SEC Petition Evaluation Report 

Petition SEC-00186 

Report Rev #: 0 Report Submittal Date: July 18, 2011

Subject Expert(s): Jason Davis 

Site Expert(s): N/A 

Petitioner Administrative Summary 

Petition Under Evaluation 

Petition # Petition 

Type 

Petition A 

Receipt Date DOE/AWE Facility Name 

SEC-00186 83.14 April 22, 2011 Y-12 Plant

NIOSH-Proposed Class Definition 

All employees of the Department of Energy, its predecessor agencies, and their contractors and subcontractors 

who worked at the Y-12 facility in Oak Ridge, Tennessee, during the period from January 1, 1948 through 

December 31, 1957, 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. 

Related Petition Summary Information 

SEC Petition 

Tracking #(s) 

Petition 

Type 

DOE/AWE 

Facility Name Petition Status 

SEC-00018 

SEC-00026 

SEC-00028 

SEC-00098

83.13 

83.13 

83.13 

83.14 

Y-12 Plant 

Y-12 Plant 

Y-12 Plant 

Y-12 Plant 

Class added to the SEC: Mar 1943 through Dec 1947 

Merged with SEC-00018 

Class added to the SEC: Jan 1948 through Dec 1957 

(for workers in specified areas of the Y-12 site) 

Class added to the SEC: Mar 1, 1943 through Dec 31, 1947 

Related Evaluation Report Information 

Report Title DOE/AWE 

Facility Name 

SEC Petition Evaluation Report for Petition SEC-00018 (merged with SEC-00026) 

SEC Petition Evaluation Report (and Supplement) for Petition SEC-00028 

SEC Petition Evaluation Report for Petition SEC-00098

Y-12 Plant 

Y-12 Plant 

Y-12 Plant

ORAU Lead Technical Evaluator: Jason Davis ORAU Peer Review Completed By: Michael Kubiak 

Peer Review Completed By: [Signature on file] 7/18/2011 

Lara Hughes Date 

SEC Petition Evaluation Reviewed By: [Signature on file] 7/19/2011 

J. W. Neton Date 

SEC Evaluation Approved By: [Signature on file] 7/19/2011 

Stuart L. Hinnefeld Date 
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Evaluation Report Summary: SEC-00186, Y-12 Plant 

This evaluation report by the National Institute for Occupational Safety and Health (NIOSH) 

addresses a class of employees proposed for addition to the Special Exposure Cohort (SEC) per the 

Energy Employees Occupational Illness Compensation Program Act of 2000, as amended, 42 U.S.C. 

§ 7384 et seq. (EEOICPA) and 42 C.F.R. pt. 83, Procedures for Designating Classes of Employees 

as Members of the Special Exposure Cohort Under the Energy Employees Occupational Illness 

Compensation Program Act of 2000. 

NIOSH-Proposed Class Definition

All employees of the Department of Energy, its predecessor agencies, and their contractors and 

subcontractors who worked at Y-12 Plant in Oak Ridge, Tennessee, from January 1, 1948 through 

December 31, 1957, 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 included in the Special Exposure Cohort. 

The intent of this evaluation is to address consistency and implementation issues associated with 

previous Y-12 Special Exposure Cohort evaluations, specifically SEC-00028. Many of the class 

definitions in the earlier SEC evaluations were based on petitioner-requested wording, which caused 

an obvious variance in class definitions. A recent review of existing SEC class definitions evaluated 

criteria such as consistency, applicability and whether any class definitions needed to be corrected by 

NIOSH (NIOSH 2010). In this review NIOSH determined that the class definition as set forth in SEC00028 needed revising, because problems existed with the implementation of the previous class. In 

addition, through the course of ongoing dose reconstruction and research, NIOSH has determined that, 

due to undocumented worker movements across the site, limited claimant-specific information 

pertaining to work locations, and a determination by the Department of Labor (DOL) that employment 

records do not indicate work locations, NIOSH is unable to eliminate any specific worker from 

potential exposure scenarios based on assigned work location. NIOSH has found that a determination 

cannot always be made as to the specific area an employee worked in, or whether an employee should 

have been monitored for radiological exposures. Accordingly, NIOSH has determined that it is 

necessary to remove the area-specific and monitoring criteria from the class description associated 

with SEC-00028 thorium and cyclotron exposures for the period from January 1, 1948 through 

December 31, 1957. As such, NIOSH has determined that is also necessary to expand the SEC class 

definition to include all areas of the Y-12 Plant, and all employees of DOE, its predecessor agencies, 

and their contractors and subcontractors who worked at the Y-12 Plant during the period from January 

1, 1948 through December 31, 1957. The SEC-00186 evaluation recommends a class that is 

consistent with current DCAS methods for defining a recommended SEC class. 

Feasibility of Dose Reconstruction Findings

NIOSH lacks sufficient information, which includes biological monitoring data, sufficient air 

monitoring data, or sufficient process and radiological source term information, to allow it to estimate 

with sufficient accuracy the potential internal exposures to radionuclides associated with cyclotron 

operations, or to thorium and its progeny, to which the proposed class may have been subjected. 

The NIOSH dose reconstruction feasibility findings are based on the following: 
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• Principal sources of internal and external radiation for members of the proposed class included 

exposures to uranium and thorium and their decay progeny as well as various radionuclides 

produced as a result of cyclotron operations. 

• NIOSH previously determined in its evaluation of petition SEC-00028 that it did not locate 

sufficient data, including bioassay results, ambient air concentrations, or process information to 

estimate with sufficient accuracy internal exposures to thorium for workers in several of the Y-12 

buildings (Buildings 9201-3, 9202, 9204-1, 9204-3, 9206, and 9212). In addition, NIOSH did not 

locate sufficient data, including bioassay results, ambient air concentrations, or process 

information to estimate with sufficient accuracy internal exposures to radionuclides for workers in 

the cyclotron area of the Y-12 Plant (Building 9201-2). In 2006, DHHS designated the following 

class for inclusion in the SEC: 

Department of Energy (DOE) employees or DOE contractor or subcontractor employees who 

were monitored or should have been monitored for: thorium exposures while working in Building 

9201-3, 9202, 9204-1, 9204-3, 9206, or 9212 at Y-12 for a number of work days aggregating at 

least 250 work days from January 1948 through December 1957, or in combination with work 

days within the parameters established for one or more classes of employees in the SEC; or 

radionuclide exposures associated with cyclotron operations in Building 9201-2 at Y -12 for a 

number of work days aggregating at least 250 work days from January 1948 through December 

1957, or in combination with work days within the parameters established for one or more classes 

of employees in the SEC (HHS, 2006).

• NIOSH found that internal exposure could be reconstructed for all employees between January 

1948 and December 31, 1957, with the exception of internal exposure to thorium and cyclotron 

radionuclides, as determined in the evaluation of SEC-00028. 

• NIOSH found that external exposure, including occupational medical doses, could be 

reconstructed for all employees between January 1948 and December 31, 1957, as determined in 

the evaluation of SEC-00028. 

• Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is insufficient information to 

either: (1) estimate the maximum radiation dose, for every type of cancer for which radiation 

doses are reconstructed, that could have been incurred under plausible circumstances by any 

member of the class; or (2) estimate the radiation doses of members of the class more precisely 

than a maximum dose estimate. 

Although NIOSH found that it is not possible to completely reconstruct radiation doses for the 

proposed class, NIOSH intends to use any internal and external monitoring data that may become 

available for an individual claim (and that can be interpreted using existing NIOSH dose 

reconstruction processes or procedures). Therefore, dose reconstructions for individuals employed at 

Y-12 Plant during the period from January 1, 1948 through December 31, 1957, but who do not 

qualify for inclusion in the SEC, may be performed using these data as appropriate. 
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Health Endangerment Determination

The NIOSH evaluation did not identify any evidence supplied by the petitioners or from other 

resources that would establish that the class was exposed to radiation during a discrete incident likely 

to have involved exceptionally high-level exposures, such as nuclear criticality incidents or other 

events involving similarly high levels of exposures. However, the evidence reviewed in this 

evaluation indicates that some workers in the class may have accumulated chronic radiation exposures 

through intakes of uranium and thorium and their decay progeny as well as various radionuclides 

produced as a result of cyclotron operations. Therefore, 42 C.F.R. § 83.13(c)(3)(ii) requires NIOSH 

to specify that health may have been endangered for those workers covered by this evaluation who 

were employed for a number of work days aggregating at least 250 work days within the parameters 

established for this class or in combination with work days within the parameters established for one 

or more other classes of employees in the SEC. 
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Table of Contents 

1.0 Purpose and Scope ....................................................................................................................... 9

2.0 Introduction ................................................................................................................................. 9

3.0 NIOSH-Proposed Class Definition and Petition Basis .............................................................. 10

4.0 Radiological Operations Relevant to the Proposed Class ......................................................... 11

4.1 Operations Description ..................................................................................................... 11

4.1.1 Y-12 Key Uranium Processes .............................................................................. 12

4.1.2 Y-12 Lithium Isotope Separation Process ............................................................ 13

4.1.3 Y-12 Thorium Studies .......................................................................................... 14

4.1.4 Y-12 Waste Disposal in the S-3 and New Hope Ponds ........................................ 15

4.1.5 ORNL and Non-Uranium Activities at Y-12 ....................................................... 16

4.1.6 Weapons Assembly and Disassembly .................................................................. 17

4.2 Radiation Exposure Potential from Operations ................................................................ 18

4.2.1 Alpha Particle Emissions ...................................................................................... 18

4.2.2 Beta/Photon Radiation Fields ............................................................................... 19

4.2.3 Neutron Sources ................................................................................................... 21

4.2.5 Recycled Uranium and Other Radionuclides of Concern .................................... 22

4.3 Time Period Associated with Radiological Operations .................................................... 23

4.4 Site Locations Associated with Radiological Operations ................................................ 23

4.5 Job Descriptions Affected by Radiological Operations ................................................... 23

5.0 Summary of Available Monitoring Data for the Proposed Class .............................................. 23

5.1 Data Capture Efforts and Sources Reviewed ................................................................... 24

5.2 Worker Interviews ............................................................................................................ 24

5.3 Internal Personnel Monitoring Data ................................................................................. 25

5.4 External Personnel Monitoring Data ................................................................................ 27

5.5 Workplace Monitoring Data ............................................................................................. 28

5.6 Radiological Source Term Data ....................................................................................... 29

6.0 Feasibility of Dose Reconstruction for the Proposed Class ...................................................... 29

6.1 Feasibility of Estimating Internal Exposures ................................................................... 30

6.2 Feasibility of Estimating External Exposures .................................................................. 31

6.3 Class Parameters Associated with Infeasibility ................................................................ 32

7.0 Summary of Feasibility Findings for Petition SEC-00186 ........................................................ 32

8.0 Evaluation of Health Endangerment for Petition SEC-00186 ................................................... 33

9.0 NIOSH-Proposed Class for Petition SEC-00186 ...................................................................... 34

10.0 Evaluation of Second Similar Class .......................................................................................... 34
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11.0 References ................................................................................................................................. 35

Attachment 1: Data Capture Synopsis ................................................................................................... 41

Attachment 2: Stable and Radioactive Isotopes Produced and/or Separated and Purified at Y-12 ...... 53

Tables 

4-1: Key Uranium Operations ............................................................................................................... 12

4-2: Chronology of Lithium Production Operations ............................................................................. 14

4-3: Thorium Decay Chain Alpha Emissions ........................................................................................ 19

4-4: Beta and Photon Energies .............................................................................................................. 20

4-5: Neutron Sources used at the Y-12 Plant ........................................................................................ 21

4-6: Neutron Data for Commonly-used Neutron Sources ..................................................................... 21

5-1: Summary of Available Y-12 Uranium Urinalysis Data (1948-1960) ........................................... 25

5-2: Non-Uranium Bioassay Results from Delta View ......................................................................... 26

5-3: Summary of Available Monitoring Data for Y-12 Workers (1948-1960) ..................................... 28

5-4: Summary of Available Uranium Air Monitoring Data for Y-12 Workers (1948-1960) .............. 29
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SEC Petition Evaluation Report for SEC-00186

ATTRIBUTION AND ANNOTATION: This is a single-author document. All conclusions drawn from 

the data presented in this evaluation were made by the ORAU Team Lead Technical Evaluator: Jason 

Davis, Oak Ridge Associated Universities. The rationales for all conclusions in this document are 

explained in the associated text. 

1.0 Purpose and Scope 

This report evaluates the feasibility of reconstructing doses for employees who worked at the Y-12 

Plant during a specified time. It provides information and analysis germane to considering a petition 

for adding a class of employees to the Congressionally-created SEC. 

This report does not make any determinations concerning the feasibility of dose reconstruction that 

necessarily apply to any individual energy employee who might require a dose reconstruction from 

NIOSH, with the exception of the employee whose dose reconstruction could not be completed, and 

whose claim consequently led to this petition evaluation. The finding in this report is not the final 

determination as to whether or not the proposed class will be added to the SEC. This report will be 

considered by the Advisory Board on Radiation and Worker Health (the Board) and by the Secretary 

of Health and Human Services (HHS). The Secretary of HHS will make final decisions concerning 

whether or not to add one or more classes to the SEC in response to the petition addressed by this 

report. 

This evaluation, in which NIOSH provides its findings both on the feasibility of estimating radiation 

doses of members of this class with sufficient accuracy and on health endangerment, was conducted in 

accordance with the requirements of EEOICPA and 42 C.F.R. § 83.14. 

2.0 Introduction 

Both EEOICPA and 42 C.F.R. pt. 83 require NIOSH to evaluate qualified petitions requesting that the 

Department of Health and Human Services add a class of employees to the SEC. The evaluation is 

intended to provide a fair, science-based determination of whether it is feasible to estimate, with 

sufficient accuracy, the radiation doses of the proposed class of employees through NIOSH dose 

reconstructions.1

NIOSH is required to document its evaluation in a report, and to do so, relies upon both its own dose 

reconstruction expertise as well as technical support from its contractor, Oak Ridge Associated 

Universities (ORAU). Once completed, NIOSH provides the report to both the petitioners and the 

Advisory Board on Radiation and Worker Health. The Board will consider the NIOSH evaluation 

report, together with the petition, comments of the petitioner(s) and such other information as the 

Board considers appropriate, to make recommendations to the Secretary of HHS on whether or not to 

add one or more classes of employees to the SEC. Once NIOSH has received and considered the 

advice of the Board, the Director of NIOSH will propose a decision on behalf of HHS. The Secretary 

 

1

 NIOSH dose reconstructions under EEOICPA are performed using the methods promulgated under 42 C.F.R. pt. 82 and 

the detailed implementation guidelines available at http://www.cdc.gov/niosh/ocas. 
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of HHS will make the final decision, taking into account the NIOSH evaluation, the advice of the 

Board, and the proposed decision issued by NIOSH. As part of this final decision process, the 

petitioner(s) may seek a review of certain types of final decisions issued by the Secretary of HHS.2

3.0 NIOSH-Proposed Class Definition and Petition Basis 

The NIOSH-proposed class includes all employees of the Department of Energy, its predecessor 

agencies, and DOE contractors or subcontractors who worked at the Y-12 facility in Oak Ridge, 

Tennessee during the period from January 1, 1948 through December 31, 1957, 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. During this period, employees at this facility were 

involved primarily in the processing of uranium for the production of nuclear weapons components 

and test devices. 

The evaluation responds to Petition SEC-00186 which was submitted by an EEOICPA claimant 

whose dose reconstruction could not be completed by NIOSH due to a lack of sufficient dosimetryrelated information. NIOSH’s determination that it is unable to complete a dose reconstruction for an 

EEOICPA claimant is a qualified basis for submitting an SEC petition pursuant to 42 C.F.R. § 

83.9(b). 

