Idaho National Laboratory 

Special Exposure Cohort

Petition Evaluation Report

SEC-00219 

Timothy D. Taulbee, PhD, CHP

Research Health Scientist

National Institute for Occupational Safety and Health (NIOSH)

Division of Compensation Analysis and Support (DCAS)

March 26, 2015

Richland, Washington
ORAU Evaluation Team

 W. Mitch Findley, Team Leader (ARA, CFA, Burial Ground)

 J. Michael Mahathy (Test Reactor Area)

 Jason Davis (Chemical Processing Plant)

 Brian Gleckler (Test Area North)

 Data Capture Support Team

• William Connell

• Jennifer Warner

• Art Gutzman

• Guy Babin

• Sally O’Neil
Petition Overview 

 Petitioner is an authorized representative for Energy 

Employee 

 Petition Received on July 8, 2014

 Petition Qualified on September 16, 2014

 Notification to Petitioner and ABRWH on January 20, 

2015 that NIOSH would exceed 180 day deadline due to 

site complexity and need for multiple data capture 

efforts onsite and at Federal Records Center in Seattle. 

 Evaluation Report sent to ABRWH on March 12, 2015

 Evaluation Report sent to Petitioner March 19, 2015 
Petition Overview cont.

 Preliminary Class: All employees who worked in any area 

of the Idaho National Laboratory from January 1, 1949 

through December 31, 1970

 Petitioner Basis: There was no internal monitoring for 

plutonium, neptunium, or fission products

 NIOSH qualified the petition based on limited monitoring 

for plutonium and neptunium. Current dose 

reconstruction method for plutonium is based on ratio 

from mixed fission products. 
Proposed Class Definition 

All employees of the Department of Energy, its predecessor 

agencies, and their contractors and subcontractors who 

worked at the Idaho National Laboratory in Scoville, Idaho, 

and were monitored for external radiation at the Idaho 

Chemical Processing Plant (CPP) (e.g., at least one film 

badge or TLD dosimeter from CPP) between January 1, 1963 

and December 31, 1974 for a number of work days 

aggregating at least 250 work days, occurring either solely 

under this employment, or in combination with work days 

within the parameters established for one or more other 

classes of employees in the Special Exposure Cohort.
INL Site Complexity

 Petition originally included both INL and ANL-W 

 Petition split November 25, 2014 due to DOE facility 

definitions. 

• INL operated 1949 - present

• ANL-W operated 1949 – 2005

 DCAS received new petition for ANL-W on December 4, 

2014 

 ANL-W Petition (SEC00224) is in qualification process 

 Current Evaluation (SEC00219) is for just INL facilities.
INL 

Operating 

Areas 
INL Operating Areas

1. Chemical Processing Plant (CPP)

2. Test Reactor Area (TRA)

3. Test Area North (TAN)

4. Misc. Reactor Areas (SPERT, ARA, OMRE)

5. Central Facilities Area (CFA)

6. Burial Grounds
Chemical Processing Plant (CPP) 

 Enriched Uranium (U235) Reprocessing Facility (601)

 Analytical Laboratories (602)

 Fuel Storage Building (603)

 Remote Analytical Facility (627)

 Solvent Burning Building

• Burning Used Solvent 

 Calcination Building (633)

• (Liquid waste conversion to solid waste)
Reprocessing Facility (601)

 Process 

make-up

 Operations 

corridor

 Sampling 

corridor

 Service 

corridor

 Access 

corridor
Reprocessing Facility (601)

 First Stage separation of mixed fission products

 Second and Third Stages separate remaining fission 

products and plutonium from uranium 

 Generally plutonium raffinate sent to waste tanks

 One campaign to separate plutonium and neptunium 

(1965-1972) 
Np and Pu Separations Campaign

 Np and Pu raffinate was stored in N Cell

 Took over 6 years to fill tank with enough solution to 

process 

 Activities during the six years

 Sampling Np and Pu concentration with each U235 

campaign

 Chemical separations experiments in Analytical Chemistry 

Laboratories (602) 

 Interview with Chemist indicated is was a short duration 

research as they pretty much knew how to separate and 

purify. 
Np and Pu Separations Campaign

 Processing was conducted during 3 week campaign in 

June 1972

• Solution pumped to P Cell for uranium extraction

• Solution pumped to J Cell with new piping for transfer to 

Multi-Curie Cell (MCC) for loading into 10 liter (L-10) bottles

• A total of 14 L-10 bottles were used thus the total solution 

was about 140 liters. 

