil
Mixed Fission Products – cont

 NIOSH finds that reconstruction of internal d

mixed fission products is infeasible from Jun

1943 through December 31, 1949

 NIOSH believes that dose reconstruction fro

January 1, 1950 through July 31, 1955 may bfeasible
Thorium

 ORNL began conducting research involving t

in 1944

 Most of the early research was conducted in 

radiochemistry building (706) where NIOSH 

located extensive alpha air sample results

 NIOSH has confirmed through records and

interviews that these air sample results are

representative of a worker’s breathing zone 

chemistry laboratory environment
Thorium– cont.

 However, NIOSH has only been able to locat

sample data from 1944 through 1947

 No air sample data post 1947 has been locat As discussed in the uranium section, a routin

monitoring program was conducted, but nei

NIOSH nor DOE has been able to locate the 
Thorium– cont.

 NIOSH has not been able to locate any thori

bioassay prior to August 1955

 Generally urinalysis for thorium results in a 

dose that has been characterized as insuffic

accurate

 At ORNL, however, thorium was monitored 

analysis

 NIOSH has obtained thorium fecal results fo

workers starting in August 1955
Thorium– cont.

 Uranium‐233 separations increased significa

upon receipt of irradiated thorium from the

Savannah River site in 1956 and 1957

 Following receipt of this irradiated thorium, 

ORNL bioassay program also increase
Thorium– cont.

 Due to extensive representative air samples 

from 1944 through 1947, NIOSH believes dosreconstruction for thorium exposure may be 

 Due to the lack of air sample data from 1948 

July 1955, NIOSH finds that dose reconstruct

thorium exposure is infeasible

 Due to availability of thorium fecal samples i

1955, NIOSH believes that dose reconstructio

thorium exposures may be feasible
Exotic Radionuclides – cont.

 Starting in 1944 ORNL began producing polo

210 (Dayton Labs) and lanthanum‐140 (LAN

 By 1946, ORNL also produced C‐14, P‐32, I‐1

 By 1948 hundreds of isotopes were being pr

and there was a special Isotopes ProductionDivision at ORNL

 Based on NIOSH’s research to date, this divi

appears to have operated the calutrons and 

cyclotron at Y‐12
Exotic Radionuclides – cont.
Exotic Radionuclides – cont.

 NIOSH initiated an 83.14 evaluation of isoto

productions from the cyclotron and calutron

Y‐12 facility in March 2012

 The ORNL SEC‐00189 team began to evaluat

radionuclides were produced and separated 

ORNL; we discovered that there was significoverlap in research

 Table 5‐3 and Table 5‐4 lists isotope product

NIOSH has found to date
Exotic Radionuclides – cont.

 Due to resource overlap, NIOSH decided to R

the exotic radionuclide evaluation at ORNL acombine with the Y‐12 83.14 effort once SECwas completed and presented

 On August 30, 2012 NIOSH/ORAUT had a kic

meeting for this combined effort

 NIOSH will update the ABRWH as we progre

our evaluation
Internal Dose Monitoring

 Summary of internal monitoring data

Internal Sources

Year

43 44 45 46 47 48 49 50 51 52 53 

Plutonium Air Bio Air Bioassay

Uranium No Data BioassayThorium Air Data No DataFission Products No Data Bioassay

ExoticRadionuclides Reserved for a joint ORNL (X‐10) and Y‐12 evalua

 Overall internal dose reconstruction is infeas

from June 17, 1943 through July 31, 1955
External Monitoring

 Beta – Gamma

• Pocket Ionization Chambers

—12721 readings – December 1943

• Film Badge Dosimeters

 Neutron

• 1944 – Neutron / Photon Surveys

• 1947 – Special Fine Grain Films

• 1949 – NTA
External Beta / Gamma Monito

Number of External Records by Year in Exposure Database

Year Record Count No. of Na

1943 1345 857

1944 4117 2106

1945 2946 17471946 2674 17991947 3215 22661948 3793 25841949 2516 20391950 3442 25991951 4174 30861952 4355 32711953 3953 31581954 4536 33361955 4536 3471

‐‐‐ Total = 46,928 ‐‐‐
Neutron Monitoring

 Cadmium filtered neutron badge Capability for both thermal and fast neutron

• Used 14N(neutron,proton)14C reaction for therm

neutron response (584 keV proton)