There is currently one class of Y-12 workers associated with the previous NIOSH evaluation of SEC 

petition SEC-00028 (NIOSH, 2006a; NIOSH 2006b), for which the Secretary of Health and Human 

Services (HHS) has designated for inclusion in the Special Exposure Cohort: 

Class added to the SEC effective September 7, 2006 (HHS, 2006): Department of Energy (DOE) 

employees or DOE contractor or subcontractor employees who were monitored or should have 

been monitored for thorium exposures while working in Building 9201-3, 9202, 9204-1, 9204-3, 

9206, or 9212 at Y-12 for a number of work days aggregating at least 250 work days from January 

1948 through December 1957, or in combination with work days within the parameters (excluding 

aggregate work day requirements) established for one or more classes of employees in the SEC; or 

radionuclide exposures associated with cyclotron operations in Building 9201-2 at Y -12 for a 

number of work days aggregating at least 250 work days from January 1948 through December 

1957, or in combination with work days within the parameters (excluding aggregate work day 

requirements) established for one or more classes of employees in the SEC. 

A recent review of existing SEC class definitions evaluated criteria such as consistency, applicability 

and whether any class definitions needed to be corrected by NIOSH (NIOSH 2010). In this review 

NIOSH determined that the class definition as defined in SEC-0028 needed revising, because 

problems existed with the implementation of the previous class. In addition, through the course of 

ongoing dose reconstruction and research, NIOSH has determined that, due to undocumented worker 

movements across the site, limited claimant-specific information pertaining to work locations, and a 

determination by the Department of Labor (DOL) that employment records do not indicate work 

 

2

 See 42 C.F.R. pt. 83 for a full description of the procedures summarized here. Additional internal procedures are 

available at http://www.cdc.gov/niosh/ocas. 
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locations, NIOSH is unable to eliminate any specific worker from potential exposure scenarios based 

on assigned work location. NIOSH has found that a determination cannot always be made as to the 

specific area an employee worked in, or whether an employee should have been monitored for 

radiological exposures. Accordingly, NIOSH has determined that it is necessary to remove the areaspecific and monitoring criteria from the class description associated with SEC-00028 thorium and 

cyclotron exposures for the period from January 1, 1948 through December 31, 1957. As such, 

NIOSH has determined that is also necessary to expand the SEC class definition to include all areas of 

the Y-12 Plant, and all employees of DOE, its predecessor agencies, and their contractors and 

subcontractors who worked at the Y-12 Plant during the period from January 1, 1948 through 

December 31, 1957. The SEC-00186 evaluation recommends a class that is consistent with current 

DCAS methods for defining a recommended SEC class. 

4.0 Radiological Operations Relevant to the Proposed Class 

The following subsections summarize the radiological operations at the Y-12 Plant from January 1, 

1948 through December 31, 1957 and the information available to NIOSH to characterize particular 

processes and radioactive source materials. Using available sources, NIOSH has attempted to gather 

process and source descriptions, information regarding the identity and quantities of radionuclides of 

concern, and information describing processes through which the radiation exposures of concern may 

have occurred and the physical environment in which they may have occurred. The information 

included within this evaluation report is meant only to be a summary of the available information. 

4.1 Operations Description 

The Y-12 Plant is located in Oak Ridge, Tennessee on an 811-acre (0.67 miles wide and 3.2 miles 

long) site. For the period under evaluation by NIOSH, the Y-12 Plant workforce ranged from 2,511 

employees in 1948 to 5,169 workers in 1957 with a peak employment of 5,817 workers in 1954 

(NIOSH, 2006a, Table 6-2). 

Using an electromagnetic separation process within a calutron, the original mission of Y-12 was to 

separate fissionable isotopes of uranium (U-235) from uranium feedstock for use in the Hiroshima 

atomic bomb. Radiological operations, processes, and dose reconstruction information relevant to this 

specific uranium enrichment work is covered in a separate report: SEC Petition Evaluation Report 

SEC-00018 (NIOSH, 2005). 

While the SEC-00018 and SEC-00098 reports evaluate the years 1943 through 1947 (NIOSH 2005; 

NIOSH 2008), the previous SEC-00028 evaluation (NIOSH, 2006a; NIOSH, 2006b), and this current 

SEC-00186 evaluation focus on a time period that falls within what is generally described as the 

"second era" of Y-12 operational history. The electromagnetic separation process for U-235 

enrichment (calutrons) was discontinued in 1947 in favor of the more-efficient gaseous diffusion 

process. Extending from 1947 through 1992, the second era’s primary mission was the production of 

key components of nuclear weapons and test devices. During this era, the vast majority of the work at 

Y-l2 involved uranium processing, although other radioactive materials such as thorium, tritium, 

polonium, and transuranics were also present in very small quantities during the period under 

evaluation. During the 1948 through 1957 period, the Y -12 operating contractors were Carbide and 
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Carbon Chemicals and Union Carbide Nuclear Company, both divisions of Union Carbide 

Corporation predecessor companies (Oak Ridge, 1993, pdf p. 174). 

Y-12 Plant operations included the following functional areas: 

• Key Uranium Processes 

• Lithium Isotope Separation Process 

• Thorium Studies 

• Waste Disposal in the S-3 and New Hope Ponds 

• Oak Ridge National Laboratory (ORNL) and Non-Uranium Activities 

4.1.1 Y-12 Key Uranium Processes 

Table 4-1 summarizes the key uranium processes, buildings, and dates of operation (Oak Ridge, 1999, 

pdf p. 171). 

Table 4-1: Key Uranium Operations 

(This table spans two pages) 

Key Uranium Operations Buildings Involved Dates of 

Operation 

Uranium recovery and Recycle: Y-12 stopped enriching uranium after 

WWII and operations centered on uranium recovery and recycling of 

residual uranium found on equipment and scrap material. Operations 

included mechanical scraping and brushing, nitric-acid washing, and 

distillation and recovery of solid uranium compounds adhered to 

surfaces. Uranium-contaminated materials included condensates, 

scrubber solutions, raffinates, destructive distillates, oils, and 

miscellaneous residues. These Y-12 facilities handled mostly normal 

uranium and depleted uranium. 

9202, 9203, 9206, 9212: 

• 9202, 9203 received 

depleted uranium, slightly 

enriched uranium, and 

normal uranium. 

• 9206 was the main uranium 

recovery and recycle facility 

and housed sanding, 

grinding, chemistry, and 

incinerator operations. 

• 9212 housed the largest 

chemical operations for 

enriched uranium 

purification, recovery, and 

chemical conversion as well 

as normal and depleted 

uranium-machining 

operations. 

1945-1951 

1950s-1990s 

Uranium Salvage: Salvage operations involved recovery of uranium 

from materials not considered production equipment, such as liquid 

and solid waste materials from maintenance/clean-up activities such as 

mop water, laundry washes, and floor drain residues. In an effort to 

recover uranium, combustible materials such as wood, rags, sponges, 

filter paper, and carbon solids were burned in muffle furnaces and 

incinerators. Other salvage operations included mechanical scraping 

and brushing, nitric-acid washing, and distillation. 

9206, 9207, 9211: 

• 9206 housed salvage 

operations and process 

operations similar to those in 

9207 and 9211. 

• 9207 and 9211 processed 

incinerated solid waste and 

recovered normal and lightly 

enriched uranium. 

1945-1951 
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Table 4-1: Key Uranium Operations 

(This table spans two pages) 

Key Uranium Operations Buildings Involved Dates of 

Operation 

Uranium Preparation/Recycle for Weapons Component Operations:

Y-12 began a continuous growth of uranium weapons component 

manufacturing operations and handled a variety of uranium compounds 

and enrichment. Enriched uranium prepared for reduction to metal 

involved conversion of uranium hexafluoride to uranium fluoride, 

purification of uranyl nitrate solutions, precipitation for uranium 

recovery, and then reduction to uranium metal. 

9212: 

• 9212 housed the largest 

chemical operations for 

enriched uranium 

purification, recovery, and 

chemical conversion as well 

as normal and depleted 

uranium machining 

operations. 

1952-1995 

Uranium Forming/Machining for Weapon Component Operations: 

Y-12 had operations capable of casting, rolling, and machining 

uranium metal. These operations handled enriched uranium, depleted 

uranium, and normal uranium. Uranium was pressed, rolled, shaped, 

and machined into finished weapon components. 

9206, 9207, 9211: 

• 9206 housed salvage 

operations and process 

operations similar to those in 

9207 and 9211. 

• 9207 and 9211 processed 

incinerated solid waste and 

recovered normal and lightly 

enriched uranium. 

1952-1995 

Uranium Component Assembly: Machined components were sent 

through finishing operations that included drilling, welding, brazing, 

polishing, and final specification checks. Assembly operations 

generally were not associated with significant releases of uranium 

compounds. Any measurable amounts of uranium were recovered and 

recycled back into the production stream. Uranium was routinely 

recovered from articles such as rags, paper towels, oils, and liquid 

waste products. Process exhaust stacks were equipped with highefficiency particulate air (HEPA) filters and periodically inspected for 

build-up of uranium. 

9202, 9204-2, 9204-2E:

• 9202 was primarily used for 

early pilot-scale operations 

that involved design and 

implementation of 

fabrication and assembly 

processes and final 

inspection procedures. 

• 9204-2, 9204-2E housed 

uranium assembly 

operations. 

1952-1995 

4.1.2 Y-12 Lithium Isotope Separation Process 

NOTE: Although not a radionuclide of concern for dose reconstruction, the Lithium Isotope 

Separation process provides additional detail regarding the activities conducted during the 

period under evaluation. 

Following the Soviet hydrogen bomb test in 1953 after which lithium was detected in the fallout, a 

"crash" program was implemented to develop a large-scale lithium separation plant. When the 

decision was made to pursue the development of the hydrogen bomb, Y-12 was chosen as the site for 

the separation of Li-6 from the more abundant Li-7. 
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The process concentrated Li-6 and combined the lithium with deuterium, a heavy isotope of hydrogen, 

to form lithium deuteride. Lithium deuteride is the major source of fuel for the hydrogen fusion 

which takes place in a hydrogen bomb explosion (Wilcox, 2001). 

Not unlike the earlier Manhattan Project, a massive mobilization of personnel and material resulted in 

operational plants in less than fifteen months. Lithium production cascades were housed in large 

buildings formerly used for uranium separation. Production for various separation processes started 

between 1953 and 1955. The chronology of lithium operations and facilities is shown in Table 4-2. 

Table 4-2: Chronology of Lithium Production Operations 

Time Period Operations 

1950, 1951 Operated Building 9733-2 – Development facility for Elex (Electrical Exchange) 

process 

1951, 1952 Operated Building 9733-1 – Development facility for Orex (Organic Exchange) 

process 

September 1951- 1955 Operated Building 9201-2 – Pilot plants for Elex and Colex (Column Exchange) 

processes 

April 1953 - May 1955 Operated Building 9201-2 – Pilot plant for Orex process 

1953 - Spring 1956 Operated Building 9204-4 – Elex Production Plant 

January 1955 – February 1959 Operated Building 9201-5 – Colex Production Plant 

Production activities stopped after 1959. In 1962, partial operations resumed through May 1963. 

Lithium production at Y-12 was terminated in 1963 as the stockpile grew and the material could be 

recycled from retired warheads (Wilcox, 2001). 

4.1.3 Y-12 Thorium Studies 

During the January 1, 1948 through December 31, 1957 period, quantities of thorium at Y-12 ranged 

from tens of kilograms in 1948, to hundreds of kilograms in 1952, to thousands of kilograms in 1955. 

Thorium work at Y-12 during this period was mainly of a research and development nature. 

Activities involving thorium are presented in chronological order below (Owings, 1995): 

1. Decontamination and decommissioning of the calutrons (primarily the 9201 buildings) occurred 

when the uranium enrichment operations using the alpha-track calutrons were terminated in 1946. 

This work involved cleaning out the uranium from the calutron vacuum chambers and the product 

"pockets." The uranium was removed by scraping and acid dissolution. A note in a Y-12 Health 

Physics Progress report indicates that thorium was used as a co-precipitation medium to increase 

the uranium recovery percentage from decontamination solutions. Although uranium enrichment 

with the calutrons stopped in 1947, it is not clear whether Y -12 continued to use thorium as a 

co-precipitating agent for later calutron operations (NIOSH, 2006a). 
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2. In 1952, the Isotopic Separation Program, which employed the beta calutrons in Building 9204-3, 

used small quantities of thorium for specific isotopic separation and purification (Air Monitoring, 

1943-1959). 

3. In 1956, thorium-oxide blending and slurry work associated with Research and Development 

activities were performed in Building 9204-1(Semiannual Report, 1956). 

4. Kilogram quantities of thorium were used in the Research and Development laboratories to 

develop and define the processes that would be incorporated in major thorium processing that took 

place after the time period under evaluation. A 1957 description of the Health Physics Program 

states: Thorium work is confined to one area in Building 9202, where the Development 

Department does some work with thorium (Health Physics Program, 1957, pdf p. 52). 

5. Kilogram quantities of thorium were used to support ORNL Research and Development activities 

in Buildings 9206 and 9212 (Owings, 1995). 

Based on the Y-12 thorium activity research performed for NIOSH’s evaluation of SEC-00028, 

another activity involved potential thorium exposure; however, the timeframe for this activity falls 

outside of the period under evaluation. Information on this activity is provided in support of the 1957 

end date for the class period. This thorium work began as a pilot program in 1958. Following the 

pilot program was a 17-year period (beginning in 1960) during which metric tons of thorium were 

processed (Assessment, 2001). This also corresponds to the period of available personnel monitoring 

and the incorporation of in vivo monitoring in the Y-12 Health Physics program. One hundred and 

three thorium fecal sample results were included in Delta View for the 1958 through 1960 time 

period; a small number of samples were also identified for the years of 1961 and 1962. Based on a 

review of the monitoring data, lung counting was the primary bioassay method used for thorium 

internal monitoring during the full-scale operational period. 

4.1.4 Y-12 Waste Disposal in the S-3 and New Hope Ponds 

Between 1951 and 1984, four seepage pits known as the S-3 Ponds were used to dispose of over 

2,700,000 gallons of a variety of liquid wastes, including concentrated acids, caustic solutions, mop 

waters, and by-products such as uranium and other heavy materials, from the uranium recovery 

processes. These unlined seepage pits were designed to allow liquid either to evaporate or percolate 

into the ground. Various metal impurities and radionuclides stripped from highly-enriched uranium 

during the solvent extraction steps in Buildings 9212 and 9206 (approximately 10% to 30% of 

recycled uranium, plutonium, neptunium, and technetium) were discharged with the dilute nitric acid 

and other process-derived acid wastewater into the S-3 Ponds prior to the mid-1980s (Recycled 

Uranium, 2000). 

New Hope Pond was constructed and placed in operation in the 1950s to provide a retention basin at 

the East end of Y-12. The pond facilitated mixing of water and offered a sampling point for rainwater 

runoff, once-through cooling water, steam plant boiler blow-down, and secondary production process 

wastewaters. The pond also served to remove any suspended contamination from rainwater, 

miscellaneous releases from various tank farms and storage yards, and inadvertent releases from 

process buildings (Recycled Uranium, 2000). 
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4.1.5 ORNL and Non-Uranium Activities at Y-12 

Space at Y-12 was used by the Oak Ridge National Laboratory (ORNL) Research and Development 

divisions for several projects. Four of the projects included the beta calutrons, the 86-inch cyclotron, 

the Criticality Experiments Facility, and the 5-MeV Van de Graff Accelerator, all of which are briefly 

summarized below. Several of these projects involved the production and/or separation and 

purification of both stable and radioactive isotopes. A listing of these isotopes is presented in 

Attachment 2. Generally, the radioactive isotopes were produced in small quantities and/or had short 

half-lives. 

Work performed at these facilities presented external and internal radiation exposure potential. At 

times, Y-12 workers supported efforts at the facilities and, in some cases, Y-12 employees were 

administratively transferred to ORNL. 

Beta Calutrons

During the 1950s, the Y-12 calutrons were used for the production, enrichment, and purification of an 

extensive list of stable and radioactive isotopes for worldwide medical research (see Attachment 2). 

A plutonium isotopic separation program using the calutrons was also in the planning and design 

stages during the period under evaluation (Wilcox, 1999). 