• Total mass: Np = 5412g

 Pu = 544g

 U = 293g

 One worker did the physical transfer but several 

observed. 
Umpire Qualification Program

 Round-robin Testing of Analytical Chemistry Laboratories 

to resolve differences between shipping and receiving 

laboratories.

 CPP awarded contract to manage program in May 1965

• K-25 and CPP prepared uranium standards

• Rocky Flats and Hanford prepared plutonium standards

 Exposure potential during this program is minimal. 

Standards were received and simply shipped to other 

facilities for evaluation. 

 Several of the analytical laboratory personnel were 

monitored for plutonium exposure.
Degradation of Radiological Control 

In 1961, good 

control of 

contamination. 

All levels were 

less that 

Radiation Control 

Guidelines 20 

dpm for alpha 
Degradation of Radiological Control 

In 1963 there 

don’t appear to 

be severe 

contamination 

issues but perhaps 

the beginning of a 

slow degradation. 

(e.g. times when 

area is clean, 

times when area 

is contaminated.)
Degradation of Radiological Control 

In 1965 

contamination 

control is getting 

worse with levels 

near 100 times the 

RCG.

A 1968 audit 

indicates poor 

control of 

contamination and 

lack of surveys.
Degradation of Radiological Control 

 In 1970 widespread contamination throughout corridor
Degradation of Radiological Control

 November 1972, Plutonium intake in Analytical 

Laboratories 

• Contamination was found, bioassay follow-up was conducted

• One individual had a “different” Pu-238 to Pu-239 ratio 

indicating a previously unmonitored and undetected intake 

of plutonium.

• Incident report concluded that the intake occurred during a 

May 1972 cleaning of X Cell (six months prior).

• Survey logs of X cell indicate alpha contamination levels of a 

few thousand dpm after mopping. 
Degradation of Radiological Control 

 INL Committee formed to evaluate contamination 

control issues and recommend programmatic upgrades. 

• ACI-167 Preliminary ICPP Health Physics Upgrade Program 

Report issued October 1974
Degradation of Radiological Control 

ACI-167 Preliminary ICPP Health Physics Upgrade Program Report
Degradation of RadCon

ACI-167 Preliminary ICPP Health Physics Upgrade Program Report
CPP Recommendation

 Recommend SEC Class from January 1963 through 

December 1974

• Known alpha contamination in the Analytical Laboratories 

and processing cells in the 1963 time period. Very few 

workers monitored for plutonium exposure. 

• Potential for routine exposure to transuranic radionuclides 

during Np-Pu Campaign from 1965 to 1972.

• Degradation of Radiological Control Program beginning 

around 1963 that resulted in unmonitored plutonium 

exposures that were detected by chance during a second 

exposure incident.
CPP Recommendation

 Potential for exposure continued past 1970 initial 

evaluation period through at least the end of 1974 when 

the review committee published their report.

 NIOSH will continue to evaluate post 1974 years and may 

expand the class through the 83.14 process. 

 Somewhere between 1974 and the 1980s operations 

improved 

• Improved (increased) routine bioassay (fecal and urine)

• Significant effort to decontaminate facilities 
Test Reactor Area (TRA)

 Materials Test Reactor (MTR) 3/52 - 4/70

 Engineering Test Reactor Critical Facility 5/57 - 12/81 

 Engineering Test Reactor (ETR) 9/57 - 12/81

 Advanced Reactivity 

Measurement Facility No 1 

(ARMF-1) 10/60 - 12/74

 Advanced Reactivity 

Measurement Facility No 2 

(ARMF-2) 12/62 - 12/68

 Advanced Test Reactor Critical 

Facility 5/64 - present

 Advanced Test Reactor 

(ATR) 7/67 - present
Test Reactor Area – Other Facilities

 Neutron Chopper 

• Neutron cross-section measurements

 Gamma Spectroscopy Lab

• Operated next to MTR

• Scintillation Spectroscopy Catalog (IDO-16880 - Heath)

 Chemistry Labs

• Some exotic radionuclide separations

 Gamma Building 

• Co-60 Irradiations

 Alpha Hot Cell (Cave) 