• Thermal response of neutron dosimeter calibrat

a thermal column from the graphite reactor

 1947 studies of track fading by Joseph Check
Other Neutron Monitoring Da

 Graphite Reactor

• Neutron / photon surveys

 Low Intensity Test Reactor (LITR)

• Full scale mockup of MTR and neutron / photon 

of MTR indicate a NP ratio of 0.58

 Bulk Shielding Reactor (BSR)

• Typically zero 20 feet of water

• Experiments lowered into pool

• Neutron / photon surveys
Other Neutron Monitoring Data 

 Homogeneous Reactor Experiment (HRE)

• Confirmed workers at HRE wore neutron dosime

through review of claimant files

 Aircraft Reactor Experiment (ARE)

• Neutron / photon surveys

 Tower Shielding Reactor (TSR)

• Neutron / photon surveys

• Neutron spectra
External Dose Summary

 Beta / Gamma Exposures

• Pocket ionization chambers and film badge data

 Neutron Exposures

• Neutron / photon surveys

• Neutron dosimeter (thermal and fast capability)

 Due to use and availability of pocket ionizat

chamber data, film badge dosimetry, neutro

surveys, and neutron dosimetry, NIOSH beli

external dose reconstruction is feasible
Conclusion from Research

 NIOSH has evaluated the available inform

and determined that it does not have acc

sufficient personnel monitoring, workpla

monitoring, or source‐term data to suffic

estimate potential internal exposures to:

• Uranium: June 17, 1943 – December 31, 1948

• Fission Products: June 17, 1943 – December 3

• Thorium: January 1, 1948 – July 31, 1955

 Combined infeasibility

• June 17, 1943 through July 31, 1955
ORNL SEC Petition 00189—con

 Why everyone?

• Unlike other large facilities (Savannah River, Ida

was a relatively small main campus. The main ca

about the same size as the 700/300 area at Sava

River. The facility was largely open once you ent

through the guard checkpoints. NIOSH could not 

practical way to identify the uranium, mixed fiss

product, and thorium exposed workers. Organiz

charts could really only identify likely exposed w

based on job title and organizational function.
ORNL SEC Petition 00189—con

 What about employees not included in the S

• NIOSH intends to use any internal and external

monitoring data, and medical doses that may beavailable for an individual claim (and that can be

interpreted using existing dose reconstruction p

or procedures). Therefore, partial dose reconstrufor individuals employed at Oak Ridge National

Laboratory during the period from June 17, 194

July 31, 1955, but who do not qualify for inclusio

Special Exposure Cohort, may be performed usindata as appropriate.
Health Endangerment

 The evidence reviewed in this evaluation

indicates that some workers in the class m

have accumulated chronic radiation expos

through intakes of radionuclides and direc

exposure to radioactive materials.

 Consequently, NIOSH is specifying that hea

may have been endangered for those work

covered by this evaluation who were empl

for a number of work days aggregating at l

250 work days within the parameters

established for this class or in combination 

work days within the parameters establish

one or more other classes of employees in 

SEC.
Proposed Class

All employees of the Department of Energy, i

predecessor agencies, and their contractors a

subcontractors who worked in any area at thRidge National Laboratory (X‐10) in Oak Ridg

Tennessee, from June 17, 1943 through July 3

1955, for a number of work days aggregating least 250 work days, occurring either solely u

this employment, or in combination with wor

within the parameters established for one or 

other classes of employees in the Special Exp

Cohort.
Feasibility Summary

Feasibility Findings for Oak Ridge National Laboratory (X

SEC Petition SEC‐00189 (January 1943 – July 1955)

Source of Exposure Reconstruction

Feasible

Reconstruc

Feasi

Internal

‐ Plutonium X

‐ Uranium Jan 49 – Jul 55 Jun 43 – 

‐ Thorium Jan 44 – Dec 47 Jan 48 – ‐ Fission Products Jan 50 – Jul 55 Jan 44 – 

‐ Exotic Radionuclides Reserved Reser

External

‐ Beta‐gamma X

‐ Neutron X

‐ Occupational Medical X‐ray X
Feasibility Summary
Claimant Statistics

(July 10, 2012)

 Total number of ORNL claims submitted: 

 Total number claims with employment in

proposed class: 

• Number of dose reconstructions completed 

• Number of claims for which internal dosimetry

records in the proposed class 

• Number of claims for which external dosimetry

records in the proposed class 
Questions