Based on a series of about 30 progress reports produced by the Electromagnetic Research Division 

and subsequent organizations, it is evident that plutonium isotopic enrichment work was occurring in 

1952 and 1957. Documents also show that plutonium urinalyses were performed from 1952 through 

at least 1965, air monitoring was performed, and personnel protection was addressed through clothing 

and respiratory protection. Calutron facilities provided for double containment of the calutron(s) and 

glove-box handling of collection pockets (Progress Report, 1962; Progress Report, 1958). 

86-Inch Cyclotron

The 86-inch cyclotron began operation in November 1950 and was used to perform radiation damage 

studies for the Nuclear Aircraft Project. As the world's largest fixed-frequency proton cyclotron, it 

produced a proton beam four times more intense than any other cyclotron. One of the original uses of 

the Oak Ridge 86-inch cyclotron was the production of polonium-208 (Polonium-208, 1952; Progress 

Report, 1963; ORNL, 1994). Polonium was produced in the 86-inch cyclotron as early as 1951. In 

1952, internal revisions of the position and mounting of the ion source resulted in proton energy of 23 

MeV. At the higher energy, the Po-208 yield was more than doubled and a total of approximately 9 

Ci of Po-208 were produced before the project was terminated in August 1953 (Polonium-208, 1952). 

During the next few years, the groundwork was laid for the production of neutron-deficient 

radioisotopes (Progress Report, 1963). However, from 1952 to 1961, the 86-inch cyclotron was used 

primarily for nuclear physics research by the ORNL Electronuclear Research Division 

(Electronuclear, 1954; Progress Report, 1958). Isotope production time was made available only 

when it did not interfere with the primary program (Progress Report, 1963). 
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Attachment 2 contains information regarding the stable and radioactive isotopes produced and/or 

separated and purified at Y-12. 

Critical Experiments Facility

Prior to the construction of the Critical Experiments Facility in 1950, several critical experiment 

programs had been carried out at ORNL and the K-25 Oak Ridge Gaseous Diffusion Plant (Safety 

Analysis, 1967). However, in 1949, due to the expected demands for further experimentation in: (1) 

the safety of metallurgical and chemical processes; and (2) the support of new reactor designs, the 

inadequacy of the previous facilities was recognized. This inadequacy was further emphasized by a 

program in Oak Ridge on the development of nuclear propulsion for aircraft (ORNL, 1994). As a 

result, it was decided that a laboratory adequate for a wide variety of critical experimentation be 

established, and that the various programs of critical experiments in Oak Ridge be combined and the 

work administered by ORNL (Safety Analysis, 1967). Thus, near-critical and criticality experiments 

were started at the Critical Experiments Facility in late August and early September 1950. 

The Critical Experiments Facility was at a remote site in the Southwest portion of the Y-12 complex 

in a pocket formed by surrounding hills as much as 200 feet higher than the Critical Experiments 

Facility building itself (Safety Review, 1962; Safety Analysis, 1967). During its operational years, 

access to the Critical Experiments Facility was restricted by means of a chain link fence (Safety 

Review, 1962; Safety Analysis, 1967). 

5-MeV Van de Graff Accelerator

In the early 1950s, a 5-MeV Van de Graff accelerator operated for about one year in the east end of 

Building 9202-2 while a permanent structure was being built for the accelerator at the X-10 site. The 

5-Me V Van de Graff Accelerator was an X-10 project and the health physicists and all other workers 

involved with the Van de Graff were X-10 employees (Oak Ridge, 1993; Struxness, January-June 

1951; Struxness, July-December 1951). 

4.1.6 Weapons Assembly and Disassembly 

Information regarding weapons assembly and disassembly work at Y-12 was obtained through 

document reviews and a series of interviews with employees with first-hand knowledge of Y-12 

weapons activities during the period under evaluation. The interviews were conducted as part of the 

evaluation effort for petition SEC-00028 (NIOSH, 2006a; NIOSH, 2006b). No additional interviews 

were necessary for this current evaluation because SEC-00186 specifies the same class period as SEC00028. 

From the document reviews and interviews, it was learned that weapons assembly/disassembly work 

began as early as 1952-1953. Typically, weapons components were assembled at Y-12 and then sent 

to another site(s) for further assembly. Much more assembly work was done than disassembly work. 

Prior to 1960, work was done in glove boxes or in open areas which were, by necessity, very clean 

environments. The exposure potential was from external radiation only since the parts for assembly 

were essentially clad or otherwise sealed. Badges were worn on normal plant clothing. 
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During the weapons assembly and disassembly operations, a small crew (a maximum of three plus 

one foreman) was used. These crews never included maintenance or crafts people. The interviewed 

workers agreed that the presence of pipefitters, plumbers, and steamfitters in the assembly areas was 

infrequent and only after the assemblies were either covered and/or removed, thus making radiation 

exposure potential essentially nonexistent. In addition, when maintenance personnel were needed in 

the area, they were always required to wear personal dosimeters. 

4.2 Radiation Exposure Potential from Operations 

The following subsections provide an overview of the internal and external exposure potential for the 

Y-12 Plant class under evaluation. 

Over the 1948 through 1957 time period, many individual research and development projects occurred 

at Y-12 involving various radiological exposure sources. The use of thorium at Y-12 is associated 

with two test batches processed through Building 9204-3 calutrons (for enrichment), Research and 

Development activities in Buildings 9202, 9204-1, 9206, and 9212, and use as a co-precipitation 

medium. In addition, there exist a number of radionuclides produced as a result of 86-inch cyclotron 

operations. However, the principal source term at the plant was (and continues to be) uranium process 

materials. The uranium materials existed in any of the standard ICRP-68 clearance classes or in any 

combination thereof. 

In addition, because Y-12 served primarily as a nuclear weapons fabrication and production facility 

during this period, the uranium that was present included natural uranium, depleted uranium, and 

enriched uranium. 

4.2.1 Alpha Particle Emissions 

Both U-235 and U-238 are primarily alpha-particle emitters. As such, gamma radiation exposure 

potential was very low for most members of the class under evaluation. The majority of the 

radiological exposure potential at Y-12 has been internal and chronic in nature, resulting from 

inhalation or ingestion of particles comprised of various forms of uranium during nuclear material 

fabrication and processing work. Uranium-bearing chemicals present at the facility during the 1948 

through 1957 time period included, but are not limited to (Oak Ridge, 1993, pdf p. 222; Oak Ridge, 

1999, pdf pp 172-185; Technical Basis, 2003, pdf p. 11): 

• Uranium oxide (D3O8) 

• Uranium dioxide (UO2) 

• Uranium trioxide (UO3) 

• Uranium hexafluoride (UF6) 

• Ammonium diuranate [(NH4)2U2O7] 

• Uranyl nitrate [UO2(NO3)2] 

• Uranium peroxide (UO4 ·2H2O) 

• Uranium tetrachloride (UCl4) 

• Uranium pentachloride (UCl5) 

• Uranium tetrafluoride (UF4) 
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As previously discussed, Research and Development activities involving thorium (including Th-230 

and Th-232 in limited quantities) were also performed during the evaluation period. Th-232 decays 

primarily by alpha emission, yielding a 4.081 MeV alpha particle in the process. Although Th-232 

has a long (1.405 x 1010 years) half-life, many of its short-lived decay products, such as Ra-224 and 

Rn-220, also decay by alpha emissions. Similarly, Th-230 also decays primarily by alpha emission, 

yielding a 4.770 MeV alpha particle with a half-life of 7.538 x 104

 years. Like Th-232, Th-230 also 

gives rise to several daughter radionuclides that decay by alpha emission with short half-lives, as 

shown in Table 4-3. However, concerns associated with thorium alpha emissions/exposures were 

limited by operational location and design to Buildings 9202, 9204-1, and 9204-3. 

Table 4-3: Thorium Decay Chain Alpha Emissions 

Isotope Half-life Energy Released (MeV) 

Th-230 7.5380 x 104 y 4.770 

Ra-226 1.602 x 103 y 4.871 

Rn-222 3.8235 d 5.590 

Po-218 3.10 min 6.115 

At-218 1.5 s 6.874 

Rn-218 35 ms 7.263 

Bi-214 19.9 min 1.024 

Bi-210 5.013 d 5.982 

Po-210 138.376 d 5.407 

Th-232 1.405 x 1010 y 4.081 

Th-228 1.9116 y 5.520 

Ra-224 3.6319 d 5.789 

Rn-220 55.6 s 6.404 

Po-216 0.145 s 6.906 

Bi-212 60.55 min 6.208 

Po-212 299 ns 8.955 

4.2.2 Beta/Photon Radiation Fields 

Though less of a threat than internal exposure, significant external exposure potential existed at times 

in specific locations/activities. The external workplace radiation fields of most concern were due to 

processes involving either enriched uranium or depleted uranium. Additional radiation fields of 

concern (summarized in Table 4-3) involved industrial radiation-generating equipment (X-rays and 

electron accelerators) and isotopic gamma-ray and neutron sources for testing purposes (e.g., Co-60, 

Cf-252, and radium-beryllium or polonium-beryllium neutron sources). 

As noted in Section 4.2.1, the U-235 and U-238 contained in Y-12 materials are primarily alphaemitters. However, U-235 does emit a 185-Ke V photon in 54% of its decays and short-lived U-238 

decay products (Th-234, Pa-234m, and Pa-234) are beta and photon emitters. From an external dose 

standpoint, the most significant radiations emitted by these U-238 decay products are: (1) the 2.29-

MeV beta particle from Pa-234m; and (2) the photons emitted by Pa-234 with energies as large as 

1.962 MeV. In addition, the various nuclides produced as a result of cyclotron operations (listed in 

Appendix 2) would produce an external exposure potential that is proportional to the emitted energy 

of the nuclide as well as the quantity produced. 
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Table 4-4 summarizes beta and photon energies as associated with various Y-12 processes (ORAUTTKBS-0014-6). 

Table 4-4: Beta and Photon Energies 

Y-12 Site Processes Building Operations Radiation 

type 

Energy 

Selectiona Percentb 

Begin End 

Enriched uranium product recovery 

and salvage operations 

9203 1947 1951 Beta 

Photon 

> 15 keV 

30-250 keV 

100% 

9206 100% a 1947 1959 

9211 1947 1959 

9201-1 1952 1963 

Uranium chemical operations and 

weapon production operations 

9202 1947 1995 Beta 

Photon 

> 15 keV 

30-250 keV 

100% 

9206 100% c 1947 1995 

9212d 1949 Ongoing 

Special nuclear material receiving 

and storage 

9720-5 1949 Ongoing Photon 30-250 keV 100% 

Uranium forming and machining for 

weapon component operations 

9201-5 1949 Ongoing Beta 

Photon 

> 15 keV 

30-250 keV 

100% 

9204-4 1949 Ongoing 100% 

9215 1950 Ongoing

Depleted uranium process operations 

9201-5 1949 Ongoing Beta 

Photon 

> 15 keV 

30-250 keV 

> 250 keV 

100% 

50% 

50% 

9204-4 1949 Ongoing

9766 1949 Ongoing

9998 1949 Ongoing

Final weapon component assembly 

operations 

9204-2 1952 Ongoing Beta 

Photon 

> 15 keV 

30-250 keV 

100% 

9204-2E 1952 Ongoing 100% 

ORNL 86-inch cyclotron 9201-2 1950 Ongoing Photon 30-250 keV 

> 250 keV 

50% 

50% 

Chemical assay and mass 

spectrometry laboratories 

9203 1947 Ongoing Photon Specific to 

radiation 

source. 

Photon default 

values: 

30-250 keV 

>250 keV 

50% 

50% 

Radiographic laboratory 9201-1 1947 Ongoing Photon 

Calibration laboratory 9983 1949 Ongoing Photon 

Weapon component assay laboratory 

9995 1952 Ongoing Photon 

Notes: 

a

 Source: NIOSH Interactive RadioEpidemiological Program (NIOSH-IREP) Technical Documentation (NIOSH-IREP, 

 2002) 

b

 Source: Handbook of Health Physics and Radiological Health (Rad Handbook, 1998) c Building 926 Complex includes Buildings 9768, 9720-17, 9409-17, 9510-2, 9767-2, and the east and west tank farm pits. 

d Building 9212 Complex includes Buildings 9809, 9212, 9818, 9815, and 9980. 
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4.2.3 Neutron Sources 

Radionuclide sources that produced neutrons by alpha particle reactions in boron or beryllium 

provided a convenient source of neutrons for a number of applications (Rees, 1967). Their use at 

Y-12 is summarized in Table 4-5. 

Table 4-5: Neutron Sources used at the Y-12 Plant 

Location Y-12 Building Neutron Source 

Assay Laboratorya 

Critical Experiments Facilityb 

9203 (Room 8), 9205 

9213 

Radium-Beryllium, Polonium-Beryllium 

Polonium-Beryllium, Polonium Beryllium 

Fission Neutrons 

Electromagnetic Researchc 9201-2, 9204-3 Polonium-Beryllium 

86-Inch Cyclotron 

Health Physicsd

Instrument Departmente 

Chemical Operationsf 

9983 (Calibration Laboratory) 

9737 

9202, 9206, 9212 

Polonium-Beryllium, Americium-Beryllium 

Polonium Beryllium 

Highly Enriched Uranium Fluoride and Oxide 

Compounds 

Sources: 

a Struxness, 1949; Struxness, November-December 1950 b Struxness, November-December 1950; Struxness, January-June 1953; Safety Review, 1962; Safety Analysis, 1967 c Struxness, January-June 1951; Struxness, November-December 1950; ORNL 1173; ORNL 1196; ORNL 1392; 

Struxness, July-December 1951; Struxness, January-July 1952; Livingston, 1958 d Struxness, January-June 1951; Struxness, January-July 1952; Y-12 Plant, 1963 e Struxness, January-June 1951 f ORAUT-TKBS-0014-2; DOE, 2000 

Neutron sources were used in the basic research (Buildings 9201-2 and 9204-3), critical assembly and 

reactor research (Building 9213), calibration of radiation dosimeters and radiation detection 

instruments (Buildings 9737 and 9983), and material assay (Buildings 9203 and 9205). Shielding was 

used to protect workers from unnecessary exposures to the radionuclide sources. Nevertheless, some 

dose was received even in shielded areas and some dose was also received from the bare sources. The 

largest exposure would occur while sources were withdrawn from their shields during the calibration 

of radiation instruments or during periodic tests for leakage of radioactive materials from the sealed 

containers housing the sources. 

Although the neutron spectrum produced as a result of the α,n reaction can be complex, Table 4-6 lists 

the average neutron energies and the neutron yield per curie of the alpha-emitting isotope. 

Table 4-6: Neutron Data for Commonly-used Neutron Sources 

Source Average Neutron Energy 

(MeV) 

Yield per Ci 

(neutrons per s) 

Polonium-Beryllium 4.2 2.5 x 106

Radium-Beryllium 4.0 1.3 x 107

Americium-Beryllium 4.5 2.2 x 106

Source: Rad Handbook, 1998 
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Two other neutron sources not listed in Table 4-4 are a Cockcroft-Walton linear accelerator capable of 

producing a maximum of 1E10 fast neutrons per second (Struxness, January-June 1953) and a 5-MeV 

Van de Graff accelerator capable of producing a fast neutron flux as high as 560 fast neutrons per 

square-centimeter-second near the target (Struxness, January-June 1951; Struxness, July-December 

1951). The Cockcroft-Walton was installed in late 1951 in the ORNL Biology Division building 

housing the Oak Ridge 86-inch cyclotron (Building 9201-2). The 5-MeV Van de Graff was operated 

at Y-12 during part of 1951 and part of 1952 while a permanent structure was being built for the 

accelerator at the ORNL Site (ORNL, 1994). 

The X-ray or electron-generating equipment used at Y-12 included linear electron beams, electron 

beam welders, scanning electron microscopes, X-ray photoelectron spectrometers, secondary ion mass 

spectrometers, enclosed beam diffraction equipment, and medical diagnostic X-ray equipment. The 

emitted energy range is from 15 keV to 9 MeV (Technical Basis, 2001). 