• Operational around 1960
TRA Chemistry Laboratories 

 Over 200 exotic 

radionuclides have 

been identified as 

being produced in 

MTR and ETR

 Vast majority are 

beta/gamma emitters

 Some actinides 

produced and 

separated in alpha 

labs
TRA Recommendation

 Minimal potential for internal alpha exposure (few 

workers exposed to alpha materials)

 Internal exposures to airborne radionuclides were 

controlled by smear survey and continuous air sampling

 Plutonium and other actinide bioassay available for 

these few workers that we have identified as exposed 

 Actinide doses to workers at TRA can be reconstructed 

using individual bioassay. 

 Mixed Fission Product doses can be reconstructed, 

however, a co-worker model is needed for the post 1967 

time period
Whole Body Counting - 1963
Whole Body Counting - 1967

 Change from 

exposure potential 

based frequency to 

random of 1⁄4 of 

workforce per year

 Thus a co-worker 

model is needed to 

estimate exposure
Test Area North (TAN)

 Initial Engine Test (IET) 

• Heat Transfer Experiments (55-60)

• SNAPTRAN (64-66)

 TAN – Hot Shop (607)

 TAN – Actuator Building (615)

 Low Power Test Facility (LPT) 

• Cavity Reactor Critical Experiment (CRCE) (67-70)

• Critical Experiment Tank (CET) (58-62)

• Thermal Reactor Idaho Test (THRITS) 1964

 Shield Test Facility (STF)

• Shield Test Pool Facility (Susie) (early 1960s)
Test Area North

 Fission product and 

actinides not 

separated and appear 

to always be together
Test Area North – Hot Cell (633)

All alpha are 

accompanied 

with significant 

beta / gamma 

readings 
TAN Actuator Building (TAN-615)

 Actuator building was built in 1956 for testing prototype 

control mechanisms (control rods) for Initial engine 

Tests (IET).

 Sometime after 1961 was renamed to the TAN Fuel 

Handling Facility. 

 In 1963 during turnover to Phillips Petroleum Company 

building was found to be contaminated with uranium. 

 Reserved judgment on this facility until we can evaluate 

further. 
TAN Recommendation

 No appreciable exposure to actinides without mixed 

fission products.

 Actinide exposures can be bounded using a ratio to 

mixed fission product bioassay.

 Given the decrease in urinalysis and whole body count 

data in 1967-1970, we recommend development of a coworker model for mixed fission products. 

 NIOSH will prepare an addendum to Evaluation Report 

SEC00219 for the actuator building from 1961-1970. 
Misc. Reactor Areas

 Special Power Excursion Reactor Tests (SPERT)

• SPERT-1 (55-64)

• SPERT-2 (60-64)

• SPERT-3 (58-68)

• SPERT-4 (62-70)

 Auxiliary Reactor Area (ARA)

• ARA-1 (Hot Cell) (built in 1957)

• ARA-2 (Stationary Low Power , SL-1) (58-61)

• ARA-3 Gas Cooled Reactor Experiment (GCRE) (60-61)

• ARA-4 (Mobile Low Power , ML-1) (61-64)

 Organic Moderated Reactor Experiment (OMRE) (57-63) 
Special Power Excursion Tests

SPERT I - IV

 Investigate the safety of 

water cooled reactors

 Central Control point

 Personnel evacuated from 

area during operation

 CAMs on facility exhausts. 

 Health Physics involved in 

re-entry and small 

workforce was monitored
ARA Recommendation 

 SPERT – Dose Reconstruction is feasible since the is 

exposure is limited to mixed fission products and 

workers were monitored

 ARA II through IV –Dose Reconstruction is feasible since 

exposure is limited to mixed fission products

 OMRE – Dose Reconstruction is feasible since exposure 

is limited to mixed fission products

 ARA-I – Dose reconstruction is feasible with the 

possible exception of the 1968 Pa-233 work therefore 

1968 is reserved. 
Central Facilities - Laundry (CF-669)