4.2.5 Recycled Uranium and Other Radionuclides of Concern 

From 1953 until 1999, recycled uranium activities introduced radionuclides into Y-12 plant systems 

unlike those typically associated with the Y-12 weapons processes. These contaminants were a result 

of fission and activation processes of a variety of uranium enrichment isotope mixtures that were 

irradiated in production and test reactors. As a result, the recycled uranium contained transuranic 

material, fission products, and reactor-generated uranium products. After completing its useful life in 

the reactors, the unused uranium in the spent fuel elements or targets was recovered in chemical 

extraction plants and returned to the inventories in the DOE system along with trace quantities of the 

contaminants. 

The primary recycled uranium contaminants of concern at Y-12 arrived in 1953 with shipments of 

very-highly-enriched uranium from the Idaho Chemical Processing Plant. A few years later, the 

Savannah River Plant started sending large quantities of highly-enriched uranium/very-highlyenriched uranium and recycled uranium materials. The primary contaminants were Pu-238 (Pu-239 in 

lesser quantities), Np-237, and Tc-99. All of the highly-enriched uranium/very-highly-enriched 

uranium was processed through chemical extraction, which had been designed to remove other 

contaminants such as trace metals. However, some removal of recycled uranium radioisotopic 

contaminants occurred (in parts per billion quantities) and these were generally disposed of with the 

raffinates (Technical Basis, 2001). 

Shortly after recycled uranium was introduced at Y-12, the AEC directed that an effort be made to 

remove Np-237 from process streams for use as targets in the production of Pu-238 in the production 

reactors. X-10 designed the ion exchange system for liquid processes, which contained Np-237, and 

Y-12 installed this system on the liquid feed to the chemical processing plant. The spent columns 

were removed and sent off site for further processing. No significant handling of these sources of 

neptunium occurred at Y-12 (NIOSH, 2006a). 
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4.3 Time Period Associated with Radiological Operations 

Per the DOE Office of Health, Safety and Security, the time period associated with DOE operations at 

the Y-12 Plant is from 1942 to the present. As presented in Section 3.0, HHS has already designated 

(for SEC-00028) that monitored workers who worked in Buildings 9201-3, 9202, 9204-1, 9204-3, 

9206, or 9212, or with cyclotron operations in Building 9201-2, during the period from January 1948 

through December 1957 be included in the SEC. The period of radiological operations associated 

with this current evaluation remains the same as that associated with the previously-designated class 

for SEC-00028. However, the time period for this evaluation report on Y-12 exposures specifies the 

logical start date of January 1, 1948 and the logical end date of December 31, 1957. 

4.4 Site Locations Associated with Radiological Operations 

The Y-12 facility is comprised of many buildings where many different (often experimental) activities 

occurred. As presented in Section 3.0, HHS has already designated (for SEC-00028) that monitored 

workers working in Buildings 9201-3, 9202, 9204-1, 9204-3, 9206, or 9212, or with cyclotron 

operations in Building 9201-2, during the period from January 1948 through December 1957 be 

included in the SEC. Through the course of ongoing dose reconstruction and research associated with 

the SEC-00028 class period, NIOSH has determined that, due to undocumented worker movements 

across the site, limited claimant-specific information pertaining to work locations, and a determination 

by the Department of Labor that employment records do not indicate work locations, NIOSH is 

unable to eliminate any specific worker from potential exposure scenarios based on assigned work 

location. 

4.5 Job Descriptions Affected by Radiological Operations 

Y-12 workers were potentially exposed to radiation in areas where radiological operations took place. 

NIOSH has determined that the site-specific and claimant-specific data available for the Y-12 Plant 

for the time period under evaluation are insufficient to allow NIOSH to determine that any specific 

work group was not potentially exposed to thorium or cyclotron-related radionuclides during the 

period under evaluation. 

NIOSH has insufficient information associating job titles and/or job assignments with specific 

thorium or cyclotron radiological operations or conditions. Without such information, NIOSH is 

unable to define potential radiation exposure conditions based on worker job descriptions. 

5.0 Summary of Available Monitoring Data for the Proposed Class 

The primary data used for determining internal exposures are derived from personal monitoring data, 

such as urinalyses, fecal samples, and whole-body counting results. If these are unavailable, the air 

monitoring data from breathing zone and general area monitoring are used to estimate the potential 

internal exposure. If personal monitoring and breathing zone area monitoring are unavailable, internal 

exposures can sometimes be estimated using more general area monitoring, process information, and 

information characterizing and quantifying the source term. 
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This same hierarchy is used for determining the external exposures to the cancer site. Personal 

monitoring data from film badges or thermoluminescent dosimeters (TLDs) are the primary data used 

to determine such external exposures. If there are no personal monitoring data, exposure rate surveys, 

process knowledge, and source term modeling can sometimes be used to reconstruct the potential 

exposure. 

A more detailed discussion of the information required for dose reconstruction can be found in 

OCAS-IG-001, External Dose Reconstruction Implementation Guideline, and OCAS-IG-002, Internal 

Dose Reconstruction Implementation Guideline. These documents are available at: 

http://www.cdc.gov/niosh/ocas/ocasdose.html. 

5.1 Data Capture Efforts and Sources Reviewed 

As a standard practice, NIOSH completed an extensive database and Internet search for information 

regarding Y-12 Plant. The database search included the DOE Legacy Management Considered Sites 

database, the DOE Office of Scientific and Technical Information (OSTI) database, the Energy 

Citations database, the Atomic Energy Technical Report database, and the Hanford Declassified 

Document Retrieval System. In addition to general Internet searches, the NIOSH Internet search 

included OSTI OpenNet Advanced searches, OSTI Information Bridge Fielded searches, Nuclear 

Regulatory Commission (NRC) Agency-wide Documents Access and Management (ADAMS) web 

searches, the DOE Office of Human Radiation Experiments website, and the DOE-National Nuclear 

Security Administration-Nevada Site Office-search. Attachment One contains an updated summary of 

Y-12 Plant documents. The summary specifically identifies data capture details and general 

descriptions of the documents retrieved. 

In addition to the database and Internet searches listed above, NIOSH identified and reviewed 

numerous data sources to determine information relevant to determining the feasibility of dose 

reconstruction for the class of employees under evaluation. This included determining the availability 

of information on personal monitoring, area monitoring, industrial processes, and radiation source 

materials. The following subsections summarize the data sources identified and reviewed by NIOSH. 

Detailed information regarding NIOSH’s data capture efforts for the Y-12 Plant can be found in the 

related NIOSH evaluation reports for SEC-00018, SEC-00028, and SEC-00098 (NIOSH, 2005; 

NIOSH, 2006a; NIOSH, 2006b; NIOSH, 2008). 

5.2 Worker Interviews 

To obtain additional information in support of its 2006 evaluation of Petition SEC-00028, NIOSH 

interviewed nine former Y-12 Plant employees. Details regarding these interviews can be found in the 

SEC Petition Evaluation Report for Petition SEC-00028, Y-12 Plant (NIOSH, 2006a). Additional 

interviews for the specific purpose of supporting these evaluations were not deemed necessary, and 

therefore were not performed. 
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5.3 Internal Personnel Monitoring Data 

The earliest urine sample results available are from 1950 when samples were collected monthly. 

Weekly collection began in 1951. As was the case for external monitoring, collection of routine urine 

samples was based on exposure potential. However, available Y-12 records show that the number of 

employees receiving internal monitoring was generally greater than the number of employees who 

received external monitoring (see the Y-12 internal and external data summary in Section 5.4). 

Fluorometric analyses were performed on samples submitted from workers in natural and depleted 

uranium work areas and electro-deposition of uranium followed by gross alpha counting for samples 

submitted by workers in enriched uranium areas. (NIOSH, 2006a, NIOSH, 2006b) 

Table 5-1 provides a summary of the uranium urinalysis records available through the ORAU Center 

for Epidemiologic Research. 

Table 5-1: Summary of Available Y-12 Uranium Urinalysis Data (1948-1960) 

Year Total Number of 

Employees 

Urinalysis (Uranium) 

No. of Records No. of Employees Monitored 

1948 2,511 - - 

1949 2,248 - - 

1950 2,552 1,110 166 

1951 4,036 4,124 367 

1952 4,169 13,317 393 

1953 4,866 14,222 490 

1954 5,817 23,430 1,316 

1955 5,768 28,806 1,225 

1956 5,443 29,914 1,119 

1957 5,169 33,443 1,443 

1958 5,164 38,783 1,791 

1959 5,460 47,339 2,277 

1960 5,593 46,381 2,193 

Notes: 

A table cell with a hyphen (-) indicates No Data Available. 

a

 External monitoring records include all currently known available gamma, beta, and neutron data. 

In addition to the uranium urinalyses, non-uranium/special urinalyses were performed. These data are 

maintained in a separate Y-12 database known as Delta View (see Section 4.8). Delta View is 

comprised of approximately 470,000 scanned images of hard copy reports and monitoring data 

printouts associated primarily with Y -12 personnel. Information on these images is varied and can 

include general information in addition to bioassay data. Examples include selected dose calculation 

reports, data from both Y-12 and X-l0 analytical labs, and lab reports of bioassay urine and fecal 

analysis results. (NIOSH, 2006a; NIOSH, 2006b) 
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Table 5-2 provides a summary compilation of non-uranium bioassay results extracted from 

approximately 6,000 images stored in the Delta View Database. These 6,000 images were extracted 

from the system using pre-defined keywords located in comments fields that were thought to represent 

Y -12 bioassay data on non-uranium isotopes for the period under evaluation. 

Table 5-2: Non-Uranium Bioassay Results from Delta View 

Isotope 1952 1953 1954 1955 1956 1957 1958 1959 1960 

Alpha emitters in urine 2 0 0 0 0 0 0 0 0 

Tritium 0 0 0 0 605 0 0 0 0 

Polonium 0 18 0 0 0 0 0 0 0 

Plutonium 275 100 277 52 36 0 45 30 71 

Thorium 0 0 0 0 0 0 44 37 12 

Table 5-2 lists the quantities of available fecal analysis data, starting in 1958, for the thorium-related 

activities associated with Research and Development performed in Buildings 9202, 9204-1, and 9204-

3. A total of 93 thorium fecal sample results were identified in the Delta View database for the 1958 

through 1962 time period. Additional details regarding the various analyses used and the associated 

minimum detectable activities are presented in the Y-12 Occupational Internal Dose Technical Basis 

Document, ORAUT-TKBS-0014-5. 

Whole-body counting was not routinely practiced at Y-12. The primary in vivo detection method was 

chest counting. The Y-12 in vivo chest-counting facility was developed in the late 1950s but was not 

put into routine use until 1961. Chest counting was done for uranium and thorium isotopes, 

neptunium, and other radionuclides. 

No in vitro or in vivo bioassay data specific to thorium or cyclotron-produced radionuclide monitoring 

during the period under evaluation were identified in any of the documentation reviewed by NIOSH 

for this report or for the previous NIOSH evaluation of SEC-00028. 
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5.4 External Personnel Monitoring Data 

Prior to 1950, external monitoring was performed on a small scale to monitor the external exposures 

of individuals working in the Assay Laboratories, Radiographic Shop, Spectrographic Shop, and 

Machine Shops where uranium metals were being handled (Murray, January 1948; Murray, February 

1948; Struxness, May 1948; Struxness, December 1948). External monitoring was accomplished by 

wearing pocket ionization chambers (PICs), also called pocket meters or pocket chambers, that were 

typically changed weekly. A limited set of external monitoring data exists for 1948 and 1949 (West, 

1980). NIOSH has also obtained an electronic file with 11,492 records covering the period under 

evaluation. Data elements in the electronic file include film badge ID, date of weekly readings, PIC 

readings, three photographic film dosimeter readings, and descriptive comments. NIOSH is 

attempting to link the film badge ID in the Y-12 pre-1950 external monitoring file with Y-12 worker 

names in the ORAU DOE facility database, but has not yet verified the accuracy of this linkage. The 

data are, however, currently useful in a variety of ways for dose reconstruction. Details regarding this 

monitoring period and associated data set have been documented in External Radiation Monitoring at 

the Y-12 Facility During the 1948-1949 Period (ORAUT-OTIB-0047). 

An expanded personnel monitoring program for external radiation exposure was initiated at Y-I2 in 

1950 (McLendon, 1960). All Y-12 personnel working with: (1) depleted uranium; (2) discrete 

gamma, beta, or neutron sources; (3) X-rays; and (4) materials contaminated with fission products 

were required to wear a film badge dosimeter. The film badges were augmented with film rings to 

assess the radiation exposure to uranium metal workers’ hands. Dosimetry practice was to record 

weekly dose to skin from beta particles (and low-energy X-rays) or the penetrating doses from gamma 

rays as zero if they were less than 30 mrem (West, 1993). Film badges containing a nuclear track 

emulsions type-A film (so-called NTA film) were used to monitor neutron exposures. These 

NTA-equipped badges were assigned only to those workers who had a substantial potential for 

neutron exposure, and were exchanged on a biweekly schedule. The minimum detection limit (MDL) 

of the neutron film is uncertain, but it is believed to be about 50 mrem for all years of use at Y-12 

(ORAUT-TKBS-0014-6). 

Dosimetry policy from 1952 through mid-1956 was to assign the MDL dose for weeks with 

monitoring results less than the MDL for either beta or gamma radiation. The MDL was 50 mrem for 

1952 (weeks 1-38 approximately), all of 1953, and 1954 (weeks 1-30, approximately). In 1952, the 

MDL was 43 mrem for weeks 39-52. For the remainder of 1954 and all of 1955 and 1956, the MDL 

was 30 mrem. In practice, however, weekly doses less than the MDL were often left blank (NIOSH, 

2006a). 

The Oak Ridge Associated Universities Center for Epidemiologic Research received a copy of the 

Y-12 monitoring records. These files contained records for more than 17,000 Y-12 workers. From 

these Y-12 records, available external data relevant to the subject class are presented by year in Table 

5-3. 
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Table 5-3: Summary of Available Monitoring Data for Y-12 Workers (1948-1960) 

Year Total No. of 

Employees No. of Records No. of Employees Monitored

1948 2,511 3,599 162 

1949 2,248 7,893 49 

1950 2,552 268 148 

1951 4,036 406 184 

1952 4,169 1,157 498 

1953 4,866 793 387 

1954 5,817 1,240 682 

1955 5,768 1,920 624 

1956 5,443 2,181 730 

1957 5,169 2,510 796 

1958 5,164 2,879 996 

1959 5,460 3,644 1,266 

1960 5,593 4,296 1,336 

Notes: 

Source: NIOSH, 2006a 

A table cell with a hyphen (-) indicates No Data Available. 

a

 External monitoring records include all currently known available gamma, beta, and neutron data. 

5.5 Workplace Monitoring Data 

In addition to personal monitoring for internal and external doses, thousands of air samples were 

collected during the January 1, 1948 through December 31, 1957 time period. Most air samples were 

obtained from general air samplers placed in areas where some possibility of airborne contamination 

existed. Breathing zone samples were also collected. Samples were predominantly analyzed for 

uranium and, to a lesser extent, thorium. The data for uranium air sampling are summarized in Table 

5-4. The results were generally reported as disintegrations per minute (dpm)/m3 uranium in air. 

Thorium air sampling for the 1948 through 1957 timeframe was limited. To date, NIOSH has 

obtained a limited number of these thorium air sampling results. As presented in NIOSH’s previous 

evaluation of SEC-00028 (NIOSH, 2006a; NIOSH 2006b), no thorium production level work 

occurred in the period under evaluation in this report. Full production did not get underway until 

1960 with the highest thorium production activity occurring between 1962 through 1965 and 1970 

through 1975. Over 80,000 thorium air sampling records are available covering the production years 

extending from 1960 through 1976 (NIOSH, 2006a). 
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Table 5-4: Summary of Available Uranium Air Monitoring Data for Y-12 Workers (1948-1960) 

Year Total No. of Employees No. of Uranium Records 

1948 2,511 - 

1949 2,248 - 

1950 2,552 - 

1951 4,036 15,655 

1952 4,169 - 

1953 4,866 8,010 

1954 5,817 20,217 

1955 5,768 26,976 

1956 5,443 36,280 

1957 5,169 41,354 

1958 5,164 77,373 

1959 5,460 66,150 

1960 5,593 44,433 

Notes: 

A table cell with a hyphen (-) indicates No Data Available. 

a

 External monitoring records include all currently known available gamma, beta, and neutron data. 

5.6 Radiological Source Term Data 

During the period from January 1, 1948 through December 31, 1957, workers may have been exposed 

to uranium, thorium, and their decay progeny. During the operation of the cyclotron, workers may 

have been exposed to various radionuclides arising from cyclotron operations. Table A2-1 in 

Appendix 2 lists the quantities of the various radionuclides produced and/or processed at Y-12. 

Additional information regarding the Y-12 Plant source term data available to NIOSH can be found in 

the related Y-12 Plant Evaluation Report for SEC-00028 (NIOSH, 2006a; NIOSH, 2006b). 

6.0 Feasibility of Dose Reconstruction for the Proposed Class 

42 C.F.R. § 83.14(b) states that HHS will consider a NIOSH determination that there was insufficient 

information to complete a dose reconstruction, as indicated in this present case, to be sufficient,

without further consideration, to conclude that it is not feasible to estimate the levels of radiation 

doses of individual members of the class with sufficient accuracy. 

In the case of a petition submitted to NIOSH under 42 C.F.R. § 83.9(b), NIOSH has already 

determined that a dose reconstruction cannot be completed for an employee at the DOE or AWE 

facility. This determination by NIOSH provides the basis for the petition by the affected claimant. 

Per § 83.14(a), the NIOSH-proposed class defines those employees who, based on completed 

research, are similarly affected and for whom, as a class, dose reconstruction is similarly not feasible. 
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In accordance with § 83.14(a), NIOSH may establish a second class of coworkers at the facility for 

whom NIOSH believes that dose reconstruction is similarly infeasible, but for whom additional 

research and analysis is required. If so identified, NIOSH would address this second class in a 

separate SEC evaluation rather than delay consideration of the claim currently under evaluation (see 

Section 10). This would allow NIOSH, the Board, and HHS to complete, without delay, their 

consideration of the class that includes a claimant for whom NIOSH has already determined a dose 

reconstruction cannot be completed, and whose only possible remedy under EEOICPA is the addition 

of a class of employees to the SEC. 

This section of the report summarizes research findings by which NIOSH determined that it lacked 

sufficient information to complete the relevant dose reconstruction and on which basis it has defined 

the class of employees for which dose reconstruction is not feasible. NIOSH’s determination relies on 

the same statutory and regulatory criteria that govern consideration of all SEC petitions. 

6.1 Feasibility of Estimating Internal Exposures 

NIOSH has evaluated the available personnel and workplace monitoring data and source term 

information and has determined that there are insufficient data for estimating internal exposures, as 

described below. 

As presented in Section 3.0 of this report, HHS has designated an SEC class for Y-12 workers for the 

period from January 1948 through December 1957 (HHS, 2006). In the class designation letter, 

HHS states: 

There are insufficient bioassay or air sampling data to reconstruct internal thorium dose for 

employees who worked from January 1948 through December 1957 in buildings where thorium 

operations took place: buildings 9201-3, 9202, 9204-1, 9204-3, 9206, and 9212. 

There are insufficient bioassay or air sampling data to reconstruct internal dose for cyclotron 

workers (employees who worked in Building 9201-2) from January 1948 through December 1957. 

These workers may have accumulated substantial chronic exposures through episodic intakes of a 

variety of radionuclides that were produced during the cyclotron operation period. 

The associated SEC class designated by HHS included only those employees who worked “in 

Building 9201-3, 9202, 9204-1, 9204-3, 9206, or 9212” or “in Building 9201-2” (HHS, 2006). This 

class description was based on the NIOSH determination that exposure potential was limited to 

workers in these buildings, that all workers with the potential for radiation exposures during the 

proposed SEC class time period were included in the external dose monitoring program, and that 

unmonitored workers had no potential for radiation exposures. 

A recent review of existing SEC class definitions evaluated criteria such as consistency, applicability 

and whether any class definitions needed to be corrected by NIOSH (NIOSH 2010). In this review 

NIOSH determined that the class definition as defined in SEC-00028 needed revising, because 

problems existed with the implementation of the previous class. In addition, through the course of 

ongoing dose reconstruction and research, NIOSH has determined that, due to undocumented worker 

movements across the site, limited claimant-specific information pertaining to work locations, and a 

determination by the Department of Labor (DOL) that employment records do not indicate work 
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locations, NIOSH is unable to eliminate any specific worker from potential exposure scenarios based 

on assigned work location. NIOSH has found that a determination cannot always be made as to the 

specific area an employee worked in, or whether an employee should have been monitored for 

radiological exposures. Accordingly, NIOSH has determined that it is necessary to remove the areaspecific and monitoring criteria from the class description associated with SEC-00028 thorium and 

cyclotron exposures for the period from January 1, 1948 through December 31, 1957. As such, 

NIOSH has determined that it is also necessary to expand the SEC class definition to include all areas 

of the Y-12 Plant, and all employees of DOE, its predecessor agencies, and their contractors and 

subcontractors who worked at the Y-12 Plant during the period from January 1, 1948 through 

December 31, 1957. The SEC-00186 evaluation recommends a class that is consistent with current 

DCAS methods for defining a recommended SEC class. 

A method for estimating uranium exposures for the years between 1948 and 1957 in Buildings 9202, 

9204-1, 9204-3, 9206, and 9212 was included in the Evaluation Report for SEC-00028. This could be 

applied for workers who could be shown to have worked within those buildings. Dose reconstructions 

for individuals employed at Y-12 during the evaluated time period, but who do not qualify for 

inclusion in the SEC, may be performed using these data as appropriate. 

NIOSH does not have access to sufficient personnel monitoring, workplace monitoring, or source 

term data to estimate potential internal exposures to thorium or radionuclides produced as a result of 

cyclotron operations during the period from January 1, 1948 through December 31, 1957. 

Consequently, NIOSH finds that it is not feasible to estimate, with sufficient accuracy, internal 

exposures to thorium or radionuclides produced as a result of cyclotron operations and resulting doses 

for the class of employees covered by this evaluation. 

Although NIOSH found that it is not possible to completely reconstruct internal radiation doses for the 

period from January 1, 1948 through December 31, 1957, NIOSH intends to use any internal 

monitoring data that may become available for an individual claim (and that can be interpreted using 

existing NIOSH dose reconstruction processes or procedures). Dose reconstructions for individuals 

employed at the Y-12 Plant during the period from January 1, 1948 through December 31, 1957, but 

who do not qualify for inclusion in the SEC, may be performed using these data as appropriate. 

6.2 Feasibility of Estimating External Exposures 

This evaluation responds to a petition based on NIOSH determining that internal radiation exposures 

to thorium could not be reconstructed for a dose reconstruction referred to NIOSH by the Department 

of Labor (DOL). As noted above, HHS will consider this determination to be sufficient without 

further consideration to determine that it is not feasible to estimate the levels of radiation doses of 

individual members of the class with sufficient accuracy. Consequently, it is not necessary for 

NIOSH to fully evaluate the feasibility of reconstructing external radiation exposures for the class of 

workers covered by this report. 

In its previous evaluation of petition SEC-00028, NIOSH concluded that for the period from January 

1948 through December 1957, it has access to sufficient information to either: (1) estimate the 

maximum external radiation dose for every type of cancer for which radiation doses are reconstructed 

that could have been incurred under plausible circumstances by any member of the class; or (2) 
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estimate the external radiation doses to members of the class more precisely than a maximum dose 

estimate. This current evaluation has found no evidence to the contrary. 

Adequate reconstruction of medical dose is likely to be feasible by using bounding assumptions in the 

technical information bulletin, Dose Reconstruction from Occupationally Related Diagnostic X-Ray 

Procedures (ORAUT-OTIB-0006), and Y-12 Plant technical basis documents, collectively referred to 

as ORAUT-TKBS-0014. 

6.3 Class Parameters Associated with Infeasibility 

HHS has designated an SEC class associated with SEC-00028 for Y-12 Plant workers for the period 

from January 1948 through December 1957 (HHS, 2006). The time period covered by this current 

report is unchanged from that previously designated by HHS in 2006. NIOSH therefore recommends 

that the class include the time period from January 1, 1948 through December 31, 1957. 

7.0 Summary of Feasibility Findings for Petition SEC-00186 

This report evaluates the feasibility for completing dose reconstructions for employees at the Y-12 

Plant from January 1, 1948 through December 31, 1957. NIOSH determined that members of this 

class may have received radiation exposures from uranium, thorium, their associated decay progeny, 

and various radionuclides arising as a result of cyclotron operations. NIOSH lacks sufficient 

information, which includes thorium and cyclotron-related bioassay data, source term data, and 

workplace monitoring data that would allow it to estimate the potential thorium and cyclotron-related 

exposures to which the proposed class may have been exposed. 

A recent review of existing SEC class definitions evaluated criteria such as consistency, applicability 

and whether any class definitions needed to be corrected by NIOSH (NIOSH 2010). In this review 

NIOSH determined that the class definition as defined in SEC-00028 needed revising, because 

problems existed with the implementation of the previous class. In addition, through the course of 

ongoing dose reconstruction and research, NIOSH has determined that, due to undocumented worker 

movements across the site, limited claimant-specific information pertaining to work locations, and a 

determination by the Department of Labor (DOL) that employment records do not indicate work 

locations, NIOSH is unable to eliminate any specific worker from potential exposure scenarios based 

on assigned work location. NIOSH has found that a determination cannot always be made as to the 

specific area an employee worked in, or whether an employee should have been monitored for 

radiological exposures. Accordingly, NIOSH has determined that it is necessary to remove the areaspecific and monitoring criteria from the class description associated with SEC-00028 thorium and 

cyclotron exposures for the period from January 1, 1948 through December 31, 1957. As such, 

NIOSH has determined that it is also necessary to expand the SEC class definition to include all areas 

of the Y-12 Plant, and all employees of DOE, its predecessor agencies, and their contractors and 

subcontractors who worked at the Y-12 Plant during the period from January 1, 1948 through 

December 31, 1957. The SEC-00186 evaluation recommends a class that is consistent with current 

DCAS methods for defining a recommended SEC class. 
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NIOSH has documented herein that it cannot complete the dose reconstructions related to this petition. 

The basis of this finding demonstrates that NIOSH does not have access to sufficient information to 

estimate either the maximum radiation dose incurred by any member of the class or to estimate such 

radiation doses more precisely than a maximum dose estimate. 

Consistent with its findings associated with SEC-00028 (NIOSH, 2006a; NIOSH, 2006b), NIOSH 

finds that it is not feasible to estimate, with sufficient accuracy, the internal radiation doses received 

by members of the proposed class of employees from January 1, 1948 through December 31, 1957. 

Although NIOSH found that it is not possible to completely reconstruct radiation doses for the 

proposed class, NIOSH intends to use any internal and external monitoring data that may become 

available for an individual claim (and that can be interpreted using existing NIOSH dose 

reconstruction processes or procedures). Therefore, dose reconstructions for individuals employed at 

Y-12 during the period from January 1948 through December 1947, but who do not qualify for 

inclusion in the SEC, may be performed using these data as appropriate. 

8.0 Evaluation of Health Endangerment for Petition SEC-00186 

The health endangerment determination for the class of employees covered by this evaluation report is 

governed by EEOICPA and 42 C.F.R. § 83.14(b) and § 83.13(c)(3). Pursuant to these requirements, if 

it is not feasible to estimate with sufficient accuracy radiation doses for members of the class, NIOSH 

must determine that there is a reasonable likelihood that such radiation doses may have endangered 

the health of members of the class. The regulations require NIOSH to assume that any duration of 

unprotected exposure may have endangered the health of members of a class when it has been 

established that the class may have been exposed to radiation during a discrete incident likely to have 

involved levels of exposure similarly high to those occurring during nuclear criticality incidents. If 

the occurrence of such an exceptionally high-level exposure has not been established, then NIOSH is 

required to specify that health was endangered for those workers who were employed for a number of 

work days aggregating at least 250 work days within the parameters established for the class or in 

combination with work days within the parameters established for one or more other classes of 

employees in the SEC. 

NIOSH has determined that members of the class were not exposed to radiation during a discrete 

incident likely to have involved levels of exposure similarly high to those occurring during nuclear 

criticality incidents. However, the evidence reviewed in this evaluation indicates that some workers in 

the class may have accumulated chronic radiation exposures through intakes of radionuclides and 

from direct exposure to radioactive materials. Consequently, NIOSH is specifying that health was 

endangered for those workers covered by this evaluation who were employed for a number of work 

days aggregating at least 250 work days within the parameters established for this class or in 

combination with work days within the parameters established for one or more other classes of 

employees in the SEC. 
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9.0 NIOSH-Proposed Class for Petition SEC-00186 

The evaluation defines a single class of employees for which NIOSH cannot estimate radiation doses 

with sufficient accuracy. This class includes all employees of the Department of Energy, its 

predecessor agencies, and their contractors and subcontractors who worked at the Y-12 facility in Oak 

Ridge, Tennessee from January 1, 1948 through December 31, 1957, 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. 

10.0 Evaluation of Second Similar Class 

In accordance with § 83.14(a), NIOSH may establish a second class of coworkers at the facility, 

similar to the class defined in Section 9.0, for whom NIOSH believes that dose reconstruction may not 

be feasible, and for whom additional research and analyses are required. If a second class is 

identified, it would require additional research and analyses. Such a class would be addressed in a 

separate SEC evaluation rather than delay consideration of the current claim. At this time, NIOSH has 

not identified a second similar class of employees at the Y-12 Plant for whom dose reconstruction 

may not be feasible. 
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11.0 References 

42 C.F.R. pt. 81, Guidelines for Determining the Probability of Causation Under the Energy 

Employees Occupational Illness Compensation Program Act of 2000; Final Rule, Federal 

Register/Vol. 67, No. 85/Thursday, p 22,296; May 2, 2002; SRDB Ref ID: 19391 

42 C.F.R. pt. 82, Methods for Radiation Dose Reconstruction Under the Energy Employees 

Occupational Illness Compensation Program Act of 2000; Final Rule; May 2, 2002; SRDB Ref ID: 

19392 

42 C.F.R. pt. 83, Procedures for Designating Classes of Employees as Members of the Special 

Exposure Cohort Under the Energy Employees Occupational Illness Compensation Program Act of 

2000; Final Rule; May 28, 2004; SRDB Ref ID: 22001 

42 U.S.C. §§ 7384-7385 [EEOICPA], Energy Employees Occupational Illness Compensation 

Program Act of 2000; as amended; DCAS website 

Air Monitoring, 1943-1959, Weekly Air Sample Reports, various types of air monitoring reports for Y12 on various dates from 1943 to 1959; SRDB Ref ID: 642 

Assessment, 2001, Atypical Radionuclide Assessment at the Y-12 National Security Complex, Y-12 

Radiological Control Organization; Environment, Safety and Health; Y-12 National Security 

Complex; May 17, 2001; SRDB Ref ID: 12492 

DOE, 2000, Guide of Good Practices for Occupational Radiological Protection in Uranium 

Facilities, Washington, D.C.; 2000; SRDB Ref ID: 4617 

Electronuclear, 1954, Electronuclear Research Division Semiannual Progress Report for Period 

Ending September 20, 1954, R. S. Livingston; ORNL-1795; Oak Ridge National Laboratory; 

November 4, 1954; SRDB Ref ID: 16637 

Health Physics Program, 1957, The Y-12 Health Physics Program, Union Carbide Nuclear Company, 

Y-12 Health Physics Department; December 1957; SRDB Ref ID: 14022 

HHS, 2005, Final Effect of Designation of a Class of Employees for Addition to the Special Exposure 