 Clothing segregated by type and contamination level

 After cleaned and dried was monitored on special tables

• Each type had permissible contamination levels

• Any item over limit was rewashed

• After 30 to 90 day decay if Anti-C could not be 

decontaminated it was returned to facility for disposal

 Laundry had a radiation detector above receiving room 

door and a CAM in working area

 Room was evacuated if either alarmed
Burial Ground

 July 1952 – First Trench dug

 April 1954 – First shipment of Rocky Flats Waste 

 1957 First description of twice weekly pick-ups

 1957 First Burial Pit due to bulk items from Rocky Flats

 1958 Rocky Flats drums stacked by hand

 1961 Rocky Flats drums stacked using crane

 1963 Rocky Flats waste no longer stacked dumped

 1969 First retrieval of Pu drums from Rocky Flats

 1970 Burial of Pu waste discontinued
Burial Ground Monitoring

 Restricted access (Locked Gate)

 1959 memo indicates workers required to 

• Wear film badge at burial ground issued by Central Facilities

• Wear anti-contamination clothing (PPE)

• Work under a Safe Work Permit (SWP)

• Workers were monitored by Health Physics before leaving

 Health Physics was always present during dumping

 Air Sampling during drum dumping of Rocky Flats waste

 Radiological Surveys of Burial Ground
Burial Ground – Drum Retrieval

 Concern with initial drum 

retrieval.

 First effort was small – 

dozen or so drums for a 

few days.

 In 1971 larger effort was 

conducted. 

 Buildings were erected 

and continuous worker 

presence. 

 Need to further evaluate 

post 1968 period. Drum Retrieval from Pit 1 in 1969
Burial Ground - Recommendation

 Doses can be reconstructed for the period 1953 through 

1968. 

 NIOSH is uncertain about the 1969 Initial Drum Retrieval 

(IDR) and later operations through the 1980s.

 Reserving post 1968 period (1969 - ????) 

 NIOSH will prepare an addendum to Evaluation Report 

SEC00219 for 1969-1970. 

 NIOSH will evaluate post 1970 years and may expand the 

class through the 83.14 process. 
Feasibility Summary

49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

TRA

CPP

TAN

ARA

CFA

BG

 Can use area dosimeter badges to place workers at 

CPP during the 1963 to 1974 timeframe and therefore 

define the class.

 Light shaded green indicates the need for area specific 

co-worker model due to reduction in whole body 

counting. 
Feasibility Summary

Table 7-18: Summary of Feasibility Findings for SEC-00219

January 1, 1963 through December 31, 1974 (Chemical Processing Plant); 

January 1, 1949 through December 31, 1970 (INL site excluding CPP SEC class and reserved areas)

Source of Exposure

Chemical Processing Plant

Jan. 1, 1963 through Dec. 31, 1974

INL Site Excluding CPP SEC

Class and Reserved Areas

Jan. 1, 1949 through Dec. 31, 1970

Reconstruction 

Feasible

Reconstruction 

Not Feasible

Reconstruction 

Feasible

Reconstruction 

Not Feasible

Internal X X

 - Uranium (U) X X 

 - Neptunium (Np) X X 

 - Plutonium (Pu) X X 

 - Thorium (Th) X X 

 - Transuranic Radionuclides X X 

 - Fission products (MFP) X X 

 - Noble gases (Kr, Xe) X X 

 - Iodine (I) X X 

 - Tritium (H3) X X 

External X X

 - Gamma X X 

 - Beta X X 

 - Neutron X X 

 - Occupational Medical X-ray X X 
INL SEC Petition 00219—cont. 

 Health Endangerment

 Some workers in the class may have accumulated chronic 

radiation exposures through intakes of radionuclides at 

CPP.

 NIOSH is specifying that health may have been 

endangered for those workers monitored at CPP who 

were employed for a number of work days aggregating at 

least 250 work days.

 What about employees not included in the SEC?

• NIOSH intends to use monitoring data to conduct partial 

dose reconstructions for individuals not part of the SEC
Proposed Class

All employees of the Department of Energy, its predecessor 

agencies, and their contractors and subcontractors who 

worked at the Idaho National Laboratory in Scoville, Idaho, 

and were monitored for external radiation at the Idaho 

Chemical Processing Plant (CPP) (e.g., at least one film 

badge or TLD dosimeter from CPP) between January 1, 1963 

and December 31, 1974 for a number of work days 

aggregating at least 250 work days, occurring either solely 

under this employment, or in combination with work days 

within the parameters established for one or more other 

classes of employees in the Special Exposure Cohort.