Cohort, Department of Health and Human Services, Federal Register / Vol. 70, No. 190 / Monday, 

October 3, 2005 / Notices; Page 57,602; Notice for SEC-00018; SRDB Ref ID: 71519 

HHS, 2006, Final Effect of Designation of a Class of Employees for Addition to the Special Exposure 

Cohort, Department of Health and Human Services, Federal Register / Vol. 71, No. 184 / Friday, 

September 22, 2006 / Notices; Page 55,477; Notice for SEC-00028; SRDB Ref ID: 71521 

HHS, 2008, Final Effect of Designation of a Class of Employees for Addition to the Special Exposure 

Cohort, Department of Health and Human Services, Federal Register / Vol. 73, No. 196 / Wednesday, 

October 8, 2008 / Notices; Page 58,966; Notice for SEC-00098; SRDB Ref ID: 71523 
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Livingston, 1958, Electronuclear Research Division, Annual Progress Report for Period Ending 

October 1, 1957, Livingston, R.S.; Oak Ridge National Laboratory: Oak Ridge, Tennessee; April 15, 

1958; SRDB Ref ID: 11945 

McLendon, 1960, Personnel Radiation Exposure Data Correspondence with G. W. Flack, McLendon, 

J. D.; August 25, 1960; SRDB Ref ID: 3694 

Murray, January 1948, Health Physics Progress Report, Murray, R.; Y-12 Plant: Oak Ridge, 

Tennessee; January 1-31, 1948; SRDB Ref ID: 8602 

Murray, February 1948, Health Physics Progress Report, Murray, R.; Y-12 Plant: Oak Ridge, 

Tennessee; February 1-29, 1948; SRDB Ref ID: 8602 

NIOSH, 2005, SEC Petition Evaluation Report for Petition SEC-00018, Y-12 Plant; National Institute 

for Occupational Safety and Health (NIOSH); June 13, 2005; OSA Ref ID: 100898 

NIOSH, 2006a, SEC Petition Evaluation Report for Petition SEC-00028, Y-12 Plant; National 

Institute for Occupational Safety and Health (NIOSH); April 7, 2006; OSA Ref ID: 101192 

NIOSH, 2006b, Supplement to SEC Petition Evaluation Report for Petition SEC-00028, Y-12 Plant; 

National Institute for Occupational Safety and Health (NIOSH); June 8, 2006; OSA Ref ID: 101193 

NIOSH, 2008, SEC Petition Evaluation Report for Petition SEC-00098, Y-12 Plant; National Institute 

for Occupational Safety and Health (NIOSH); May 14, 2008; OSA Ref ID: 106134 

NIOSH, 2010, DCAS Assessment Report, Review of SEC Class Definitions, National Institute for 

Occupational Safety and Health (NIOSH), November 3, 2010; SRDB Ref ID: 99551 

NIOSH-IREP, 2002, NIOSH Interactive RadioEpidemiological Program (NIOSH-IREP) Technical 

Documentation, National Institute for Occupational Safety and Health, Office of Compensation 

Analysis and Support; June 18, 2002; SRDB Ref ID: 22398 

Oak Ridge, 1993, Oak Ridge Studies, Phase I Report, Volume II, Part A, Dose Reconstruction 

Feasibility Study, prepared by ChemRisk (Division of Mclaren/Hart) for the Tennessee Department of 

Health and the Oak Ridge Health Agreement Steering Panel; September 1993; SRDB Ref ID: 13188 

Oak Ridge, 1999, Uranium Releases from the Oak Ridge Reservation – a Review of the Quality of 

Historical Effluent Monitoring Data and a Screening Evaluation of Potential Off-Site Exposures; 

Reports of the Oak Ridge Dose Reconstruction, Vol. 5, The Report of Project Task 6; prepared by 

ChemRisk (Division of Mclaren/Hart) for the Tennessee Department of Health; July 1999; SRDB Ref 

ID: 12715 

ORAUT-OTIB-0006, Dose Reconstruction from Occupationally Related Diagnostic X-Ray 

Procedures, Rev. 03 PC-1; Oak Ridge Associated Universities; December 21, 2005; SRDB Ref ID: 

20220 
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ORAUT-OTIB-0047, Rev. 00, External Radiation Monitoring at the Y-12 Facility During the 1948-

1949 Period; September 20, 2005; SRDB Ref ID: 19462 

ORAUT-TKBS-0014-2, Technical Basis Document for the Y-12 National Security Complex: Site 

Description; Rev. 02; Oak Ridge Associated Universities; November 8, 2007; SRDB Ref ID: 36045 

ORAUT-TKBS-0014-5, Technical Basis Document for the Y-12 National Security Complex: 

Occupational Internal Dose, Rev. 02 PC1; Oak Ridge Associated Universities; October 10, 2006; 

SRDB Ref ID: 30047 

ORAUT-TKBS-0014-6, Technical Basis Document for the Y-12 National Security Complex: 

Occupational External Dosimetry; Rev. 02; Oak Ridge Associated Universities; December 18, 2009; 

SRDB Ref ID: 77701 

ORNL, 1994, Oak Ridge National Laboratory: The First Fifty Years; L. Johnson and D. Schaffer; 

University of Tennessee Press; 1994; SRDB Ref ID: 11916 

ORNL-1173, Progress Report - Part I, Electromagnetic Research Division; July 1, 1951 to September 

31, 1951; SRDB Ref ID: 11943 

ORNL-1196, The Oak Ridge 86-Inch Cyclotron, Oak Ridge National Laboratory; SRDB Ref ID: 

11942 

ORNL-1392, Production of Polonium 208, Oak Ridge National Laboratory; August 1952; SRDB Ref 

ID: 11936 

Owings, 1995, Historical Review of Accountable Nuclear Materials at the Y12 Plant (extracted 

pages), compiled by E. Owings; U.S. Department of Energy – Oak Ridge Office; July 28, 1995; 

SRDB Ref ID: 691 

Polonium-208, 1952, Production of Polonium 208, August 1952, Final Report on Termination of 

Project, R. S. Livingston and J. A. Martin; August 1952; SRDB Ref ID: 11936 

Progress Report, 1958, Electronuclear Division Annual Progress Report for Period Ending October 1, 

1957, R. S. Livingston; ORNL-2434; April 15, 1958; SRDB Ref ID: 11945 

Progress Report, 1962, Electronuclear Division Annual Progress Report for Period Ending December 

31, 1961, R. S. Livingston and A. Zucker; ORNL-3257; August 17, 1962; SRDB Ref ID: 11949 

Progress Report, 1963, Isotopes Development Center Progress Report; Reactor- and CyclotronProduced Isotopes; July-October 1962; compiled by T. A. Butler; April 1, 1963; SRDB Ref ID: 

11934 

Rad Handbook, 1998, Handbook of Health Physics and Radiological Health, 3rd Edition, B. Shleien, 

L. A. Slaback, Jr., B. K. Birky, editors; 1998; SRDB Ref ID: 22737 (commonly available from public 

resources) 
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Recycled Uranium, 2000, Recycled Uranium Mass Balance Project Y-12 National Security Complex 

Site Report, Y-12 National Security Complex; December 2000; SRDB Ref ID: 16500 

Rees, 1967, Health Physics: Principles of Radiation Protection, Rees, D. J.; The M.I.T. Press: 

Cambridge, Massachusetts; 1967; SRDB Ref ID: Publicly available 

Safety Analysis, 1967, A Safety Analysis of the Oak Ridge Critical Experiments Facility, prepared by 

the Facility Staff; ORNL/TM-349, Rev. 1; Oak Ridge National Laboratory; February 1967; SRDB 

Ref ID: 15655 

Safety Review, 1962, A Safety Review of the Oak Ridge Critical Experiments Facility, prepared by the 

Facility Staff; ORNL/TM-349; Oak Ridge National Laboratory; December 1962; SRDB Ref ID: 

15646 

Technical Basis, 2001, Technical Basis for the External Dosimetry Program at the Y-12 National 

Security Complex, prepared by L. S. Oxley; Radiological Control Organization, Y-12 National 

Security Complex; August 2, 2001; SRDB Ref ID: 8467 

Technical Basis, 2003, Technical Basis for the Internal Dosimetry Program, prepared by L. M. 

Snapp; Radiological Control Organization, Y-12 National Security Complex; March 5, 2003; SRDB 

Ref ID: 12324 

Semiannual Report, 1956, Applied Health Physics Semi-Annual report, July 1956 – December 1956, 

Oak Ridge National Laboratory, Health Physics Division; No issue date, but presumably early 1957; 

SRDB Ref ID: 13248 

Struxness, May 1948, Health Physics Industrial Hygiene Progress Report, Struxness, E. G.; Y-12 

Plant: Oak Ridge, Tennessee; May 1-31, 1948; SRDB Ref ID: 8602 

Struxness, December 1948, Health Physics Industrial Hygiene Progress Report, Struxness, E. G.; Y12 Plant: Oak Ridge, Tennessee; December 1-31, 1948; SRDB Ref ID: 8602 

Struxness, 1949, Health Physics Hygiene Progress Report, Struxness, E. G.; Y-12 Plant: Oak Ridge, 

Tennessee; February 1-28, 1949; SRDB Ref ID: 8602 

Struxness, November-December 1950, Health Physics Progress Report, Struxness, E.G.; Y-12 Plant: 

Oak Ridge, Tennessee; November 1, 1950 to December 31, 1950; SRDB Ref ID: 8602 

Struxness, January-June 1951, Health Physics Progress Report, Struxness, E. G.; Y-12 Plant: Oak 

Ridge, Tennessee; January 1, 1951 to June 30, 1951; SRDB Ref ID: 8602 

Struxness, July-December 1951, Health Physics Progress Report, Struxness, E. G.; Y-12 Plant: Oak 

Ridge, Tennessee; July 1, 1951 to December 31, 1951; SRDB Ref ID: 8602 

Struxness, January-July 1952, Health Physics Progress Report, Struxness, E. G.; Y-12 Plant: Oak 

Ridge, Tennessee; January 1, 1952 to July 1, 1952; SRDB Ref ID: 8602 
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Struxness, January-June 1953, Health Physics Progress Report, Struxness, E. G.; Y-12 Plant: Oak 

Ridge, Tennessee; January 1, 1953 to June 30, 1953; SRDB Ref ID: 8602 

West, 1980, Names of Persons Having Dosimetry Information for the 1947-1950 Period in the Y-12 

Record Center, C. M. West; Union Carbide, Nuclear Division; October 16, 1980; SRDB Ref ID: 

24018 - PRIVACY ACT INFORMATION 

West, 1993, Brief History of the Y-12 External Monitoring Program, Memorandum, West, C. M.; Oak 

Ridge Institute for Science and Education: Oak Ridge, Tennessee; June 7, 1993; SRDB Ref ID: 8532

Wilcox, 1999, An Overview of the History of Y-12: A Chronology of Some Noteworthy Events and 

Contributions During Y-12’s First Fifty Years by a Group of Participants in the History, W. J. 

Wilcox, Jr., April 1999; SRDB Ref ID: 8358 

Wilcox, 2001, An Overview of the History of Y-12, 1942 - 1992, W. J. Wilcox, Jr., American Museum 

of Science and Energy; August 2001; SRDB Ref ID: 9609 

Y-12 Plant, 1963, Y-12 Plant Quarterly Health Physics Report – Fourth Quarter CY 1962, Y-12 

Plant; Oak Ridge, Tennessee; March 5, 1963; SRDB Ref ID: 23618 
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Attachment 1: Data Capture Synopsis 

Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Primary Site/Company Name: Y-12 Plant 

1942-present, DOE Other Site Names: NA 

Physical Size of the Site: 811 acres holding over 350 

buildings. Personnel Data: In 1945, more than 22,000 workers at the 

site. During the Cold War 8,000 people worked around the clock. Noted 6,866 employees in June 1963 and 6,000 in 2011. 

Bioassay data, 86-inch cyclotron program and radiation protection, buildings and years where thorium was present, external exposure information, foundry health physics, handling and working with Np, in-vivo monitoring program and results, list of names and badge numbers, neutron field measurement, uranium air limits and their impact on Y-12, personnel notebooks, plant procedures, plutonium air problem, progress reports, radiation generating devices, radiation safety manual, radiological incidents, radiological surveys (airborne, contamination, etc.), record book of materials, run sheets from 86-inch 

cyclotron, separation of isotopes, neutron film results, sunflower foundry employees, thorium program lung count results, transuranic hazard assessment, uranium in effluent, urinalysis and fecal sample 

program related information, various technical basis documents, applying thorium surface contamination limits, internal dosimetry program, background subtraction and critical level for ET1 dosimeters, calibration factors, estimating the shallow dose equivalent using HBG element four readings, and dosimetry quality control program information. 

07

State Contacted: See description State was not contacted due to Y-12 being an active Department of 

Energy site. 

NA 

Claimant Provided Work products from inter-agency working groups - links between 

exposure to occupational hazards and illnesses in the DOE contractor workforce and a hearing before the workers' compensation board state of New York. 

04

College Park NARA Meteorological conditions, machining of uranium metal, and monthly 

status and progress reports. 

08

Colorado State University Library A cost/benefit study of a formal safety program. 04Curtiss-Wright Shipping information and orders. 04Department of Labor/Paragon Background report and evaluation of resurvey requirements for the 

former atomic energy commission portion of the Lake Ontario Ordinance Works, request for scrap evaluation, shipment of Schenectady wastes to Oak Ridge, and a visit from Cotter Corporation personnel. 

12

Page 41 of 73 
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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

DOE Argonne National Laboratory (ANL-E) Organization of National Nucleonics Program and plutonium scrap 

processing information. 

04

DOE Brookhaven National Laboratory Ambient air monitoring parameters at DOE facilities. 03DOE Germantown Beryllium history, monthly accountability, thorium information, site 

history, and Manhattan District history. 

03

DOE Hanford Annual and monthly progress reports, environmental monitoring and 

protection committee information, smelting uranium-contaminated ferrous metal scrap, production of tritium, and accountability survey data. 

07

DOE Lawrence Berkeley National Laboratory (LBNL) Laboratory contacts. 02DOE Legacy Management - Grand Junction Office Accomplishments of the National Lead Company of Ohio, Electro 

Metallurgical weekly production report, requests for material transfers, storage/disposal requests, electromagnetic separation of isotopes at Oak Ridge, results of mobile gamma scanning activities, results of soil sample analysis, return of thorium from Savannah River programs, return of thorium from Davison Chemical, LOOW production report describing materials shipped to Y-12, an accidental radiation excursion 

at Y-12, and history of Hanford. 

03

DOE Legacy Management - Morgantown Health and mortality studies of federal nuclear workers, uranium in 

urine samples, appraisal of occupational medical program, bioassay department highlights report, comparison of FMPC's uranium in urine sample results with Y-12's results, comprehensive epidemiologic data resource, DOE studies finding excess cancer mortality at several DOE 

nuclear facilities, disposal of thorium residues, Extrusion Plant (RMI) receipts and shipments, progress and production reports and orders, material balance report by facility, plutonium content of NLO feed materials, production order enriched uranium to Y-12, results of uranium urines, thorium shipments, trip reports, and uranium urine exchange program information. 

02

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

DOE Legacy Management - MoundView (Fernald Holdings, includes Fernald Legal Database) 

Air emissions annual report, annual report of the Health and Safety Division, Colonie site receipts of depleted uranium, DOE health and mortality study, environmental reports, Grand Junction processing of feed material scraps, incineration of radioactive solid wastes, major thorium campaigns and accountability documents, radioactive waste 

shipments, radiological incidents, shipping and receipt documents for 

enriched uranium and thorium, thorium bioassay investigations, thorium derby metal for Y-12, thorium nitrate specifications, trip reports, and Y-12 Plant thorium powder or pellet procurement specifications. 

01

DOE Los Alamos National Laboratory (LANL) Excursion at the Oak Ridge criticality experiments facility, nonnuclear 

consolidation environmental assessment, polonium contamination at Pajarito, low-level mixed waste streams for the DOE complex, radiation excursions at the ORNL critical experiments laboratory, and radioactive waste disposal and related issues. 

12

DOE Oak Ridge Gaseous Diffusion Plant (K-25) Procedure manual for production plants, compilation of data relating to 

personnel historical radiation exposures in the Y-12 Plant, and a uranium salvage procedure. 

06

DOE Oak Ridge National Laboratory (X-10) Radiological incidents, history of the Analytical Chemistry Division of 

Oak Ridge National Laboratory, Aircraft Nuclear Propulsion Project progress report, cyclotron operations, electromagnetic isotope separations, evaluation of neutron dosimetry, exposures received from typical diagnostic x-ray examinations at ORNL, health physics instrument manual, neutron dosimetry with the ORNL badge, Oak Ridge 86-inch cyclotron, X-ray facility reviews, production of 

radioisotopes in the ORNL 86-inch cyclotron, quarterly progress report, radiation safety manual, stable isotope separation in calutrons, technical basis for nuclear accident dosimetry, inventory of electromagnetically enriched isotopes, X-10 medical X-ray compliance survey, and Y-12 film monitoring program. 

03

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

DOE Oak Ridge Operations Records Holdings Task Group Vault 

Building index, contamination control, discontinuation of Dupont film, employee work history records, external exposure reports, film badge program, foundry beta radiation control, health physics records, internal exposures at Y-12 , personnel participating in decontamination work, monthly health physics report, collection and recovery of airborne tuballoy, radiological incidents, radiological surveys, reduction of radiation exposures, technical basis for beta skin dose calculations at the Y-12 plant, uranium dust concentrations, urinalysis and whole body count information, African Metals invoices, materials in 0101 area - Clinton Engineer Works, and the storage of U-235 from Los Alamos at Clinton Engineer Works. 

12

DOE Office of Scientific and Technical Information (OSTI) 

Closed-cycle beta process, alpha II calutron development, uranium recovery by spray cleaning, and thorium receipts. 

01

DOE Paducah Gaseous Diffusion Plant Alpha hazards from neptunium, computer program for whole body 

count, disposal of stored "tru" waste, environmental assessments and reports, estimates of transuranium alpha fed to Paducah cascade, exposure assessments, health protection information on uranium metal, in vivo monitoring results, inventory of radioactivity released to environments, land burial of radioactive waste at the Paducah Plant, licensing of byproduct material, neptunium and plutonium plant material balance, dust studies, radiation protection program, radioactive contaminants in Paducah scrap, radioactive effluent release, monitoring and control, radioactive waste management, radiological incidents, study of plutonium and fission products, Paducah information, technical basis for the Centralized External 

Dosimetry System, trip reports, waste disposal criteria, and Y-12 TLD results that include Paducah area dosimeters. 

10

DOE Portsmouth Gaseous Diffusion Plant Eighth Analytical Services Forum Paducah Gaseous Diffusion Plant. 09DOE Rocky Flats Plant MED/AEC/DOE External Dosimetry Technology. 10DOE Sandia National Laboratories/NM Technical basis for workplace air monitoring of airborne radioactive 

material at Y-12 and Ross Aviation shipment surveys and documents. 

10

DOE Savannah River Site Dosimetry visitors cards. 08DOE Weldon Spring Analysis of long term data on uranium in air. 11Dr. Denise DeGarmo Personal Files Biological research program at Clinton National Laboratories. 11

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Environmental Measurements Laboratory (EML) Library Air sampling for the control of internal exposure from enriched 

uranium at Y-12 and in vivo counting as a device for evaluating uranium exposure. 

01

Federal Records Center - Atlanta Uranium tolerances, finger film, and tritium information. 04Federal Records Center - Dayton Radiation dose determinations from indium foils in multi-plant 

security badges, limits for material from K-25 and Y-12 potentially contaminated with tritium, and dose estimates for a Y-12 incident. 

03

Federal Records Center - Denver Mortality among radiation workers at a plutonium weapons facility. 06Federal Records Center - San Bruno Beta run reports, personnel medical records handling, personnel 

assignment logs, schedule for track B, and fuels and materials development programs. 

11

General Atomics Criticality incident at Oak Ridge. 08Hagley Museum & Library General history of Clinton Engineer Works, Race for the Bomb, the 

Hanford Story, and uranium experimental program on heat treatment. 

09

Interlibrary Loan Environmental levels of radioactivity at Atomic Energy Commission 

Installations and work history reports for oxide conversion facility. 

04

Internet - DOE Comprehensive Epidemiologic Data Resource (CEDR) 

Health physics hygiene progress report and the impact of downsizing and reorganization on employee health and well-being at the DOE Y12 Plant. 

01

Internet - DOE Hanford Declassified Document Retrieval System (DDRS) 

Fourth Atomic Energy Commission Air Cleaning Conference. 11

Internet - DOE Legacy Management Considered Sites Monthly progress report and a preliminary site survey report for the 

former Elza Gate Warehouse area, Oak Ridge. 

12

Internet - DOE OpenNet Criticality accident at the Y-12 Plant, declassification of the quantity 

of enriched lithium produced at Y-12, Manhattan District history, monthly status and progress reports, semiannual reports of the Atomic Energy Commission, operational accidents and radiation exposure experience, release of radioactivity to the environs request by AEC, and uranium dust exposure and lung cancer risk in four uranium processing operations. 

10

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Internet - DOE OSTI Energy Citations Clean atmosphere approach to radiological decontamination of 

concrete surfaces, model for uranium lung clearance at the Y-12 plant, Y-12 discharge of enriched uranium to the sanitary sewer, study of TLD beta calibration factor for exposure to depleted uranium, coaxial germanium detectors in the Y-12 in vivo monitor, disposal of United Nuclear Company materials at the Y-12, environmental survey report, modeling of Elza Gate contaminated material, and a Pinellas Plant feasibility study. 

10

Internet - DOE OSTI Information Bridge DOE Complex buried waste characterization assessment, Conversion 

and Blending Facility highly enriched uranium to low enriched uranium as uranium hexafluoride, disposition of highly enriched uranium obtained from the Republic of Kazakhstan environmental assessment, electromagnetically enriched isotopes inventory, environmental evaluation and reports, export license issued for DOE Oak Ridge for shipment of uranium-235, human radiation experiments, in vitro data and comments, list of ERDA radioisotope customers, occupational dose reduction, post construction report for the United Nuclear Corporation disposal site, radiological risk assessment of a radioactively contaminated site, remedial investigation 

of Bear Creek Valley at the Oak Ridge Y-12 Plant, sampling approach for characterization of the Scarboro community, testing of the Y-12 Plant criticality accident alarm system detectors at the Sandia Pulsed Reactor Facility, metal fabrication program for the Clinton Engineering Works and the Hanford Engineering Works including the dummy slug program, waste vitrification projects, Y-12 salvage yard scrap metal characterization study, and Y-12 Plant solid waste management system. 

11

Internet - Environmental Management Linking Legacies - Wastes. 10

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Internet - Google Accountability and control of sealed radioactive sources, annual site 

environmental reports, Clinton Engineer Works photos, Clinton Laboratory expands to Y-12 buildings, depleted uranium operations at Y-12, division progress reports, Eastman at Oak Ridge during World War II, environment monitoring assessment and reports, epidemiological studies, evaluation of iodine-131 releases, historical evaluation of the film badge dosimetry program at Y-12, liquid waste disposal at Oak Ridge National Laboratory, major relocation of highly enriched uranium completed at Y-12, Manhattan Engineer District history, neutron and gamma dosimeter intercomparison study, Oak Ridge, Tennessee, warehouses site fact sheet, operating Oak Ridge's "calutrons", radiological incidents, Site X, Oak Ridge, Tennessee (map), status of highly enriched uranium processing capability at Y-12 building 9212, study of metal hydrides, Oak Ridge 86-inch cyclotron, urine bioassay program, personal air sampling (PAS) data in the internal dosimetry program, and Y-12 history and fact sheet. 

01

Internet - National Nuclear Security Administration (NNSA) - Nevada Site Office 

Babcock & Wilcox Technical Services cited for violation. 01

Internet - NRC Agencywide Document Access and Management (ADAMS) 

DOE inventory report, evaluation of the potential for recycling of scrap metals from nuclear facilities, feasibility study for the United Nuclear Corporation disposal site at the Oak Ridge Y-12, integrated data base: U.S. spent fuel and radioactive waste inventories, projections, and characteristics, and a soil management plan for the Oak Ridge Y-12. 

10

Iron Mountain Storage Facility Survey of Control Over Source and Special Nuclear Materials 

National Distillers and Chemicals Corporation. 

09

Kansas City Plant Statement of Dr. Victor H. Reis, before the subcommittee on Military 

Procurement Committee on National Security, US House of Representatives. 

10

Mesa State College, CO Recovery of uranium from carnotite ores and progress report of 

carnotite studies. 

11

Metals & Controls Corp Analysis of Possible Nuclear Material Losses and Possible Liabilities 

Associated with Present Fuel Manufacturing. 

08

Mound Museum Disposition of depleted salvage material, exposure to polonium from a 

neutron source, and fabrication of weapon components. 

07

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

NARA - Atlanta AEC handbook on Oak Ridge operations, annual health protection 

review, bioassay results and procedures, calutron beam study, control of radiation hazards by Carbide and Carbon Chemicals Division, environmental data, equipment numbering system, film badge program description, hazards of piles at Y-12, monthly accountability reports, organization charts, personnel exposure data, progress reports, radiological and criticality incidents, radiological surveys, report of annual health protection review - New Brunswick Lab, reports of destruction of classified material, shipments from Metal Hydrides to AEC facilities, shipping receipts, work done at Iowa State college, and handling fissionable material. 

12

NARA - Kansas City Historical Information from Property Insurance Association on 

Niagara Falls Storage Site / African Metals Leased Areas. 

06

National Technical Information Service (NTIS) Feasibility study of the correlation of lifetime health and mortality 

experience of AEC and AEC contractor employees. 

08

New York State Department of Environmental Conservation 

Recovery of Uranium from Sylvania Scrap, contract no. AT(40-1). 07

NIOSH Audit report confirmatory bioassay testing at selected sites, highly 

enriched uranium safety and health vulnerabilities associated with storage of highly enriched uranium, Los Alamos Scientific Laboratory information, nondestructive testing of uranium, radioactive waste shipment, recycled uranium mass balance project, history of the Oak Ridge National Laboratory's first 25 years, strikes at Y-12, trip reports, and worker outreach meeting minutes. 

10

NIOSH/SC&A BWXT-ORAU correspondence 2003-2005, recycled uranium project 

report, highly enriched uranium working group report, NP237-U238 alloy radiation safety requirements, remarks on personnel monitoring at Y-12, technical basis document for the Internal Dosimetry Program at the Y-12, uranium urinalysis program, and Y-12 complex description. 

02

Oak Ridge Library for Dose Reconstruction Status report on Clinch River study, high-flux isotope reactor 

description, and engineering development of hydraulic fracturing as a method for permanent disposal of radioactive wastes. 

03

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Oak Ridge Associated Universities (ORAU) Brief history of the Y-12 external monitoring program, correction 

factors for film badge data, data collection, validation, and description for mortality studies, dosimetry records and radiation hazards 

questionnaire, film badge data, names of persons having dosimetry information, radiation dosimetry for epidemiologic lung cancer study, history of buildings at Y-12, and information on the calutron program for uranium enrichment. 

12

ORAU Team Accounting for incomplete personal monitoring data on penetrating 

gamma doses, exposure matrix for the Mallinckrodt Chemical Company, effect of threshold energy and angular response of NTA film on missed neutron dose at Y-12, annual report radiation exposures for DOE and contractor employees, radiological incidents, external radiation monitoring at Y-12, health and mortality among contractor employees at DOE facilities, evaluation of the film badge dosimetry program at Y-12, historical evaluation of the film badge dosimetry program at Y-12, potential missed dose to nuclear weapons assemblers, specific tables of isotopic production, Tiger Team assessment of the Pantex Plant, Y-12 exposure database, and analysis of electronic personnel exposure data from Y-12. 

05

Sanford Cohen & Associates (SC&A) Assessment for acceptance of enriched uranium at Y-12, radiation 

worker health at Y-12, Oak Ridge reservation annual site environmental report, photographic film as a pocket radiation dosimeter, and recycled uranium mass balance project information. 

12

SC&A - Atlanta NARA Glove decontamination and thorium metal processes. 09SC&A - Idaho National Engineering Laboratory Environmental report and airborne radionuclide waste management 

information. 

06

Science Applications International Corporation (SAIC) Annual summary of whole body radiation exposures to external 

penetrating radiation. 

09

Southern Illinois University Nuclear fuel fabrication, Oak Ridge site description, observations on 

uranium exposures, and visit requests. 

10

University of Rochester Return of Uranium Peroxide to Oak Ridge. 08University of Tennessee Library Creation of Clinton Engineer Works and a health physics report. 11

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Table A1-1: Data Capture Synopsis for the Y-12 Plant 

Data Capture Information Data Captured Description D

Unknown Annual radiation dose reports, annual environmental reports, 

designation of race tracks by number - Y12 and extension, dosimeter 

response characterization, estimation of radiation doses to the lungs of 

early uranium workers, excretion of uranium from mixed exposures under industrial conditions, fifth semiannual report of the atomic energy commission, flow of materials through the nuclear weapons complex, glossary of Y-12 coded terminology, health physics survey instruments used at Clinton, in vivo method to determine uranium lung burden, Mallinckrodt Plant inspections, miscellaneous Fernald documents, monthly status and progress reports, neutron dose equivalent and energy spectra measurements at ORNL and Y-12, overview of the history of Y-12, protective equipment evaluation, radiation safety manual, radiological incidents, radiological surveys, relationship between in vivo and urinalysis data collected, Rocky Flats site history, Simonds Saw & Steel material balance report, Westinghouse Nuclear Fuels Division and Westinghouse Atomic Power Development information, and X-ray radiation measurements in calutron cubicles. 

02

Westinghouse Site (MO) Accidental radiation excursion at Y-12, estimated lung exposure, in 

vivo count results, and procedures and assignments for restricted personnel. 

04

TOTAL 

Table A1-2: Internet Database Searches for the Y-12 Plant 

Database/Source Keywords / Phrases 

NOTE: The normally-prescribed set of publicly-accessible Internet database searches was not performed for this evalua

sufficient information already had been obtained through searches conducted for the previous three Y-12 evalua

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Table A1-3: OSTI Documents Requested for the Y-12 Plant 

Document Number Document Title 

TID-5210 REF ID: 40189 

Vacuum Problems and Techniques dated 1/1/1950 10

Y-681 REF ID: 40302 

Electromagnetically Enriched Isotopes: Inventory, October 31, 1950 dated 10/31/1950 

10

Y-727 REF ID: 40305 

Electromagnetically Enriched Isotopes: Inventory, February 28, 1951 dated 2/28/1951 

10

Y-772 REF ID: 40299 

Electromagnetically Enriched Isotopes: Inventory, May 31, 1951 dated 5/31/1951 

10

Y-783 REF ID: 40303 

Electromagnetically Enriched Isotopes dated 6/30/1951 10

Y-790 REF ID: 40304 

Electromagnetically Enriched Isotopes: Inventory, July 31, 1951 dated 7/1/1951 

10

Y-819 REF ID: 40298 

Electromagnetically Enriched Isotopes: Inventory, September 30, 1951 dated 9/30/1951 

10

ORNL-1284 REF ID: 44484 

Electromagnetically Enriched Isotopes: Inventory, April 30, 1952 dated 4/30/1952 

10

ORNL-1355 REF ID: 44486 

Electromagnetically Enriched Isotopes: Inventory, July 31, 1952 dated 7/31/1952 

10

ORNL-1489 REF ID: 44490 

Electromagnetically Enriched Isotopes: Inventory, January 31, 1953 dated 3/17/1953 

10

ORNL-1568 REF ID: 44492 

Electromagnetically Enriched Isotopes: Inventory, May 31, 1953 dated 1/1/1953 

10

ORNL-1640 REF ID: 44502 

The Inventory of Electromagnetically Enriched Isotopes dated 10/31/1953 

10

ORNL-1691 REF ID: 44506 

The Inventory of Electromagnetically Enriched Isotopes dated 3/5/1954 

10

ORNL-1428 REF ID: 44487 

Electromagnetically Enriched Isotopes: Inventory, October 31, 1952 dated 10/31/1952 

10

AECD-4084 REF ID: 49009 

Gaseous Flow dated 8/27/1946 10

CF-60-1-17 REF ID: 49012 

Supplementary Report No. 1 on Vacuum Systems dated 1/6/1960 10

Y/DQ-40 REF ID: 59682 

Technical Basis for the Internal Dosimetry Program at the Y-12 Plant 

dated March 2, 1992 

01

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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. 

Attachment 2: Stable and Radioactive Isotopes Produced and/or Separated and 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 

1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Aluminum-26m Aluminum-28 Antimony-121 305 mg 112 mg Antimony-122 961 mCi 4,735 mCi Antimony-123 20 mg Antimony-124 21 mCi 207 mCi Antimony-125 52,100 mCi 4 mCi Antimony-Be 278 mCi Argon-37 5 mCi 6 mCi 36 mCi Argon-38 11 mCi 9 mCi 6 cc Arsenic-74 Arsenic-76 73 mCi Arsenic-77 28 mCi 32 mCi Barium-130 20 mg 81 mg Barium-131 19 mCi 3 mCi Barium-132 10 mg 55 mg 

A blue or dark-shaded data value cell indicates stable isotopes. 

Page 53 of 73 
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Barium-133 5 mCi 23 mCi Barium-134 540 mg Barium-135 20 mg 50 mg Barium-136 50 mg Barium-137 50 mg Barium-138 50 mg 300 mg Barium-140 9 mCi 13 mCi 688 mCi Beryllium-7 933 mCi Bismuth-209 Bismuth-210 7 mCi 982 mCi 92 mCi Boron-10 10,260,721 mg 12,589,425 mg Boron-11 132,194 mg 313,338 mg Boron-13 Bromine-79 1 mg 20 mg Bromine-82 16 mCi 2 mCi 1,889 mCi Cadmium-106 10 mg Cadmium-108 59 mg Cadmium-109 

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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at Y-12

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Cadmium-111 367 mg Cadmium-112 40 mg 136 mg Cadmium-113 40 mg 41 mg Cadmium-114 100 mg 330 mg Cadmium-115 147 mCi 233 mCi 9 mCi Cadmium-115m 21 mCi 20 mCi 33 mCi Cadmium-116 25 mg 100 mg Calcium-40 225 mg 1,200 mg Calcium-42 235 mg Calcium-43 3 mg 63 mg Calcium-44 b 65 mg 21 mg Calcium-45 8 mCi 38 mCi 2,852 mCi Calcium-46 40 mg 3 mg Calcium-48 259 mg 20 mg Carbon-12 10 mg 10 mg Carbon-13 1 mg Carbon-14 1,983 mCi 

55 of 73
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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Cerium-136 20 mg Cerium-138 Cerium-140 25 mg 230 mg Cerium-141 5,782 mCi 9,313 mCi 88 mCi Cerium-142 20 mg 507 mg Cerium-144 235 mCi 99 mCi 1686 mCi Cesium-132 Cesium-134 1,001 mCi 2,344 mCi 1,562 mCi Cesium-136 Cesium-137 1,789 mCi Cesium-138 5 mg Chlorine-35 2,650 mg 2,017 mg Chlorine-36 2,366 mCi 10 mCi Chlorine-37 75 mg 100 mg Chromium-49 b Chromium-50 4303 mg 527 mg Chromium-51 4 mCi 8,475 mCi 7,384 mCi Chromium-52 28,062 mg 110 mg 

56 of 73
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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Chromium-53 120 mg 40 mg Chromium-54 2,929 mg 10 mg Cobalt-55 Cobalt-56 Cobalt-57 7,635 mCi 4,031 mCi 4 mCi Cobalt-58 23 mCi 4 mCi 158 mCi Cobalt-60 55 mCi Cobalt-61 Copper-63 1,360 mg 30,110 mg Copper-64 2 mCi 16,642 mCi Copper-65 185 mg 30,476 mg Deuterium-Zr 3,834 mCi 2 mCi Dysprosium-156 2 mg Dysprosium-157 Dysprosium-160 20 mg 167 mg Dysprosium-161 2,002 mg 682 mg Dysprosium-162 2,000 mg 687 mg Dysprosium-163 1,786 mg 762 mg 

57 of 73
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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Dysprosium-164 2,264 mg Erbium-150 Europium b Europium-145 Europium-149 Europium-151 3,540 mg 3,790 mg Europium-152/154 7 cc 6.5 cc 33 mCi Europium-153 3,415 mg 3,787 mg Europium-155 76 mCi 0 mCi Fissions Products 22 mCi 11 mCi 999 mCi Fluorine-18 Gadolinium-149 Gadolinium-152 78 mg 59 mg Gadolinium-153 Gadolinium-154 35 mg 510 mg Gadolinium-155 896 mg 1,050 mg Gadolinium-156 48 mg 1,000 mg Gadolinium-157 1,373 mg 1,051 mg Gadolinium-158 128 mg 1,155 mg 

58 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Gadolinium-160 264 mg 1,440 mg Gallium-64 Gallium-67 75 Ci Gallium-69 140 mg 1,203mg Gallium-71 280 mg Gallium-72 890 mCi 14 mCi Germanium-68 Germanium-70 10,251 mg 360 mg Germanium-72 15,487 mg Germanium-73 3,224 mg Germanium-74 34,586 mg 1,830 mg Germanium-76 5,049 mg Gold-195 Gold-198 10 mCi 175,654 mCi Gold-199 305 mCi 36,091 mCi 60 mCi Hafnium-174 17 mg 29 mg Hafnium-176 15 mg 60 mg Hafnium-177 858 mg 

59 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Hafnium-178 20 mg 35 mg Hafnium-179 889 mg 76 mg Hafnium-180 150 mg 102 mg Hafnium-181 29 mCi 268 mCi Helium-3 97 mCi Holmium b Hydrogen-3 5,195 cc Indium-113 742 mg Indium-114 101 mCi Iodine-124 Iodine-125 65 mCi Iodine-127 Iodine-129 13.5 mCi 90 mCi Iodine-130 4 mg Iodine-131 50.8 mCi 10.4 mg Iridium-190 Iridium-191 12 mg 5 mg Iridium-193 10 mg 250 mg 

60 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Iron-52 b Iron-54 2,873 mg 525 mg Iron-55 60 mCi 33 mCi 111 mCi Iron-55/59 79 mCi Iron-56 3,859 mg 3,026 mg Iron-57 25 mg 2,953 mg Iron-58 329 mg 675 mg Iron-59 589 mCi 146 mCi 820 mCi Lanthanum-139 Lanthanum-140 131 mCi Lead-204 5 mg 135 mg Lead-206 406 mg 50 mg Lead-207 330 mg 905 mg Lead-208 1,350 mg 236 mg Lead-209 1.45 Ci Lithium-6 6,300 mg 1,292,922 mg 4,768,458 mg Lithium-7 58,118 mg 4,585,329 mg Lutetium-174 

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SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Magnesium-24 746 mg 250 mg Magnesium-25 50 mg 1,103 mg 381 mg Magnesium-26 495 mg Magnesium-27 Manganese-51 b Manganese-52 b Manganese-52m b Manganese-54 411 mCi Manganese-57 Mercury-197 6 mCi 20 mCi Mercury-198 35 mg Mercury-199 2 mg 10 mg Mercury-200 45 mg Mercury-201 7 mg 15 mg Mercury-202 58 mg 94 mg Mercury-203 22 mCi 878 mCi Mercury-204 27 mg 40 mg Molybdenum-92 20 mg 260 mg 

62 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Molybdenum-94 14 mg 40 mg Molybdenum-95 30 mg 2,920 mg Molybdenum-96 20 mg 5 mg Molybdenum-97 10 mg 10 mg Molybdenum-98 35 mg 50 mg Molybdenum-100 210 mg Neodymium-142 5,300 mg Neodymium-143 3,859 mg 3,260 mg Neodymium-144 200 mg 5,200 mg Neodymium-145 1,354 mg 2,810 mg Neodymium-146 290 mg 5,075 mg Neodymium-147 248 mCi 8 mCi Neodymium-148 40 mg 53 mg Neodymium-150 60 mg 117 mg Nickel-58 4,550 mg 1,255 g Nickel-60 8,117 mg 190 mg Nickel-61 72 mg 20 mg 

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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Nickel-62 2,575 mg 100 mg Nickel-63 3 mCi 7 mCi 90 mCi Nickel-64 210 mg 60 mg Niobium-92 Niobium-93 Niobium-94 Niobium-95 76 mCi 77 mCi 56 mCi Nitrogen-13 Nitrogen-15 13,843 mg Osmium-190 Osmium-191 47 mCi 55 mCi 43 mCi Palladium-102 10 mg Palladium-103 Palladium-104 30 mg Palladium-105 30 mg Palladium-106 30 mg Palladium-108 15 mg 10 mg Palladium-109 2 mCi 190 mCi Palladium-110 20 mg 75 mg 

64 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Phosphorus-32 120 mCi Platinum-185 Platinum-190 11 mg Platinum-192 3 mg 12 mg Platinum-194 6,016 mg 40 mg Platinum-195 25 mg Platinum-196 60 mg 155 mg Platinum-198 10 mg 5 mg Plutonium (feed) 110 g Plutonium-240 1,110 mCi 4.4 g Plutonium-241 0.9 g Plutonium-242 0.107 g Polonium-207 Polonium-208 2.6 g Polonium-209 Polonium-211 Potassium-38m b Potassium-39 4,120 mg 1,787 mg 

65 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Potassium-40 2 mg 19 mg Potassium-41 30 mg 1,720 mg 201 mg b Potassium-42 8,333 mCi Potassium-44 0.5 g Praseodymium-142 302 mCi 2,757 mCi Praseodymium-143 12 mCi 10 mCi Promethium-147 1 mCi 8 mCi Promethium-148 Radium-219 Rhenium-185 55 mg 1,220 mg Rhenium-186 61 mCi Rhenium-187 40 mg 75 mg Rubidium-74 Rubidium-85 5,708 mg 200 mg Rubidium-86 1,978 mCi Rubidium-87 3,864 mg 265 mg Ruthenium-96 36 mg 

66 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Ruthenium-98 3 mg 12 mg Ruthenium-99 75 mg 9 mg 126 mg Ruthenium-100 9 mg 81 mg Ruthenium-101 150 mg 9 mg 116 mg Ruthenium-102 5 mg 215 mg 30 mg Ruthenium-103 628 mCi 2,190 mCi 44 mCi Ruthenium-104 75 mg 54 mg 41 mg Ruthenium-106 209 mCi 74 mCi 420 mCi Samarium-144 150 mg 585 mg Samarium-145 Samarium-147 285 mg 1,180 mg Samarium-148 1,180 mg Samarium-149 1,495 mg 1,060 mg Samarium-150 285 mg 1,000 mg Samarium-152 550 mg 1,150 mg Samarium-153 717 mCi 330 mCi 136 mCi Samarium-154 294 mg 2,407 mg Scandium-40 

67 of 73
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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Scandium-43 b Scandium-44 b Scandium-44m b Scandium-46 114 mCi 80,350 mCi Selenium-74 110 mg 14 mg Selenium-75 167 mCi 333 mCi Selenium-76 56 mg Selenium-77 60 mg 110 mg Selenium-78 100 mg Selenium-80 55 mg 200 mg Selenium-82 80 mg 310 mg Silicon-28 5,310 mg 40 mg Silicon-29 30 mg 559 mg Silicon-30 50 mg 30 mg Silver-107 830 mg 100 mg Silver-109 1,050 mg 2,200 mg Silver-110 420 mCi 421 mCi 273 mCi Silver-111 672 mCi 368 mCi 100 mCi 

68 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Sodium-22 Sodium-24 59 mCi 31 mCi 2,602 mCi Strontium-84 12 mg 151 mg Strontium-85 1,676 mCi Strontium-86 2,826 mg 765 mg Strontium-87 1,790 mg 1,000 mg Strontium-88 4,016 mg 210 mg Strontium-89 12 mCi 1,474 mCi 1,439 mCi Sulfur-32 220 mg 50 mg Sulfur-33 45 mg 8 mg Sulfur-34 6 mg 135 mg Sulfur-35 1,924 mCi 1,250 mCi Technicium-99 75 mCi 161 mCi 82 mCi Tellurium-120 1 mg Tellurium-122 4 mg 100 mg Tellurium-123 100 mg Tellurium-123m 115 mg Tellurium-124 300 mg 

69 of 73
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Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Tellurium-125 3,200 mg 430 mg Tellurium-126 50 mg 430 mg Tellurium-128 115 mg Tellurium-130 1,050 mg 300 mg Thallium-203 1,007 mg Thallium-204 1 mCi 0.37 mCi 0 mCi Thallium-205 1,014 mg Thorium-223 Thorium-230 150 g 259 mCi Thorium-nat 0.1966 g Thulium-168 b Tin-112 3 mg Tin-113 1,712 mCi 251 mCi 3,000 g Tin-114 5 mg Tin-115 508 mg 5 mg Tin-116 1,714 mg 165 mg Tin-117 1,080 mg 165 mg 

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SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Tin-118 1,790 mg 120 mg Tin-119 170 mg Tin-120 837 mg 234 mg Tin-122 150 mg 20 mg Tin-124 150 mg 25 mg Titanium-44 Titanium-45 b Titanium-46 4,763 mg 90 mg Titanium-47 5,576 mg 25 mg Titanium-48 53,655 mg 1,050 mg Titanium-49 4,178 mg 2,912 mg Titanium-50 4,086 mg 20 mg Tungsten-180 18 mg 13 mg Tungsten-181 Tungsten-182 8,500 mg 499 mg Tungsten-183 3,546 mg 2,079 mg Tungsten-184 186 mg 530 mg Tungsten-185 118 mCi 26 mCi 29 mCi 

71 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Tungsten-186 7,185 mg 650 mg Tungsten-187 0 mCi 95 mCi 79 mCi Turbium b Uranium (feed) 4.265 Ci Uranium-227 Uranium-234 18 g 

per run 

100 g 

per run 13,600 g 4.945 Ci 5 mCi 

Uranium-235 10 mg 2.308 g Uranium-236 10.7 mg 50 mg 129.5143 g Uranium-238 1.8 g 352 mg 0.4798 g Vanadium-47 b Vanadium-48 b Vanadium-50 100 mg 2 mg Vanadium-51 100 mg Yttrium-87 Yttrium-88 Yttrium-90 126 mCi 35 mCi 2,288.294 g Yttrium-91 0 mCi 40 mCi 279 mCi Zinc-63 2 g Zinc-64 351 mg 328 mg 

72 of 73
SEC-00186 07-18-11 

Source: NIOSH, 2006a; NIOSH, 2006b A yellow or light-shaded data value cell with no entry indicates the presence of the radioisotope. A yellow or light-shaded data value cell with a “b” indicates that the isotope was used in Atomic Cross Sectional Studies. A blue or dark-shaded data value cell indicates stable isotopes. 

73 of 73

Table A2-1: Stable and Radioactive Isotopes Produced and/or Separated and Purified at 

Isotope 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 

Zinc-65 250 mCi 940 mCi 1,068 mCi Zinc-66 4,993 mg 31 mg Zinc-67 135 mg Zinc-68 2,917 mg 151 mg Zinc-70 103 mg 25 mg Zinc-72 Zirconium-89 Zirconium-90 10,046 mg 4,783 mg Zirconium-91 3,040 mg 150 mg Zirconium-92 4,722 mg Zirconium-94 4,313 mg Zirconium-95 1,455 mCi Zirconium-96 122 mg 22 mg